JP4889206B2 - Macrophage activator having IL-12 production inducing activity - Google Patents

Description

  The present invention relates to a macrophage activator comprising an acidic mucopolysaccharide produced by marine bacteria as an active ingredient. More specifically, the present invention relates to a macrophage activator having interleukin 12 (hereinafter referred to as “IL-12”) production-inducing activity.

  IL-12 was discovered as a cytokine having an action of activating natural killer cells (NK cells), and activities such as increased cellular immune activity, macrophage activation, and IgE production suppression have been confirmed (Allergy Clin. Immunol. 107, 9-18, 2001). Therefore, it is expected to be applied as a therapeutic agent for allergies, cancers, viral diseases and the like. IL-12 is important for antitumor expression by activating NK cells, NKT cells, etc., and is an interferon that strongly activates killer T cells that attack cancer and enhances cellular immunity. Activates the production and function of γ. On the other hand, IL-12 is expected to have an effect of suppressing the onset of allergies and autoimmune diseases by having an action of inducing the immune balance (Th1 / Th2) of the living body to the Th1 side.

In addition, research on macrophages has recently become active, and the role of macrophages in immune responses has attracted attention. For example, macrophages are originally defined as phagocytic cells, but they are not limited to primordial phagocytic cells, but are activated to acquire damage to cancer cells and release lymphocytes by releasing various cytokines. It has become clear that it is deeply involved in the immune system, such as in Conventionally, substances that activate various macrophages such as nucleic acids, herbal extracts, lipopolysaccharides, and other polysaccharides have been proposed. Examples include nucleic acid compositions (Patent Document 1), seaweed extract-derived compositions (Patent Document 2), lactic acid bacteria preparations (Patent Document 3), and the like.
JP 2001-314172 A JP 2002-193828 A Japanese Patent Laid-Open No. 10-167972

However, in the invention according to Patent Document 1, the types of ingredients and the blending ratio are not specified, and the IL-12 production amount is weak. The invention according to Patent Document 2 is mainly composed of neoagaro-oligosaccharide and its desulfurized neutral sugar, and also contains indigestible polysaccharide, lectin, nucleic acid, ash, etc. having a higher degree of polymerization. It was something to do. Furthermore, in the invention concerning patent document 3, it consisted of the microbial cell of lactic acid bacteria, or its processed material. That is, in any of the inventions according to Patent Documents 1 to 3, the active main body is not specified, and as it is, it is insufficient in terms of safety and efficacy, and practically difficult to apply as a food or a medicine. Therefore, a macrophage activator having both safety and efficacy has been demanded.
In addition, since there are few reports on macrophage activation accompanied with IL-12 production induction, new means for inducing macrophage activation and IL-12 production have been demanded.

A first aspect of the present invention is an including immunostimulants salt marine bacteria is acidic mucopolysaccharide or a physiologically acceptable to produce as an active ingredient,
Interleukin 12 production-inducing activity, acidic mucopolysaccharide is a compound represented by the following structural formula (I), and the compound represented by the structural formula (I) is based on the total weight of the macrophage activator. The gist is a macrophage activator which is contained at least 0.001% by weight.
A second aspect of the present invention is a macrophage activator comprising an acidic mucopolysaccharide produced by marine bacteria or a physiologically acceptable salt thereof as an active ingredient,
Interleukin 12 production-inducing activity, acidic mucopolysaccharide is a compound represented by the following structural formula (I), and the compound represented by the structural formula (I) is based on the total weight of the macrophage activator. The gist is an immunostimulant contained at least 0.001% by weight.

(上記の構造式において、GalNAcpはピラノース型N-アセチルガラクトサミン残基を、GlcUApはピラノース型グルクロン酸残基を、DはD型を、LはL型を、Pyrはピルビン酸を、ｎは繰り返しの数をそれぞれ表す。)

(In the above structural formula, GalNAcp is a pyranose-type N-acetylgalactosamine residue, GlcUAp is a pyranose-type glucuronic acid residue, D is a D-type, L is an L-type, Pyr is pyruvic acid, and n is a repeat. Represents the number of each.)

According to the present invention, a macrophage activator having both safety and efficacy is provided.
Also provided are new means of inducing macrophage activation and IL-12 production.

