Pike B L, Vaux D L, Nossal G J
J Immunol. 1983 Aug;131(2):554-60.
Three separate forms of in vitro stimulation were assessed for their capacity to activate hapten-gelatin fractionated, fluorescein- (Flu) specific murine splenic B lymphocytes. They were: a) Flu-polymerized flagellin (Flu-POL) acting on a single Flu-specific B cell in microculture in the absence of "filler" or feeder cells, but in the presence of T cell-derived B cell growth and differentiation factor(s) (BGDF); b) a mixture of mitogens, E. coli lipopolysaccharide (LPS) and dextran sulfate, acting on a single Flu-specific B cell in the absence of added BGDF; and c) Flu-POL plus BGDF acting on single Flu-specific B cells as in a but with thymus filler cells also present. System c was markedly superior in causing antibody formation, 15 to 22% of cells forming a clone of Flu-specific antibody-forming cells (AFC), in contrast to 6% for system b and 3 to 6% for system a. Each stimulus was applied to single cells that had been size fractionated into samples of increasing size by using the forward light-scattering parameter of the fluorescence-activated cell sorter. Surprisingly, the smaller sized fractions proliferated poorly in system a and contributed less than 10% of the antibody-forming potential of the total population. The smaller cells proliferated better in system b, but only 10 to 15% of proliferating clones generated Flu-specific AFC, whereas the larger cells contributed 86% of the total AFC response. Even in system c, only 6% of the small cells formed AFC clones compared with 41% of the larger cells. It thus appears that the smaller half of murine B lymphocytes is relatively resistant to activation into proliferation and differentiation by "T-independent" antigens; when activated by mitogens, they clone less efficiently than larger cells. Despite these limitations, system c could generate a total of up to four hapten-specific AFC for every B cell placed into culture, making it the most efficient system of specific antibody formation yet described.
评估了三种不同形式的体外刺激激活经半抗原 - 明胶分级分离的、针对荧光素（Flu）的特异性小鼠脾脏B淋巴细胞的能力。它们分别是：a）在微量培养中，荧光素聚合鞭毛蛋白（Flu - POL）作用于单个荧光素特异性B细胞，不存在“填充剂”或饲养细胞，但存在T细胞衍生的B细胞生长和分化因子（BGDF）；b）有丝分裂原混合物，即大肠杆菌脂多糖（LPS）和硫酸葡聚糖，在不添加BGDF的情况下作用于单个荧光素特异性B细胞；c）Flu - POL加BGDF作用于单个荧光素特异性B细胞，与a情况相同，但也存在胸腺填充细胞。系统c在引发抗体形成方面明显更优，15%至22%的细胞形成了荧光素特异性抗体形成细胞（AFC）克隆，相比之下，系统b为6%，系统a为3%至6%。每种刺激都应用于通过使用荧光激活细胞分选仪的前向光散射参数按大小分级为大小递增样本的单个细胞。令人惊讶的是，较小尺寸的级分在系统a中增殖不佳，其抗体形成潜力占总群体的比例不到10%。较小的细胞在系统b中增殖较好，但只有10%至15%的增殖克隆产生荧光素特异性AFC，而较大的细胞贡献了总AFC反应的86%。即使在系统c中，只有6%的小细胞形成AFC克隆，而较大细胞为41%。因此，似乎小鼠B淋巴细胞中较小的一半相对难以被“非T细胞依赖性”抗原激活而增殖和分化；当被有丝分裂原激活时，它们的克隆效率低于较大的细胞。尽管有这些局限性，系统c每培养一个B细胞最多可总共产生四个半抗原特异性AFC，使其成为迄今为止所描述的最有效的特异性抗体形成系统。
