Demonstration of Akabane virus antigen using immunohistochemistry in naturally infected newborn calves

Eight newborn calves showing ataxia were necropsied and examined histologically. Six of seven cerebrospinal fluid samples collected from these animals had neutralizing antibody for Akabane virus (AKV). All examined calves had nonsuppurative encephalomyelitis, localized mainly in the midbrain and spinal cord. Corresponding to the encephalitic lesion, AKV antigen was demonstrated in neuroglial cells in the brain stem and neuronal cells in the ventral horn of the spinal cord. This is the first study to demonstrate AKV antigen by immunohistochemistry in naturally infected newborn calves.

Effects of astragali radix extract on carcinogenesis, cytokine production, and cytotoxicity in mice treated with a carcinogen, N-butyl-N'-butanolnitrosoamine

We studied the effects of astragali radix extract, a Chinese herb and one of eight components in Shikaron, on carcinogenesis, natural killer (NK) cell activity, and the cytokine production of lymphocytes in mice treated with a carcinogen, N-butyl-N'-butanolnitrosoamine (BBN). We found a significantly lower incidence of urinary bladder carcinoma in mice treated with BBN plus 10 mg/kg/day or more of Astragalus extract (7, 2, and 3 mice among 15 mice in 10, 20, and 40 mg/kg/day group, respectively, vs. 14 of 15 mice treated with BBN alone). Astragalus extract prevented the cytotoxic activity of lymphocytes against YAC-1 cells from the depression by BBN. It also protected the production of interleukin-2 and gamma-interferon of lymphocytes from the depression by BBN. These results, including our previous findings, suggest that the Astragalus extract exerts an anticarcinogenic effect in carcinogen-treated mice through activation of cytotoxic activity and the production of cytokines.

Characteristic cytokine products of Th1 and Th2 cells in hemodialysis patients

Dysfunction of the host defense against infection in hemodialysis (HD) patients has major clinical and socioeconomic implications. T helper type 1 (Th1) and type 2 (Th2) cytokines are implicated in regulating the immune responses and, therefore, may be involved in impaired status. The present study was designed to examine Th1 and Th2 cytokine profiles in 22 stable HD patients (aged 63 +/- 11 years) and 22 healthy controls (aged 60 +/- 6 years). The T cell activity was significantly retarded in HD patients as compared with normal persons. The proportions of T cytotoxic/suppressor cells and natural killer cells were significantly higher in HD patients than in controls. In contrast, the proportions of T helper/inducer and B cells were significantly lower in HD patients than in controls. The production of interleukin (IL) 2, which is involved in cell-mediated immune responses, and the production of IL-4 and IL-10, which affect humoral immunity, were significantly lower in patients than in controls. The production of IL-12 by macrophages and of interferon gamma by Th1 cells was significantly higher in HD patients than in controls. The concentration of plasma sIL-2R was significantly higher in patients than in controls. These results suggest that both cellular immunity induced by Th1 and humoral immunity induced by Th2 decrease in HD patients, but that improved IL-12 secretion by macrophages activated natural killer cells to produce interferon gamma, which in turn induced macrophage activity.

Anticarcinogenic effects of shikaron, a preparation of eight Chinese herbs in mice treated with a carcinogen, N-butyl-N'-butanolnitrosoamine

We studied the effects of Shikaron, which is composed of 8 Chinese herb extracts, on carcinogenesis and the cytotoxic activity and cytokine production of lymphocytes in mice treated with a carcinogen, N-butyl-N'-butanolnitrosoamine (BBN). We found a significantly lower incidence of urinary bladder carcinoma in mice treated with BBN plus Shikaron 200 mg/kg/day (5 of 20 mice, 25%), than in mice treated with BBN alone (16 of 20 mice, 80%). Shikaron protected the cytotoxic activity of lymphocytes against YAC-1 cells from suppression by BBN. Cytotoxic activity against P-815 cells significantly increased in mice treated with BBN plus Shikaron, as compared with normal mice and BBN-treated mice. Shikaron also protected production of interleukin-2 and interferon-gamma by lymphocytes from suppression by BBN. These findings strongly suggest that Shikaron exerted an anticarcinogenic effect in carcinogen-treated mice through activation of NK and LAK cells and cytokine production by T lymphocytes.

Immunological characteristics of the effector cells induced by a combination therapy with cyclophosphamide and allogeneic lymphocytes

A significant inhibition of tumor growth was observed when sarcoma 180 (S180)-bearing ICR strain mice were treated by a combination therapy, with a low dose of cyclophosphamide (CY) and an inoculation of allogeneic lymphocytes collected from C57BL/6 mice. The growth-inhibitory effect was significantly increased by an inoculation of a relatively lower dose of allogeneic lymphocytes (1 x 10(5) cells) and CY. The effector cells induced in the mice treated with CY and allogeneic lymphocytes expressed the Lyt 1.2, Lyt 2.2, IL-2R antigens on their membrane surface and did not express the H2KbDb (donor H-2) antigen, and they showed a specific cytostatic activity against S180 cells. These results strongly suggested that a combination therapy with a low dose of CY with an inoculation of allogeneic lymphocytes augmented an induction of specific cytotoxic T lymphocytes in the tumor-bearing recipient mice.