Hereinafter, the present invention will be described with reference to embodiments, but it goes without saying that the present invention is not limited to the following embodiments.
(Macrophage activator)
The present inventors searched using a mouse-derived macrophage-like cell line in order to find a substance having an excellent macrophage activation effect. As a result, it was found that acidic mucopolysaccharides produced by marine bacteria have macrophage activity. Further, the present inventors have found that the acidic mucopolysaccharide induces IL-12 production and has extremely low cytotoxicity and is extremely effective as an immunostimulating agent. That is, this invention is completed based on the said knowledge, and relates to the macrophage activator which contains the acidic mucopolysaccharide which marine bacteria produce as an active ingredient.
As such an acidic mucopolysaccharide, it is preferable to use an acidic mucopolysaccharide isolated and purified from a culture of the marine bacterium Pseudomonas sp. WAK-1 (Pseudomonas sp. WAK-1) or a mutant thereof [Mazda (M Matsuda) et al .: Fisheries Science, 63, 983-988 (1997)]. These “acidic mucopolysaccharides” are simply referred to as “WAK-1-A” or “polysaccharide WAK-1-A” in the present specification. The polysaccharide WAK-1-A is already a known substance and is a compound represented by the above structural formula (I) [M. Matsuda et al .: 1997]. In addition, the above WAK-1-A is known to have a cartilage cultured cell proliferation promoting effect, but it has been reported that it was used as an inducer of macrophage activation and cytokines, particularly IL-12 production inducer. Is not known at all.
Since WAK-1-A can promote macrophage activation and IL-12 production induction, it can provide a useful material in the fields of medicine, health food and cosmetics where an immune effect is expected. . It is particularly effective for the prevention or treatment of allergies such as hay fever and atopic dermatitis, autoimmune diseases such as rheumatism, and cancer.

  WAK-1-A has an ability to induce tumor necrosis factor (TNF-α) associated with macrophage activation, for example, as an immunostimulatory activity. This activity suggests that WAK-1-A has antitumor properties via the immune system.

(Immunostimulatory composition)
When using the macrophage activator as an immunostimulatory composition, the active ingredient WAK-1-A and various ingredients commonly used in pharmaceuticals or foods, such as oils, moisturizers, preservatives, bactericides, colors An agent, powder, a fragrance, a thickener, a buffering agent, and the like are prepared by appropriately blending with the dosage form as long as the effects of the present invention are not impaired. In addition, when WAK-1-A is added to the immunostimulatory composition, it is preferable to consider the macrophage activation and IL-12 production-inducing action of these compounds. Add about 0.001% by weight or more, preferably about 0.01 to 20.0% by weight. It is not always necessary to isolate and use the active ingredient, and a crude product containing the compound of the present invention can be used as long as the effects of the present invention are not impaired. The dosage form of the immunostimulatory composition is arbitrary, for example, a solubilizing system such as a capsule, tablet, pill, granule or drink, an emulsifying system such as an emulsion or cream, or a dosage form such as an ointment or dispersion. Can take.
The immunostimulant exhibits an excellent immunostimulatory effect and has both stability and high safety. For example, the occurrence of cancer, viral disease, atopic dermatitis and the like can be prevented. It can also be used to treat cancers that have already developed, viral diseases, and atopic dermatitis.

(Active ingredient)
As WAK-1-A, those prepared by various methods can be used as long as they are purified to the extent that they can be used as pharmaceuticals. Various methods are known as methods for preparing WAK-1-A. For example, polysaccharides can be produced by culturing marine microorganisms as sucrose as a carbon source, seawater containing peptone as a nitrogen source and seawater containing yeast extract in agar, collected and purified [Mazda (M Matsuda) et al., Japanese Journal of Fisheries Science, 58, 1735-1741 (1992)]. In addition, when producing a polysaccharide by culturing marine microorganisms in a predetermined medium, it may be based on a polysaccharide production method characterized by culturing the microorganism in a medium containing sodium chloride at a higher concentration than seawater (special (See Kaikai 2003-274928). More specifically, for example, in agar plate culture, Pseudomonas sp. WAK-1 (Pseudomonas sp. In a medium in which a polysaccharide production seawater medium containing sucrose as a carbon source, peptone as a nitrogen source, and yeast extract is solidified with agar. It can be obtained by culturing a WAK-1) strain or a mutant thereof, and separating and purifying WAK-1-A from the mucilage produced on the agar plate.

  When using a sodium chloride-containing medium having a higher concentration than seawater, it contains 5.5 to 8.0% (W / V) sodium chloride as an inorganic salt, sucrose as a carbon source, peptone as a nitrogen source, and yeast extract. In a polysaccharide production medium, Pseudomonas sp. WAK-1 (Pseudomonas sp. WAK-1) strain or a mutant thereof is subjected to mild agitation, substantially stationary conditions and weak anaerobic conditions. By culturing, WAK-1-A can be selectively obtained in high yield.

