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91.
In an ultrastructural study of 37 cases of bronchioloalveolar cell carcinoma (BAC), we identified seven cases (19%) in which Langerhans cells (LC) were closely associated with tumor cells. Serum precipitating antibodies against Aspergillus species and/or thermophilic actinomyces were present in five BAC patients whose tumors contained LC and in six patients whose tumors lacked LC. In a simultaneous study we identified marked atypical bronchiolar and alveolar lining cell hypertrophy and hyperplasma in pulmonary eosinophilic granuloma (PEG). Our data plus current information suggesting that PEG is a form of hypersensitivity pneumonitis support our hypothesis that those cases of BAC in which LC are present may arise in localized or diffuse pulmonary scars caused by PEG.  相似文献   
92.
Todja is a secluded region of northern Tuva situated in the Sayany Mountains, Siberia. The aboriginal population of Todja is Tuvan. A total of 128 healthy Tuvans living in Todja were typed for HLA-A, -B and -C antigens and several plasma and erythrocyte protein polymorphisms (Hp, Tf, Gc, ESD, ACP, PGM1, PGD and ADA). The observed frequencies of all 8 blood protein and HLA genotypes were in agreement with Hardy-Weinberg expectations. The most frequent HLA antigens in Todjans are A2 (0.36). A3 (0,24), A9 (0.50), B15 (0.34) and B40 (0.50). HLA haplotypes A2B5, A2B40, A9B15 and A9B40 are most common in this population. The observed frequencies of protein polymorphisms and HLA antigens and haplotypes in Todjans are similar to those of other Mongoloid populations. A comparison of HLA frequencies currently observed in Todjans with those obtained 20 years ago at the same locality showed minor changes attributable to the effect of migration.  相似文献   
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Summary Carcinoembryonic antigen (CEA),-human chorionic gonadotropin (HCG), alpha-1-antichymotrypsin (ACT), alpha-1-antitrypsin (AAT) and Lysozyme (LYS) were traced by immunoperoxidase staining in gastric carcinomas. The immunohistological results were evaluated in relation to histological types (WHO and Laurén), stage of disease, grade and survival time. CEA was demonstrated in 96% of the tumours, HCG in 34%, ACT in 78%, AAT in 42%, and LYS in 71%. Comparing the staining patterns of the antigens and the intensity of staining some differences were notable. Except for signet-ring cell carcinomas, all of which were intensively positive, CEA expression decreased significantly with loss of differentiation. This observation was not seen with the other marker substances. None of the tested markers was characteristic for one particular histological type, nor could they be correlated with the tumour stage or grade. The marker positivity of CEA, ACT and LYS was not related to survival time. For HCG only, a correlation between tissue expression and a restricted survival time was established. Patients with AAT positive carcinomas had a significantly better survival probability.  相似文献   
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Patients with chronic mucocutaneous candidiasis (CMC) succumb to persistent infections with the opportunistic yeast Candida. Impaired cell-mediated responses to Candida have been repeatedly reported while antibody responses were mostly found to be normal. The underlying defect remains poorly understood. It has recently been shown that CMC patients are also susceptible to infections with encapsulated bacteria, and may have associated IgG2 and IgG4 deficiency. Our previous studies demonstrated altered cytokine production in CMC patients. As cytokines can influence production and isotype of specific antibody, in 10 patients with CMC we measured the levels and isotype distributions of serum antibodies to Candida antigens (CAg), pneumococcal polysaccharide (PPS) and tetanus toxoid (TT) antigens. Peripheral blood lymphocytes were also stimulated in culture and the antibodies made in vitro were measured. Our data demonstrated that in vivo, CMC patients had very high levels of IgG and IgA CAg-specific antibodies. CAg-specific and PPS-specific IgG1 was markedly higher than in controls. Children but not adults with CMC had significantly lower levels of IgG2-specific antibody to CAg and PPS compared with age-matched controls. Patients had significantly higher levels of IgG3-specific antibody to all three antigens tested. These findings were in accordance with increased total IgG and IgG3 levels seen in CMC patients. In vitro, CMC patients, particularly children, did not respond as frequently to antigen stimulation as did their healthy controls. The level of specific antibody produced was also lower to all antigens tested, as was the amount of total immunoglobulins following antigenic and particularly mitogenic stimulation. Addition of interferon-alpha (IFN-α) or IFN-γ to cultures had variable, sometimes marked, effects. Our results demonstrate that CMC patients manifest subtle alterations in specific antibody responses to CAg, PPS and TT, which are most pronounced in children. This may relate to altered cytokine production also seen in these patients.  相似文献   
98.
