JP2011020978A - Immunoenhancing agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an immunoenhancing agent acting on an intestinal immune system. <P>SOLUTION: The immunoenhancing agent contains palmitic acid, its physiologically allowable salt or its ester as an active component. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an immunopotentiator. More specifically, the present invention relates to an immunopotentiator comprising palmitic acid as an active ingredient, and particularly having an action of enhancing immunity in the intestinal tract.

  The intestinal mucosal epithelium is in contact with many intestinal bacteria and dietary components, and is the place where antigens first invade.Therefore, the intestinal tract collects the most lymphocytes in the body, and a large amount of immunoglobulin A ( It has evolved to produce (IgA) (hereinafter, this immune system may be referred to as “intestinal immune system”). In the intestinal tract immune system, immunocompetent cells peculiar to the intestinal tract immune system are deployed in addition to immunocompetent cells having the same properties as the systemic immune system such as the spleen. From previous studies, in the intestinal tract immune system, in addition to cell-cell interactions in vivo, immune control is performed through interactions with intestinal environmental factors such as intestinal bacteria and dietary components. The molecular basis is gradually becoming clear.

  For example, it has been clarified that sphingosine monophosphate is involved in the regulation of intestinal IgA production and migration of lymphocytes between epithelial cells among lipid mediators that are involved in bioregulation and one of the sources of dietary lipids. (J. Immunol., 180, pp.5335-5343, 2008; Blood, 109, pp.3749-3756, 2007; Blood, 111, pp.4646-4652, 2008; J. Exp. Med., 204, pp.2335-2348, 2007; J. Immunol., 179, pp.1577-1585, 2007).

  On the other hand, it has been suggested that the balance of dietary lipids linoleic acid and linolenic acid affects immune responses including inflammatory reactions (Biotechnol. J., 1, pp. 420-439, 2006) However, little is known about the immunological effects of other dietary lipids. In particular, the lipids that regulate the production of secretory IgA, a biological defense molecule in the intestinal tract, have not been elucidated at all.

  The main production pathway of sphingosine 1-phosphate is palmitoyl CoA derived from palmitic acid, a C16 saturated linear fatty acid, and sphinganine produced from palmitoyl CoA and serine is sequentially converted to ceramide and sphingosine 1 Although the pathway through which phosphoric acid is produced has been elucidated, there is no previous report that palmitic acid has an effect of controlling the immune system, particularly the intestinal tract immune system.

J. Immunol., 180, pp.5335-5343, 2008 Blood, 109, pp.3749-3756, 2007 Blood, 111, pp.4646-4652, 2008 J. Exp. Med., 204, pp.2335-2348, 2007 J. Immunol., 179, pp.1577-1585, 2007 Biotechnol. J., 1, pp. 420-439, 2006

  An object of the present invention is to provide an immunopotentiator, and more specifically, it is an object of the present invention to provide an immunopotentiator that acts particularly on the intestinal tract immune system.

  In order to solve the above-mentioned problems, the present inventors have conducted intensive studies for the purpose of examining the immunoregulatory effect of fatty acids contained in dietary oil and identifying lipids having an immunoregulatory function. As a result, it was found that palmitic acid, which is a dietary oil, has an intestinal IgA production enhancing action and is useful as an intestinal immune activity enhancing agent. The present invention has been completed based on the above findings.

That is, the present invention provides an immunopotentiator comprising palmitic acid, a physiologically acceptable salt thereof, or an ester thereof as an active ingredient.
According to a preferred embodiment of the present invention, there is provided an intestinal immunity enhancing agent comprising palmitic acid, a physiologically acceptable salt thereof, or an ester thereof as an active ingredient.

  According to another preferred embodiment, the above immunopotentiator using palm oil as an ester of palmitic acid; the above immunopotentiator used for the prevention and / or treatment of intestinal infections; the above used as an immunoadjuvant during oral vaccination An immunopotentiator is provided.

From another aspect, the present invention provides a method for enhancing immunity, preferably intestinal immunity, in mammals, including humans, wherein a required amount of palmitic acid, a physiologically acceptable salt thereof, or an ester thereof is administered. There is provided a method comprising the steps of:
From yet another aspect, the present invention provides the use of palmitic acid, a physiologically acceptable salt thereof, or an ester thereof for the manufacture of the above-described immunopotentiator.

