MXPA00002036A - Biphasic lipid vesicle composition for transdermal administration of an immunogen - Google Patents

Abstract

A composition for transdermal administration of an immunogen is described. The immunogen is entrapped in lipid vesicles having an oil-in-water emulsion in the central core compartment. The vesicles are administered transdermally to elicit an immune response in a subject.

Description

COMPOSITION OF BIFASIC IPIDIC VESICLE FOR TRANSDERMAL ADMINISTRATION OF AN IMMUNOGEN FIELD OF THE INVENTION The present invention relates to the administration of an immunogen for the purpose of immunization or vaccination. The immunogen is trapped in liquid vesicles having an oil-in-water emulsion in the central nuclear compartment. The vesicles are administered transdermally for administration of the trapped immunogen.

REFERENCES Benson, M.L. et al., Can. J. Comp. Med. 42_: 368-369 (1978). Berggren, K.A. et al., Am. J. Vet. Res. 42 ^: 1383-1388 (1981). Chanock, R.M., Lerner, R.A., Brown, F. and Ginsberg, H. "New Approaches to Immunization, Vaccines" 86, Cold Spring Harbor, N.Y. (1987). Collier, J.R., et al., Am. J. Vet. Med. Assoc. 140: 807-810 (1962). Czerkinsky, C., et al., J. Immunol. Methods 110: 29-36 (1988). Harland, R.J., et al., Can. Vet. J. 33: 734-741 (1992). Santus, G.C. and R.W. Baker, J. Controlled Reeléase, 25: 1-20 (1993).

P1109 / 00MX BACKGROUND OF THE INVENTION An immune response can be induced against an almost unlimited variety of substances. There are two categories of humoral and cellular immune response. In a humoral response, the antigen or foreign substance is recognized by specific receptors on the surfaces of the lymphocytes and certain B lymphocytes are stimulated to multiply. These cells produce large numbers of antibodies that have the ability to bind antigens. After binding, the binding to the antigen is eliminated or destroyed. In a cellular or cell-mediated immune response, T lymphocytes, in particular helper and killer T lymphocytes, are active to recognize and destroy the foreign substance. The process to induce immunity as a preventive measure against infectious diseases is known as immunization. Immunization can be passive, when antibodies are administered to an animal to provide short-term or active immunity. Active immunization is more commonly known as vaccination, wherein an exterminated or weakened antigen or fragment thereof is introduced into an animal. The antigens sensitize the immune system so that if that antigen enters the body later, the antibodies P1109 / 00MX rapidly produce to eliminate and / or destroy the invading antigen. Most vaccines are preparations that contain the organism or part of the organism, against which protection is sought. The organism is exterminated or weakened enough not to cause disease but to induce immunity. Some vaccines contain chemically modified bacterial toxins. Vaccines against a variety of infectious diseases are available, for example, live attenuated vaccines are administered to protect against measles, mumps, rubella, yellow fever and polio. Diphtheria and tetanus vaccines contain inactivated bacterial toxins. Cholera, typhoid fever, pertussis, rabies, viral hepatitis B and influenza contain dead organisms or in the case of hepatitis B, only a part of the virus. Vaccines are usually administered by injection into the upper arm or in the case of polio vaccine, administered orally. Administration by injection is not always convenient, particularly in third-world countries, for soldiers in the field or for non-human subjects, including horses, cows and dogs.

P1109 / 0OMX SUMMARY OF THE INVENTION Accordingly, it is an object of the invention to provide an easy and effective way of administering a vaccine. It is another object of the invention to provide a biphasic lipid vesicle composition for transdermal administration of an antigen trapped in the lipid vesicles. In one aspect, the invention includes a composition for eliciting an immune response to an immunogen in a subject. The composition includes a suspension of biphasic lipid vesicles having a central nuclear compartment containing an oil-in-water emulsion and entrapped in the biphasic lipid vesicles., an immunogen. In one embodiment, the immunogen is an antigen derived from bacterial, viral, parasitic, plant or fungal origin. The immunogen is effective to elicit a humoral immune response, or alternatively is effective to elicit a cell-mediated immune response. In another embodiment, the composition further includes an adjuvant entrapped in the lipid vesicles. In another embodiment, the suspension of lipid vesicles also includes a cutaneous permeation enhancer.

P1109 / 00MX Preferred permeation enhancers include acylated fatty acids and unsaturated fatty acids. In another aspect, the invention includes a method for eliciting an immune response to an immunogen in a subject. The method includes transdermally administering to the subject, a dose of immunogen. As described above, the immunogen is entrapped in biphasic lipid vesicles having a central core compartment containing an oil-in-water emulsion. In yet another aspect, the invention includes a method for transdermally administering an immunogen to a subject by applying a device to the skin of the subject. The device includes (i) a suspension of lipid vesicles formed by mixing an oil-in-water emulsion with vesicle-forming lipids. The vesicles are composed of (a) a lipid bilayer outer membrane composed of said vesicle-forming lipids, (b) a central nuclear compartment containing that oil-in-water emulsion and (c) trapped in the vesicles a dose of an effective immunogen to elicit an immune response; (ii) a reservoir adapted to retain the suspension of lipid vesicles and adapted to release the lipid vesicles therefrom; and (iii) means for fixing the device to a subject for administration P1109 / 00MX transdermal immunogen. In yet another aspect, the invention includes a device for transdermal administration of an immunogen that includes a lipid vesicle suspension formed by mixing an oil-in-water emulsion with vesicle-forming lipids. The vesicles are composed of (i) an outer membrane composed of lipid bilayer composed of said vesicle-forming lipids, (ii) a core nuclear compartment containing the oil-in-water emulsion, and (iii) entrapped in the vesicles, a dose of effective immunogen to elicit an immune response. The device also includes a reservoir adapted to retain the suspension of lipid vesicles and adapted to release the lipid vesicles therefrom and means for securing the device to a subject for transdermal administration of the immunogen. In one embodiment, the reservoir in the device is defined by an impermeable support member and a membrane effective in its use to allow the passage of lipid vesicles from the reservoir. In another embodiment, the suspension of lipid vesicles includes a permeation enhancer. For example, the permeation can be a fatty acylated amino acid or an unsaturated fatty acid. The immunogen trapped in the vesicles of P1109 / 00MX preferably has a molecular weight of approximately between 100-100,000,000 daltons. In one embodiment, the immunogen is one that is used in vaccination of an animal or a human. In one embodiment, the means for securing the device to the subject is an adhesive layer adjacent to the membrane. The vesicle suspension may include an auxiliary, entrapped in the lipid vesicles or included in the suspension. These and other objects and features of the invention will be more fully appreciated from the following description when taken considering the drawings that accompany it.

BRIEF DESCRIPTION OF THE DRAWINGS OR FIGURES Figure 1 illustrates a biphasic lipid vesicle prepared according to the invention; Figure 2 shows a general scheme for preparing lipid vesicles having an oil-in-water emulsion in the central core, which is used in the device of the invention; Figures 3A-3C are cross-sectional views of transdermal devices suitable for use in the present invention; Figure 4 is a graph showing serum antibody responses, expressed as optical density at 405 nm, after the P1109 / 00MX transdermal administration of leukotoxin trapped in biphasic lipid vesicles from a device according to the invention; Figure 5 is a graph showing the proliferative response of mass spleen cells isolated from control mice (full squares) and from mice immunized with leukotoxin, administered from transdermal patches containing 50 μg (full triangles ) or 100 μg (inverted triangles) of leukotoxin trapped in biphasic lipid vesicles; Figure 6 is a graph showing the secretion of interleukin-4 by spleen cells by mass as determined by drop assay with enzyme-linked immunosorbent (ELISPOT), for control mice and for mice immunized with leukotoxin, administered to from transdermal patches with a content of 50 μg or 100 μg of leukotoxin trapped in lipid vesicles; Figure 7 is a bar graph showing the serum IgG response in mice immunized with chicken egg lysozyme transdermally administered with various formulations of non-biphasic lipid vesicles. I-V; Figures 8A-8D are bar graphs showing the secretion of interleukin-4 and β-interferon from spleen cells (Figures 8A-8B) and P1109 / 00MX from cells drained from lymph nodes (Figures 8C-8D) after immunization with 50 μg of chicken egg lysozyme from various lipid biphasic vesicle formulations nos. I-V, as determined by ELISPOT assay; and Figure 9 is a bar graph showing the IgG that in mouse serum after subcutaneous and transdermal immunization with chicken egg lysozyme trapped in biphasic lipid vesicles.

