
We reported previously that footpad reaction (FPR) of BALB/c mice against sheep red blood cells (SRBC) was suppressed by the percutaneal administration of 12-tetradecanoyl 13-acetate (TPA), a tumor promoter, following that of 7,12-dimethylbenz[a]anthracene (DMBA), a tumor initiator. This effect could be transferred with Thy-1(+) and Lyt-2(+) spleen cells. These findings suggested that this effect was caused by induction of the antigen nonspecific T-suppressor cells and that the process of the induction consisted of two steps. In the present report, we studied the cells related to the first step of this process. The spleen cells from the donor mice on which 400 nmol of DMBA was painted were transferred to the recipient mice which had been immunized 1 hr before the transfer. Then, 8 nmol of TPA was painted on the recipient mice every day for a week. Nine days after the transfer, FR against SRBC was measured. FPR in the recipient mice was suppressed compared to the control, showing that the effect of DMBA can be transferred with the spleen cells. The results of the treatment of the cells to be transferred with monoclonal antibodies and complement show that the cells which is responsible for the transfer of the effect are Mac-1(+), Thy-1(-), Lyt-2(-) and Ia(-). Also the effect of DMBA could be transferred with peritoneal macrophages from the donor mice on which DMBA was painted and anti Ia antibody treatment of the macrophages did not abrogate the effect of transfer.(ABSTRACT TRUNCATED AT 250 WORDS)
The morphological patterns of rejection of the heart allografts which were combinedly transplanted with skin grafts was examined to determine whether it was different from that of the heart grafts transplanted alone. The results showed that there were distinct differences in the pathology of the rejection between the two groups because in the single heart grafts mononuclear cells concentrated in almost all layers of myocardium but in the combinedly transplanted heart grafts not only concentration of them but also severe hemorrhage and edema were observed in it, and it suggests that skin graft has effects on rejection process of heart grafts. As we used an outbred strain of rats some survived heart grafts were observed and their pathology was characteristic in the interstitial accumulation of hypertrophic mast cells, most of which were degranulating.
In the epidemiological surveys on scrub typhus at Chichibu City near Tokyo, an area, 350 m by 35 m, in the Hitsujiyama Park was found to be heavily infested with Rickettsia tsutsugamushi (Rt). Distribution of trombiculid mites and their infection rates in this area were studied using sentinel animals, 48 Microtus montebelli and 10 ddY mice. The surveys were conducted 6 times in the autumn in 1985 and 1986. At the first 2 surveys, 16 animals were placed at random, and 4 restricted areas were identified as highly populated with trombiculid mites. For the detailed survey, each of 4 areas was divided into 2 m x 2 m quadrats to settle a sentinel animal to each. A total of mites collected by all sentinel animals was 331 Leptotrombidium pallidum, 175 L. fuji and 16 Gahrliepia saduski. Almost all mites were collected by M. montebelli, except only 1 L. fuji in 10 mice. From a M. montebelli in a quadrat, 157 L. pallidum were recovered, whereas the number/vole was 0 to 24 in the others. L. fuji was also highly aggregated at 2 sites. Rt was detected from individual mites by avidin-biotin immunofluorescence or isolated by the mouse passage from individual or pooled mites. Only Karp strain of Rt was detected or isolated from L. pallidum at a ratio of 31/286 (10.8%). No Rt was found from L. fuji or G. saduski. The infection rate in L. pallidum was especially high in 3 voles at ratios of 6/11, 2/5 and 3/5, respectively. Out of 14 sentinel M. montebelli with infected L. pallidum, 12 (85.7%) were infected with Rt. It was concluded that L. pallidum was distributed in aggregated clusters to form the mite islands and was infected heavily at the specific sites to make the infective spots.
The expression of the erbB-2 gene product was studied immunohistochemically on 38 normal colonic mucosae, 14 adenomas and 44 colon cancers, with the use of two anti-erbB-2 antibodies, a rabbit polyclonal antibody specific for the intracellular domain and a mouse monoclonal antibody specific for the extracellular domain. Normal mucosae and adenomas were not stained. Five cases (11%) of colon cancer were positive with the polyclonal anti-erbB-2 antibody, while only one case was positive with the monoclonal antibody. Most of the positive cases were in Dukes C stage. The rare overexpression of the erbB-2 protein in colon cancer seems to indicate a minor role for the gene in colorectal tumorigenesis.
