Search PubMed⌕ Search

Biomedical subjects

Y Kumazawa

Publications and source records attributed to Y Kumazawa.

At least 109 records · Page 6Linked to original sources

Effect of stereospecificity of chemically synthesized lipid A-subunit analogues GLA-27 and GLA-40 on the expression of immunopharmacological activities.

Tumor necrosis factor (TNF)-inducing, mitogenic, polyclonal B cell activation (PBA), macrophage activation and antiviral activities of chemically synthesized lipid A-subunit analogues, GLA-27 and GLA-40, were investigated. The structure of GLA-27 comprises 4-O-phosphono-D-glucosamine carrying tetradecanoyl and 3-tetradecanoyloxytetradecanoyl [C14-O-(C14)] groups as the 3-O- and 2-N-acyl substituents, respectively. GLA-40 is a 1-deoxy compound of GLA-27. The activities of stereoisomers, (R) and (S) forms at the C3 position of the C14-O-(C14) group, of both compounds were also investigated. TNF-inducing activity of the (S) isomers of GLA-27 and GLA-40 was stronger than that of the (R) isomers while the (R) isomers exhibited stronger mitogenic and PBA activities than the (S) isomers. With respect to macrophage activation such as phagocytosis, acid phosphatase and N-acetyl-beta-D-glucosaminidase activity as cellular lysosomal enzymes and cytostasis, peritoneal macrophages obtained from mice administered i.p. with test samples showed significant activities. Among stereoisomers of GLA-27, the (R) isomer exhibited somewhat stronger phagocytic and lysosomal enzyme activities than those of the (S) isomer while there was no appreciable difference in the activities between the isomers of GLA-40. Significant cytostasis-inducing activity was observed in stereoisomers tested. All of the isomers showed remarkable antiviral activity against vaccinia virus.

Animals↗

Functional maturation of immature B cells accumulated in the periphery by an intraperitoneal administration of a traditional Chinese medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to).

We found that an intraperitoneal (ip) injection of a traditional Chinese herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to), induced accumulation of B lymphocytes (sIgM+) in the peritoneal cavity and spleen. 1) Cell surface marker analysis by a fluorescence-activated cell sorter (FACS) demonstrated that the accumulated B cells on day 4 or 7 after shosaiko-to administration (early phase) were composed mainly of sIgM+IgD- cells and suggested that these B cells maturated into sIgM+IgD+ cells on days 10 or 14 (late phase). Relative decrease of IgM+IgD+ cells at early phase was more profound in peritoneal cells (PC) than in spleen cells. 2) With respect to spleen lymphocytes, antibody responses to a thymus-independent (TI) antigen of type 2 (trinitrophenylated Ficoll) and a thymus-dependent (TD) antigen (sheep erythrocyte) were enhanced at late phase but not at early phase. In contrast, responses to trinitrophenylated lipopolysaccharide (TNP-LPS) as a TI-1 antigen and LPS as a B cell mitogen or a polyclonal B cell activator were enhanced markedly at early phase but declined at late phase. 3) With respect to peritoneal lymphocytes, responses to LPS were suppressed at early phase but recovered at late phase. Enhanced responses to TI and TD antigen at late phase in spleen lymphocytes and suppressed response to LPS at early phase in peritoneal lymphocytes may be explained by increases of IgM+IgD+ mature B cells and IgM+IgD- immature B cells, respectively, at those times. Enhanced responses to TI-1 or LPS in spleen lymphocytes at early phase may be explained by elevated sensitivity of IgM+IgD+ cells which reside in the spleen before shosaiko-to administration and receive the direct stimulation by shosaiko-to, or by acquired responsiveness of IgM+IgD- cells which migrate after stimulation with shosaiko-to.

Animals↗

Protective effect of a traditional Chinese medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to), on Pseudomonas aeruginosa infection in mice.