  As a basic medium for culturing microorganisms producing WAK-1-A, microorganisms capable of producing polysaccharides can grow, and at least a carbon source, a nitrogen source, various inorganic salts, and trace elements are contained. What contains an appropriate amount is used. More preferably, a culture medium that can grow microorganisms belonging to the genus Pseudomonas is used as the basic medium. Examples of the carbon source include sugars such as glucose, fructose, galactose, and sucrose, and molasses and molasses. One or two or more carbon sources can be used alone or in combination. Nitrogen sources include compounds such as nitrates and ammonium salts, and natural products such as peptone, yeast extract and amino acids. One or two or more nitrogen sources can be used alone or in combination. Examples of the inorganic salt include phosphate, magnesium salt, potassium salt and the like. One or two or more inorganic salts can be used alone or in combination. In particular, when the sodium chloride concentration is 5.5 to 8.0% (W / V), the production of polysaccharides is significantly improved. In the case of a solid medium, agar is used.

  The culture conditions other than the sodium chloride concentration of the culture medium, for example, the culture medium used, the pH of the culture medium, the additive to the culture medium, the culture temperature, etc., can be the same as those usually used for culturing microorganisms.

  The microorganism used for the production of WAK-1-A can be used without particular limitation as long as it can produce polysaccharides. Preferably, marine microorganisms, more preferably marine microorganisms capable of producing WAK-1-A are used. Specific examples include marine Pseudomonas bacteria, and more specifically, Pseudomonas sp. WAK-1 strains or mutants thereof. This strain is a marine bacterium isolated from the surface of seaweed by the present inventors in the Seto Inland Sea, and its taxonomic characteristics are described in the Journal of the Japanese Fisheries Society [M.Matsuda et al .: 1992]. .

  The culture conditions are not limited as long as the pH during culture is a range in which microorganisms can grow and produce polysaccharides, but a pH in the range of 6 to 7.5 is usually preferable. The culture temperature is not limited as long as microorganisms grow and produce polysaccharides, but a range of 25 ° C. to 30 ° C. is good for producing polysaccharides. The culture period varies depending on the culture pH and temperature, but usually 2 to 7 days is appropriate.

  By culturing the microorganisms using the above-mentioned medium and microorganisms using a conventional method, the active ingredient WAK-1-A can be efficiently produced.

The WAK-1-A has a molar ratio of constituent sugars of N-acetyl-D-galactosamine: D-glucuronic acid: N-acetyl-L-galactosamine: pyruvic acid 2: 1: 1: 1 (molar concentration ratio). Thus, it is preferable that the average molecular weight measured by gel filtration chromatography is 1,000,000 to 1,500,000 with pullulan as a standard. Specifically, high performance liquid chromatography (manufactured by Shimadzu) using Asahipak GFA-7M (manufactured by Showa Denko) as a column, 0.1N NaCl as the mobile phase, pullulan having a known molecular weight (Shodex STANDARD KIT P-82, It can be measured using a molecular weight retention time standard curve prepared as a standard sample. Cellulose acetate membrane electrophoresis or high performance liquid chromatography can be used for the analysis of the constituent components. For the analysis of this component, a polysaccharide was hydrolyzed with 2M trifluoroacetic acid (TFA) or 4N-HCl at 100 ° C. for 12 hours, and TFA or HCl was removed with a rotary evaporator as a sample. Analyzes of natural sugars, uronic acids, organic acids and amino sugars. In particular, the analysis of uronic acid is performed by analyzing the neutral sugar by hydrolysis after reduction of the carboxyl group of the polysaccharide. In addition to this, an enzymatic method can be used for analysis of organic acids.

(Method for producing active ingredient)
Next, a method for producing WAK-1-A as an active ingredient will be described with reference to a preferred embodiment. Needless to say, the production method of WAK-1-A is not limited to the following production method.
A method for producing WAK-1-A as a preferred embodiment includes (a) a step of preparing a medium containing high concentration sodium chloride, and (b) a step of culturing a microorganism in the medium to produce a polysaccharide. And (c) a step of extracting and collecting the produced WAK-1-A, an optional step (d) a step of separating and collecting the produced WAK-1-A, and (e) a gentle stirring. Or a step of culturing under weak anaerobic conditions.