DETAILED DESCRIPTION OF THE INVENTION I. Definitions In the sense in which they are used herein, the terms below shall have the following meanings. "Antigen" refers to a substance or material that is specifically recognized by an antibody and / or is combined with an antibody. "Auxiliary" refers to a substance or material that enhances an immune response when administered together with an antigen. An auxiliary can also be used to elicit an immune response more quickly. "Biphasic lipid vesicles" refers to lipid particles formed from a vesicle-forming lipid and having an oil-in-water emulsion in the central nuclear compartment. The P1109 O OMX terms lipid vesicle, vesicle, and biphasic lipid vesicle are used interchangeably in the present. "Immunogen" refers to a substance or material, including an antigen, that has the ability to induce an immune response. Immunogens can elicit immune responses either alone or in combination with an adjuvant. An immunogen can be synthetic or natural and can be, for example, an organic or inorganic compound such as a hapten, a protein, peptide, polysaccharide, nucleoprotein, nucleic acid or lipoprotein. The immunogens may be derived from a bacterial, viral or protozoan, plant or fungal organism or fractions thereof. "Dosage" refers to the amount of immunogen necessary to elicit an immune response. The amount varies with the animal, the immunogen and the presence of auxiliaries as described below. The immunization dose is easily determined by methods known to those skilled in the technical field, for example, through immunization of host animals and stimulation studies (Chanock, et al., (1987)). "Deposit" refers to a storage structure that can hold and distribute a medium there.

P1109 / 00MX II. Suspension of Biphasic Lipid Vesicle A. Biphasic Lipid Vesicles As discussed above, the invention includes a composition of lipid vesicles for the transdermal administration of an immunogen. A lipid vesicle according to the invention is illustrated schematically in Figure 1. Now, with reference to this figure, the biphasic lipid vesicles of the present invention are multilamellar lipid vesicles, such as vesicle 10 shown in the figure, composed of a series of lipid bilayers, two of which are partially shown as bilayers 12, 14. Each lipid bilayer is composed of two layers of vesicle-forming lipid, set forth below, wherein each lipid molecule, like molecule 16, is oriented with its main polar group 16a exposed to a hydrophilic compartment 18 and its hydrophobic tail 16b aligned with neighboring lipid molecules. The innermost bilayer in the vesicle defines a central nuclear compartment 20. According to an important feature of the invention, the compartment in the core of the lipid vesicle contains an oil-in-water emulsion, represented in the figure by small drops 22, 24, 26. As will be discussed later, the oil-in-water emulsion is trapped in the lipid vesicles when preparing a P1109 / 00MX oil emulsion in water stabilized with surfactant, represented in the figure as the small hydrophilic drop 22a surrounded by a layer of tensoactive molecules 22b. The emulsion is mixed with vesicle-forming lipids to form lipid bilayers around the emulsion. The immunogen can be trapped in the lipid vesicles in a variety of places, depending on the physicochemical properties of the immunogen. For example, a hydrophilic immunogen may be the aqueous phase of the oil in water emulsion in the central nuclear compartment or in the aqueous phase in the compartment 18 between the lipid bilayers. A more hydrophobic immunogen may be contained in the oil phase of the oil in water emulsion or in the lipid bilayer, as indicated by 30 in the figure. Methods for preparing the biphasic lipid vesicles to trap the immunogen are described below.

B. Immunogen Trapped in Biphasic Lipid Vesicle As discussed above, the composition of the present invention includes a suspension of biphasic lipid vesicles containing an entrapped immunogen effective to elicit an immune response, for example, for immunization or vaccination purposes.

P1109 / 00MX In general, a wide variety of immunogens are suitable for use in the present invention. The following list of antigens is provided as a means of illustration and does not mean that it is exclusive: influenza virus antigens (such as haemagglutinin and neuraminidase antigens), tel la pertussis antigens (such as pertussis toxin, filamentous haemagglutinin, pertactin), antigens human papilloma virus (HPV), Hel i cobacter pylori antigens, rabies antigens, tick-borne encephalitis (TBE) antigens, meningococcal antigens (such as serogroup A, B, C, Y and W-135 capsular polysaccharides), tetanus antigens (such as tetanus toxoid), diphtheria antigens (such as diphtheria toxoid), pneumococcal antigens (such as the capsular polysaccharide Streptococcus pneumoniae type 3), tuberculosis antigens, human immunodeficiency virus (HIV) antigens (such as GP-120, GP-160), cholera antigens (such as cholera toxin B subunit), staphylococcal antigen (such as staphylococcal enterotoxin B), antigens higella (as shigella polysaccharides), vesicular stomatitis virus antigen (such as vesicular stomatitis virus glycoprotein), cytomegalovirus (CMV) antigens, hepatitis virus antigens (such as hepatitis A (HAV), B (HBV), C (HCV), D (HDV) and G (HGV), respiratory virus antigens P1109 / 00MX syncytial (RSV), herpes simplex antigens or combinations thereof (e.g., diphtheria, pertussis and tetanus (DPT) combinations). Suitable antigens also include those that are supplied for induction of tolerance, such as retinal antigens. Antigens are also considered for immunization / vaccination against anthrax and Yersinia pes tis. Preferred antigens include Bordetel pertussis antigens, meningococcal antigens, tetanus antigens, diphtheria antigens, pneumococcal antigens, tuberculosis antigens and RSV antigens. In another preferred embodiment, the entrapped immunogen has a molecular weight of about 100 to 100,000,000 daltons, more preferably between 100 and 500,000 daltons and preferably superlatively between 100 and 100,000 daltons. In studies carried out to support the present invention, leuco toxin, an exotoxin produced by Pas teurell a haemolyti ca and hen egg lysozyme were trapped in biphasic lipid vesicles and delivered transdermally, in the manner described below.