Our previous studies have disclosed that the peripheral T cell receptor β (TCRB) gene repertoires of RA monozygotic twins were similar. This suggested that the TCRBV repertoire is controlled primarily by genetic factors. Here, we examine how the combination of HLA and presence of RA influence the peripheral TCRB repertoire. Peripheral blood mononuclear cells from six pairs of healthy monozygotic twins, six pairs of monozygotic twins discordant for RA, and nine siblings of a large family, including three RA patients, were examined for their TCRB gene repertoires. Among healthy twins and siblings, the BV repertoires between HLA-identical pairs were significantly more similar than those of HLA-non-identical pairs. When RA-affected members were included, the repertoires of the HLA-identical pairs discordant for RA were dissimilar compared with those of healthy pairs. TCRBV–BJ combination repertoire analysis of CD4 and CD8 T cell subsets from the twins showed that the dissimilarity was primarily confined to CD8 T cells in the healthy identical twins, whereas it was seen in both CD4 and CD8 T cell subsets in the RA-discordant twins. These results suggest (i) the presence of RA modifies the genetically controlled TCR repertoire of peripheral T cells, and (ii) the RA-associated alterations appear to occur more frequently in CD4 T cells than in CD8 T cells.  相似文献   
99.
Cancer metastasis involves distinct steps that depend on complicated tumor–host interactions. The hematogenous dissemination of tumor cells may be facilitated by factors that promote the arrest and adherence of cancer cells in capillaries. We examined whether anti-tumor monoclonal immunoglobulin M (IgM) antibodies promoted the hematogenous dissemination of B16 melanoma cells in syngeneic mice. IgM monoclonal antibodies were generated that selectively bind to B16 melanoma cells as compared to syngeneic fibroblasts, lymphocytes or Lewis lung carcinoma cells. Incubation of B16-BL6 or B16-F0 melanoma cells with these IgM anti-tumor antibodies significantly increased the number of lung colonies as compared with control antibodies. Moreover, intraperitoneal injection of specific antibody also significantly increased lung colonization. All anti-tumor antibodies promoted the aggregation of B16 melanoma cells. A chemically generated immunoglobulin G (IgG)-like fragment of an anti-tumor IgM antibody displayed greatly reduced tumor aggregation and, in contrast to intact IgM, did not significantly increase lung colonization of B16 melanoma cells. Neither intact IgM nor the IgG-like fragment enhanced the in vitro invasiveness of B16 melanoma cells across Matrigel-coated membranes. Our results, therefore, suggest that besides their beneficial anti-tumor effects, anti-tumor IgM antibodies may also promote the hematogenous dissemination of cancer cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
100.
PROBLEM: The unusual pattern of human leukocyte antigen (HLA) expression on human trophoblasts could play an important role in successful pregnancy outcome. To determine whether alterations in HLA expression are associated with pregnancy abnormalities we have investigated expression of these antigens on chorionic and extravillous cytotrophoblasts. METHODS: Frozen tissue sections of placenta and fetal membranes were collected after pre-term spontaneous delivery, severe pre-eclampsia pre-term Caesarean section, normal term delivery and term Caesarean section. HLA expression was analyzed by immunohistochemistry. RESULTS: We did not observe differences in the expression of HLA on chorionic and extravillous cytotrophoblasts in pregnancy abnormalities. However, we noted higher expression levels of HLA class Ia molecules in amnion epithelial cells in pre-term deliveries. Furthermore, in severe pre-eclampsia the number of extravillous cytotrophoblast islands were elevated when compared with pre-term deliveries. CONCLUSIONS: No alterations in expression of HLA class Ia, HLA-G and HLA class II on human trophoblasts in pregnancy abnormalities were seen.  相似文献   
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