Survival of mice after intraperitoneal (ip) or intravenous (iv) infection with Pseudomonas aeruginosa was augmented in the mice that had been pretreated ip with a Chinese traditional herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to) 6 hours or 4 days previously. 1) The pretreatment with shosaiko-to 6 hours previously induced an accumulation of polymorphonuclear leukocytes (PMN) in the peritoneal cavity, and its protective effect against ip infection was not impaired by treatment with carrageenan, a macrophage blocking agent. These results suggested that the protective effects of shosaiko-to against P. aeruginosa infection depended mainly on PMN in mice pretreated at this timing. 2) The pretreatment with shosaiko-to 4 days previously induced an accumulation of macrophages showing an augmented phagocytosis of P. aeruginosa in vitro in the presence of immune serum, and its protective effect against P. aeruginosa was impaired by treatment with carrageenan. In addition, the pretreatment with shosaiko-to accelerated the bacterial clearance from the blood. The sera obtained from mice treated with shosaiko-to 4 days previously showed a high titer of antibody specific to P. aeruginosa. When this sera was transferred to naive mice, these recipients showed an accelerated bacterial clearance and an increased survival to challenge infection with P. aeruginosa. These results suggested that protective effects of shosaiko-to against P. aeruginosa infection at this timing depended on cooperation of macrophages and antibody which produced by stimulation of shosaiko-to, a polyclonal B cell activator. Such polyclonal antibodies were also effective on protection against encapsulated Klebsiella pneumoneae to which antibody was essential in the expression of resistance. These results suggested that shosaiko-to could augment nonspecific resistance to a variety of bacteria to which antibody plays an effective role.

Animals↗

Structural requirements for inducing in vitro B lymphocyte activation by chemically synthesized derivatives related to the nonreducing D-glucosamine subunit of lipid A.

Mitogenic and polyclonal B cell activation (PBA) activities of 16 synthetic compounds related to the nonreducing D-glucosamine (GlcN-II) subunit of lipid A were investigated. Among compounds possessing the GlcN backbone, a 4-O-phosphorylated GlcN derivative carrying N-linked 3-tetradecanoyloxytetradecanoyl [C14-O-(C14)] and 3-O-linked tetradecanoyl (C14) groups, GLA-27, expressed the highest degree of both activities. Omission of the 3-O-linked C14 group from GLA-27 and transfer of the C14 group to the C-6 position induced critical changes in expression of activities. Both 4-O-phosphorylated compounds carrying an N-linked C14 or 3-hydroxytetradecanoyl (C14OH) group instead of the C14-O-(C14) group in GLA-27 showed no detectable activity. Substituting a 3-O-linked C14 group in GLA-27 for the C14-O-(C14) group also markedly decreased mitogenic and PBA activities. Change of phosphorylation site from the C-4 to the C-6 position and bisphosphorylation at the C-4 and C-6 positions induced somewhat weak depression. Much weaker activities were observed in a compound carrying N-linked 3-dodecanoyloxydodecanoyl [C12-O-(C12)] and 3-O-dodecanoyl (C12) as fatty acid substituents. No detectable activity was seen in a compound carrying N-linked 3-hexadecanoyloxyhexadecanoyl [C16-O-(C16)] and 3-O-hexadecanoyl (C16), indicating that the most suitable carbon chain length for expressing the activities is C14. Regarding structural change of the GlcN backbone, a 1-deoxy derivative of GLA-27 exhibited stronger activity than did GLA-27 itself. Mitogenic and PBA activity of GLA-27 were stronger than those of lipid X, which corresponds to the reducing D-GlcN (GlcN-I) subunit of Escherichia coli lipid A and is a 1-O-phosphorylated GlcN derivative carrying N- and 3-O-linked C14OH groups. These results indicate that N-linked acyloxyacyl and 3-O-linked acyl groups and phosphorylation are critical for expressing both mitogenic and PBA activities.

Animals↗

Structure-activity relationship of lipid A: comparison of biological activities of natural and synthetic lipid A's with different fatty acid compositions.