III. Preparation of Biphasic Lipid Vesicles As discussed above, the biphasic lipid vesicles of the present invention include P1109 / 00MX in the central nuclear compartment of the lipid vesicle and in the aqueous space separating the lipid bilayers, an oil-in-water emulsion. In general, said lipid vesicles are prepared by mixing an oil-in-water emulsion with vesicle-forming lipids. Importantly, the oil-in-water emulsion is stabilized with a surfactant before being mixed with the vesicle-forming lipids. That is, the small drops of oil in the emulsion are surrounded by a surfactant, preferably surrounded by a monolayer of surfactant. In a preferred embodiment, the stabilizing surfactant is distinct from the vesicle-forming lipid component that forms the biphasic lipid vesicle bilayers. More specifically, the biphasic lipid vesicles according to the present invention are prepared according to the general procedure outlined in Figure 2. The selected lipid components are solubilized in a suitable solvent, which in a preferred embodiment is a pharmaceutically acceptable hydrophilic solvent. , as a polyol, for example, propylene glycol, ethylene glycol, glycerol or an alcohol such as ethanol or mixtures of these solvents. Depending on the physico-chemical properties of the lipid components and the selected solvent, it may be necessary to heat the mixture, for example, between 40 and P1109 / 00MX 80 ° C. The lipid components necessarily include a vesicle-forming lipid, by which is meant an antipathetic lipid having a hydrophobic tail and a head group which in water can spontaneously form as bilayer vesicles. Vesicle-forming lipids are preferably those having two hydrocarbon chains, usually acyl chains and in which the head group is polar or non-polar. There are a variety of synthetic vesicle forming lipids and vesicle-forming lipids existing in nature suitable for use, such as phospholipids, including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinosyl tol, fasfatidic acid and sphingomyelin, in which the two hydrocarbon chains they usually have a length of approximately 14 to 22 carbon atoms and have varying degrees of unsaturation. These lipids can be obtained commercially or prepared according to published methods. In addition to the vesicle-forming lipid component, the lipid vesicles of the present invention may include other lipid components that have the ability to stably incorporate into the lipid bilayers, with their hydrophobic portions in contact with the inner region Hydrophobic P1109 / 00MX of the bilayer membrane and its polar head groups oriented towards the outer, polar surface of the membrane. For example, glycolipids, ceramides and sterols, such as cholesterol, coprostanol, cholestanol and cholestane, long chain fatty acids (C? 6 to C22), such as stearic acid, can be incorporated into the lipid bilayer. Other lipid components that could be used include fatty amines, fatty acylated proteins, acylated fatty peptides, oils, fatty alcohols, glyceride esters, petrolatum and waxes. It will also be appreciated that a cutaneous permeation enhancer may be included in the lipid components of the lipid vesicle, as discussed below. Continuing with the reference to Figure 2, the oil-in-water emulsion is prepared by dissolving a surfactant in water or in oil, depending on the hydrophilic-lipophilic balance (HBL) of the surfactant. In a preferred embodiment, the surfactant is mixed with distilled water and added to an oil phase for the formation of an emulsion. The emulsion can be formed using agitation as homogenization or emulsification or can be formed by microemulsion techniques that do not involve agitation. The resulting emulsion preferably has water as the continuous phase and oil as the dispersed phase. According to an important feature of the invention, the oil-in-water emulsion is stable P1109 / 00MX because the small oil droplets in the dispersed phase are surrounded by the surfactant. That is, the hydrophilic portion of each molecule of surfactant is extended to the aqueous phase of the emulsion and the hydrophobic portion is in contact with the small hydrophilic drop. As will be discussed below, lipid vesicles are formed by mixing the oil-in-water emulsion with vesicle-forming lipids. If the emulsion is not stabilized with surfactant before coming into contact with the vesicle-forming lipids, the vesicle-forming lipids could first act to stabilize the emulsion rather than to form the lipid bilayers around the oil-in-water emulsion. The surfactants which are suitable for the formation of the oil-in-water emulsion are numerous, including both cationic, anionic and non-ionic surfactants or amphoteric surfactants. In one embodiment, the preferred surfactant is a cationic surfactant, such as linoleamidopropyl propylene glycol dimonium chloride phosphate, cocamido chloride (alkylamido derived from coconut oil) propylene glycol dimonium and stearamide propylene glycol dimonium chloride phosphate. These are synthetic phospholipid complexes that are commercially available from Mona Industries, Inc. (Patterson, NJ) under the names Commercial P1109 / 00MX Phospholipid EFAMR, Phospholipid SVMR and Phospholipid SVCMR, respectively. Another preferred vesicle-forming lipid that is used as the primary lipid component of the biphasic lipid vesicle bilayers is hydrogenated phosphatidylcholine. Exemplary anionic surfactants include acylglutamates, such as cocoyl (alkyloyl derivative of coconut oil) triethanolamine glutamate, sodium lauroyl glutamate, alkyloyl (hydrogenated tallow derivative), sodium glutamate and sodium cocoyl glutamate. Non-ionic surfactants including emulsifiers include natural derived emulsifiers, such as polyethylene glycol-60 almond glycerides, avocado oil diethanolamide, ethoxylated jojoba oil (polyethylene glycol-40 acid jojoba and polyethylene glycol-40 jojoba alcohol); polyoxyethylene derivatives, such as polyoxyethylene-20 sorbitan monooleate and polyoxyethylene-20 sorbitan monostearate; lanolin derivatives, such as polyol 20 (LANETH 20) and polyol 40 (LANETH 40); neutral phosphoric esters, such as polypropylene glycol cetyl ether phosphate and diethanolamine oleth-3 phosphate The small oil droplets in the dispersed oil phase preferably have sizes less than about 1 μm, more preferably less than P1109 / 00MX approximately 0.5 μm in diameter. Of course, the microdrop size is easily adjusted by the mixing conditions, for example, cutting and mixing time, etc. It will be appreciated that other components may be added to the oil-in-water emulsion, ie, the oil-in-water emulsion does not need to be just oil, surfactant and water. For example, the emulsion may include antimicrobial agents, such as methylparaben, propylparaben, and reinforcing ingredients such as waxes, fatty alcohols, fatty acid esters, glyceryl stearate, petrolatum, oils and plant extracts and combinations thereof. Specific preferred examples include beeswax, olive oil, glyceryl stearate, cetyl alcohol, stearyl alcohol, myristyl misistrate and cetyl palmitate, stearyl heptanoate and stearyl palmitate. Suitable exemplary formulations for use in the present invention are described below and are disclosed in the joint application of the United States series no. 08 / 507,923, which is considered part of this, as a reference. Continuing with the reference to Figure 2, the stabilized oil-in-water emulsion is mixed with the solubilized vesicle-forming lipid and if added, with other lipid components, eg, cholesterol. The emulsion and P1109 / 00MX lipid components are mixed under conditions that are effective to form multilamellar vesicles having the oil-in-water emulsion in the central compartment. The size of the vesicles is usually between about 0.1 and 100 μm. For use in the present invention, a lipid vesicle size of about 0.5 to 25 μm is preferred, which can be more easily obtained by adjusting the mixing conditions. The composition of lipid vesicles formed according to the invention have a cream-like consistency without further addition of thickening or gelling agents and therefore, are easily applied directly to the skin of a subject for transdermal administration of the entrapped immunogen. Alternatively, the composition of the lipid vesicle can be easily incorporated into the reservoir of a transdermal device. The preparation procedure outlined in Figure 2 results in a population of vesicles with a uniform size distribution and a homogeneous composition, as disclosed and shown in the copending application series no. 08 / 507,293, which expressly and in its entirety, is considered part of this, as a reference. The vesicles are physically stable, that is, little aggregation or fusion of P1109 / OOMX vesicles after storage for a period of one year.

A. Other Components of the Lipid Vesicle The immunogen, depending on its physicochemical properties, can be trapped in the central nuclear compartment of the vesicles, between the lipid bilayers, inside the lipid bilayers in the manner to be described. Water-soluble immunogens are trapped in the central core compartment and in the peripheral compartments between the lipid bilayers by adding the immunogen to the aqueous phase during the preparation of the oil-in-water emulsion. The immunogen, dissolved or suspended in the aqueous phase, is trapped as part of the emulsion during the formation of the lipid vesicle in the addition of the vesicle-forming lipids. The lipophilic immunogens are added to the oil phase during the preparation of the oil-in-water emulsion to trap them in the central compartment and in the peripheral compartments. Additionally or alternatively, lipophilic immunogens can be trapped in the lipid bilayer by adding the immunogen to the vesicle-forming lipid and / or the other lipid components, such as cholesterol.