Release of superoxide anion from polymorphonuclear leukocytes stimulated by rubella viral antigen-antibody complex in vitro

Using a highly sensitive and specific chemiluminescence (CL) method, we detected the release of superoxide anion (O2-.) from human polymorphonuclear leukocytes (PMNLs) stimulated by rubella viral antigen-antibody complex (VAAC) adsorbed on latex particles. The amount of superoxide anion produced by PMNLs was proportional to the amount of VAAC. Neither rubella virus alone nor antibody alone, adsorbed on latex particles, stimulated production of superoxide anion by PMNLs. It is likely that rubella virus requires the presence of antibody in order to be recognized by PMNLs, and that the superoxide anion is somehow involved in the disease process of rubella.

Effects of Lentinus edodes, Grifola frondosa and Pleurotus ostreatus administration on cancer outbreak, and activities of macrophages and lymphocytes in mice treated with a carcinogen, N-butyl-N-butanolnitrosoamine

ICR mice were treated with a carcinogen, N-butyl-N'-butanolnitrosoamine BBN), every day for 8 consecutive weeks and the effects of oral administration of edible mushrooms on the induction of urinary bladder carcinoma and on the activities of macrophages and lymphocytes were studied. Bladder carcinoma were found in all 10 mice (100%) treated with BBN alone, while we observed carcinoma only in 9 of 17 mice (52.9%), in 7 of 15 mice (46.7%) and 13 of 20 mice (65.0%) treated with Lentinus edodes, Grifola frondosa and Pleurotus ostreatus, respectively. Chemotactic activity of macrophages was suppressed in mice treated with BBN alone but maintained almost the normal level in mice treated with BBN plus Lentinus, Grifola or Pleurotus. Lymphocytes collected from mice treated with BBN plus each mushroom showed almost normal blastogenic response against concanavalin A, although those from mice treated with BBN alone completely retarded their response. Cytotoxic activity of lymphocytes against Yac-1 cells was also maintained at a normal level in mice treated with BBN plus each mushroom. Whereas in mice treated with BBN alone significant depression of NK cell activity occurred. Significantly higher cytotoxic activity against P-815 cells was observed in lymphocytes from mice treated with BBN plus each mushroom than that in lymphocytes from normal mice or mice treated with BBN alone.

Effects of Chinese herbs on macrophage functions in N-butyl-N-butanolnitrosoamine treated mice

We investigated the effect of Chinese herbs Lithospermi radix, Astragali radix and Cnidii rhizoma on the functions of macrophages obtained from mice treated with the carcinogen N-butyl-N-butanolnitrosoamine (BBN). The chemotactic activity of murine macrophages was significantly decreased by 17 weeks of treatment with BBN compared with controls. Production of IL-1 and TNF was also markedly reduced. Treatment with Lithospermi radix, Astragali radix, and Cnidii rhizoma significantly inhibited BBN-induced suppression chemotactic activity and production of IL-1 and TNF-alpha by macrophages. Moreover, we found that Astragali radix treated macrophage chemotaxis, it or Cnidii rhizoma induced productions of TNF-alpha were in excess of control.

Effect of shi-ka-ron on cytokine production of lymphocytes in mice treated with cyclophosphamide

The effect of Shi-ka-ron (CX) on cytokine production of lymphocytes in mice treated with cyclophosphamide was investigated. Shi-ka-ron, a traditional Chinese prescription, consists of 8 crude Chinese herbal extracts. Its main efficacy is to strengthen the body resistance. We observed that each CX component stimulated interleukine-2 and interferon-gamma production of murine splenic lymphocytes both in vitro and in vivo. IL-2 and IFN-gamma production of splenic lymphocytes were also examined in mice treated with CX combined with cyclophosphamide (CY) in vivo. We found that CX not only could increase IL-2 and IFN-gamma production in vitro, but also in vivo at suboptimal concentration.

Release of superoxide radicals by mouse macrophages stimulated by oxidative modification of glycated low density lipoproteins

Diabetic patients have high levels of glycated LDL. Although glycated LDLs are implicated in the development of atherosclerosis in such patients, convincing data are lacking. We observed release of superoxide radicals (O2-) from mouse resident peritoneal macrophages stimulated by an oxidized/glycated LDL by using a highly sensitive and specific chemiluminescence method. Oxidized/glycated LDL was achieved by an addition of low concentration of Fe3+ to glycated LDL. Macrophages took up an appreciable amount of the glycated LDL oxidized by iron, leading to the development of foam cells, while they did not take up untreated glycated LDL or the native LDL. These observations clearly indicate that the oxidized/glycated LDL reacts well with macrophages. Since an oxidation of glycated LDL may occur in vivo, the oxidized/glycated LDL might play an important role in atherogenesis.