  The immunopotentiator provided by the present invention has an effect of enhancing IgA production particularly in the intestine, preferably in the large intestine by acting on the intestinal tract immune system. Since the immunopotentiator of the present invention increases the amount of IgA in the intestinal tract, it can enhance the biological defense function through the intestinal tract immune system. In addition, since this immunopotentiating effect is strongly exerted particularly in the large intestine, in addition to pathogenic Escherichia coli such as O-157, intestinal tracts in vaccines for oral administration against intestinal infections such as Salmonella, cholera, rotavirus, or norovirus. It is also useful as an internal immune adjuvant. Furthermore, due to the common mucosal immune system (CMIS: phenomenon in which the immune response induced by oral immunity is enhanced in other mucosal tissues such as the respiratory tract and urinary tract), the immunity of the present invention containing palmitic acid is also included. Enhancers are also useful as immunoadjuvants for oral vaccines against respiratory infections such as influenza virus and S. pneumoniae, as well as genital infections such as HIV and chlamydia.

FIG. 3 is a view showing the results of measuring the amount of IgA in feces of mice bred with a feed (PA feed) in which 1.5% palmitic acid (PA) is added to 4% soybean oil (SOybean) by ELISA. Mock is the control, and PA is the result when reared on PA diet. It is the figure which showed the FACS analysis image (the upper stage is a small intestine and the lower stage is a large intestine) of an intestinal tract. It is the figure which showed the result of having measured the amount of IgA in the stool of the mouse | mouth raised with the feed which added 1.5% palmitic acid to 4% linseed oil (Linseed) by ELISA method. Mock is the control, and PA is the result when fed with palmitate-added feed. It is the figure which showed the result of having measured the amount of IgA in the stool of the mouse | mouth raised with the feed containing palm oil 4% by ELISA method. Soy is a control using only soybean oil, and Palm is a result of breeding with a feed containing palm oil. Mice bred with PA diet were orally immunized with chicken ovalbumin and cholera toxin, and the OVA-specific IgA antibody titer was measured by ELISA (left figure), and the number of OVA-specific IgA-producing cells was measured by ELISPOT. It is the figure which showed the result (right figure). Mock is the control, and PA is the result when reared on PA diet.

  The immunopotentiator of the present invention is characterized by containing palmitic acid, a physiologically acceptable salt thereof, or an ester thereof as an active ingredient. As used herein, the term “immunity enhancer” has the effect of enhancing immunity in mammals including humans, and is used for the prevention and / or treatment of diseases of mammals including humans, such as intestinal infections. Although it means a useful medicine, the terminology of the medicine used in this specification includes, for example, food for specified health use approved by the Ministry of Health, Labor and Welfare as having effectiveness based on scientific evidence for maintaining and promoting health. Are also included. As used herein, the term “immunopotentiator” or “medicament” should be construed in the broadest sense and should not be construed as limiting in any way.

  Palmitic acid (hexadecanoic acid) is a straight-chain saturated fatty acid having 16 carbon atoms and is a readily available substance. As palmitic acid, for example, palmitic acid purified to a purity of 50% or more, preferably 70% or more, more preferably 80% or more, particularly preferably 90% or more can be used. Can also be used as an active ingredient of the immunopotentiator of the present invention. Examples of physiologically acceptable salts of palmitic acid include, but are not limited to, metal salts such as sodium salts, potassium salts, and magnesium salts.

  As an ester of palmitic acid, an ester with a monoalcohol compound, an ester with a diol compound, an ester with a triol compound, or the like can be used. More specifically, alkyl esters such as methyl palmitate and sterol esters such as sterol palmitate; glycol esters such as monoacyl glycol or diacyl glycol containing at least one palmitoyl group; or at least one palmitoyl Examples thereof include, but are not limited to, glycerol esters such as monoacylglycerol, diacylglycerol, or triacylglycerol containing a group. When glycol esters or glycerol esters containing at least one palmitoyl group are used, they may contain an acyl residue other than the palmitoyl group. In this case, the acyl residue may be a linear or branched acyl group and / or a saturated or unsaturated acyl group.

  As the glycerol ester, for example, a substance classified as a simple lipid can be used. A simple lipid as a purified single substance may be used, but for example, a mixture of several glycerol esters may be used. As such a mixture, an edible oil containing palmitic acid as a fatty acid constituting triacylglycerol can also be used. For example, since palm oil contains a large amount of triacylglycerol containing palmitic acid as a constituent lipid, it is also preferable to use palm oil as an ester of palmitic acid. These esters can be rapidly hydrolyzed by an enzyme such as lipase in the intestinal tract to release free palmitic acid, and the released palmitic acid acts as an immunopotentiator.