P1109 / 00MX In one embodiment of the invention, biphasic lipid vesicles include a permeation enhancer to enhance the penetration of trapped antigen. The use of such enhancers has been extensively studied in the technical field of transdermals (Santus et al., 1993) and it will be understood that these enhancers are suitable for use in the present invention. In preferred embodiments, the permeation enhancer is a fatty acylated amino acid, such as monolauroyl lysine or dipalmitoyl lysine, an unsaturated fatty acid such as oleic acid, a short chain fatty acid, such as lauric acid or methyl salicylate. The penetration enhancer may be included in the oil in water emulsion or in the lipid bilayer, in the same manner as described above to include the entrapped immunogen. In some embodiments and as discussed above, the prepared biphasic lipid vesicles that are used in the invention include an antimicrobial agent, such as methylparaben or propylparaben. Said agents can be added to the aqueous phase when the oil in water emulsion is prepared and trapped in the lipid vesicles as part of the aqueous phase. In another embodiment of the invention, an auxiliary is included in the composition of biphasic lipid vesicles. Among the auxiliaries P1109 / 00MX eg emplificativos include Freund's Complete Assistant (CFA), Freund's Incomplete Auxiliary (IFA), aluminum hydroxide, bacterial, viral or synthetic auxiliaries. The auxiliaries act by facilitating and delaying the release of immunogens at the point of administration. Oil-based auxiliaries, for example, induce the formation of granulomas that are populated mainly by macrophages and other antigen-presenting cells. The auxiliaries also help in the delivery of immunogens to the lymphatic system, by placing the immunogens "in close proximity to antigen-presenting cells and immune effectors." While it is known that CFA is a potent auxiliary activator, its use is restricted to use in animals due to the presence of heat-killed mycobacteria or antigenic type epitopes.Alternatively, other auxiliary activators could be used, such as the heat-killed members of the Corynebacterium or Bordatella species, bacterial cell peptidoglycan or muramyl dipeptide, which localize antigens in areas dependent on T cells for antigen presentation and immune cell activation Another class of auxiliary activators that are used in the present invention include agents P1109 / 00MX unfriendly and surfactants, such as saponin, lysolecithin, retinal, Quil A and polymeric pluronic formulations. The effectiveness of surfactant auxiliaries is particularly noticeable when the membrane components are used as immunogens. Other types of auxiliaries include inert vehicles such as bentonite and acrylic vehicles; polyclonal T cell activators as a purified protein derivative (PPD) and polyU: polyA.

IV. Transdermal Device As discussed above, the biphasic lipid vesicle composition of the invention is for use in transdermal administration. The composition can be applied directly to the skin, for example, applied as a lotion, cream or gel or it can be incorporated into a transdermal device. Said device will now be described. The transdermal device of the present invention includes, in its most elementary embodiment, a reservoir adapted to retain during storage and release in the operation lipid vesicles containing a trapped immunogen. Exemplary devices are shown in Figures 3A-3C, however, it will be appreciated that a wide variety of transdermal devices have been described in the technical field and are suitable for use in the present invention.

P1109 / 00MX The exemplary transdermal device 40 shown in Figure 3A includes a reservoir 42 defined by an impermeable support layer 44 and a membrane 46. The support layer and the membrane are gathered around the outer periphery of the device, as indicated at 48. These layers are joined by an adhesive, a thermal seal or the like. The device 40 also includes an adhesive layer 50 as a means for securing the device to the skin of a subject. A release liner 52 is removed before using the device to expose the adhesive layer 50. The backing layer 44 defines the distal side of the patch, i.e., the farthest side of the skin in use. The support layer functions as the primary structural element of the device and provides the device with its mechanical properties, for example, flexibility. The backing layer serves as a protective, impermeable cover that prevents the loss of contents within the reservoir 42. Suitable backing materials include films commercially available for medical use, such as those supplied by 3M Corporation, Dow Chemical or Fasson Medical Industries. Typical support materials are made of polyester or the like and may be pigmented or metallized. The membrane 46 is a fairly porous member that retains the formulation within the reservoir 42, is P1109 / 00MX say, this prevents the mass flow of the formulation out of the reservoir, but allows the passage of the reservoir formulation to the skin. Suitable materials for use as a membrane 16 include non-woven fabrics, such as polyesters, polyethylenes, non-woven polypropylenes and other synthetic polymers. The material is preferably heat sealable or otherwise sealable to the support layer to provide a barrier to the transverse flow of the contents of the deposit. The reservoir 42, defined by the space or gap between the support layer and the membrane, provides a storage structure in which the suspension of lipid vesicles to be administered is retained. The suspension of lipid vesicles will be described in detail below. The adhesive layer 50 is the means by which the device is fixed to the skin. This layer is made of a pharmaceutically acceptable pressure sensitive adhesive, such as polydimethylsiloxane, polyisobutylene, polyacrylate, polyurethane and the like. As shown in Figure 3A, the adhesive layer 50 is an in-line adhesive. It will be understood that the adhesive layer may also be a peripheral adhesive layer or border, as shown in Figure 3B. The device 40 includes a peelable strip or a release liner to cover the P1109 / 00MX surface of the adhesive layer and prevent the loss of the contents of the deposit during storage. Before use, the release liner is removed from the device. The release coating is normally a material impermeable to the contents of the deposit. The release coating is, for example, polyethylene terephthalate and is usually liberable by treatment with a silicone or fluorocarbon. Now with reference to Figure 3B, a second exemplary transdermal device 60 is shown, comprising a support layer 62, a membrane 64 and a peripheral adhesive layer 66. In this embodiment, the support layer 62 and the membrane 64 are heat sealed around the periphery of the device, such as is indicated at 68. A reservoir 70 defined by the space between the support layer and the membrane provides storage for a suspension of lipid vesicles to be administered transdermally. The peripheral adhesive layer 66 is applied directly to the support layer 62. A release coating 72 protects the device during storage. Suitable materials for the support layer, the membrane, the adhesive and the release coating are the same as those described for Figure 3A. A third exemplary transdermal device 80 is shown in Figure 3C. In P1109 / 00MX this device, the contents of the reservoir 82 are in direct contact with the skin when the device is fixed on a subject. The reservoir in this device is composed of an absorbent sponge or a fairly permeable, porous polymer. Suitable materials for the deposit include polyurethane, polyethylene or polypropylene materials. An impermeable support layer 84 prevents loss of contents of the reservoir through the upper, distal side of the device. The support layer is coated on its distal side with an adhesive cover 86, which is protected by a polymeric or backing layer 88. Before use, the peripheral edge of the adhesive cover is exposed by peeling off a release liner 90 and a strip protective layer 92 on the side proximal to the skin of the device. In the aforementioned embodiments, the devices are adhesively attached to the wearer's skin, although other means for attaching the device to the skin, such as an elastic band for arm or an adjustable belt, are considered and are suitable. The membrane in the transdermal device is preferably a fairly permeable, porous membrane, which has minimal resistance to diffusion of the contents of the reservoir relative to the skin. At the same time, the membrane works to prevent the mass flow of the contents of the P1109 / 00MX deposit from the device. As will be discussed below, the reservoir includes lipid vesicles in suspension and the lipid vesicles cross the membrane to contact and penetrate the skin for administration of the entrapped immunogen. Suitable materials that are used as a membrane include hydrophilic and hydrophobic fabrics, polymer and fabric films having a porosity suitable for the transport of lipid vesicles. Said materials may be non-woven materials or fabrics having a defined pore size. A material that is preferred is PecapMR polyester HC7.51 having a pore size of 51 μm (Tetco, Inc., Briarcliff Manor, NY). Other preferred materials are Saatifil PES47126 polyester (Saati Corp., Stamford, CT) and Fluortex 9-COP-105 having a 105 μm mesh size (Tetco, Inc., Briarcliff Manor, NY). It will be appreciated that the membrane can be selected to provide more or less diffusional strength as desired. For example, to design a device where the membrane is of controlled speed, rather than the skin, a membrane with a more closed tissue or a smaller pore size can be selected.