Subsequently, the above embodiment will be described in detail for each step.
(A) Step of preparing a medium containing high concentration sodium chloride First, a medium containing sodium chloride having a higher concentration than seawater is prepared. In this case, it is preferable to prepare so that the sodium chloride concentration in the medium is 5.5 to 8.0% (W / V). More preferably, the above-described medium of the present invention is used, and in that case, it is more preferable to use sucrose as a carbon source, peptone as a nitrogen source, and yeast extract.
(B) Step of culturing microorganisms in the above-mentioned medium to produce polysaccharides The target polysaccharide is produced by culturing microorganisms using the medium prepared as described above. In order to obtain it, it is preferable to use the genus Pseudomonas as a microorganism. More preferably, Pseudomonas sp. WAK-1 strain or a mutant thereof is preferably used. By using Pseudomonas sp. WAK-1 strain or a mutant thereof as a microorganism, WAK-1-A can be produced efficiently.

(上記の構造式において、GalNAcpはピラノース型N-アセチルガラクトサミン残基を、GlcUApはピラノース型グルクロン酸残基を、DはD型を、LはL型を、Pyrはピルビン酸を、ｎは繰り返しの数をそれぞれ表す。)
そして、以下に説明する抽出・回収工程を経ることにより高純度のWAK-1-Aを高収率で得ることが可能となる。 Here, WAK-1-A has the following structural units.

(In the above structural formula, GalNAcp is a pyranose-type N-acetylgalactosamine residue, GlcUAp is a pyranose-type glucuronic acid residue, D is a D-type, L is an L-type, Pyr is pyruvic acid, and n is a repeat. Represents the number of each.)
And it becomes possible to obtain highly purified WAK-1-A with a high yield through the extraction and collection | recovery process demonstrated below.

(C) Step of developing and recovering the produced predetermined polysaccharide As a method for extracting WAK-1-A from the culture solution obtained by the above production method, a conventionally known method can be used. For example, after sterilizing the culture solution as it is or at a high temperature, the microbial cells are removed by centrifugation, and after adding or concentrating this, add 2-3 times the amount of ethanol, isopropanol, or acetone, This causes precipitation. This precipitate is dissolved again in water or 1 to 15% by weight sodium chloride solution, and then precipitation with alcohol or the like is repeated 2-3 times, dialyzed with water, and using a spray dryer or a freeze dryer. WAK-1-A is obtained by drying. In addition, electrodialysis and ultrafiltration can be used. For further purification, various chromatographies such as ion exchange and gel filtration, precipitation or salting out with a quaternary ammonium salt, and the like can be used.

  When removing the cells from the culture solution, a membrane separation apparatus equipped with a hollow fiber module having a pore diameter of 0.2 μm can be used.

(D) Step of separating / recovering the produced predetermined polysaccharide The polysaccharide can be extracted / recovered by the above-described extraction / recovery method. Bacteria belonging to the genus Pseudomonas and capable of producing WAK-1-A disclosed in Japanese Patent Application Laid-Open No. 2002-065292 are cultured under a substantially stationary condition in a liquid medium. A WAK-1-A separation method characterized by producing and accumulating -1-A and collecting it may be used in combination. By using such a separation method in combination, WAK-1-A can be efficiently separated and recovered.

(E) Step of culturing under weak anaerobic conditions From the above findings, the present invention may further include (e) a step of culturing under gentle stirring or weak anaerobic conditions as an optional step.

  Thus, WAK-1-A is produced and recovered. WAK-1-A obtained by the present invention can be used for various applications without particular limitation, but is suitable as a macrophage activation and cytokine production inducer, preferably as a macrophage activation and IL-12 production inducer. Used for.

  In the present invention, at least 0.001% by weight or more, preferably 0.01 to 20% by weight of WAK-1-A is added to the macrophage activator as an active ingredient. This macrophage activator containing WAK-1-A as an active ingredient has IL-12 production-inducing activity. Such macrophage activators can be used in appropriate forms such as powders, emulsions, capsules, tablets, pills, granules, and drinks by using commonly used pharmaceuticals, skin external preparations and food bases. can do. Furthermore, other additives such as other medicinal components, thickeners, plasticizers, colorants, fragrances, and the like can be contained in the immunostimulator. Note that WAK-1-A, which is an active ingredient of the immunostimulating agent of the present invention, has neither toxicity nor irritation to the skin and no side effects.