[Immunomodulative effects of Chinese herbs in mice treated with anti-tumor agent cyclophosphamide]

Extracts of Chinese herbs were administered with antitumor agent, cyclophosphamide (CY), and their effects on macrophages and lymphocytes were studied. Number of peritoneal macrophages significantly decreased and their chemotactic activity was suppressed by treatment with CY. Blastogenic responsiveness to Concanavalin A and NK cell activity of spleen lymphocytes were suppressed significantly in CY-treated mice. Extracts of Lithospermi radix, Astragali radix and Glycyrrhizae radix showed protective effects on immunosuppressive mice. The number of macrophages, chemotactic activity of macrophages and blastogenic response of lymphocytes were recovered to the same or more than that of normal levels. An extract of Ginseng radix showed protective effects on the number and functions of macrophages by treatment with CY but did not show any effects on the lymphocytic blastogenesis. On the contrary it showed a strong inhibitory effect on the NK cell activity. These results suggest that Chinese herbs could modulate cellular immune response, especially in the activation of macrophages and splenic lymphocytes.

Epidemiologic analysis of spatial clustering of bovine ephemeral fever outbreaks. II. Principal component analysis

The principal component analysis (PCA) was applied to analyze a correlation matrix of three variables on epidemic data of bovine ephemeral fever (BEF) outbreaks. These original data were summarized from the official outbreak report of Fukuoka Prefecture. The first and the second principal components of the PCA were interpreted as the infectious potency due to BEF virus and the prevention against BEF virus infection, respectively. The BEF outbreak areas were able to be classified epidemically into 4 groups by using the two principal components. The valuable epidemiological insights can be reasonably obtained from an application of the PCA. The results provided an important information for a further BEF vaccination campaign in the western part of Japan.

Effect of shi-ka-ron and Chinese herbs on cytokine production of macrophage in immunocompromised mice

Shi-Ka-Ron is a prescription composed of 8 crude extracts of Chinese herbs. It reduces suppression of cytokine production by peritoneal macrophages in mice Immunocompromised by the anti-tumor agent, cyclophosphamide (CY), in vivo. Although it dose not increase IL-1 production in vitro, it enhances TNF production. We found that Ginseng radix, Lithospermi radix, Astragli radix and Glycyrrhizae radix somewhat reduced suppression of cytokine production in CY treated macrophages. Especially, Glycyrrhizae radix shows an active immune response both in vivo and in vitro. Our results suggested that the mechanism underlying immunomodulation of Shi-Ka-Ron is closely related to cytokine production: each herb stimulating macrophages.

Immunological properties of TtT/M-87 cell line established from murine pituitary tumor-associated macrophages

TtT/M-87 cell is a macrophage cell line established from thyrotropic pituitary tumor tissues in mouse. In this paper, we report the immunological properties of M-87 cells as a model of tumor-associated macrophage. Contrasting with resident peritoneal macrophages, M-87 cells constitutively secreted small but significant amounts of TNF-alpha and IL-1 alpha, which were detectable in both biological assays (cytotoxic activity for L929 and co-mitogenic activity for Con A-induced T cell proliferation, respectively) and ELISA, and produced larger amounts of these cytokines upon stimulation with LPS. They expressed MHC class II molecules on their cell surface without stimulation by IFN-gamma. The accessory or antigen-presenting cell activity in antibody-producing response of spleen lymphocytes to sheep red blood cells was shown to be much higher in M-87 cells than normal peritoneal macrophages. In addition, when normal spleen lymphocytes were cultured with allogeneic tumor cells, such as EL-4 and S-180, in the presence of M-87 cells, lymphocytes reactive to stimulator cells were activated to manifest inhibitory effect on the tumor cell growth and also to manifest specific cytotoxic effect on the allogeneic tumor cells. These results show that M-87 cells derived from tumor-associated tissue are activated macrophages and that they are inhibitory to tumor cell growth and augmentative in the induction of T-cell-mediated immune responses.

[In vitro induction of chlorhexidine- and benzalkonium-resistance in clinically isolated Pseudomonas aeruginosa]

A study was made on the MIC distributions of chlorhexidine and benzalkonium chloride against clinically isolated 178 strains of Pseudomonas aeruginosa to find out the existence of strains resistant to those disinfectants and also on the in vitro induction of resistance to both drugs. The MIC of chlorhexidine gluconate was found to be distributed from 78 to 625 micrograms/ml with a single peak at 312 micrograms/ml. All 178 strains of clinical isolates were sensitive to chlorhexidine and none could be induced to become chlorhexidine resistant in vitro, suggesting that P. aeruginosa can not easily acquire chlorhexidine resistance. On the other hand, the MIC of benzalkonium chloride was distributed in two peaks; one peak was benzalkonium sensitive at 625 micrograms/ml (150 strains/178 strains: 84.3%) and the another peak was benzalkonium resistant at 5,000 micrograms/ml (28 strains/178 strains; 15.7%). Six (4.0%) of the 150 benzalkonium sensitive strains acquired benzalkonium resistance by in vitro induction of resistance; the MIC of 5 strains increased from 625 micrograms/ml to 2,500 micrograms/ml and that of the residual 1 strain increased from 312 micrograms/ml to 1,250 micrograms/ml. However, no change of MIC was observed in 28 benzalkonium-resistant strains of clinically isolated P. aeruginosa by in vitro resistance induction. Strains with MIC more than 5,000 micrograms/ml could not be obtained at all. The results suggest that the benzalkonium resistance can be introduced in P. aeruginosa whereas the resistance-acquiring rate is low. These results suggest that chlorhexidine gluconate is the first choice for prevention of Pseudomonas infection in the hospital and benzalkonium is also useful in 0.5% solution is used.