B. Preparation of the Transdermal Device A suspension of biphasic lipid vesicle P1109 / 00MX including the immunogen to be administered transdermally is contained within the reservoir of a transdermal device, such as those illustrated in Figures 3A-3C. The preparation of such devices is known to those skilled in the technical field and the preparation of a specific example of a transdermal device according to the present invention is described in Example 2, set forth below. It will be appreciated that the membrane in the transdermal device is selected depending, in part, on the size of the biphasic lipid vesicles. Normally, the pores of the membrane have a diameter slightly larger than the diameter of the lipid vesicles. In preferred embodiments, the membrane has pores in sizes from 0.1 to 500 μm, more preferably from 0.1 to 200 μm. The difference in size between the pore size of the membrane and the diameter of the lipid vesicle influences the rate of release of the biphasic lipid vesicles of the device. The smaller the difference, the slower the transfer rate of the lipid vesicle. In one embodiment of the invention, biphasic lipid vesicles having a heterogeneous size distribution are contained in the device reservoir. The smaller vesicles include P1109 / 00MX a first immunogen and / or auxiliary and the larger vesicles contain a second immunogen and / or auxiliary. For a given membrane, the smaller vesicles are released from the device at a faster rate than the larger vesicles, resulting in a composition administered first and a composition administered in the second place.

V, Method of Use In another aspect, the invention includes a method for eliciting an immune response to an immunogen in a subject. The method includes transdermally administering to the subject the immunogen entrapped in biphasic lipid vesicles as described herein. In one embodiment, the biphasic lipid vesicles are administered from a transdermal delivery device, such as the one described above with respect to Figures 3A-3C. In studies carried out to support the present invention, biphasic lipid vesicles were prepared to include leukotoxin, an exotoxin produced by Pas teurella haemolyti ca. P. haemolyti ca is a gram-negative bacterium commonly isolated from the lungs of cattle with pneumonic pasteurellosis (Collier et al., 1962). Leukotoxin has been identified as a factor in P1109 / 0OMX potential virulence (Benson et al., 1978; Berggren, et al., (1981)) and the recombinant protein produced in E. col i is used to immunize cattle and protect against fibrinous pneumonia (Harland, et al., 1992). For purposes of the present invention, leukotoxin was used as a model antigen to demonstrate the transdermal delivery of a vaccine antigen to elicit an immune response, for example, an antibody response, in mice. As described in Example 1, the biphasic lipid vesicles were prepared according to the procedure described above to include leukotoxin. A vesicle-forming lipid, hydrogenated phosphatidylcholine and cholesterol were dissolved in propylene glycol (see Table 1 in the Example for amounts of components). An oil-in-water emulsion was prepared by making an aqueous solution containing the antimicrobial agents methylparaben and propylparaben. The lipophilic components were mixed together, olive oil, glyceryl monostearate, cetyl alcohol, synthetic beeswax and homogenized with the aqueous phase in the presence of the Phospholipid EFA surfactant to form an oil-in-water emulsion stabilized with surfactant. The emulsion and an aqueous solution of 10 mg / ml leukotoxin were simultaneously added to the lipid components under effective conditions P1109 / 0OMX to form biphasic multilamellar lipid vesicles. The preparation was maintained at 40-45 ° C, mixed with a vortex mixer for 5 minutes. Biphasic lipid vesicles of approximately 0.5 to 10 μm were obtained. Transdermal patches were prepared as described in example 2. The reservoir of each patch was filled with 60 mg of a biphasic lipid vesicle suspension, where the lipid vesicles contained either 50 μm or 100 μm leukotoxin. The patches were fixed to mice, as described in Example 3 and left in place for three days. Three weeks later, the immunization was repeated, applying a new patch to each test mouse and leaving the patch in place for three days. Ten days after the second immunization on day 21, the mice were bled and the serum was analyzed for specific antibodies to leukotoxin, as set forth in Example 3. The results are presented in Figure 4 where the density is shown optical at 405 nm for a control patch, which is a patch containing placebo biphasic lipid vesicles and for patches containing either 50 μm or 100 μm of leukotoxin trapped in biphasic lipid vesicles. The results indicate that after immunization with 50 μm or 100 μm of leukotoxin transdermally to P1109 / 0OMX from the biphasic lipid vesicles can achieve significant levels of antibodies. Figure 5 shows the proliferative response of mass spleen cells isolated from control mice and immunized with leukotoxin using the present invention. Mass spleen cells were isolated from control and immunized mice and proliferation was measured by incubating the cells in the presence of 25 μg / ml leukotoxin. The results are expressed as a mean of the stimulation index of three independent experiments, as set forth in Example 4. Figure 6 is a graph showing the secretion of interleukin-4 by spleen cells in mass as determined by gout assay with enzyme-linked immunosorbent (ELISA). Secreted IL-4 was determined by spleen cells isolated from control mice and immunized with leukotoxin. After the immunization regimen, as described below, the spleen cells that were isolated were exposed to leukotoxin. IL-4 producing cells were identified by counting the number of secretory colonies of IL-4, as set forth in Example 5. In other studies conducted in support of the invention biphasic lipid vesicles containing egg lysozyme were prepared. chicken P1109 / 00MX and were transdermally delivered to animals. As described in Example 6, transdermal delivery devices were prepared which included chicken egg lysozyme trapped in lipid vesicles. Five different formulations of biphasic lipid vesicles were prepared, indicated by the numbers I-V. Each of the formulations contains a lipid vesicle lipid-forming lipid, hydrogenated phosphatidylcholine and cholesterol and are distinguished by the components of the oil-in-water emulsion. Each formulation includes 20 mg / ml hen egg lysozyme. As described in Example 7, the five different transdermal formulations were tested in vivo by attaching the devices to mice and measuring the immune response elicited. The test animals were immunized twice at an interval of 3 weeks by fixing a new patch for a 3-day dosing period at each of the two immunization time points. Ten days after the second immunization, the mice were sacrificed to evaluate the immune response to chicken egg lysozyme. Figure 7 is a bar graph showing the IgG response specific to chicken egg lysozyme in the serum of the test animals, determined by the optical density at 405 nm as described in Example 7. The data P1109 / 00MX show that all test formulations were effective in eliciting an immune response as evidenced by chicken IgG specific titers to chicken egg lysozyme in the serum of the test animals. Mice immunized with the lipid vesicle formulation no. V had the highest levels of IgG serum specific antigen. The chicken egg anti-lysozyme IgG response was first characterized by the IgGl subclass for all test formulations, as shown in Table 2.