To investigate the structure-activity relationships, various biological activities, including pyrogenicity, lethal toxicity, elicitation of Shwartzman reaction, mitogenicity and tumor necrosis factor (TNF)-inducing activity, were compared among natural and synthetic lipid A's differing in fatty acid composition. In all these tests, natural lipid A's from Escherichia coli and Salmonella minnesota and synthetic LA-15-PP, which carries 3-hydroxy- and 3-acyloxy-tetradecanoyl groups at the 2, 3 and 2', 3' positions, respectively, showed the strongest activities among the tested lipid A's. In contrast, LA-16-PP, in which the amide-bound 3-hydroxytetradecanoic acid at position 2 of LA-15-PP is replaced by 3-hexadecanoyloxytetradecanoic acid, exhibited lower activity than LA-15-PP and natural lipid A's. Although LA-16-PP has been assumed to have a typical Salmonella lipid A structure (and, in fact, it has a structure corresponding to one of the components of Salmonella lipid A), the activity of this synthetic compound was not comparable to that of natural Salmonella lipid A. LA-17-PP, in which tetradecanoic acid is the sole fatty acid component, exhibited relatively strong mitogenicity and TNF-inducing activity, but very low pyrogenicity. The activities of LA-18-PP, which has ester-bound tetradecanoic acid and amide-bound 3-hydroxytetradecanoic acid, were lower than those of LA-17-PP. The results indicate that the differences in fatty acid composition of lipid A's have important influences on the biological activities studied.

Animals↗

Effects of backbone structures and stereospecificities of lipid A-subunit analogues on their biological activities.

Among chemically synthesized analogues corresponding to the nonreducing sugar part of lipid A, we have found an analogue (GLA-27) which exhibits Limulus, mitogenic, polyclonal B cell activation (PBA), interferon-inducing, and tumor necrosis factor (TNF)-inducing activities but not pyrogenic activity. The structure of GLA-27 comprises 4-O-phosphono-D-glucosamine with tetradecanoyl and 3-tetradecanoyloxytetradecanoyl (C14-O-(C14] groups as the 3-O- and 2-N-acyl substituents, respectively. Derivatives of GLA-27 with different backbone structures, such as the 1-deoxy, 3-epimeric, 3-amino, and 1-deoxy-3-epimeric derivatives of glucosamine, were chemically synthesized, and their mediator-inducing activities such as interferon- and TNF-inducing activities were investigated in comparison with their B cell activation activities including mitogenic and PBA activities. Among these derivatives, a derivative with a 1-deoxyglucosamine backbone (GLA-40) exhibited stronger B cell activation activities than those of GLA-27 while the mediator-inducing activities of GLA-40 were weaker than those of GLA-27. In addition to these derivatives, stereoisomers of GLA-27 which possess the (R) and (S) forms of C14-O-(C14) as the 2-N-acyl substituent were also synthesized and their biological activities compared. The (S) isomer exhibited much stronger mediator-inducing activities than the (R) isomer. On the other hand, B cell activation activities of the (R) isomer were strong and those of the (S) isomer weak. These results clearly demonstrate that mediator-inducing activities and B cell activation activities can be selectively expressed by modifying the structures of lipid A analogues.

Animals↗

Accumulation of immature B and null lymphocytes in the periphery after intraperitoneal administration of traditional Chinese medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to).

Accumulation of lymphocytes after an intraperitoneal (ip) injection of a traditional Chinese herb medicine, XIAO-CHAI-HU-TANG (Japanese name: shosaiko-to), was investigated. Shosaiko-to induced marked accumulation of lymphocytes rather than macrophages in the peritoneal cavity of ICR mice, whereas various kinds of irritants, e.g. proteose-pepton, Escherichia coli lipopolysaccharide (LPS), OK-432 and Corynebacterium parvum, induced preferential accumulation of macrophages rather than lymphocytes. By means of analysis using two-color fluorescence-activated cell sorter (FACS), it was revealed that the increased lymphocyte subpopulations not only in the peritoneal cavity but also in the spleen of C3H/He mice by the injection of shosaiko-to were comprised of both immature B (IgM+ and IgD-) and null (thyl- and Ig-) cells. This effect of shosaiko-to was observed in other C5 normal strains, C3H/HeJ (LPS-nonresponder), C57BL/6, BALB/c and athymic nu/nu (ICR background) mice, but not in C5 deficient strains, AKR/J, A/J and DBA/2 mice, indicating that the accumulation of immature B and null cells in the periphery induced by shosaiko-to is closely related to the complement system.