  The immune enhancer of the present invention has an action of acting on the intestinal tract immune system to enhance the production of IgA in the intestinal tract. The immunopotentiator of the present invention enhances the biological defense mechanism in the intestinal tract, particularly the biological defense mechanism in the large intestine, and inoculates an oral vaccine effective against, for example, pathogenic Escherichia coli, Salmonella, cholera, rotavirus, or norovirus. A high vaccine induction effect can be achieved by using it as an immune adjuvant sometimes. Needless to say, such an adjuvant is also an embodiment of the immunopotentiator of the present invention. By enhancing intestinal immunity using the immunopotentiator of the present invention, it is possible to enhance the protective effect against infection from intestinal microflora, and to achieve prevention and / or treatment of intestinal infections. . For example, it can be administered prophylactically in anticipation of an infection-protecting action against pathogenic E. coli O-157, Norovirus, and the like.

  As the immunopotentiator of the present invention, palmitic acid, which is an active ingredient, physiologically acceptable salts thereof, or esters thereof may be used as they are, but appropriate pharmaceutical additives such as excipients, stabilization It is preferable to prepare and administer the composition in the form of one or more agents, antioxidants, preservatives, solubilizers, oily solvents and the like. Although the administration form of the immunopotentiator of the present invention is not particularly limited, it is usually desirable to administer it orally. For example, it can be prepared as a preparation for oral administration in the form of hard capsules, soft capsules, tablets, granules, powders, etc., but is not limited thereto. When palm oil or the like is used as the palmitic acid ester, it can be prepared and administered as a soft capsule, for example. For example, when provided as a health food, for example, edible oils (eg, soybean oil, rapeseed oil, corn oil, cottonseed oil, sesame oil, olive oil, palm oil, etc., as well as diglycerides and medium chain fatty acid triglycerides) Palmitic acid, physiologically acceptable salts thereof, or esters thereof (for example, palm oil) can be added to edible oils.

  The dose of the immunopotentiator of the present invention is not particularly limited, but can be appropriately selected, for example, from the range of about 1 mg to 10 g per day for adults, the purpose of infection protection or adjuvant action, body weight, age, sex, etc. It can be appropriately increased or decreased depending on conditions such as the presence or absence of the underlying disease. Several doses per day may be administered.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, the scope of the present invention is not limited to a following example.
Example 1
6-week-old mice (female Balb / c mice, 6-week-old, average body weight) with a diet containing 4% soybean oil and 1.5% palmitic acid (free form fatty acid, Wako Pure Chemical Industries, Ltd.) 15 g) was bred, and the amount of IgA in stool was measured by ELISA. The results are shown in Figure 1. The intake of PA food increased the amount of IgA in feces about 3 times. FIG. 2 shows a FACS analysis image of the intestinal tract (the upper stage is the small intestine and the lower stage is the large intestine). IgA + and CD138 + IgA-producing cells (CD138-positive IgA plasma cells) increased in the large intestine of mice ingested with PA diet for 6 weeks. This fecal IgA production enhancement effect was also observed when 1.5% palmitic acid was added to linseed oil (FIG. 3).

Example 2
A feed containing 4% palm oil (Kaneda Co., Ltd.) containing a large amount of palmitic acid as a lipid component instead of soybean oil was prepared, and mice were raised for 6 weeks in the same manner as in Example 1. As a result, fecal IgA production was enhanced in the same manner as in Example 1 when palmitic acid was added at 1.5%. The results are shown in FIG.

Example 3
Mice bred on PA diet for 6 weeks were orally immunized with chicken ovalbumin (OVA, 1 mg) three times a week together with cholera toxin (10 μg) as a mucosal adjuvant. Feces were collected one week after the final immunization, and the OVA-specific IgA antibody titer was measured by ELISA (FIG. 5, left figure). At the same time, mononuclear cells were collected from the small intestine and large intestine, and the number of OVA-specific IgA producing cells was measured by the ELISPOT method (FIG. 5, right figure). As a result, in mice fed with PA food, the production of fecal OVA-specific IgA was enhanced and the increase of OVA-specific IgA-producing cells in the large intestine was observed.

Claims (5)

An immunopotentiator comprising palmitic acid, a physiologically acceptable salt thereof, or an ester thereof as an active ingredient. The immune enhancer according to claim 1, which is an intestinal immunity enhancer. The immunopotentiator according to claim 1 or 2, wherein palm oil is used as an ester of palmitic acid. The immunopotentiator according to any one of claims 1 to 3, which is used for prevention and / or treatment of intestinal infections. The immunopotentiator according to any one of claims 1 to 3, which is used as an immune adjuvant at the time of inoculation with an oral vaccine.

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