Epidemiologic analyses of spatial clustering of bovine ephemeral fever outbreaks. I. Application of the negative binomial distribution

An epidemic that propagates through a population results in a contagious spatial pattern. The incidence per farm of bovine ephemeral fever (BEF) outbreaks in the 22 areas of Fukuoka Prefecture in 1988 was well explained by the negative binomial distribution, which is generally considered, as the clustering of the outbreaks. Furthermore, the clustering was analyzed with three categories of vaccination rate (No. 1-40%, and 40-80%). As a result, the no vaccination and high vaccination rate (41-80%) groups tended to shift to similarly the Poisson distribution. It may be speculated that an insufficient vaccination control of the BEF was influenced with the clustering.

[Relationship between hand-washing activity of disinfectants and in vitro bactericidal activity in the presence of peptone]

A study was made on the relation between in vitro bactericidal activity against Staphylococcus epidermidis which is the main bacterial flora of skin and the disinfecting activity of hand-washing with povidone-iodine, sodium hydrochloride, chloramin-T, chlorhexidine gluconate and benzalkonium-chloride. Although the bactericidal activity of povidone-iodine and sodium hydrochloride was significantly high as compared with those of the other three disinfectants, both povidone-iodine and sodium hydrochloride showed no or a little hand-washing effects. In vitro the bactericidal activity of both povidone-iodine and sodium chloride were significantly retarded by the addition of peptone in the reaction mixture. On the other hand, chloramin-T, chlorhexidine gluconate and benzalkonium chloride showed a high disinfecting activity in hand washing in spite of low in vitro bactericidal activity. Moreover, the bactericidal activity of these three disinfectants were not suppressed by the addition of peptone in the reaction mixture. These results strongly suggested that hand washing effect of disinfectant is affected by the protein on the hand and that hand-washing activity of disinfectant should be determined by in vitro bactericidal activity in the presence of peptone.

Characterization of a tick isolate of Borrelia burgdorferi that possesses a major low-molecular-weight surface protein

An unusual strain of Borrelia burgdorferi (DN 127 cl 9-2) that was isolated from an Ixodes pacificus tick did not react with monoclonal antibodies (MAbs) to OspA and OspB surface proteins, which are found in most U.S. strains. The strain exhibited an abundant protein with an apparent molecular weight of 25,000 (25K protein). A MAb, 86 DN-1, that was prepared to the 25K protein was used in studies on the effect of proteases on the intact spirochetes, immune electron microscopy, and Western blot (immunoblot) analyses; the results indicated that the low-molecular-weight protein was an apparent surface protein that was loosely attached to the spirochete. Five tick isolates from California possessed low-molecular-weight proteins in the 20,000- to 25,000-molecular-weight range that reacted with the 86 DN-1 MAb. The 25K protein of DN 127 cl 9-2 was unaffected by prolonged in vitro passage of cultures in BSK II medium, while the low-molecular-weight proteins of the other strains of B. burgdorferi from California either decreased in quantity or became undetectable on long-term in vitro passage.

Anti-tumor effects of the oral administration of the streptococcal preparation OK-432 (PICIBANIL)--the inhibition of carcinogenesis and growth in rats with ENNG-induced gastrointestinal tumors

We examined whether the Streptococcal preparation OK-432, an immunopotentiating agent, increases immunocompetence of the gut-associated lymphoid system (GALS), inhibits gastrointestinal carcinogenesis, and has an anti-tumor effect. 14C-labelled OK-432 was orally and intraperitoneally administered to rats, and the distribution of the agent in various organs then serially evaluated. The concentration of OK-432 in Peyer's patches and mesenteric lymph nodes was higher after oral administration than after intraperitoneal administration, and showed a biphasic pattern peaking at 30 minutes and 5 hours following administration, in the Peyer's patches. With regard to immunocompetence, PHA- and PWM-stimulated blastogenesis of lymphocytes derived from the mesenteric lymph nodes and peripheral blood enhanced, and the helper/suppressor T-cell ratio was elevated after the oral administration of OK-432. Moreover, chemotactic activity of peritoneal macrophages was also increased. ENNG-induced gastrointestinal carcinogenesis was observed in 60 per cent of the rats orally administered OK-432 as compared with 88 per cent of the controls. The 13-month survival rate of the rats with gastrointestinal cancer was 50 per cent in those administered OK-432 as compared with 25 per cent in those administered OK-432 as compared with 25 per cent in the controls. When administered orally, the agent prevented reduction in immuno-competence in the course of carcinogenesis, suppressed carcinogenesis, and prolonged the survival of animals with cancer without any of the side effects associated with injection. The oral administration of OK-432 is thus considered to be an effective non-specific immunotherapy against gastro-intestinal malignancies.

