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Immunoregulation of B lymphocyte colony formation by T cell subsets in patients with chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
Normal B lymphocytes are activated, proliferate, and then differentiate into plasma cells and secrete immunoglobulin (Ig). We have reported that chronic lymphocytic leukemia (CLL) T4 cells help and CLL T8 cells lack suppressor effects on Ig synthesis by normal B cells (Blood 62:767, 1983). We have now explored the earlier phase, proliferation, using B cell colony formation; in semisolid media. B lymphocyte colonies from normal individuals and from patients with CLL were grown in 0.3% agarose overlayed with T cells or T cell subsets and the B cell mitogen staphylococcal protein A. Enriched T cells, OKT4 or OKT8, were obtained either by sheep erythrocyte rosettes or depletion of OKT8 or OKT4 cells by monoclonal antibody or complement, respectively. Twenty thousand B cells from normal subjects yielded 65 +/- 9, 64 +/- 7, and 19 +/- 6 colonies with autologous unfractionated T-, OKT4-, or OKT8- positive cells, respectively. This compared to 29 +/- 11, 81 +/- 11, and 15 +/- 4 colonies from patients with CLL with added autologous unfractionated T-, OKT4-, or OKT8-positive cells. To determine whether the fewer number of colonies in both normal subjects and patients with CLL with OKT8-positive cells was due to suppression or lack of help, the number of OKT4-positive cells was held constant, and OKT8-positive cells were added in increasing numbers. No suppression of colony formation could be demonstrated. Furthermore, the addition of increasing numbers of concanavalin A (Con A)-activated OKT8-positive cells did not suppress colony formation. These results suggest that the CLL T cell subsets behave in a functionally similar manner to normal T cell subsets, namely, (1) that normal and CLL B cell colony growth is helped by OKT4 cells; and (2) in contrast to immunoglobulin secretion by B cells, neither normal nor CLL OKT8 cells, unstimulated or activated by Con A, suppress B cell colony growth. 相似文献
993.
1临床资料输尿管结石560(男324,女236)例,年龄16~68(平均38)岁.其中左侧输尿管246例,右侧输尿管268例,双侧输尿管46例,合并肾功能减退者28例,合并妊娠12例,孤肾合并输尿管结石5例,上段输尿管139例,中段输尿管154例,下段输尿管267例,合并输尿管狭窄68例,合并输尿管息肉156例,合并输尿管扩张及不同程度肾积水286例,36例有肾或输尿管切开取石史,196例行体外震波碎石效果不佳,其中16例形成石街.本组经X线诊断的阳性结石388例,经B超或静脉肾盂造影诊断的阴性结石148例,未发现结石经输尿管镜诊断的结石24例. 相似文献
994.
Leptin protects mice from starvation-induced lymphoid atrophy and increases thymic cellularity in ob/ob mice 总被引:22,自引:0,他引:22
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Jane K. Howard Graham M. Lord Giuseppe Matarese Silvia Vendetti Mohammad A. Ghatei Mary A. Ritter Robert I. Lechler Stephen R. Bloom 《The Journal of clinical investigation》1999,104(8):1051-1059
Thymic atrophy is a prominent feature of malnutrition. Forty-eight hours' starvation of normal mice reduced the total thymocyte count to 13% of that observed in freely fed controls, predominantly because of a diminution in the cortical CD4(+)CD8(+) thymocyte subpopulation. Prevention of the fasting-induced fall in the level of the adipocyte-derived hormone leptin by administering exogenous recombinant leptin protected mice from these starvation-induced thymic changes. The ob/ob mouse, which is unable to produce functional leptin because of a mutation in the obese gene, has impaired cellular immunity together with a marked reduction in the size and cellularity of the thymus. We found that ob/ob mice had a high level of thymocyte apoptosis resulting in a ratio of CD4(+)CD8(+) (cortical) to CD4(-)CD8(-) (precursor) thymocytes that was 4-fold lower than that observed in wild-type mice. Peripheral administration of recombinant leptin to ob/ob mice reduced thymocyte apoptosis and substantially increased both thymic cellularity and the CD4(+)CD8(+)/CD4(-)CD8(-) ratio. In contrast, a comparable weight loss in pair-fed PBS-treated ob/ob mice had no impact on thymocyte number. In vitro, leptin protected thymocytes from dexamethasone-induced apoptosis. These data indicate that reduced circulating leptin concentrations are pivotal in the pathogenesis of starvation-induced lymphoid atrophy. 相似文献
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Jaap CA Trappenburg Irene Touwen Gerdien H de Weert-van Oene Jean Bourbeau Evelyn M Monninkhof Theo JM Verheij Jan-Willem J Lammers Augustinus JP Schrijvers 《Health and quality of life outcomes》2010,8(1):102
Background
Early treatment of COPD exacerbations has shown to be important. Despite a non-negligible negative impact on health related quality of life, a large proportion of these episodes is not reported (no change in treatment). Little is known whether (low burden) strategies are able to capture these unreported exacerbations. 相似文献998.
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