Table 2 * The titles are expressed as the geometric mean of 5 individual mice. Figures 8A-8D are graphs showing the secretion of interleukin-4 and γ-interferon by mass spleen cells (Figures 8A-8B) and drained lymph node cells (Figures 8C- P1109 / 00MX 8D) after topical immunization in vitro of 50 μg of chicken egg lysozyme from each of the biphasic lipid vesicle formulations nos. I-V. The cells were cultured, in the manner described in example 8, in the presence of 20 μg / ml hen egg lysozyme and the frequency of interleukin-4 and interleukin-secreting cells in the lymph nodes and the spleen. it was evaluated by ELISPOT. As observed, antigenic stimulation in cells from these tissues showed a predominant response of interleukin-4 with respect to? -interferon. The effect of the route of administration was examined by administering 50 μg of chicken egg lysozyme trapped in biphasic lipid vesicles transdermally and subcutaneously. After immunization, the mouse serum was analyzed to determine the levels of chicken egg anti-lysozyme using ELISA. As seen in Figure 9, the specific antibody response to chicken egg lysozyme elicited by the transdermal route was comparable to that achieved by subcutaneous administration. The time and dose of immunizations can be determined by experienced technicians based on the known mechanisms of immune activation. Immune responses continue P1109 / 00MX characteristic immunization patterns with an immunogen. Initially, a latency phase is found between the time in which a subject is immunized and the logarithmic increase in antibody levels. An initial exposure to the immunogen leads to an increase in antibody levels, firstly IgM antibodies against antigenic epitopes in the immunogen, which decreases around week three post immunization. A subsequent immune stimulation, three or four weeks after the first exposure, leads to a vigorous immune response, where the primary class of antibodies is the IgG class. The secondary immune response is greater in intensity and longer in duration. In general, the immunization protocols for determining the appropriate response to an antigen are within the parameters known in the technical field. The dose of a particular immunogen will depend on its antigenic potential, size and diversity of epitopes, as well as the ability of the immunogen to stimulate the antigen-presenting cells. Examples of dose ranges for different classes of immunogens are found below in Table 3.

PX109 / 0OMX Table 3 In an immunization regimen that includes bacteria or viruses, attenuated forms of the immunogen are used to prevent infectious disease. Bacteria or viruses can be attenuated or inactivated by exposing them, for example, to elevated temperatures, denaturing chemical agents or by cultivating them under anaerobic conditions. Chemical modification of immunogens may include formulation, methylation, acylation or cross-linking of the immunogens with themselves or with other modifying agents. The immunogen does not have to be in pure form to be effective. To ensure the best chance of a specific epitope or epitopes and of a specific type of immune response (humoral versus cellular) the immunogen could be further purified P1109 / 00 X or synthesized. For example, small compounds that covalently bind proteins can be used to stimulate specific humoral responses to the epitope of choice. On the other hand, specific peptides could be sought to stimulate a particular class of T cells, such as cytotoxic cells or helper cells by presentation in the major histocompatibility complex (MHC) class I or class II, respectively, as is known to those in the art. technical field of the processing and presentation of antigens.

VI EXAMPLES The following examples illustrate the preparation and use of the device of the present invention. The examples are in no way intended to limit the scope of the invention.

Example 1 Preparation of Biphasic Lipid Vesicles Containing Leukotoxin A. Preparation of Lipid Components The lipid components, hydrogenated phosphatidylcholine (Phospholipon 90HMR, Natterman GmbH, Germany) and cholesterol, were mixed in the amounts shown in Table 1 with propylene glycol and they mixed with heating P1109 / 00MX between approximately 65 and 75 ° C.

B. Preparation of Oil Emulsion in Water An oil-in-water emulsion was prepared by mixing the surfactant linoleamidopropyl propylene glycol dimonium chloride (Phospholipid EFAM®, Mona Industries Inc., Patterson, NJ), methylparaben and propylparaben, in the amounts shown. presented in Table 1, in distilled water. In a separate vessel, the lipophilic components olive oil, glycerol monostearate, cetyl alcohol and synthetic beeswax are mixed together. The aqueous phase and the oil phase were mixed together in a high pressure homogenizer (H-5000 Laboratories Homogenizer Microfluidic Corp.) at 40 psi for 20 minutes. Visually, the emulsion is a milky solution that has the consistency of water.

C. Formation of Biphasic Lipid Vesicle The lipid components and the oil-in-water emulsion were mixed together by vortex or paddle mixing at 50-300 rpm.

P1109 / 00MX Table 1 Example 2 Preparation of Transdermal Device A transdermal device was prepared from the materials below in the following manner. A backing layer was die-cut from a Scotchpak ™ 1009 heat-sealable polyester film (3M Corporation, St Paul, MN), at a diameter of 18 mm. An annular ring having an outer diameter of 18 mm and an inner diameter of 10 mm of a pharmaceutical grade transfer adhesive (3M P1109 / 00MX Corporation, # 9871) was laminated to the backing layer. The release liner of the transfer adhesive was removed and a plastic foam ring (ARCare 7298 Medical Foam, Adhesive Research, Inc., Glen Rock, PA) with an outer diameter of 18 mm and an inner diameter of 10 mm was secured to the backing layer coated with adhesive. The edge of the ring that is not in contact with the support layer was coated with medical grade adhesive. The patch was filled with 60 mg of a biphasic lipid vesicle suspension, wherein the vesicles contained either 50 μg or 100 μg of leukotoxin and was prepared in the manner described in Example 1. After filling, a membrane from PeCapMR (Polyester HC7-51 from 3M Corporation), cut as a disc with an outer diameter of 12 mm, was laminated to the edge of the foam ring. An 18 mm disc release liner, 3M Corporation # 1022, was laminated on the side of the skin-oriented patch. The devices had an outer diameter of 18 mm with an active supply area of 7.8 mm2.

EXAMPLE 3 Transdermal Administration of Leukotoxin from Biphasic Lipid Vesicles The devices prepared as P1109 / 00HX described in Example 2 were tested in female Balb / c mice, 6 to 8 weeks of age (Animal Resource Center (University of Saskatchewan)). The mice were anesthetized by inhalation of halothane (MTC Pharmaceuticals, Cambridge, Ontario) and their hair was shaved from the back area with an electric shaver. The patches containing the vaccine formulation were applied to the shaved skin 24 hours after shaving and fastened with a plastic bandage. The patch was left in place for 3 days. The immunization was repeated on day 21 and the animals were bled 10 days later and the serum was analyzed to determine the specific antibody titers for leukotoxin, as follows. Specific antibody titers for leukotoxin were determined by ELISA. Plates of ninety-six cavities (Immulon 2; Dynatech Laboratories, Alexandria, VA) were coated with purified leukotoxin (0.05 μg / well) in a carbonate / bicarbonate buffer (pH 9.6). Plates were incubated overnight at 4 ° C and then washed 4 times in PBS-T containing 0.5% gelatin. Four-fold dilutions of mouse serum were prepared in PBS-T and distributed in 200 μl volumes. Plates were incubated for 1 hour and washed. The horse-biotin anti-mouse IgG conjugate (H & L) purified by affinity was used P1109 / 00MX (Vector Laboratories Inc., Toronto, Ontario)) at a dilution of 1 / 5,000 as the detection antibodies. After incubation for 2 hours and after four consecutive washes, a 1 / 10,000 dilution of streptavidin-alkaline phosphatase (BIO / CAN) in PBS-T (containing 0.5% gelatin) was added for 1 hour at room temperature . Di (Tris) p-nitrophenyl phosphate (PNPP, Sigma Chemical Co., St. Louis, MO) was used as the chromogenic substrate. The absorbance was read after 10 minutes at 405 nm (Bio-Rad, Richmond, CA). The results are presented in Figure 4, where the optical density at 405 nm is shown for the animals treated with a control patch (the patch deposit contained biphasic lipid vesicles with placebo) and for animals treated with patches containing 50 μg or 100 μg of leukotoxin trapped in biphasic lipid vesicles.