A chemiluminescent probe with a Cypridina luciferin analog, 2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one, specific and sensitive for O2- production in phagocytizing macrophages

When a Cypridina luciferin analog (the title compound) was added to a macrophage suspension in Hank's balanced salt solution (control), the system emitted a weak, but detectable light, which was not altered in the presence of superoxide dismutase. The same system, however, emitted a much stronger light, just after the addition of a trigger, opsonized zymosan. The luminescence was suppressed to the control level in the presence of superoxide dismutase, while it was only slightly influenced, if at all, by NaN3, a scavenger of singlet oxygen and an inhibitor of myeloperoxidase. Some other results obtained also indicate the participation of O2- in the luciferin analog-dependent luminescence in macrophages during phagocytosis.

Purine metabolic enzymes in lymphocytes. IV. Effects of enzyme inhibitors and enzyme substrates on the blastogenic responses of human lymphocytes

Coformycin, which is an inhibitor of adenosine deaminase, significantly inhibited in vitro blastogenic responses of human lymphocytes to both phytohaemagglutinin (PHA) and pokeweed mitogen (PWM), whereas blastogenic responses to bacterial lipopolysaccharide (LPS) were rather enhanced by the addition of coformycin. Blastogenic responses of lymphocytes to PHA and PWM were markedly suppressed by the addition of adenosine, which is a substrate of adenosine deaminase. Allopurinol, which is an inhibitor of xanthine oxidase, inhibited blastogenic responses of human lymphocytes to PHA, PWM, and bacterial LPS. Inosine (a substrate of purine nucleoside phosphorylase) and hypoxanthine (a substrate of xanthine oxidase) showed no or only a small effect on blastogenic responses of human lymphocytes. These results suggest that adenosine deaminase activity is associated with the T-cell response but not with the B-cell response and that the impaired T-cell response in adenosine deaminase deficiency is the result of intracellular retention of adenosine in T cells. The results also suggest that purine nucleoside phosphorylase or xanthine oxidase activity is associated with both T- and B-cell responses.

Synergistic anti-suppressor effect of mini cells prepared from Salmonella typhimurium and mitomycin C in EL 4-bearing mice

The subcutaneous growth of EL4 cells was significantly accelerated when they were injected together with spleen cells collected from mice which had received EL4 cells SC 14 days previously, and all mice died within 18 days after receiving this mixture; 80% of mice which received a mixture of EL4 and spleen cells collected immediately after EL4 graft survived over 40 days. Spleen cells collected 14 days after EL4 graft suppressed the blastogenic responses of normal spleen lymphocytes to concanavalin A, pokeweed mitogen, and lipopolysaccharide of Escherichia coli in a mixed culture system. Acceleration of tumor growth was retarded when EL4 cells were injected together with spleen cells from EL4-bearing mice treated with both Salmonella typhimurium mini-cells and mitomycin C, and 60% of mice survived over 40 days. Blastogenic responses of normal spleen lymphocytes mixed with spleen cells from EL4-bearing mice treated with both mini-cells and mitomycin C were restored almost to control levels. The results suggest that combination treatment with mini-cells and mitomycin C synergistically inhibits the induction of suppressor cells in EL4-bearing mice.

Depression of resistance against Salmonella infection in sarcoma 180-bearing mice and its restoration by Salmonella mini-cells

The reduction of resistance against Salmonella infection was resulted from the reduction of macrophage activities in Sarcoma 180-bearing mice. Mean survival day of S180-bearing mice was markedly reduced to 1.4 +/- 0.5 days after the challenge with 1 X 10(8) of Salmonella typhimurium LT2 cells in contrast with 6.8 +/- 1.9 days of normal mice. Eighty percent of S180-bearing mice died within 14 days after the challenge with 1 X 10(6) of LT2 cells, whereas all of normal mice survived more than 30 days after the challenge with 3 X 10(6) or less of LT2 cells. Chemotactic and O2- producing activities of macrophages collected from S180-bearing mice which were treated with Salmonella mini-cells restored to normal level. Bactericidal activity of macrophages was also restored by the mini-cell treatment. The restoration of the resistance to Salmonella was accompanied with increases of macrophage activities.

Cells participating in immunologic memory induced with RNA from the spleens of immunized mice

Ribonucleic acid (immune RNA, iRNA) extracted from the spleens of mice immunized with heterologous red blood cells induced antigen-specific immunologic memory. The type of cells (T cells, B cells) which participate in immunologic memory induced with iRNA was investigated. Immune RNA-primed T cells cooperated with normal, iRNA-primed or antigen-primed B cells and induced a high IgM response. Immune RNA-primed B cells did not cooperate with normal T cells, but did with iRNA- or antigen-primed T cells. The activities of iRNA-primed T and B cells were antigen-specific.

