Yano M, Kondo N, Kato Y, Shinoda S, Inoue R, Orii T
Department of Pediatrics, Gifu University School of Medicine, Japan.
Exp Clin Immunogenet. 1995;12(1):1-9.
VpreB and lambda-like genes encode proteins that can associate to form a light-chain-like structure, the surrogate light chain (SLC). VpreB and lambda-like genes are selectively expressed in human progenitor B and precursor B (pre-B) cells. We analyzed the expression of VpreB and lambda-like genes in seven patients with common variable immunodeficiency (CVI). Gene expression was examined in the peripheral blood mononuclear cells (PBMCs) using the polymerase chain reaction. In four CVI patients, two of whom were brothers, the expression of the VpreB gene was detectable in the PBMCs. In the brothers with CVI, the expression of the VpreB gene was also examined in bone marrow cells, where it was found to be expressed in trace amounts. A number of the brothers' bone marrow cells were stained with mu and kappa antibodies using the avidin-biotin complex method. In lambda 5-gene-deleted mice, B cell development in the bone marrow is blocked at the pre-B stage, but the blockade is leaky. We suggest that expression of the SLC is weak in patients with CVI compared with their normal counterparts, and this may be one of the underlying mechanisms of CVI.
VpreB基因和类λ基因编码的蛋白质可相互结合形成类似轻链的结构，即替代轻链（SLC）。VpreB基因和类λ基因在人类祖B细胞和前B细胞（pre - B细胞）中选择性表达。我们分析了7例常见变异型免疫缺陷病（CVI）患者中VpreB基因和类λ基因的表达情况。采用聚合酶链反应在外周血单个核细胞（PBMC）中检测基因表达。在4例CVI患者中，其中2例为兄弟，PBMC中可检测到VpreB基因的表达。在患CVI的兄弟中，还对骨髓细胞中的VpreB基因表达进行了检测，发现其表达量极少。采用抗生物素蛋白-生物素复合物法用μ和κ抗体对一些兄弟的骨髓细胞进行染色。在λ5基因缺失的小鼠中，骨髓中的B细胞发育在前B阶段受阻，但这种阻断并不完全。我们认为，与正常对照相比，CVI患者中SLC的表达较弱，这可能是CVI的潜在机制之一。