Animals↗

A new synthetic pathway to adenine-2-d, 9-alkyladenine-2-d, adenosine-2-d, and 2'-deoxyadenosine-2-d.

Unambiguous assignments of the purine ring protons in the NMR spectra of adenine (Ia) and its 9-substituted derivatives (Ib-f) have been made by comparison with those of the isotopically labeled adenines VIIIa-f. 9-Alkyl-2-deuterioadenines (VIIIb-d), adenosine-2-d (VIIIe), and 2'-deoxyadenosine-2-d (VIIIf) were synthesized from the 9-substituted adenines Ib-f through cyclization of the monocyclic intermediates VIb-f with formic acid-d2 or 1-(formyl-d)-2(1H)-pyridone. Hydrolysis of VIIIe with 0.5 N aq. HCl gave adenine-2-d (VIIIa) in 77% yield.

Adenine↗

B cell activation and adjuvant activities of chemically synthesized analogues of the nonreducing sugar moiety of lipid A.

Immunological activities of synthetic lipid A analogues (derivatives of 3-O-tetradecanoyl D-glucosamine) were investigated. Compounds possessing a N-tetradecanoyloxytetradecanoyl group with or without a 4-O-phosphoryl group exhibited both mitogenic and polyclonal B cell activating activities. Among these, the phosphorylated compound exhibited strong activity. 4-O-phosphorylated analogues with a N-tetradecanoyl group or 6-O-tetradecanoyl group in addition to N-3-hydroxyacyl groups showed no activity. All the analogues tested showed adjuvant activity, which was determined by augmentation of IgM antibody response against sheep erythrocytes. Relationship between chemical structure and biological activities is also discussed.

Adjuvants, Immunologic↗

Immunopotentiator separated from hot water extract of the seed of Benincasa cerifera Savi (Tohgashi).

The separation and properties of a new immuno-potentiator, Benincasa cerifera mitogen (BCM) fraction, were investigated. BCM fraction was separated from hot water extract of the seed of Benincasa cerifera Savi (Tohgashi) by gel filtration using Sepharose 4B. BCM fraction is a heteropolymer consisting of uronic acid, neutral sugars, protein, and phosphorus. The proliferation and differentiation of murine B cells were markedly stimulated by BCM fraction. The in vitro development of peritoneal macrophages into antitumor macrophages was also activated by the addition of BCM fraction to cultures. BCM fraction augmented the IgM and IgG antibody responses against sheep erythrocytes (SRBC) and the induction of delayed-type footpad reaction against SRBC. The antitumor activity of BCM fraction was observed in terms of prolongation of the survival period of mice bearing Meth A fibrosarcoma. After hydrolysis with 1% acetic acid at 100 degrees C for 4 h, marked mitogenic activity was found in a precipitate composed of 29% neutral sugars, 50% uronic acid, 1% protein, and 0.1% phosphorus. The precipitate did not contain detectable amino sugar. The possibility that the biological activities of BCM fraction may be due to contamination by bacterial lipopolysaccharide was ruled out on the basis of the results of chemical analysis and of marked mitogenicity noted in C3H/HeJ spleen cell cultures.

Acetates↗

Antigen-specific augmentation of murine immediate hypersensitivity-like footpad reaction by a T-cell factor in the culture supernatant of immune spleen cells.

An antigen-specific factor capable of augmenting delayed-type hypersensitivity (DH) in the culture supernatants from immune spleen cells and erythrocyte antigen has been found. These culture supernatants also augmented an immediate hypersensitivity-like reaction which appeared in advance of the classical DH reaction. In this paper, the basic characteristics and cells producing the augmentation factor (IAF) involved in immediate hypersensitivity-like reaction were investigated. Maximum activity of IAF was detected in a supernatant from 24-hr culture of immune spleen cells and antigen. In vitro antigen stimulation was essentially required for the production or release of IAF. IAF showed antigen-specificity. IAF was produced or released by T cells. In addition to these facts, the DH-augmentation factor proved to be a T-cell product.

