Frequency of T-Cell Progenitors in Nude Mice

The hypothesis that prothymocytes are distinct from and regulated independently of multilineage hemopoietic progenitors was tested by enumeration of these two cell populations in normal versus congenitally athymic (nude) mice. The absence of a thymus and of peripheral T cells in nude mice had no effect on the frequency of either multilineage progenitors (day 12 CFU-S) or prothymocytes (CFU-T), suggesting that there is no feedback regulation of CFU-T frequency. Thymus seeding from the bone marrow is therefore likely to be regulated by the availability of niches for prothymocyte maturation, rather than by feedback control of prothymocyte production.     

Effects of topical anti-inflammatory drugs on eosinophil survival primed by epithelial cells. Additive effect of glucocorticoids and nedocromil sodium

Background Eosinophil infiltration is a hallmark of the inflammatory response in rhinitis and in nasal polypcsis. Objective We studied the effect of steroids and nedocromil sodium on eosinophil survival primed by epithelial cells from healthy (nasal mucosa) and inflamed (nasal polyp) respiratory tissue. Methods Blood eosinophils were incubated with increasing concentrations (10^-11 10^-5 M) of topical steroids (fiuticasone propionate, budesonide, triamcinolone acetonide and beclomethasone dipropionate) and/or nedocromil sodium prior to the addition of human epithelial cell conditioned media (HECM), eosinophil viability was measured and IC₅₀ for each drug was calculated. Results All four steroids and nedocromil sodium caused a dose-related inhibition of HECM-induced eosinophil survival. The IC₅₀ of steroids were lower in eosinophils primed by mucosa HECM than on those primed by polyp HECM (fluticasone, 4nM vs 114nM: budesonide, 21 nM vs 280 nM; triamcinolone, 7 nM vs 853 nM; and beclomethasone, 171 nM vs 181 nM). The combined inhibitory effect of 10^-7M budesonide plus 10^-5M nedocromil (43.8 ± 10.8%, P < 0.03) was significantly higher than budesonide (28.5 ± 9.2%) or nedocromil (16.7 ± 5.4%) alone and close to 10^-5M budesonide (52.3 ± 11%). No differences were found in cytokine (IL-8, IL-6, GM-CSF, TNFα, IL-lβ and RANTES) concentrations between HECM from mucosa and polyps. Conclusion These results suggest that topical anti-inflammatory drugs may diminish airway eosinophilic infiltration by decreasing eosinophil viability, that nasal polyp epithelial cell secretions may induce steroid resistance in eosinophils, and that nedocromil sodium has additive effects with steroids.     

Immunoelectron microscopic studies on centromere-kinetochore complexes detached from chromosomes

The centromere-kinetochore complexes of Chinese hamster ovary (CHO) cells were detached and separated from the condensed chromatin by treatment with hydroxyurea and caffeine. By labelling the complex for immunoelectron microscopy (immuno-EM) with a mixture of antibodies against centromere proteins (anti-CENP-A,-B, -C) in some cells, we could demonstrate complete detachment of the complexes. No remnants were left at the bulk of condensed chromatin in these cells. In some mitotic cells complex and chromatin were found side by side. It could be shown that the fine structure of the separated material of the complex differs significantly from that of the rest of chromatin. The complex consists of proteins and DNA. This leads us to suppose that the organization of chromatin in the centromere-kinetochore complex is different.     

Comparison of the use of bulk to micro culture of cell preparations for lymphokine-activated cytotoxicity assays.

Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells.     

白细胞介素-10诱导的大鼠树突状细胞体外免疫功能的研究

目的　研究白细胞介素 10 (IL 10 )诱导的大鼠未成熟树突状细胞 (imDCs)体外诱导免疫耐受的可行性。方法　在经典诱导方案的基础上 ,应用IL 10 ( 10 μg/L)抑制大鼠骨髓来源DCs的成熟 (IL 10组 ,10例 ) ,并设对照组 (IL 4组 ,10例 )。培养期间观察DCs形态 ,检测DCs表型、摄取抗原能力、体外免疫功能及培养上清细胞因子水平。结果　与IL 4组比较 ,IL 10组DCs细胞表面CD80 、CD86及OX6低度表达 ( 2 5 .3 %、42 .4%、3 2 .3 % ) ,吞噬能力较强 ( 81.9) ,刺激同种异体淋巴细胞增殖能力下降 ,该淋巴细胞具有抗原特异性低反应性 ;培养上清中IL 12水平 ( 4 0 6.5pg/L)及初次MLR培养上清IL 2水平 ( 2 45 .4ng/L)均较低 ,差异有非常显著性 (P <0 .0 1)。 结论　IL 10作用的大鼠imDCs具有诱导免疫耐受的应用价值。     

