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The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells.  相似文献   
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An immunoglobulin (Ig) production stimulating factor (IPSF) for hybridomas was found in spent medium of the human B lymphoblastoid cell line, HO-323. The IPSF was purified by serial use of DEAE chromatography, ultrafiltration, gel filtration and HPLC-DEAE chromatography. Purified IPSF was estimated to be a 410 k macro molecule by gel filtration, and contained three types of isomers which were separated from each other by native polyacrylamide gel electrophoresis. All of the isomers were, however, assumed to have the same protein components by SDS polyacrylamide gel electrophoresis.The IPSF was effective for human-human and mouse-mouse hybridomas producing IgM, but not for IgG producers in the experimental condition used here. Human-human hybridoma HF10B4, cultured in IPSF-containing medium, produced 20 times more IgM than in IPSF-free medium under serum-free conditions. The IPSF showed very little proliferation stimulating activity on HF10B4 cells.  相似文献   
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A 51-yr-old Japanese female patient with monoclonal IgM gammopathy with rheumatoid factor activity was admitted because of pneumococcal bacteremia. About 2 wk after admission, her rheumatoid factor activity became undetectable by RAHA test and radioimmunoassay, subsequent to the initial marked elevation. The suppressive capacity of the patient's IgG fraction on the rheumatoid activity of her monoclonal IgM on January 11 was determined. The IgG fraction obtained on February 22 blocked the binding of the rheumatoid factor to rabbit IgG. The suppressive activity in the IgG fraction of February 22 was shown to be localized within the F(ab')2 fragment. Furthermore, the specificity of the suppressive serum factor was shown by the inability to block the binding of SRBC coupled with diazotized phosphorylcholine to anti-pneumococcal antibody. Thus, the marked reduction of rheumatoid factor activity was considered to result from anti-idiotypic antibody transiently appearing in her serum after pneumococcal bacteremia.  相似文献   
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Aboveground biomass and litterfall ofPinus pumila scrubs, growing on the Kiso mountain range in central Japan, were investigated from 1984 to 1985. The biomass of two research plots (P1 and P2) with different scrub heights was estimated by two methods, the stratified clip technique and the allometric method. Aboveground total biomass estimated by the latter method reached 181 ton d.w. ha−1 in P1 and 132 ton d.w. ha−1 in P2. Creeping stems contributed to about half of the total biomass. Although estimates of woody organs differed between the two plots, leaf biomass estimates were almost the same at 15.5 ton d.w. ha−1. The canopies of the twoP. pumila scrubs were characterized by a large mean leaf area density of 5.0 m2 m−3. Despite this large area density, relatively moderate attenuation of light intensity was observed. Specific leaf area generally increased with reduced leaf height. Annual total litterfall was estimated to be 3.60 ton d.w. ha−1 yr−1 in P1 and 2.39 ton d.w. ha−1 yr−1 in P2. Annual leaf fall in both plots was approximately 2.0 ton d.w. ha−1 yr−1. Leaves fell mainly in early autumn. Annual loss rates of branches, estimated as the sum of annual branch litterfall and the amount of newly formed attached dead branches, were 0.29 ton d.w. ha−1 yr−1 in P1 and 0.37 ton d.w. ha−1 yr−1 in P2.  相似文献   
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IL-7 induced the proliferation of normal thymocytes and the effect was synergistically potentiated by a small dose of IL-2, which by itself hardly affected thymocyte proliferation. No synergism was observed between IL-7 and any one of the other lymphokines including IL-1, IL-3, and IL-4. The thymocyte culture stimulated with IL-7 and IL-2 consisted of single positive (CD4+CD8- and CD4-CD8+) and double negative (CD4-CD8-) populations, and double positive (CD4+CD8+) cells were completely deleted. Both single positive and double negative thymocytes expressed CD3, but only the former exhibited V beta 8 and V beta 6 in an expected proportion (approximately 30% in BALB/c mice) and the latter none at all. Immunoprecipitation of the cultured thymocytes by anti-TCR gamma antibody, on the other hand, revealed the presence of a TCR gamma chain. Taken together, these results indicated that the thymocyte cultured with IL-7 and IL-2 consisted of mature T cells bearing alpha beta or gamma delta TCR. Experiments using preselected thymocyte subpopulations indicated that double negative cells responded to both IL-7 and IL-2 with positive synergism when combined, while thymocytes enriched for single positive cells preferentially responded to IL-7 with little response to IL-2 and no detectable synergism. Double positive thymocytes showed no proliferation in response to IL-7 and IL-2. In contrast to single positive thymocytes, splenic T cells hardly responded to IL-7, although significant proliferation was induced in the presence of a low dose of IL-2. Thymocytes cultured with IL-7 and IL-2 showed little nonspecific cytotoxic activity, but responded to Con A or alloantigen, whereas those stimulated with a high dose of IL-2 alone exhibited potent cytotoxic activity. These results indicated that IL-7 was involved in the generation of immunocompetent T cells in the thymus in concert with IL-2.  相似文献   
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