Animals↗

Structural requirements of lipid A responsible for the functions: a study with chemically synthesized lipid A and its analogues.

To confirm the revised lipid A structure of Escherichia coli and to establish the structure responsible for its functions, biological activities of the synthetic compounds based on the presented structure of E. coli lipid A were investigated. Compound 506, 2-deoxy-6-O-(2-deoxy-2-[(R)-3-dodecanoyloxytetradecanoylamino]-3-O [(R)3-tetradecanoyloxytetradecanoyl]-beta-D-glucopyranosyl]-3-O-[(R) -3-hydroxytetradecanoyl]-2-[(R)-3-hydroxytetradecanoylamino]-alpha -D-glucopyranose 1,4'-bis(phosphate), exhibited activities identical to those of natural E. coli lipid A in eliciting Shwartzman reaction and tests on lethality, pyrogenicity, interferon- and tumor necrosis factor-inducing activities as well as in B-cell activating activity and Limulus amebocyte lysate gelating activity. With the exception of the Shwartzman reaction the monophosphorylated synthetic compounds at either the 1 or 4' position showed slightly lower activities than the compound with the bisphosphorylated compound (Compound 506). The compound without the phosphate group showed no or only very weak activities. The structural requirements for each activity (i.e. binding position and composition of fatty acids and presence of phosphate groups) are discussed taking into account the results of previous investigations.

Animals↗

Lymphocyte activation by a polysaccharide fraction separated from hot water extracts of Angelica acutiloba Kitagawa.

The action of a polysaccharide fraction obtained from hot water extracts of Angelica acutiloba Kitagawa, termed as Angelica immunostimulating polysaccharide (AIP) fraction, on murine lymphocytes participating in antibody responses was investigated. When AIP fraction was injected concomitantly into mice immunized with antigens, immunoglobulin M (IgM) and IgG antibody responses against sheep erythrocytes (SRBC) increased significantly, but IgM response against T-independent antigens such as trinitrophenylated lipopolysaccharide (TNP-LPS) and TNP-Ficoll did not augment. Murine B lymphocytes were polyclonally activated in vitro and in vivo by AIP fraction to differentiate into antibody-forming cells as functionally matured cells. The differentiation of B lymphocytes to an intermediate stage capable of responding to helper T lymphocytes was also stimulated by the administration of AIP fraction into CDF1 and C3H/HeJ mice. A concomitant injection of AIP fraction with SRBC for carrier priming resulted in the increment of anti-TNP IgM antibody response in cultured reconstituted with unprimed B and SRBC-primed T lymphocytes, indicating that AIP fraction can stimulate T lymphocytes.

Animals↗

Antigen-specific augmentation factor involved in murine delayed-type footpad reaction. I. Nature of augmentation factor.

A humoral factor capable of augmenting antigen-specific DTH has been found in the culture supernatant of immune spleen cells and erythrocyte antigen. In this study, a similar factor was identified in the sera of mice sensitized and elicited with heterologous erythrocytes, and the nature of this factor was investigated. Elicitation with antigen was essentially required for the production of the augmentation factor in sensitized mice. The factor showed antigen specificity and antigen-binding capacity. The activity was not assigned to immunoglobulins, as demonstrated by an absorption test with rabbit anti-mouse immunoglobulin-conjugated Sepharose. The activity was stable to heating at 56 degrees C for 30 min, to changes of pH from 3 to 10, and to treatment with trypsin or neuraminidase. The molecular weight of this factor was about 200,000 to 450,000.

Animals↗

Biological activities of analogues of lipid A based chemically on the revised structural model. Comparison of mediator-inducing, immunomodulating and endotoxic activities.

