JPH05229953A - New anti-malignant tumor agent and immunopotentiator - Google Patents

Abstract

PURPOSE:To obtain a new anti-malignant tumor agent and an immunopotentiator from a cultured supernatant of Streptoverticillium hachijoense. CONSTITUTION:The objective new anti-malignant tumor or immunopotentiator contains substances having the following physicochemical properties as active ingredients. (a) Appearance, white to pale yellow powder; (b) solubility, readily soluble in water, sparingly soluble in acetic acid, etc., and insoluble in methanol, etc., (c) specific rotation, [alpha] =+0.0 to +2.39; (d) color reaction, positive to ninhydrin reaction, carbazole sulfuric acid method, phenol sulfuric acid method and Coomassie Brilliant Blue dye method; (e) elementary analysis, C 0.3-0.8%, H 0.7-1.6%, N 0.01-0.5%, O 3.5-7.5%, S 240-560ppm, Na 12.0-35.0%, PO4 56.5-84.6%; (f) molecular weight, about 660-300; (g) ultraviolet absorption spectrum, lambda max (epsilon)=254-259nm; (h) molecular weight excluding ash, about 660-300; (i) sugar content, 1.5-2.4mug/mg; (j) protein content, 0.9-2.0mug/mg.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel antineoplastic agent and immunostimulant.

[0002]

2. Description of the Related Art It has been conventionally known that various antitumor antibiotics are produced by microorganisms. Some of them have been put to practical use as anticancer agents. In particular, mitomycin C, bleomycin, adriamycin, neocarzinostatin and the like are known as anticancer agents derived from actinomycetes and are applied to therapy. However, many anti-tumor antibiotics cause myelosuppression, gastrointestinal disorders,
With side effects such as cardiac dysfunction and hair loss, it is a great burden for cancer patients. Further, in many cancer patients, the immunocompetence is lowered, the progression of cancer is promoted, the resistance to various bacteria is diminished, and serious infections are likely to occur. Against this background, the concept of quality of life has recently been considered as a treatment method for cancer from the clinical side, and in the field of anti-cancer agents as well, there are fewer side effects and the immunopotency of cancer patients has been improved. Increasingly trying to treat cancer is becoming more popular.

Streptoverticillium hachijo which is one of the actinomycetes
As an active ingredient derived from ense), the existence of a polyene antibiotic, tricomycin, which is effective for vaginal trichomoniasis, is known. In addition, one of the present inventors, Soeda, is Streptoverticillium hachijowens H-2609 strain (IFO 1278).
2) obtained an antitumor substance with a molecular weight of 1200 (Japanese Patent Publication No. 49-
42560, Defense Hygiene Vol. 14, No. 1, Page 1, 196
7). In addition, Kono reported an antitumor agent composed mainly of a protein having a molecular weight of 20,000 to 60,000, using the same bacterium (Japanese Patent Laid-Open No. Hei 10 (1999) -242242).
2-53729).

In the field of cancer chemotherapy, various antitumor agents are required in response to various cancer types and symptoms.

[0005]

DISCLOSURE OF THE INVENTION The object of the present invention is to provide a novel antitumor agent and immunostimulant.

[0006]

SUMMARY OF THE INVENTION The present invention provides a streptoba
-Obtained from culture supernatant of T.
It exhibits antitumor activity, and has the following physicochemical properties a) Appearance: White to pale yellow powder b) Solubility: Soluble in water, sparingly soluble in acetic acid, pyridine,
Tanol, ethanol, chloroform, dichlorometa
Insoluble in acetone d) Color reaction: ninhydrin reaction, carbazole sulfate
Method, phenol-sulfuric acid method and Coomassie Brilliant Bull-
Positive in dye method e) Elemental analysis value: C 0.3 to 0.8% H 0.7 to 1.6% N 0.01 to 0.5% O 3.5 to 7.5% S 240 to 560ppm Na 12.0 to 35.0% PO_Four 56.5 to 84.6% f) Molecular weight: 660 k to 300 g) Ultraviolet absorption spectrum: λmax (ε) = 254 to 259 nm (water
Solution) h) Molecular weight without ash: about 660k to 1200 i) Sugar content: 1.5 to 2.4 μg / mg (phenol sulfate
Method, glucose conversion) j) Protein content: 0.9-2.0 μg / mg (Coomasie brilliant
Antoble-dye method, bovine serum albumin equivalent)
Obtained by activating dialysate and desalting this substance
A new antineoplastic agent and immunostimulant containing a substance as an active ingredient
Concerned.