Next, although a reference example and an Example are given and this invention is demonstrated in more detail, this invention is not restrict | limited at all by these Examples. Of course, the percentage (%) is based on weight unless otherwise specified.
(Reference Example 1)
A medium prepared with seawater having a composition of 0.5% peptone, 0.1% yeast extract and 3% sucrose was sterilized in an autoclave at a temperature of 121 ° C for 20 minutes, and Pseudomonas sp. WAK-1 (Pseudomonas sp. WAK-1) From the slant culture for storage of the strain, inoculate one platinum loop into the above-mentioned sterilized medium (10 ml) in a test tube and perform shaking culture at a temperature of 25 ° C. for 24 hours. Inoculate 200 ml (121 ° C, 20 minutes) of sterilized medium prepared with seawater with 3% salt added to the above composition in a 500 ml Erlenmeyer flask and static culture at 25 ° C for 5 days. went. After culturing, the culture solution was filtered using a filter aid (Celite), and a 2-fold amount of ethanol was added to the supernatant from which the cells had been removed to obtain a white precipitate. This precipitate was collected and dissolved in 200 ml of water, and twice the amount of ethanol was added again to this solution to precipitate the polysaccharide, which was pulverized by freeze-drying. A fraction eluted with 0.4 M NaCl from a fraction adsorbed by DEAE-cellulose ion exchange column chromatography, which was dissolved in M / 100 phosphate buffer (pH = 7.0) and equilibrated in advance with the same buffer. Minutes were collected and lyophilized after dialysis to obtain acidic mucopolysaccharide powder.
The polysaccharide thus obtained is confirmed to be homogenous using a cellulose acetate membrane electrophoresis method and is a known polysaccharide WAK-1-A by chemical analysis and nuclear magnetic resonance analysis. confirmed.

(Reference Example 2)
The pre-culture was treated in the same manner as in Reference Example 1, and then this pre-cultured solution was inoculated into 200 ml of a sterile medium prepared from seawater having the above composition in a 500 ml Erlenmeyer flask (121 ° C., 20 minutes) and 25 ° C. The culture was gently shaken at the temperature of 5 days. After culturing, the cells were removed using a membrane filtration apparatus equipped with a hollow fiber MF membrane module (Spectrum) having a pore size of 0.2 μm, and a hollow fiber UF membrane module (Spectrum) having a molecular weight of 50,000 cut was removed from this solution. The polymer fraction obtained by a membrane filtration apparatus equipped with a product manufactured by Kogyo Co., Ltd. was concentrated, desalted and recovered in a short time, and pulverized by freeze-drying. This is dissolved in M / 100 phosphate buffer (pH = 7.0) and fraction eluted with 0.4M NaCl from the fraction adsorbed by DEAE-cellulose ion exchange column chromatography previously equilibrated with the same buffer. Were collected and freeze-dried after dialysis to obtain acidic mucopolysaccharide powder. The membrane filtration apparatus used was SYLS-SB04 type manufactured by Toyobo Engineering.
The polysaccharide thus obtained is confirmed to be homogenous using a cellulose acetate membrane electrophoresis method and is a known polysaccharide WAK-1-A by chemical analysis and nuclear magnetic resonance analysis. confirmed.

(Reference Example 3)
The pre-culture was treated in the same manner as in Reference Example 2, and 250 ml of agar medium containing 1.5% agar added to the medium containing sucrose described in Reference Example 2 was spread on a flat plate (18 × 26 cm), After smearing and culturing at a temperature of 25 ° C. for 7 days, scrape the sticky matter formed on the surface of the agar plate, suspend it in 1% phenol solution, and filter the cells by the same method as in Reference Example 1. The fraction obtained by adding ethanol to the supernatant obtained by the removal was collected, and the fraction precipitated by adding 5% quaternary ammonium salt (Cetavlon) solution after dissolution in water was collected by filtration. This was dissolved in 4M NaCl, and ethanol was added again to collect the precipitated fraction. The fraction was dissolved in water, dialyzed, and freeze-dried to obtain a polysaccharide. A fraction eluted with 0.4 M NaCl from a fraction adsorbed by DEAE-cellulose ion exchange column chromatography dissolved in M / 100 phosphate buffer (pH = 7.0) and equilibrated in advance with the same buffer. Were collected and freeze-dried after dialysis to obtain acidic mucopolysaccharide powder.
The polysaccharide thus obtained is confirmed to be homogenous using a cellulose acetate membrane electrophoresis method and is a known polysaccharide WAK-1-A by chemical analysis and nuclear magnetic resonance analysis. confirmed.