Lipid A analogues were chemically synthesized based on the model structure recently revised, and biological activities of the analogues were tested. The analogue, (beta-1,6)-linked glucosamine disaccharide carrying ester-bound 3-hydroxytetradecanoic acids at 3 and 3' position of reducing and nonreducing glucosamine in addition to amide-bound 3-hydroxytetradecanoic acids and glycosidic-linked and ester-linked phosphate groups, showed much stronger activities for mediator inducing and immunomodulating as well as endotoxic activities than those exhibited by the previously synthesized analogues based on the old model. Among the activities tested, induction of interferon and tumor necrosis factor as well as mitogenicity, adjuvanticity and pyrogenicity were, however, not expressed so strongly as natural lipid A used as controls. In contrast, the analogue exhibited comparable activities to those of control lipid A in the test of lethal toxicity to mice and gelating activity of Limulus amebocyte lysate. Other synthetic analogues carrying a phosphate group showed comparable, slightly stronger or weaker activities depending on the test, but nonphosphorylated analogue exhibited no apparent or only very weak activities.

Adjuvants, Immunologic↗

Mitogenic and polyclonal B cell activation activities of synthetic lipid A analogues.

The activation of murine B cells and macrophages by synthetic lipid A analogues, solubilized with triethylamine and complexed with bovine serum albumin, were investigated in vitro. The analogues used are nonphosphorylated, C-1 or C-4' monophosphorylated and C-1,4' diphosphorylated derivatives of beta-1,6-linked D-glucosamine disaccharide possessing both ester- and amide-bound fatty acid substituents. They were divided into 4 groups, A, B, C and D in terms of the fatty acid substitution. Ester- and amine-bound fatty acids of the analogues are both tetradecanoic acids (C14) in group A, C14 and (R)-3-hydroxytetradecanoic acids (C14-OH) in group B, both C14-OH in group C and C14-OH and (R)-3-tetradecanoyloxytetradecanoic acids in group D. Mitogenic activity was exhibited in spleen cells from C3H/HeN mice by the C-1 monophosphorylated analogues in groups A and B, and by the C-4' monophosphorylated analogues in groups B, C and D, but not in cells from C3H/HeJ mice. Nonphosphorylated analogues in groups A, B and C, and C-4' monophosphorylated analogue in group A showed negative mitogenic activity. Only the nonphosphorylated analogue in group D exhibited mitogenic activity in spleen cells from C3H/HeJ mice as well as those from C3H/HeN mice. None of the other analogues exhibited the activity in C3H/HeJ spleen cells. Polyclonal B cell activation activity was exhibited by the C-1 monophosphorylated analogues in groups A and B, and by the C-4' monophosphorylated analogues in groups C and D. Nonphosphorylated analogues in all groups and C-4' monophosphorylated analogues in groups A and B showed negative PBA activity. None of the analogues tested could induce any cytostatic macrophages from thioglycollate-elicited peritoneal macrophages.

Animals↗

Antigen-specific augmentation of delayed-type hypersensitivity by a humoral factor in the culture supernatant of immune spleen cells.

Supernatants were harvested from a 24-hr culture of immune mouse spleen cells and erythrocyte antigens. Delayed footpad reactions to such heterologous erythrocytes were augmented antigen specifically when the supernatants were transferred a few hours before immunization of recipients. The augmentation factor(s) contained in the supernatants may exert its effect on the induction phase of delayed-type hypersensitivity.

Animals↗

Activation of peritoneal macrophages by berberine-type alkaloids in terms of induction of cytostatic activity.

The antitumour alkaloids, berberine and coralyne were investigated in terms of their ability to induce chemiluminescent responses and cytostatic activity in macrophages against tumour cells in vitro. Berberine hydrochloride and sulfate, and coralyne chloride, which had no direct tumoristatic activities at a concentration of less than 0.15 micrograms/ml, activated macrophages to inhibit the incorporation of tritiated thymidine into EL4 leukemic cells. The activation of cytostatic macrophages by berberine was not augmented by the addition of a suboptimal dose of macrophage activating factor (MAF). Furthermore, a marked chemiluminescent response of macrophages was induced by treatment with berberine as well as with MAF or lipopolysaccharide. These results show that berberine and coralyne are potent macrophage activators for inducing cytostatic activity against tumour cells in vitro.

Animals↗