The active ingredient of the present invention can be obtained from the culture supernatant of Streptoverticillium hachijowens. The mycological properties of Streptoverticillium hachijowens are described in "A new antibiotic with anti-trichomonas and anti-cancer action, trichomycin" (Hosoya et al., Journal of Antibiotics, Vol. 10, 564).
Pp. 1952), the strain H-2609 of Streptoverticillium hachijowens is described,
Also, "Studies on the Antibiotics Substance Producing Strains H20
75, H-2609 and H-3030 "(The Journal of Antibiotics Series A, Volume 7, Volume 1
No., p. 10, 1954), the H-2609 and H-2075 strains of Streptoverticillium hachijowens are described. The H-2609 strain is IFO 12782.
Has been deposited as an issue. In the present invention, H-2609
Strains, H-2075 strains, H-3030 strains can be used as specific strains, but not limited to them, the organic substance component which belongs to Streptoverticillium hachijowens and is an active substance in the above-mentioned active ingredient is used. As long as you have the ability to produce
Other wild strains or mutant strains obtained by mutagenizing these wild strains by a conventional method (for example, ultraviolet irradiation, mutagen treatment, genetic engineering treatment) can also be used.

Cultivation of this actinomycete Streptoverticillium hachijowens can be carried out by the method described below, and the conditions shown there, especially as shown in the examples of the present invention, If the conditions are not observed, the medicinal effects may vary and satisfactory results may not be obtained.
As the nutrient source, known ones conventionally used for culturing actinomycetes can be used. For example, glucose, molasses, starch, dextrin, sucrose, starch syrup, animal and vegetable oils and the like can be used as the carbon source. As a nitrogen source, soybean flour, wheat germ, corn steep liquor, meat extract, peptone,
Yeast extract, ammonium sulfate, sodium nitrate, urea and the like can be used. In addition, if necessary, it is effective to add inorganic salts capable of producing sodium, potassium, calcium, magnesium, cobalt, chlorine, phosphoric acid, sulfuric acid and other ions. In addition, organic and inorganic substances that help the growth of bacteria and promote the production of active ingredients can be added appropriately.

As a culture method, a culture method under aerobic conditions is suitable, and a suitable temperature for the culture is 27 to 30 ° C., but in many cases, the culture is carried out at around 28 ° C. Also, a suitable pH for culture
The range is 7.0-9.0. By culturing under the above conditions for 3 to 7 days, a highly active culture solution can be obtained.

The isolation of the active ingredient from the culture broth is roughly carried out according to the method for purifying the exotoxin produced by the pathogenic fungus of Hosoya et al. (Experimental Medicine, Vol. 28, page 429, 1944), for example, as follows. It can be carried out by the method as shown, but also if the conditions as shown there, especially the conditions as shown in the examples, are not obtained, a component having the predetermined composition and physical properties cannot be obtained, or the drug efficacy varies. May occur and a satisfactory result may not be obtained. In this separation and purification, bacterial cells were removed from the culture solution, and the supernatant was treated with 50% (w / v) aqueous solution of electrolyte inorganic salt such as zinc chloride and ammonium sulfate to a final concentration of about 2.5%.
The resulting precipitate is collected, and 10% (w / v) of an aqueous solution of sodium phosphate such as dibasic sodium phosphate is added to the supernatant to about 55% (w / v). In addition, extraction is performed, and a lower organic solvent such as methanol, ethanol, propanol, butanol, etc., which is a hydrophilic organic solvent, or a ketone solvent such as acetone, isobutyl ketone, etc., is added to the extract, and the precipitated fraction is collected. . The collected precipitate is dissolved in distilled water, and then sterilized by filtration using an appropriate filtration membrane,
By freeze-drying the filtrate, the antitumor active ingredient is obtained.

The active ingredient according to claim 1 can be obtained by the above method, and comprises an inorganic salt as a major component and an organic substance as a minor component. The inorganic salt is essentially dibasic sodium phosphate, which stabilizes the organic matter and also acts as a buffer, a dissolution-stabilizing action of the organic matter,
It has the action of dissolving toxins, etc., and is presumed to enhance the action as a new antineoplastic agent and immunostimulant in combination with organic substances.