A comparative study of specific and non-specific immunosuppression has been carried out in acute and chronic Plasmodium berghei infected mice in an in vivo system. In our previous studies, immunosuppression during acute P. berghei infection was attributed to T lymphocytes when we studied modulation of blastogenic response of lymphocytes in an in vitro system. In the present study, delayed type hypersensitivity (DTH) was evident from the homing of radiolabelled bone marrow cells into the delayed lesions of antigen challenged foot pads during chronic infection. This response was suppressed during acute infection especially in early stages. A greater concentration of bone marrow cells in the liver and spleen occurred during chronic infection in comparison with acute infection. When radiolabelled bone marrow cells from infected mice were injected into the normal mice previously given malaria antigen in foot pads, no significant change in homing pattern in liver, spleen or foot pads was observed. Contact sensitivity to picryl chloride was suppressed during acute infection, but was intact during chronic infection. Since these responses are mediated by T lymphocytes, significance of these responses is discussed.
T-2 toxin (T-2(4)), one of the trichothecene mycotoxins produced by various gerera of Fusarium spp., is a potent inhibitor to the syntheses of protein and DNA in mammalian cells. The selective cytotoxicity of T-2 toxin-conjugated anti-EL-4 monoclonal antibodies (T-2-mAb) was investigated against murine thymoma EL-4 cells in vitro and in vivo systems. At first T-2 was converted to T-2 hemiglutarate by glutaric anhydride. Then T-2 hemiglutarate was activated to 3-[4-(N-succinimidoxycarbonyl)-butyryl]-T-2 (T-2-G-OSu) by N-hydroxysuccinimide. Thus obtained T-2-G-OSu was conjugated with mAb specific for EL-4 cells. The T-2-mAb markedly inhibited the proliferation of cultured EL-4 cells, but no such cytotoxic effect was observed against irrelevant SP2/0 cells. The cytotoxicity of T-2-conjugated normal gamma globulin (T-2-nGG) against EL-4 cells was far less than that of the above T-2-mAb. Ammonium chloride and monensin, inhibitors of lysosomal enzymes, enhanced the cytotoxicity of T-2-mAb. The presence of both 2-deoxyglucose together with sodium azide, inhibitors of energy-dependent reaction, reduced the cytotoxicity of T-2-mAb. Therefore, the selective binding to the target cells followed by an energy-dependent endocytosis and an intracellular liberation of T-2 by hydrolysis may account for the cytotoxicity of the T-2-mAb. In mice pre-transplanted with EL-4 cells, T-2-mAb increased the mean survival time (MST) with a direct dosage dependence.(ABSTRACT TRUNCATED AT 250 WORDS)
On weeks 7 and 9 post infection (PI), the number of Schistosoma japonicum in mice maintained at low (5 degrees C) and high (32 degrees C and 35 degrees C) temperatures did not differ from those in controls (25 degrees C), but shorter males were observed in hosts at 5 degrees C. Further, both male and female worms recovered on week 7 PI from mice kept at 35 degrees C were shorter than those recovered from controls. Staining analysis revealed that worm maturation was not affected in mice kept at 5 degrees C and 32 degrees C. However, some female worms from mice kept at 35 degrees C had no eggs in the uterus. The day of patency of worms in the temperature-stressed mice did not differ from that in controls. EPG in mice kept at 32 degrees C rose to a high level on weeks 7-8 PI which was about 10 times as many as those in control mice, while EPG in mice kept at 5 degrees C appeared to be lower than in controls. The 7-week tissue egg count revealed that the hot- and cold-stressed mice supported significantly less egg productivity per female worm than control mice. The environmental temperature could not alter the migration pattern of schistosomula from the skin to lungs in mice.
The Nansei Islands are located in the subtropical zone of the western Pacific Ocean between Kyushu and Taiwan, and are composed of the two main island groups, the Amami and the Ryukyu Archipelagoes. This area has been known for the presence of a number of indigenous animal species. Prior to the present studies, collections of the chironomids mainly in the urban areas of the three main islands of the Ryukyus were carried out by Sasa and Hasegawa, and a total of 42 species, including 25 new species, were recorded. Additional collections of the chironomids mainly in the mountainous areas of this region were carried out by the present author during 1988 and 1989, and a total of 26 species (including 12 new species) were recorded from Amami Island, and a total of 27 species (including 10 new species) were recorded from the Ryukyu Islands. Eight species among them, including 3 new species, were common to the two archipelagos.
Filarial glomerulonephritis was studied using Dirofilaria immitis infected dogs. Of 34 infected dogs examined, 15 dogs (44.1%) had histopathological lesions in the kidney. These lesions included an increased number of mesangial cells and increased thickness of the matrix, the infiltration of the small round and plasma cells into the interstitium and thickening of the basement membrane. Deposits of IgG were demonstrated in the infected dogs, whereas C3 deposits were found in all dogs. Combined immunoglobulin and complement deposits were not always found in the dogs with histopathological lesions. The mean concentration (expressed as absorbance) of circulating immune complexes (CIC) was 0.675 +/- 0.517 in infected dogs, and 0.132 +/- 0.092 in uninfected dogs. Although there was significant difference in the level of CIC between infected and uninfected dogs (P less than 0.001), 11 dogs (32.4%) in infected group were negative. Otherwise, the CIC levels were correlated to the adult worm burden (r = 0.848; P less than 0.001) but not to the number of circulating microfilariae (mf) (r = 0.398; P less than 0.05). Transfer of mf to 7 naive dogs was performed to clarify the role of mf in the pathogenesis of filariasis. Antibodies to crude mf antigen became detectable two weeks after the transfer. Neither pathologic findings nor deposits of IgG and C3 in the kidney were found in dogs examined 20 days or 70 days after transfer. There was no evidence that histopathological lesions were induced by live mf, suggesting that adult worm burdens may be more closely related to filarial nephropathy.
