Kruger M G, Riley R L, Riley E A, Elia J M
Department of Microbiology and Immunology, University of Miami School of Medicine, FL.
Blood. 1990 Jul 15;76(2):383-92.
Murine Ly1+ pre-B cell lines, including 70Z/3 and three pre-B cell lines derived from long-term bone marrow cultures, exhibited selective adherence to bone marrow stromal cells. In contrast, splenic B cells, the A20 B-cell lymphoma, and four Ly1- B cell lines derived from long-term bone marrow cultures failed to adhere substiantially to bone marrow cultures failed to adhere substiantially to bone marrow stroma. Ly1+ pre-B cell lines were induced to express kappa light chains by exposure to either lipopolysaccharide (LPS), recombinant interleukin-1 (IL-1), or stromal cells. However, induction of kappa light chains failed to prevent pre-B cell adherence to stromal cells. Supernatants derived from primary bone marrow stromal cells decreased Ly1 expression on the Ly1+ pre-B cell lines. These experiments suggest that (1) expression of immunoglobulin light chains by developing Ly1+ pre-B cells is mediated by bone marrow stromal cells; (2) loss of specific adherence to stroma is progressive and occurs post-light chain induction; and (3) soluble products of stromal cells may downregulate expression of surface Ly1 on otherwise Ly1+ pre-B cells. The importance of these observations to the development of both the Ly1- and Ly1+ B cell lineages in the mouse is discussed.
小鼠Ly1+前B细胞系，包括70Z/3和三个源自长期骨髓培养物的前B细胞系，表现出对骨髓基质细胞的选择性黏附。相比之下，脾B细胞、A20 B细胞淋巴瘤以及四个源自长期骨髓培养物的Ly1- B细胞系基本上未能黏附于骨髓基质。通过暴露于脂多糖（LPS）、重组白细胞介素-1（IL-1）或基质细胞，Ly1+前B细胞系被诱导表达κ轻链。然而，κ轻链的诱导未能阻止前B细胞黏附于基质细胞。源自原代骨髓基质细胞的上清液降低了Ly1+前B细胞系上Ly1的表达。这些实验表明：（1）发育中的Ly1+前B细胞免疫球蛋白轻链的表达由骨髓基质细胞介导；（2）对基质特异性黏附的丧失是渐进性的，且发生在轻链诱导之后；（3）基质细胞的可溶性产物可能下调原本Ly1+前B细胞表面Ly1的表达。本文讨论了这些观察结果对小鼠Ly1-和Ly1+ B细胞谱系发育的重要性。