[0012] And, the substance to be the active ingredient according to claim 1.
The quality has the following physical properties and I
R and UV are shown. (1) Appearance: White to pale yellow powder (2) Solubility: Easily soluble in water. Insoluble in acetic acid and pyridine. Me
Tanol, ethanol, chloroform, dichlorometa
Insoluble in acetone (4) Color reaction: Ninhydrin reaction, carbazole sulfate
Method, phenol-sulfuric acid method and Coomassie Brilliant Bull-
Positive by dye method (5) Elemental analysis: Carbon, hydrogen, by thermal conductivity detection method
The nitrogen contents are C: 0.3-0.8% and H: 0.7, respectively.
~ 1.6%, N: 0.01-0.5%, using a differential refractometer or heat
Oxygen content by the conductivity detection method is O: 3.5-7.5%,
Sulfur content by cylinder combustion-ion chromatography
Is S: 240-560ppm, sodium content is atomic absorption method
More sodium ion, 12.0-35.0%, containing phosphoric acid
Existence 56.5 to 84.6%. Water by Karl Fischer method
As a result, the value was 4.4 to 6.7%. (6) Molecular weight distribution: The molecular weight distribution measured by gel filtration is about
It was 600k to 300. (7) Ultraviolet absorption spectrum: spectrum measured in aqueous solution
Tor has a maximum absorption at 254 to 259 nm as shown in FIG.
One. (8) Red external absorption spectrum: measured with potassium bromide tablets
The spectrum is shown in Figure 2. (9) Melting point: Shrinks at 220 ℃ and gradually increases from around 230 ℃
And shows no clear melting point. (10) Molecular weight without ash: Approx. 660k to 1200 (11) Sugar content: 1.5 to 2.4 μg / mg (phenol sulfate
Method, glucose equivalent) (12) Protein content: 0.9-2.0 μg / mg (Coomasie brilliant
(Antoble-Dye method, bovine serum albumin conversion)

From the above results, it is presumed that the active ingredient of claim 1 is composed of an ash mainly containing dibasic sodium phosphate and an organic matter composed of a complex or mixture of proteins, sugars and the like.

The active ingredient according to claim 2 is a substance obtained by dialysis and desalting the substance to be the above-mentioned active ingredient, and is a substance in which inorganic salts are reduced. Where the inorganic salt is 0
However, there is no problem even if some remain. This is because this inorganic salt does not exhibit side effects as described above, but enhances the effect as a drug.
Incidentally, during the dialysis, some organic matter having a molecular weight close to that of the dibasic phosphate may be removed.

The active ingredient according to claim 3 is as defined in claim 1.
The substance was desalted by dialysis to a certain degree.
In addition to having the following physical properties, UV as shown
(Figure 3), IR (Figure 4), molecular weight distribution (Figures 5 and 6) Isoelectricity
Point electrophoresis (FIGS. 7 and 8) is shown. This material is
Since it is obtained by desalting,
The substance is more concentrated than the substance according to claim 1. Because
Thus, even if the dose is small, the same drug effect is exhibited. (1) outside
Appearance: White to pale yellow powder (2) Solubility: Easily soluble in water, sparingly soluble in acetic acid and pyridine,
Tanol, ethanol, chloroform, dichlorometa
Insoluble in acetone (4) Color reaction: Ninhydrin reaction, carbazole sulfate
Method, phenol-sulfuric acid method and Coomassie Brilliant Bull-
Positive by dye method (5) Elemental analysis: Carbon, hydrogen, by thermal conductivity detection method
The nitrogen contents are C: 39.3-39.6% and H: 6.0, respectively.
~ 6.1%, N: 10.1 ~ 10.4%, O: 31.5 ~ 32.5%, Bon
Sulfur content by combustion-ion chromatography is
S: 5500-6400ppm, sodium content by atomic absorption method
2.3-2.7% as sodium ion, phosphoric acid is phosphoric acid
The ion content was 3.0 to 3.1%. (6) Molecular weight distribution: The molecular weight distribution measured by gel filtration is about
It was 600k to 300. (7) Ultraviolet absorption spectrum: λmax (ε) = 257 to 258 nm (water
Solution). Figure 3 (8) Red external absorption spectrum: measured with potassium bromide tablets
The spectrum is shown in FIG. (9) Molecular weight without ash: Approx. 660k to 1200 (10) Sugar content: 76 to 104 μg / mg (phenol sulfate
Method, glucose equivalent) (11) Protein content: 71-101 μg / mg (Coomasie brilliant
(Antoble-Dye method, bovine serum albumin conversion)
The quality is not unevenly distributed in a specific pH range (Fig.
Conclusion from the migration data).