  Using WAK-1-A obtained in Reference Example 2, the macrophage activation and IL-12 production-inducing action of the mouse-derived macrophage-like cell line (J774.1) was examined, and compared with the case where no sample was added. Thus, NO and IL-12 production amounts in the sample addition system were determined. Macrophage activation was compared with activation by lipopolysaccharide (LPS, Sigma) used as a positive control, using nitrite ion concentration in the culture supernatant as an index.

(Measurement method of nitrite ion and IL-12 concentration)
As the culture solution, RPMI1640 medium (manufactured by Kojin Bio Inc.) containing 10% (V / V) FBS was used. 100 μl of the above culture solution containing the mouse-derived macrophage-like cell line J774.1 (Riken Cell Bank) at a predetermined concentration was seeded in a 96-well plate (1.5 × 10 ⁵ cells / well) to induce differentiation into macrophage cells. Then, a sample was added and cultured at 37 ° C. under 5% CO ₂ . The sample was dissolved in the culture medium so as to have a concentration of 10 mg / ml, and then sterilized with a 0.2 mm filter before use. After culturing for 24 hours, the culture supernatant was collected, and the nitrite ion concentration produced by oxidation of nitric oxide (NO) in the medium was determined by the Grease reagent method, and the IL-12 concentration was determined by the cytokine measurement kit (BioSource International, Inc.) and measured by the ELISA method. The IL-12 concentration was measured as IL-12p40 + p70. The NO production amount was determined by measuring the NO production amount when LPS (10 mg / ml) as a positive control was added, and the specific activity (NO production amount of the sample relative to the NO production amount of LPS, unit:%) was defined as the NO production ability. . These results are shown in FIGS. 1 and 2, respectively.

  As is clear from FIG. 1, no NO production induction was observed in the stimulation of macrophages in the control. However, WAK-1-A promoted NO production induction in a concentration-dependent manner and was found to have a macrophage activation effect.

  As is clear from FIG. 2, IL-12-inducing activity was not observed at all in the stimulation of macrophages in the control, but IL-12 production induction was promoted by stimulation with WAK-1-A. Since IL-12 has a function of suppressing differentiation into Th2 cells, WAK-1-A can be used to suppress the differentiation of Th2 cells and to fundamentally treat allergic reactions, and is more potent and A highly safe allergy prevention and treatment drug can be provided.

  The above-mentioned WAK-1 strain used in Reference Examples 1, 2, and 3 is the National Institute of Advanced Industrial Science and Technology, Patent Biological Deposit Center, 1-1-1 Higashi, Tsukuba, Ibaraki, Japan 305-8586 1 Deposited at No. 6 and deposited on August 28, 2002 under the deposit number FERM P-18888, and then transferred to the deposit under the Budapest Treaty and deposited under the deposit number FERM BP-8275. .

FIG. 1 shows macrophage activation. FIG. 2 shows the effect of promoting macrophage IL-12 production induction.

Claims (3)

A macrophage activator comprising an acidic mucopolysaccharide produced by marine bacteria or a physiologically acceptable salt thereof as an active ingredient ,
Has interleukin 12 production-inducing activity,
The acidic mucopolysaccharide is a compound represented by the following structural formula (I):

(In the above structural formula, GalNAcp is a pyranose-type N-acetylgalactosamine residue, GlcUAp is a pyranose-type glucuronic acid residue, D is a D-type, L is an L-type, Pyr is pyruvic acid, and n is a repeat. Represents the number of each.)
A macrophage activator characterized in that the compound represented by the structural formula (I) is contained at least 0.001% by weight based on the total weight of the macrophage activator.   The macrophage activator according to claim 1, wherein the compound represented by the structural formula (I) is contained in an amount of 0.01 to 20% by weight based on the total weight of the macrophage activator. An immunostimulant comprising an acidic mucopolysaccharide produced by marine bacteria or a physiologically acceptable salt thereof as an active ingredient,
Has interleukin 12 production-inducing activity,
The acidic mucopolysaccharide is a compound represented by the following structural formula:

(In the above structural formula, GalNAcp is a pyranose-type N-acetylgalactosamine residue, GlcUAp is a pyranose-type glucuronic acid residue, D is a D-type, L is an L-type, Pyr is pyruvic acid, and n is a repeat. Represents the number of each.)
An immunostimulant comprising the compound represented by the structural formula (I) at least 0.001% by weight based on the total weight of the immunostimulant.

Images