Matsuo Y, Nakamura S, Ariyasu T, Terao R, Imajyo K, Tsubota T, Kuwahara K, Sakaguchi N
Fujisaki Cell Center, Hayashibara Biochemical Labs Inc, Okayama, Japan.
Leukemia. 1996 Apr;10(4):700-6.
A human acute lymphoblastic leukemia (ALL) cell line, BALM-9, was established from the peripheral blood specimen of a immunoglobin (lg) phenotype, the established BALM-9 cell line expressed both kappa and lambda light (L) chains simultaneously in a range of 30-80%. Two-color flow cytometric analysis demonstrated that there was a distinct population of kappa lambda double positive cells as well as kappa single, lambda single, and double negative populations. Therefore, subclones were obtained from each population by limiting dilution and were designated BALM-9KL (kappa+lambda+), BALM-9K (kappa+lambda-), BALM 9N (kappa-lambda-). Western blotting confirmed the results of the immunofluorescence test at the protein level. In BALM-9N, L chains were absent even in the cytoplasm as demonstrated by Western blotting. Evidence that the subclones have the same ancestry was provided both by cytogenetic analysis and by Southern blotting, which revealed the 14q32 chromosomal rearrangement as a common abnormality and the same IgH gene arrangement among the subclones. The existence of a kappa lambda positive B cell population suggests a transient stage of normal B cell maturation. These subclones might represent such a stage and thus provide a useful means of analyzing the mechanism of this double light chain expression.
一种人类急性淋巴细胞白血病（ALL）细胞系BALM-9，是从一名具有免疫球蛋白（Ig）表型的外周血标本中建立的。所建立的BALM-9细胞系同时表达κ和λ轻链（L链），表达率在30%至80%之间。双色流式细胞术分析表明，存在一个明显的κλ双阳性细胞群体以及κ单阳性、λ单阳性和双阴性群体。因此，通过有限稀释从每个群体中获得亚克隆，并分别命名为BALM-9KL（κ+λ+）、BALM-9K（κ+λ-）、BALM 9N（κ-λ-）。蛋白质印迹法在蛋白质水平上证实了免疫荧光试验的结果。在BALM-9N中，蛋白质印迹法显示即使在细胞质中也不存在L链。细胞遗传学分析和Southern印迹法均提供了证据，表明这些亚克隆具有相同的起源，这两种方法揭示14q32染色体重排是一种常见异常，且亚克隆之间具有相同的IgH基因排列。κλ阳性B细胞群体的存在提示正常B细胞成熟的一个过渡阶段。这些亚克隆可能代表这样一个阶段，从而为分析这种双轻链表达机制提供了一种有用的手段。