The conditions for gel filtration chromatography (protein molecular weight distribution) shown in FIG. 5 are as follows: column: G5,000 PW +
G3,000SW x L, flow rate: 1 ml / min, buffer: 20 mM phosphate buffer (pH 7.0) + 0.15 M NaCl, and the conditions for gel filtration chromatography (sugar molecular weight distribution) in Fig. 6 were the same. there were.

The substance according to claim 4 is obtained by further dialysis of the substance according to claim 3 to completely remove inorganic salts,
The organic matter is completely concentrated. Therefore, the dose may be smaller, but storage stability may be required.

Immunotherapy for cancer is a method of curing cancer by increasing the resistance of the tumor-bearing host to cancer, and in particular, activation of immunocompetent cells is at the core. Since this active ingredient activates macrophages and spleen cells, which are immunocompetent cells, and damages tumor cells, it can be greatly expected as an immunotherapeutic agent for cancer. Unlike chemotherapeutic agents, immunotherapeutic agents are unlikely to show side effects or toxicity such as blood disorders, digestive organ disorders, lung disorders, cardiotoxicity, nervous system disorders, skin disorders, secondary carcinogenesis, etc. It has the advantage that it can be used with peace of mind without causing other hematopoietic disorders or hepatorenal dysfunction.

Regarding the application of the present active ingredient to therapy, it is preferable to use it as an injection based on the results of animal experiments. Particularly, subcutaneous injection stimulates the reticuloendothelial system in vivo to enhance the immune system. Good to do. Also, it can be used in the form of oral preparations, suppositories, etc. by selecting the formulation method. The injection may be subcutaneous, intramuscular, or intravenous injection, and a dosage form such as a suspension, a solution, or a powder that is dissolved at the time of use is used. Moreover, it is not necessary to include a local anesthetic in the injection.

The dose of the active ingredient of the present invention is appropriately selected according to the symptoms of the patient, but it is generally 1 to 100 in adults.
It is preferable to administer mg / kg in divided doses 1 to several times a day, and the administration method is preferably oral or subcutaneous, intramuscular, intravenous or by injection into the affected area.

[0021]

EXAMPLES Next, the present invention will be specifically described by way of examples. Example 1 1) Production of substance according to claim 1 As production medium, glucose 0.5%, potato starch 2.
0%, polypeptone 0.5%, proteose peptone 1.
A medium having a composition of 0%, meat extract 0.3% and sodium chloride 0.75% (% is w / v) was used. The pH before sterilization is pH 7.2
It was adjusted to and used. The prepared medium was dispensed into 60 500-mL Sakaguchi flasks in 100 ml aliquots and then sterilized using a high-pressure steam sterilizer at 120 ° C for 20 minutes. Streptoverticillium hachijoense H26 subcultured on an agar medium for preserving actinomycetes in this medium
The 09 strain was inoculated by scraping with a platinum loop and shake-cultured at 28 ° C. for 3 days to give preculture. 10 ml of the precultured bacterial solution was inoculated into the same medium and shake-cultured at 28 ° C. for 5 days to carry out main culture.

After completion of the culture, about 6 L of the culture solution is sterilized, and then 1/20 volume of 50% (w / v) zinc chloride solution is added to the culture supernatant solution, and the mixture is centrifuged at 3000 rpm for 5 minutes to obtain. 10% (w / v) dibasic sodium phosphate solution was added to the precipitate so as to be 55% (w / v) of the culture supernatant volume, and the suspension was completely suspended for 1 hour at room temperature at 4 ° C.
After leaving still for several hours to overnight, the supernatant was obtained by decantation. Add 4 volumes of cold methanol to the supernatant and immediately centrifuge at 3000 rpm for 5 minutes. Pure water was added to the obtained precipitate, dissolved by heating, filtered through a glass fiber filter, and freeze-dried to obtain the desired product. The target product thus obtained has a total content of protein and sugar of 1.9 μg /
mg, and elemental analysis values are C: 0.5%, H: 1.2%, N:
0.1%, O: 6.0%, Na +: 31.0%, PO 4 -: 66.6
%, S: It has a molecular weight of 300 to 660 k. The yield at this time was about 60 g.