EXAMPLE 4 Proliferative Responses of Spleen Cells to Leukotoxin Spleens were aseptically removed from candid and immune mice and passed through a nylon mesh. The majority of the erythrocytes were removed in a lysis step of 1 minute using ammonium chloride buffered with TRIS (0.75%). Nucleated spleen cells were washed P1109 OOMX twice and subsequently resuspended in a culture medium. The culture medium consisted of AIM-V (Gibco-Life Technologies, Burlington, Canada), supplemented with 100 U / ml penicillin and 100 μg / ml streptomycin (Sigma Chemical Co.), 2mM L-glutamine (Gibco-Life Technologies), 100 μM non-essential amino acids (Gibco-Life Technologies), HEPES 1 mM (Gibco-Life Technologies) and 5 x 10"5 M 2-mercaptoethanol (Sigma Chemical Co.) A. Proliferation Two x 105 spleen cells were distributed in 100 μl volumes in the wells of the microtiter plates. Several concentrations of leukotoxin antigen in a volume of 100 μl were added to cavities in triplicate. After three days in culture, cells were labeled with [3 H] thymidine (Amersham, Oakville, Canada) at a concentration of 0.4 μCi / well. The cells were harvested 18 hours later and thymidine incorporation was assessed by scintillation counting. Proliferative responses, expressed as a stimulation index (counts per minute in the presence of antigen / counts per minute in the absence of antigen), are shown in Figure 5.

P1109 / 00MX Example 5 Quantification of Secretory Interleukin-4 Spleen Cells (IL-4) The specific ELISPOT assay for interleukin-4 was used as previously described (Czerkinsky, et al., 1988). Briefly, spleen cells were incubated in culture medium at 37 ° C and 5% C02 for 24-48 hours in the presence or absence of leukotoxin (0.5 μg / ml). The cells were washed twice and resuspended in the culture medium at an appropriate concentration. Nitrocellulose plates (Millipore Multiscreen-HA, Millipore, Bedford, MA) were coated for 2 hours at room temperature with 2 μg / ml mouse anti-interleukin-4 (IL-4) (11B11, Pharmingen, San Diego, CA ) diluted in 50 mM carbonate / bicarbonate buffer (pH 9.6). The unbound antibody was removed by washing once in phosphate buffered saline (PBS) containing 0.05% Tween 20 (Sigma Chemical Co.) (PBS-T) and three times with PBS. This was followed by a blocking step in the culture medium for 2 hours. The medium was decanted and 100 μl of each cell suspension was added to cavities in triplicate. After overnight incubation, the plates were washed in cold PBS-T to remove all cells. The ELISA sandwich for IL-4 was completed using mouse-specific biotinylated antibodies IL-4 (BVD5-24G2, Pharmingen) that were diluted to P1109 / 00MX a concentration of 3 μg / ml in BSA / 0.1% PBS. One hundred microliters of each suspension was added to the respective cavities and incubated for 2 to 4 hours at room temperature. The plates were washed three times in PBS-T. A 1/1000 dilution of streptavidin-alkaline phosphatase (BIO / CAN Scientific, Mississauga, Ontario, Canada) was prepared in BSA / PBS 0.1 and distributed in 100 μl volumes. Incubation was for 2 hours at room temperature followed by 8 consecutive washes in PBS. The substrate was prepared in the following manner: 5-bromo-4-chloro-3-indolyl phosphate (BCIP) (Sigma Chemical Co.) was dissolved in dimethylformamide (Sigma Chemical Co.) at a concentration between 14 mg / ml and 15 mg / ml. mg / ml and 1.5 mg were added to 10 ml of a 15 mM borate buffer (pH 9.8) containing 3 mg of nitro blue tetrazolium (NBT) (Sigma Chemical Co.). Magnesium chloride was added at a concentration of 5 mM. The substrate was filtered and added to the wells in 100 μl volumes and incubated at room temperature for 10 to 60 minutes. The plates were washed in distilled water and subsequently dried in air. The spots representing the location where IL-4 was secreted by spleen cells during nocturnal incubation were counted using a dissecting microscope. The results are plotted in Figure 6, where the values are expressed as the number of dots dyed, P1109 / 00MX positive for 5 x 10 cells. The results are expressed as the mean of the standard deviation of spleen cells assembled from four mice and reflect the activation of interleukin-4 secreting cells.

Interleukin-4, also known as B-cell growth factor-1, is a cytokine derived from T-cell that triggers the proliferation of B-cells primed with antigen. IL-4 not only stimulates the proliferation of B cells but also enhances the expression of MHC class II on the surface of antigen-presenting cells as well as the activation of the cytotoxic activity of cells T.

Example 6 Preparation of Transdermal Devices that Contain Chicken Egg Lysozyme Trapped in Biphasic Lipid Vesicles Chicken egg lysozyme (Sigma, St.

Louis, MO) was formulated into biphasic lipid vesicles according to the procedure of Example 1. Five different formulations of biphasic lipid vesicle, identified herein as formulations nos. I-V, each one included in the lipid bilayer of hydrogenated phosphatidylcholine (Phospholipon ™ 90H) and cholesterol from the lipid vesicle. The formulations are distinguished P1109 / 00MX mainly for the composition of the oil in water emulsion. Each formulation includes 20 mg / ml hen egg lysozyme. Transdermal patches were prepared as described in Example 2 and filled with 60 mg of one of the formulations, to obtain a dose of 100 μg of chicken egg lysozyme per patch.

Example 7 Transdermal Administration of Hen Egg Lysozyme Balb / c female mice between 6 and 8 weeks of age were provided by the Animal Resource Center (University of Saskatchewan). The mice were anesthetized by inhalation of halothane (MTC Pharmaceuticals, Cambridge, Ontario) and shaved on the back with an electric shaver. The patches containing different formulations of vaccines in lipid vesicle nos. I-V (Example 6) were applied to the shaved skin, fixed and secured with a plastic bandage. The animals were immunized twice at an interval of 3 weeks and sacrificed 10 days after the last immunization to evaluate the immune responses to chicken egg lysozyme. For each immunization, fresh patches were used and left for 3 days. Antibody titers were determined P1109 / 00MX specific for chicken egg lysozyme by ELISA assay. Ninety-six cavity plates (Immulon 2; Dynatech Laboratories Inc., Alexandria, VA) were coated with purified chicken egg lysozyme (0.05 μg / well) in a carbonate / bicarbonate buffer (pH 9.6). Plates were incubated overnight at 4 ° C and then washed 4 times in PBS-T containing 0.5% gelatin. Four-fold dilutions of mouse serum were prepared in PBS-T and distributed in 200 μl volumes. The plates were incubated for 1 hour and washed. The horse anti-mouse IgG-biotin conjugate (H & L) purified by affinity (Vector Laboratories Inc., Toronto, Ont.) Was used at a dilution of 1/5000 as the detection antibodies. After incubation for 2 hours and four consecutive washes, a 1 / 10,000 dilution of streptavidin-alkaline phosphatase (BIO / CAN) in PBS-T (containing 0.5% gelatin) was added for 1 hour at room temperature. Di (Tris) p-nitrophenyl phosphate (PNPP, Sigma) was used as the chromogenic substrate. The absorbance was read after 10 minutes at 405 nm (BIO-RAD, Richmond, CA). The results are shown in Figure 7.