Transmission of Rickettsia tsutsugamushi (Rt) from a rodent to trombiculid mites was studied. Wild rodents, Apodemus speciosus, were subcutaneously inoculated with Karp strain of Rt, and larval trombiculid mites were released on the ear lobes for feeding, 10 and 20 days after infection. Isolation of Rt was performed from individual mites or pools of 2 to 7 mites by the mouse passage method. From Apodemus 10 days after Rt infection, possibly at the time of high rickettsiaemia, the infection rates among mites were 4/44 (9.1%) or higher in Leptotrombidium fuji, 1/20 (5%) in L. pallidum and 0/41 in L. deliense. From Apodemus 20 days after infection, no mite was infected in 50 L. fuji or 7 L. pallidum possibly due to reduced rickettsiaemia. Transmission of Rt from rodent to mite was proven to occur at low probability on appropriate conditions but not by the incidental chance.
The effects of heating on the morphology and cell cycle of ascites hepatoma AH-100B cells were investigated. Five rats with AH-100B ascites cells were warmed in a water bath at 39 degrees C, 41 degrees C, or 43 degrees C, respectively. After heating, changes in the morphology of tumor cells were observed every day over a 3-day period under a light microscope and changes in the nuclear DNA content were measured by microspectrophotometry. Morphologic changes in AH-100B cells, which included swelling and vacuolization of the cytoplasm and constriction, vacuolization and destruction of nuclei, were observed. Multinucleated giant cells were characteristically observed in the cells from rats heated to 43 degrees C. In the case of rats heated to 43 degrees C, an increase was seen in the number of cells with a DNA content of 8C to 10C, and some of the cells exhibited polyploidy with a DNA content greater than 10C. It appears that one of the mechanisms of the antitumor effect of hyperthermia in vivo involves changes in the cell cycle of cancer cells and the accumulation of polyploid cells.
IgM and IgG natural antibodies to Tamm-Horsfall glycoprotein (THP) were found in serum samples of all healthy individuals tested by the ELISA technique. The IgM anti-THP antibody level was higher in the group 1-20 years old than the IgG anti-THP. The IgG anti-THP rose with increase in age (greater than 21 years old groups) and then the IgG and IgM anti-THP activity over aging remained constant. The natural anti-THP antibodies possess a lower degree of specificity and/or avidity than induced antibodies. The antibody titers against THP determined in 61 adult patients with chronic kidney diseases was significantly lower than that in adult controls. This low level of naturally occurring THP antibodies appears to be a general phenomenon. In these patients, diminished antibody levels appeared against a panel of self (collagen, fibronectin, THP) and non self (bovine gamma globulin (BGG), ovalbumin (OVA)) antigens as compared with normal controls. The low levels of these antibodies are not associated with a concomitant drop of IgG and IgM in their sera.
To examine the roles of oxygen free radicals in the inhibition of tumor cell proliferation, we have used disulfiram (DS), a metal-chelator, to inactivate superoxide dismutase and ascorbic acid (AsA) to inhibit catalase. Simultaneous addition of DS and AsA to Meth A tumor cells or Ehrlich ascites tumor cells induced marked inhibition of the cell proliferation assessed by [3H]thymidine uptake and trypan blue dye exclusion method. Similar augmented inhibition of Meth A tumor cell proliferation was observed when the cells were pretreated with DS and AsA. However, the addition of catalase (2000 u/ml) nullified the augmentation of anti-proliferative effect which can be induced in the combined use of DS and AsA. These results suggest that the steady-state increase of intracellular oxygen free radicals within tumor cells could be induced in the combined use of DS and AsA.
The aorta and the kidney of 12 month old hyperlipidemic WHHL and obese Zucker rats, were examined morphologically. The WHHL developed severe and premature atherosclerosis but did not develop glomerulosclerosis. In contrast, the Zucker rats did not manifest atherosclerosis of the aorta, but developed glomerulosclerosis. These two animal models could be useful in understanding the roles of heterogeneous lipoprotein particles, genetic susceptibility, hemodynamic stress, and mesangial interactions with lipoproteins in the development of glomerulosclerosis.