2) In vivo antitumor activity SPF · ddy mice (male, 4 weeks old) were treated with Ehrlich and Sarcoma 180 ascites tumor cells at 5 × 10 5 per mouse.
^Three were inoculated intraperitoneally. Within a few hours after cell transplantation, an antitumor component (the target substance obtained in 1) above was intraperitoneally administered,
Observation was performed for 45 days, and the survival rate of the mouse at that time was calculated. Table 1
Shows the antitumor effect against Ehrlich ascites tumor, and Table 2 shows the effect against Sarcoma 180 ascites tumor.

[0024]

[Table 1]

[0025]

[Table 2]

3) In vitro antitumor activity Macrophages and tumor cell lines collected from the peritoneal cavity of mice
BALB / 3T12-3 was mixed at a ratio of 4: 1 and cultured for 3 days in the coexistence of the antitumor active ingredient (the target substance obtained in 1) above, and the macrophage activating effect was examined by Giemsa staining. On the other hand, spleen cell activation was performed by removing the spleen of Balb / c mice and mechanically converting them into single cells, and then adding 37
Inoculate in a carbon dioxide incubator for 24 hours at ℃.
Then, the fluorescently labeled tumor cells YAC-1 were added to the splenocytes.
Was added, and after culturing for 4 hours, the number of residual tumor cells was measured by the fluorescence method. The results are shown in Table 3.

[0027]

[Table 3] In vitro, the antitumor active ingredient has the effect of activating mouse peritoneal macrophages and splenocytes to damage tumor cells, and an indirect antitumor activity was observed.

Example 2 1) Preparation of substance of claim 1 1) of example 1 was repeated separately to obtain the substance of claim 1 (lots 2, 3, 4). The elemental analysis values of these lots are shown in Table 4.

[0029]

[Table 4](Analysis method) C, H, N, O By thermal conductivity detection method By Na atomic absorption method Water content Karl Fischer method

Example 3 1) Production of substance of claim 3 60 g of the sample obtained in Example 1 was concentrated by the following method.
Polycondensation was performed to obtain the sample of claim 3. Smell of Example 1
Limit 3L of sample after filtration with glass fiber filter
Use an outer filtration membrane (pore size: molecular weight 3000) to concentrate 10 times.
Crushed, desalted and then freeze dried. Freeze-dry the freeze-dried product
Dissolve in 1/10 volume of water before drying and use cellophane tube
Dialysis for 5 hours and then lyophilize again
I got a thing. The target product thus obtained is composed of proteins and sugars.
The total content is about 200 μg / mg, and the elemental analysis value is   , And the molecular weight was 1200 to 660 k. Also at this time
The yield was 600 mg.

2) In Vivo Antitumor Activity SPF · ddy mice (male, 4 weeks old) were inoculated intraperitoneally with 5 × 10 ³ Ehrlich ascites tumor cells per mouse. Within a few hours after cell transplantation, the antitumor component (the target substance obtained in 1) above was intraperitoneally administered and observed for 45 days, and the mouse survival rate at that time was calculated. The results are shown in Table 5.

[0032]

[Table 5]

3) In vitro antitumor activity In addition to using the target substance obtained in 1) above, 3) of Example 1
It was operated in the same manner as. The results are shown in Table 6.

[0034]

[Table 6] In vitro, the antitumor active ingredient had the effect of activating mouse peritoneal macrophages and splenocytes to damage tumor cells, and thus showed indirect tumor activity.

[0035]

INDUSTRIAL APPLICABILITY The novel antitumor component of the present invention activates mouse peritoneal macrophages and spleen cells in vitro and indirectly has an antitumor effect, and in vivo also induces Ehrlich ascites tumors and Sarcoma 180 ascites tumors in mice. On the other hand, it shows antitumor activity and is expected to be useful as a novel anticancer agent.