胎肝细胞输注对癌症病人化疗中外周血白细胞变化干预的序贯试验研究

本文自１９９１年１月以来．进行了静脉输注胎肝细胞悬液干扰化疗药物降白副反应的医学序贯试验。实验组病人静脉输注４～６月胎龄胎肝细胞悬液１６００～４０００ｍｌ（浓度５～７×１０９个／Ｌ），对照组按常规方法升白。通过２８例病人的序贯试验发现化疗期间输注胎肝细胞悬液的病人骨髓抑制发生延迟，持续时间短，程度减轻，从而为化疗正常进行提供基本条件。结论；胎肝细胞悬液输注可干扰化疗药物降白副反应的发生。     

病理性损伤因素对肾小管上皮细胞表型转化的影响

目的 :观察低血清、高糖、高蛋白刺激下肾小管上皮细胞向间叶性细胞的表型转化 ,探讨损伤的肾小管上皮细胞在肾小管间质纤维化中的作用。方法 :以体外培养的人近端肾小管上皮细胞为对象 ,分别用含低血清(0 .2mol·L-1小牛血清 )、高葡萄糖 (4.5 g·L-1)、高白蛋白 (15 g·L-1)的培养液培养 7d ,透射电镜检测细胞形态变化 ;免疫组化和Westernblot检测细胞表型改变 ,包括CK、Vimentin、α SMA、Ⅰ和Ⅲ型胶原 ,原位杂交检测Ⅰ型胶原mRNA表达 ,同时检测细胞TGFβ1蛋白表达。 结果 :低血清、高糖、高蛋白直接刺激下 ,肾小管上皮细胞出现明显形态学改变 ,包括细胞变为长梭形 ;透射电镜下细胞内线粒体明显减少 ,粗面内质网明显增加 ,并出现actin样微丝。免疫组化染色和Westernblot显示CK表达明显减弱 ,Vimentin、Ⅰ、Ⅲ型胶原、α SMA和TGFβ1表达增强。原位杂交显示Ⅰ型胶原mRNA表达增强。结论 :低血清、高糖、高蛋白可直接引起人近端肾小管上皮细胞TGFβ1表达增加 ,并发生向间叶性细胞的表型转化     

人骨髓间充质干细胞体外分化为雪旺样细胞的方法

目的 :建立人骨髓间充质干细胞体外向雪旺样细胞定向诱导分化的方法。方法 :取健康人骨髓血标本 ,利用percoll(密度为 1.0 73 g·ml-1)分离骨髓单个核细胞 ,在DMEM LG + 10 % (体积分数 )FBS中培养 ,通过流式细胞术对培养细胞进行表型测定 ,对第 2、3、5、8代间充质干细胞进行定向诱导分化 ,用单抗S 10 0、神经胶质纤维酸性蛋白 (glialfibrillargacidicprotein ,GFAP) ,通过免疫组化方法对诱导的细胞进行鉴定。 结果 :经 percoll分离的间充质干细胞可传 16代 ,细胞数增加了大约 6× 10 7倍。流式细胞术结果显示 :percoll分离出来的未经培养的细胞 ,其CD2 9+CD4 4 +CD3 4 -CD4 5 -细胞数为 3 2 .4 7%± 3 .4 9% ,而培养后贴壁细胞中CD2 9+CD4 4 +CD3 4 -CD4 5 -细胞数为 94 .3 8%± 1.5 0 %。诱导后免疫组化染色结果显示 :由 β ME +bFGF预诱导、β ME +bFGF诱导的S 10 0阳性细胞最多 ,可达 90 %± 4 % ,GFAP阳性细胞为 2 1%± 5 %。结论 :人骨髓中间充质干细胞能定向诱导分化成雪旺样细胞。     

Experimental Studyon Anti－tumor Effect of SplenocytesInduced by Anti－CD3McAb，PHA and IL－2

（沈张悦）（邵静芳）（王晓林）（朱慧芬）ＥｘｐｅｒｉｍｅｎｔａｌＳｔｕｄｙｏｎＡｎｔｉ－ｔｕｍｏｒＥｆｆｅｃｔｏｆＳｐｌｅｎｏｃｙｔｅｓＩｎｄｕｃｅｄｂｙＡｎｔｉ－ＣＤ３ＭｃＡｂ，ＰＨＡａｎｄＩＬ－２￥ＳＨＥＮＧｕａｎ－ｘｉｎ，ＷＡＮＧＸｉａｏ－ｌｉ...