IL-2 expands and maintains IgM plasmablasts from a CD5+ subset contained within the germinal centre cell-enriched (surface IgD-/CD39- buoyant) fraction of human tonsil.
IL-2 expands and maintains IgM plasmablasts from a CD5+ subset contained within the germinal centre cell-enriched (surface IgD-/CD39- buoyant) fraction of human tonsil.
复制标题
IL-2 扩增并维持人扁桃体生发中心细胞富集（表面 IgD-/CD39- 浮力）部分中包含的 CD5 子集的 IgM 浆母细胞。
DOI：
10.1093/intimm/5.9.1059
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发表时间：
1993
影响因子：
4.4
通讯作者：
J. Gordon
中科院分区：
文献类型：
--
作者：
M. Holder;S. Abbot;A. Milner;C. Gregory;M. Casamayor;G. Johnson;I. Maclennan;J. Gordon
发现IL-2促进人扁桃体B淋巴细胞的生发中心（GC）细胞富集（CD 39-和/或IgD-漂浮）部分内所含的少数群体的快速生长。出现的细胞响应IL-2有较高的有丝分裂指数和形态类似浆母细胞。培养物可在不存在饲养细胞的情况下在IL-2中维持长达3周，并且其特征在于其上清液中含有大量IgM：到培养第10天，约40%的细胞含有易于检测的细胞质IgM。IL-2驱动的扩增和IgM分泌的目标群体为smIg+/CD 38+，并且受到抗IgM抗体的抑制。虽然在GC细胞富集级分中只有8%的细胞是CD 5+（与15%的高密度静息B细胞相比），但它们的去除导致响应于IL-2产生的IgM的量减少83%，IL-2选择性地扩增该次要的CD 5+亚群，使得到培养的第6天，它们包含所有活细胞的57%。建立与IL-2的培养物显示细胞质Bcl-2的表达增加和生长因子的撤回导致细胞死亡通过凋亡。我们讨论了这些结果与CD 5 + B细胞和它们在TD抗原的抗体应答中的潜在作用。
IL-2 was found to promote the rapid growth of a minority population contained within the germinal centre (GC) cell-enriched (CD39- and/or IgD- buoyant) fraction of human tonsillar B lymphocytes. The cells emerging in response to IL-2 had a high mitotic index and morphologically resembled plasmablasts. Cultures could be maintained in the absence of feeder cells for up to 3 weeks in IL-2 and were characterized by large amounts of IgM in their supernatants: approximately 40% of the cells contained readily detectable cytoplasmic IgM by day 10 of culture. Negligible quantities of IgG and IgA were found. The target population for IL-2-driven expansion and IgM secretion was smIg+/CD38+ and was subject to suppression by anti-IgM antibody. While only 8% of cells within the GC cell-enriched fraction were CD5+ (compared with 15% of high density resting B cells), their removal led to an 83% reduction in the amount of IgM produced in response to IL-2, IL2 selectively expanded this minor CD5+ subset such that by day 6 of culture they comprised 57% of all viable cells. Cultures established with IL-2 showed increasing expression of cytoplasmic Bcl-2 and withdrawal of growth factor resulted in cell death via apoptosis. We discuss these results in relation to CD5+ B cells and their potential role in antibody responses to TD antigens.