P1109 / 00MX Example 8 Quantification of Secretory Lymphatic and Splenic Cells of IL-4 and? -IFN Spleens were aseptically removed from candid and immune mice and passed through a nylon mesh. The majority of the erythrocytes were removed in a lysis step of 1 minute using ammonium chloride buffered with TRIS (0.75%). Spleen cells were washed twice and subsequently resuspended in a culture medium. The culture medium consisted of AIM-V (Gibco, Life Technologies, Burlington, Canada), supplemented with 100 U / ml penicillin and 100 μg / ml streptomycin (Sigma Chemical Co., St. Louis, Missouri), 2 mM L-glutamine (Gibco, Life Technologies), 100 μM non-essential amino acids (Gibco, Life Technologies), 1 mM sodium pyruvate (Gibco, Life Technologies), 10 mM HEPES (Gibco-Life Technologies) and 5 x 10"5 M 2 -mercaptoethanol (Sigma Chemical Co.). an ELISPOT assay to quantify the frequency of interleukin-4 (IL-4) and? -interferon (? -IFN) secretory cells Briefly, spleen cells were incubated in a culture medium at 37 ° C and 5% C02 24 to 48 hours in the presence or absence of chicken egg lysozyme (2 μg / ml) The cells were washed twice and resuspended P1109 / 00MX at an appropriate concentration in a culture medium. Nitrocellulose plates (Millipore Multiscreen-HA; Millipore, Bedford, MA) were coated for 2 hours at room temperature with 2 μg / ml mouse anti-IL-4 (11B11) or mouse anti-γ-IFN (R4-). 6A2) (Pharmingen, San Diego, CA) diluted in 50 mM carbonate / bicarbonate buffer (pH 9.6). The unbound antibody was removed by washing once in buffered phosphate buffered saline (PBS) containing 0.05% Tween 20 (Sigma Chemical, Co.) (PBS-T) and three times with PBS. This was followed by a blocking step in a culture medium for 2 hours. The medium was decanted and 100 μl of each cell suspension was added to cavities in triplicate. After an overnight incubation, the plates were washed in cold PBS-T to remove all cells. Biotinylated antibodies specific for mouse IL-4 (BVD6-24G2) or? -IFN (XMG1.2) were diluted to a concentration of 3 μg / ml in BSA / 0.1% PBS. One hundred microliters of each suspension was added to the respective cavities and incubated for 2 to 4 hours at room temperature. The plates were washed three times in PBS-T. A 1/1000 dilution of streptavidin-alkaline phosphatase (BIO / CAN Scientific, Mississauga, Ont., Canada) was prepared in 0.1% BSA / PBS and distributed in 100 μl volumes. Incubation was for 2 hours at room temperature followed by 8 consecutive washes in PBS. The substrate P1109 / 00MX was prepared as follows: 5-bromo-4-chloro-3-indolyl phosphate (BCIP) (Sigma Chemical Co.) was dissolved in dimethylformamide (Sigma Chemical Co.) at a concentration of 15 mg / ml and 1.5 mg was added to 10 ml of a 15 mM borate buffer (pH 9.8) containing 3 mg of nitro blue tetrazolium (NBT) (Sigma Chemical Co.). Magnesium chloride was added at a concentration of 5 mM. The substrate was filtered and added to the wells in 100 μl volumes and incubated at room temperature for 10 to 60 minutes. The plates were washed in distilled water and subsequently dried in air. The spots were counted using a dissecting microscope. Values are expressed as the number of dyed, positive spots per 5 x 10 5 cells and are shown in Figures 8A-8D. Although the invention has been described with respect to particular embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the invention.

P1109 / 00MX

Claims (28)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property; A composition for the transdermal administration of an immunogen to elicit in a subject an immune response to the immunogen, comprising a suspension of biphasic lipid vesicles having a central core compartment containing an oil in water emulsion and an immunogen trapped in the biphasic lipid vesicles.
2. 2. The composition according to the claim 1, wherein the immunogen is selected from the group consisting of antigens derived from bacterial, viral, parasitic, plant and fungal origin.
3. 3. The composition according to claim 1, wherein the immunogen is effective to elicit a humoral immune response.
4. 4. The composition according to claim 1, wherein the immunogen is effective to elicit a cell-mediated immune response.
5. 5. The composition according to the claim 1, which also includes an auxiliary trapped in the lipid vesicles.
6. 6. The composition according to the claim P1109 OOMX 1, wherein the suspension of lipid vesicles also includes a cutaneous permeation enhancer.
7. The composition according to claim 6, wherein the permeation enhancer is selected from the group consisting of fatty acylated amino acids and unsaturated fatty acids.
8. 8. A method for eliciting in a subject an immune response to an immunogen, comprising transdermally administering to the subject, a dose of the immunogen, the immunogen entrapped in the biphasic lipid vesicles having a central core compartment containing an oil in water emulsion .
9. The method according to claim 8, wherein the immunogen is an antigen of bacterial, viral or fungal origin.
10. The method according to claim 8, wherein the immunogen is effective to elicit a humoral immune response.
11. The method according to claim 8, wherein the immunogen is effective to elicit a cell-mediated immune response.
12. The method according to claim 8, further comprising an auxiliary entrapped in the lipid vesicles.
13. The method according to claim 8, wherein the suspension of lipid vesicles is contained in a reservoir adapted to retain it in P1109 OOMX the same.
14. The method according to claim 13, wherein the reservoir is defined by an impermeable support member and an effective membrane for use that allows the passage of the lipid vesicles from the reservoir.
15. 15. The method according to claim 8, wherein the suspension of lipid vesicles further includes a permeation enhancer.
16. 16. The method according to claim 15, wherein the permeation enhancer is selected from the group consisting of fatty acylated amino acids and unsaturated fatty acids.
17. 17. A method for transdermally administering an immunogen to a subject, comprising applying a device to the skin of the subject, the device including: (i) a suspension of lipid vesicles formed by mixing an oil-in-water emulsion with lipids vesicle formers composed of (a) an outer lipid bilayer membrane composed of the vesicle-forming lipids, (b) a central core compartment containing the oil in water emulsion and (c) trapped in the vesicles, a dose of effective immunogen to elicit an immune response; (ii) a reservoir adapted to retain the suspension of lipid vesicles and adapted for P1109 / 00MX release the lipid vesicles therefrom; and (iii) means for attaching the device to a subject for the transdermal administration of the immunogen.
18. 18. The method according to claim 17, wherein the reservoir is defined by an impermeable support member and an effective membrane for use that allows passage of the lipid vesicles from the reservoir.
19. 19. The method according to claim 17, wherein the suspension of lipid vesicles includes a permeation enhancer.
20. The method according to claim 19, wherein the permeation enhancer is selected from the group consisting of fatty acylated amino acids and unsaturated fatty acids.
21. The method according to claim 17, wherein the means for fixing is an adhesive layer adjacent to the membrane.
22. 22. The method according to claim 17, further comprising an auxiliary, entrapped in the lipid vesicles.
23. 23. A device for the transdermal administration of an immunogen, comprising a suspension of lipid vesicles formed by mixing an oil-in-water emulsion with vesicle-forming lipids, the vesicles composed of (i) an outer lipid bilayer membrane composed of P1109 / 00MX the vesicle-forming lipids, (ii) a core nuclear compartment containing the oil in water emulsion and (iii) trapped in the vesicles a dose of an effective immunogen to elicit an immune response; a reservoir adapted to retain the suspension and adapted to release the lipid vesicles therefrom; and means for attaching the device to a subject for the transdermal administration of the immunogen.
24. 24. The device according to claim 23, wherein the reservoir is defined by an impermeable support member and a membrane for use that allows passage of the lipid vesicles from the reservoir.
25. 25. The device according to claim 23, wherein the suspension of lipid vesicles includes a permeation enhancer.
26. 26. The device according to claim 23, wherein the permeation enhancer is selected from the group consisting of fatty acylated amino acids and unsaturated fatty acids.
27. 27. The device according to claim 23, wherein the means for fixing is an adhesive layer adjacent to the membrane.
28. 28. The device according to claim 23, further including an auxiliary, trapped in the lipid vesicles. P1109 / 00MX