Amano M, Baumgarth N, Dick M D, Brossay L, Kronenberg M, Herzenberg L A, Strober S
Department of Medicine, Stanford University School of Medicine, CA 94305-5111, USA.
J Immunol. 1998 Aug 15;161(4):1710-7.
We have used multicolor FACS analysis, immunohistology, and functional assays to study the expression of CD1 on B cell subsets from normal and beta 2m-/- mice. Two B cell subpopulations were identified that express high levels of CD1 in normal mice: splenic marginal zone B cells (IgMhigh IgDlow CD21high CD24intermediate CD23- CD43-) and a newly identified subpopulation of follicular B cells. The latter cells are unusual, because they are IgDhigh CD23+, like follicular B cells, but express high levels of CD21 and IgM, an expression pattern that is associated with marginal zone B cells. Therefore, the high-level expression of CD1 and CD21 was found to be closely associated on splenic B cells. Immunohistology confirmed the expression of CD1 on marginal zone B cells and on clusters of B cells in splenic follicles. Both the high-level CD1 expression by these cells and the low-level CD1 expression by subpopulations of B cells in the spleen, lymph node, peritoneal cavity, and bone marrow were markedly reduced in beta 2m-/- mice. Despite this, a CD1-restricted T cell clone proliferated vigorously in response to LPS-activated spleen cells that had been obtained from both beta 2m-/- and wild-type mice. This response was inhibited by the 3C11 anti-CD1 mAb. These results show the heterogeneity of B cell subsets in their expression of the beta 2m-dependent form of CD1. They further suggest that a beta 2m-independent form of CD1 is expressed on B cells that can stimulate T cells; however, this form is not easily visualized with the anti-CD1 mAb used here.
我们运用多色荧光激活细胞分选术（FACS）分析、免疫组织学和功能测定法，研究了正常小鼠和β2m基因敲除小鼠B细胞亚群中CD1的表达情况。在正常小鼠中，鉴定出两个高表达CD1的B细胞亚群：脾脏边缘区B细胞（IgM高IgD低CD21高CD24中等CD23-CD43-）和一个新鉴定出的滤泡B细胞亚群。后一种细胞不同寻常，因为它们像滤泡B细胞一样IgD高CD23+，但却高表达CD21和IgM，这种表达模式与边缘区B细胞相关。因此，发现脾脏B细胞上CD1和CD21的高表达密切相关。免疫组织学证实了边缘区B细胞以及脾脏滤泡中B细胞簇上CD1的表达。在β2m基因敲除小鼠中，这些细胞的CD1高表达以及脾脏、淋巴结、腹腔和骨髓中B细胞亚群的CD1低表达均明显降低。尽管如此，一个CD1限制性T细胞克隆对来自β2m基因敲除小鼠和野生型小鼠的经脂多糖（LPS）激活的脾细胞有强烈增殖反应。这种反应被3C11抗CD1单克隆抗体抑制。这些结果显示了B细胞亚群在β2m依赖形式的CD1表达上的异质性。它们进一步表明，一种β2m非依赖形式的CD1在能刺激T细胞的B细胞上表达；然而，用此处使用的抗CD1单克隆抗体不易观察到这种形式。