[Brief description of drawings]

1 shows an ultraviolet absorption spectrum of an active ingredient of Example 1 in an aqueous solution.

FIG. 2 shows an infrared absorption spectrum of the active ingredient of Example 1 in a potassium bromide tablet.

FIG. 3 shows an ultraviolet absorption spectrum of the active ingredient of Example 3 in an aqueous solution.

FIG. 4 shows the infrared absorption spectrum of the active ingredient of Example 3 in a potassium bromide tablet.

FIG. 5 shows a protein molecular weight distribution of the active ingredient of Example 3 by gel filtration chromatography.

FIG. 6 shows the molecular weight distribution of sugars by gel filtration chromatography of the active ingredient of Example 3.

FIG. 7 shows the isoelectric point distribution of a protein obtained by liquid isoelectric focusing of the active ingredient of Example 3.

FIG. 8 shows the isoelectric point distribution of sugar of the active ingredient of Example 3 measured by liquid isoelectric focusing.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI technical display location (C12P 1/06 C12R 1:01) (72) Inventor Hiroshi Kawashima 1 Sakaigawa, Tobata-ku, Kitakyushu, Fukuoka -7-4-202 (72) Inventor Hiroyuki Oyama 5-17-29 Nakai, Kokurakita-ku, Kitakyushu, Fukuoka

Claims (5)

[Claims] 1. Streptoverticillium vulgaris
It was obtained from the culture supernatant of Ens and showed antitumor activity.
New Anti-Aggression Containing Substances with Physicochemical Properties as Active Ingredients
Tumor drug. a) Appearance: White to pale yellow powder b) Solubility: Easily soluble in water, sparingly soluble in acetic acid and pyridine,
Tanol, ethanol, chloroform, dichlorometa
Insoluble in acetone d) Color reaction: ninhydrin reaction, carbazole sulfate
Method, phenol-sulfuric acid method and Coomassie Brilliant Bull-
Positive in dyeing method e) Elemental analysis value: C 0.3 to 0.8% H 0.7 to 1.6% N 0.01 to 0.5% O 3.5 to 7.5% S 240 to 560ppm Na 12.0 to 35.0% PO_Four 56.5 to 84.6% f) Molecular weight: 660 k to 300 g) Ultraviolet absorption spectrum: λmax (ε) = 254 to 259 nm (water
Solution) h) Molecular weight without ash: about 660k to 1200 i) Sugar content: 1.5 to 2.4 μg / mg (phenol sulfate
Method, glucose conversion) j) Protein content: 0.9-2.0 μg / mg (Coomasie brilliant
(Antoble-Dye method, bovine serum albumin conversion) 2. A new anti-malignant tumor agent comprising the substance obtained by dialysis of the substance according to claim 1 and desalting as an active ingredient. 3. Streptoverticillium vulgaris
It was obtained from the culture supernatant of Ens and showed antitumor activity.
New Anti-Aggression Containing Substances with Physicochemical Properties as Active Ingredients
Tumor drug. a) Appearance: White to pale yellow powder b) Solubility: Easily soluble in water, sparingly soluble in acetic acid and pyridine,
Tanol, ethanol, chloroform, dichlorometa
Insoluble in acetone d) Color reaction: ninhydrin reaction, carbazole sulfate
Method, phenol-sulfuric acid method and Coomassie Brilliant Bull-
Positive in dye method e) Elemental analysis value: C 39.3 to 39.6% H 6.0 to 6.1% N 10.1 to 10.4% O 31.5 to 32.5% S 5500 to 6400ppm Na 2.3 to 2.7% PO_Four 3.0 to 3.1% f) Molecular weight: about 660k to 300g) Ultraviolet absorption spectrum: λmax (ε) = 257 to 258nm (water
Solution) h) Molecular weight without ash: about 660 k to 1200 i) Sugar content: 76 to 104 μg / mg (phenol-sulfuric acid method,
Glucose equivalent) j) Protein content: 71-101 μg / mg (Coomasie brilliant
(Tombre-dye method, bovine serum albumin conversion) 4. A new anti-malignant tumor agent comprising a substance obtained by dialysis of the substance according to claim 3 and desalting until the inorganic salt of PO ₄ is substantially eliminated, as an active ingredient. 5. An immunostimulant comprising the substance according to claim 1, claim 2, claim 3 or claim 4 as an active ingredient.