Synergistic anti-tumor effect of mini-cells prepared from Salmonella typhimurium with mitomycin C in EL4-bearing mice

A statistically significant increase in survival time was observed in EL4-bearing mice after a mini-cell inoculation. However, no case of survival for over 30 days was observed after an EL4 graft in mice treated with mini-cells alone. Fifty percent of the mice survived for 40 days after an EL4 transplantation when the mice were treated with both an IV injection of mini-cells and an SC injection of mitomycin C. The mini-cell injection restored the macrophage chemotaxis activity in EL4-bearing mice but did not restore the lymphocyte activities.

Macrophage activities in sarcoma 180-bearing mice and EL4-bearing mice

Four types of macrophage activities were studied in sarcoma 180-bearing ICR mice and EL4-bearing C57BL mice. Sarcoma 180 cells grow very slowly and do not metastasize, while EL4 cells grow very rapidly and metastasize rapidly to the liver. Chemotactic activity of macrophages was significantly reduced from an early stage in both sarcoma 180-bearing ICR mice and EL4-bearing C57BL mice as compared with that in normal mice. Digestive activity, which was determined by following O2- production by chemiluminescence measurements was also reduced from an early stage in tumor-bearing mice, whereas no reduction of engulfment activity of microorganisms was observed until an advanced stage in both sarcoma 180-bearing mice and EL4-bearing mice. In contrast enhancement activity of macrophages in the blastogenic response of spleen lymphocytes to bacterial lipopolysaccharide was retained at the normal level at the early stage of the tumor graft and was reduced in later stages. These results suggest that activities of Ia-negative macrophages were at first depressed generally in tumor-bearing hosts and later the activities of Ia-positive macrophages were depressed by factor(s) which might be produced by tumor cells.

Enhancing effects of mini-cells prepared from Salmonella typhimurium on anti-tumor immunity in sarcoma 180-bearing mice

The enhancing effect of mini-cells of Salmonella typhimurium which do not contain chromosomal DNA on anti-tumor immunity in mice was studied. The growth of sarcoma 180 cells which were subcutaneously transplanted into ICR mice was significantly retarded in mice treated with Salmonella mini-cells at the same time or 7 days after S180 transplantation, while no or only a little growth inhibition was observed in mice treated 7 days prior to S180 transplantation. Treatment with mini-cells inoculation alone did not increase the survival time of mice that had received intraperitoneal transplants of S180 cells. However, a statistically significant increase of survival time was observed in mice treated with a combination of mini-cells and surgical resection of subcutaneous tumors when S180 cells were injected 7 days after the surgical resection. The injection of mini-cells restored macrophage chemotaxis in S180-bearing mice in which macrophage chemotaxis was greatly retarded but lymphocyte activity was not.

Purine metabolic enzymes in lymphocytes. II. Adenosine deaminase and purine nucleoside phosphorylase activities in the immune response

ICR mice were immunized with sheep red blood cells (sRBC). Both adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in spleen lymphocytes increased faster than the serum antibody titer and reached a peak one week after the immunization. ADA activity increased significantly in T lymphocytes but not in B lymphocytes collected from the spleens of the immunized mice. A statistically significant increase in PNP activity was found in both T and B lymphocytes from the spleens of the immunized mice. Spleen lymphocytes collected from ICR mice which had been immunized with mitomycin C-treated sarcoma 180 (S180) cells one week earlier showed cytotoxic activity against viable S180 cells. Both ADA and PNP activities in spleen lymphocytes of S180-immunized mice increased significantly, and both activities increased in T lymphocytes prepared from spleen of immunized mice. In contrast, an increase was found in PNP activity but not in ADA activity in B lymphocytes. These results suggest that an increase in both ADA and PNP activities may by necessary for the T-cell response in both humoral and cellular immune responses, and that an increase in PNP activity may be necessary for the B-cell response.

Purine metabolic enzymes in lymphocytes. I. Adenosine deaminase and purine nucleoside phosphorylase activities in mouse lymphocyte subpopulations

The distribution of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in lymphoid organs and lymphocyte subpopulations in mice, and the effect of phytohemagglutinin P (PHA-P) and concanavalin A (Con A) on the enzyme activities were studied. ADA activity was distributed equally in cells from all organs used and no mouse strain differences were observed. In contrast, PNP activity varied with the mouse strain, being highest in C57BL/6 mice and lowest in BALB/c mice, and with the organ in ICR mice, being high in peripheral blood lymphocytes and spleen lymphocytes, low in mesenteric lymph node cells and absent or very weak in thymus cells. T and B lymphocytes were prepared from spleen of ICR mice. High ADA activity was found in both T and B lymphocytes, whereas PNP activity in the T lymphocytes was about one-third of that in the B lymphocytes. PNP activity in thymus cells was increased to the normal level of T lymphocytes in the spleens by cultivation without stimulant. The development of PNP activity in thymus cells was partially inhibited by Con A but was not affected by PHA-P. ADA activity in thymus cells was enhanced by in vitro stimulation with PHA-P but not with Con A. In contrast, in spleen lymphocytes the development of ADA activity was enhanced by stimulation with PHA-P and Con A, and that of PNP activity was enhanced by PHA-P but not by Con A.

