Chadburn A, Inghirami G, Knowles D M
Department of Pathology Columbia University College of Physicians and Surgeons, New York, NY 10032.
Am J Pathol. 1990 Jan;136(1):29-37.
LeuM5 antigen (CD11c, p150.95) expression, widely used as an immunodiagnostic marker for B-cell hairy cell leukemia, was examined on benign, normal peripheral blood T cells before and after stimulation in vitro with phytohemagglutinin and on a large, diverse panel of 73 T-cell neoplasms. Resting T cells lacked LeuM5. Intracytoplasmic LeuM5 was detectable at 3 to 4 days and surface membrane LeuM5 was detectable continuously between 5 and 17 days on greater than or equal to 20% CD3 cells (maximum, 42% CD3 cells at 10 days) after activation. Two-color flow cytometric analysis of the activated T cells demonstrated that a maximum of 60% CD8 but only 25% CD4 cells expressed LeuM5; the mean percentage of LeuM5+ CD8 cells was 44% compared with 12% LeuM5+ CD4 cells. A variable proportion of the neoplastic T cells in 19 of 73 (26%) T-cell neoplasms were LeuM5+. Twelve of 18 CD4-CD8+ (67%) but only 5 of 40 CD4+ CD8- T-cell neoplasms expressed LeuM5. These studies demonstrate that the LeuM5 antigen is 1) expressed in association with T-cell activation, 2) preferentially expressed by activated CD8 cells, and 3) variably expressed by neoplastic T cells, but particularly by those exhibiting the CD4- CD8+ phenotype.
作为B细胞毛细胞白血病免疫诊断标志物广泛应用的LeuM5抗原（CD11c，p150.95），在体外经植物血凝素刺激前后的良性、正常外周血T细胞以及73种不同类型的T细胞肿瘤上进行了检测。静息T细胞缺乏LeuM5。激活后，在大于或等于20%的CD3细胞上（最多在第10天为42%的CD3细胞），胞质内LeuM5在3至4天可检测到，细胞膜表面LeuM5在5至17天持续可检测到。对激活的T细胞进行双色流式细胞术分析显示，最多60%的CD8细胞但仅25%的CD4细胞表达LeuM5；LeuM5+ CD8细胞的平均百分比为44%，而LeuM5+ CD4细胞为12%。在73种T细胞肿瘤中的19种（26%）中，不同比例的肿瘤性T细胞为LeuM5+。18种CD4-CD8+肿瘤中的12种（67%）但40种CD4+ CD8- T细胞肿瘤中仅5种表达LeuM5。这些研究表明，LeuM5抗原1）与T细胞激活相关表达，2）优先由激活的CD8细胞表达，3）在肿瘤性T细胞中表达可变，但尤其在表现出CD4- CD8+表型的细胞中表达。