Spontaneously induced suppressor cells in vitro: nonspecific suppression of in vitro antibody formation

Nonspecific suppressor cells were induced during in vitro culture of normal mouse spleen cells (SPC) using the Marbrook culture system. The suppressor cells inhibited both the primary and secondary antibody-formation responses antigen nonspecifically in vitro, and both IgM- and IgG-responses were inhibited. The supernatants from suppressive precultured cells were not suppressive. The suppressor cells also inhibited the response of allogeneic SPC beyond H-2 compatibility. The induction of the suppressor cells did not require the presence of antigen but required fetal calf serum (FCS) or both FCS and 2-mercaptoethanol (2-ME). The suppressor cells were generated from the nylon-wool adherent, radiation-sensitive T cell population. On the other hand, the suppressor cells were nylon-wool nonadherent, relatively radiation-sensitive T cells. Actively antibody-producing cells were not affected by the suppressor cells. The suppressor cells inhibited the mitogenic responses of normal SPC to phytohemagglutinin-P (PHA), bacterial lipopolysaccharide (LPS) and concanavalin A (Con A). The suppressor cells themselves inhibited the growth of EL4 cells (T-cell leukemia of C57BL/6 mouse origin) and MOPCll cells (B cells, plasmacytoma of BALB/c mouse origin) even at a low effector-to target cell ratio (E:T ratio = 1:1), but did not kill these tumor cells. These results indicate that the target cells of the suppressor cells are both T and B cells, and that the mechanism of action of the suppression is either inhibition of proliferation or inhibition of early events in the course of the immune response.

Induction of IgM memory with RNA from the spleens of immunized mice

Ribonucleic acid (immune RNA, iRNA), extracted from the spleens of mice immunized with sheep red blood cells (SRBC), induced specific immunological memory. The humoral immune responses of iRNA-treated animals were compared with in vivo and in vitro primary and secondary responses, using the haemolytic plaque-forming cell (PFC) assay. IgM antibody formation was markedly higher in iRNA-treated than in any other mice. The effect of iRNA was antigen-specific and similar materials from non-immunized mice had no activity.

Immunopotentiating activity of whole cells and mini-cells of Salmonella typhimurium

Salmonella typhimurium strain 9 produces mini-cells during cell proliferation. Mini-cells are viable but cannot proliferate since they do not contain chromosomal DNA. Effects of whole cells and mini-cells of S. typhimurium on the immune responses were investigated, with the following results. Phagocytosis of peritoneal macrophages was enhanced by in vivo stimulation of both whole cells and mini-cells. Cellular immunity against L1210 cells (mouse leukemia cells) and Sarcoma 180 cells was also enhanced by both whole cells and mini-cells. Mini-cells slightly stimulated in vitro blast cell transformation of normal mouse lymphocytes. Whole cells of S. typhimurium induced antibody-forming cells to produce IgG of higher affinity but mini-cells did not. Mini-cells were not directly cytotoxic for normal lymphocytes or L1210 cells.

Acceleration of allogeneic antitumor immunity with immune RNA in vitro and T-cell suppression by L1210 tumor bearer spleen cells

RNA fractions extracted from the spleens of immunized animals prepared against L1210 leukemia cells can transfer allospecific cell-mediated immunity both in vitro and in vivo. Both preculture of nonsensitized lymphocytes prior to the treatment with immune RNA and additional culture of lymphocytes after 1-hr treatment with immune RNA enhance the growth-inhibitory activity of immune RNA-treated lymphocytes. Preculture for 5 hr and additional culture for 24 hr are sufficient for maximal enhancement of the growth-inhibitory activity. There is no significant difference in inhibition between lymphocytes treated with immune RNA for 1 hr and 24 hr. The growth inhibition by lymphocytes is augmented proportionally to the increase in the dose of immune RNA in vitro but not in vivo. In mice given i.p. injections of immune RNA-treated syngeneic spleen cells (before or after inoculation with L1210 cells), a significant prolongation of the mean survival time [27.0 +/- 5.4 (S.D.) days, 0.05 < p < 0.1] was not achieved when compared with control mice (21.4 +/- 1.6 days). Evidence is presented that suppressor cells in the spleens of L1210-bearing mice are involved in preventing effector cell function in vivo. The present study revealed that 8 X 10(3) and 5 X 10(5) suppressor cells were sufficient to inhibit completely the activity of immune RNA-treated effector cells in vitro and in vivo, respectively. Suppressive activity was abolished by treatment with anti-Thy 1.2 serum and complement and partially abolished with irradiation (1500 R). The suppressor cells belonged to a radiation-sensitive T-cell population. The limited activity of immune RNA in vivo is probably due to the destruction of immune RNA by RNase present in the host plasma and tissues and the acquisition of suppressor cells which inhibits nonadherent peritoneal exudate cell activity in the animal.

Effects of levamisole administration on treatment with 6-mercaptopurine riboside of mice bearing L1210 leukemia cells

DBA/3 mice and BALB/c X DBA/2 F1 mice were inoculated i.p. with 1 X 10(5) L1210 leukemia cells on Day 0. Beginning with Day 1 following inoculation, the animals were given injections of 6-mercaptopurine riboside (200 mg/kg i.p.) once daily for 5 consecutive days in combination with a single s.c. injection of levamisole (LMS) (10 mg/kg). In DBA/2 mice, a marked decrease in the total peritoneal cell count was achieved when LMS was given on any day from Day -2 to 3 as compared with therapy using 6-mercaptopurine riboside alone, although the survival time was not prolonged in these mice. When LMS was given on Day 1 or 3, a decrease was observed in the in vitro growth rate of the L1210 cells obtained on Day 11 from the peritoneal cavity. In BALB/c X DBA/2 F1 mice, no significant changes were observed in either the total peritoneal cell count or the in vitro growth rate when LMS was injected on Day 3 or daily from Day 3 to 5. Daily injection of LMS from Day 1 to 3 resulted in a conspicuous inhibition of the in vitro growth rate, although no significant changes were observed in the total peritoneal cell count. It seems reasonable to conclude from these results that LMS has a potentiating effect on the antitumor activity of 6-mercaptopurine riboside.

Cefroxadine (CGP-9000), an orally active cephalosporin

Cefroxadine (GCP-9000; CXD), 7 beta[D-2-amino-2-(1,4-cyclohexadienyl)-acetamido]-3-methoxy-ceph-3-em-carboxylic acid, is a new orally active cephalosporin derivative. The spectrum of antibacterial activity of CXD is identical with that of cephalexin (CEX), but CXD was twofold more effective than CEX against Escherichia coli and Klebsiella pneumoniae, CXD was as stable to penicillinase as CEX, but it was hydrolyzed by cephalosporinase, with a relative rate of hydrolysis similar to that of CEX. The affinities of CXD and CEX to penicillin-binding proteins of E. coli were estimated; the affinity of CXD to penicillin-binding protein 1Bs was higher than that of CEX. Consistent with this, CXD had more intensive lytic activity than CEX. In vivo antibacterial activities of CXD and CEX were compared using systemic infections of mice with E. coli and K. pneumoniae; CXD was consistently more active than CEX.

In vitro and in vivo antibacterial activity of KW1070, a new aminoglycoside antibiotic

KW1070, a new aminoglycoside antibiotic with the novel aminocyclitol, fortamine, has a broad spectrum of activity in vitro and in vivo against gram-positive and gram-negative bacteria. The minimum inhibitory concentrations of KW1070 are similar to those of kanamycin against aminoglycoside-susceptible strains, slightly less than those of gentamicin or 3',4'-dideoxykanamycin B. Minimal bactericidal concentrations were found to be near minimal inhibitory concentrations. KW1070 was active in vitro against many aminoglycoside-resistant bacterial strains that possess aminoglycoside-inactivating enzymes, particularly AAC(6'), AAC(2'), AAD(2''), and APH(3'). The activities of KW1070 in mice infected with Staphylococcus aureus, Escherichia coli, Proteus sp., and Serratia marcescens compared favorably with the activities of amikacin and kanamycin; KW1070 was also singificantly active in mice infected with resistant strains bearing the aminoglycoside-inactivating enzymes listed above.

In vitro and in vivo antibacterial activity of AB206, a new naphthyridine derivative

AB206 (5,8-dihydro-5-methoxy-8-oxo-2H-1,3-dioxolo-4,5-g quinoline 7-carboxylic acid) is a novel antibacterial agent structurally related to nalidixic acid. AB206 has potent antibacterial activity against clinical isolates of gram-negative bacteria and is 4 to 18 times more active than nalidixic acid. AB206 inhibited the growth of Staphylococcus aureus and Pseudomonas aeruginosa, which were resistnat to nalidixic acid. Cross-resistance was not observed between AB206 and various antibiotics, and most bacterial strains resistant to nalidixic acid were susceptible to AB206. AB206 showed bactericidal activity against Escherichia coli, Proteus, Klebsiella pneumoniae, and P. aeruginosa. Chemotherapeutic effects after oral administration of AB206 in mice experimentally infected with E. coli, K. pneumoniae, and Proteus morganii showed that AB206 was two to four times more potent than nalidixic acid.

Determination of the ID50 values of antibacterial agents in agar

Microorganisms were plated on agar plates containing various concentrations of an antimicrobial drug and inhibition of growth was determined at each drug concentration. The ID50 value and the gradient of the line were calculated by the least square method. When 200 approximately 800 bacterial cells were inoculated on an agar plate, growth inhibition corresponded linearly with the log concentration of a drug within range of 5 approximately 95% inhibition. The ID50 value and the gradient obtained were reproducible and reliable using microorganisms at stationary phase of growth with all tested bacterial species and all tested antimicrobial agents. It was found that the ID50 values of drugs were more reproducible and may be more reliable than the MIC (minimum inhibitory concentration) values of the drugs.