Mulligan S P, Dao L P, Francis S E, Thomas M E, Gibson J, Cole-Sinclair M F, Wolf M
Department of Haematology, Concord Hospital, Sydney, Australia.
Br J Haematol. 1998 Oct;103(1):157-62. doi: 10.1046/j.1365-2141.1998.00928.x.
We report 10 cases of B-cell chronic lymphocytic leukaemia (B-CLL) with expression of the T-cell antigen CD8. The majority of patients had typical B-cell CLL with stable and non-progressive stage A(O) disease except for more common expression of lambda light chain and CD25. Two patients had progressive disease and required therapy, one with atypical morphological and phenotypic features. The incidence of CD8 expression was approximately 0.5% of B-CLL patients from our institutions. Immunoprecipitation of the CD8 antigen from four of these B-CLLs showed identity to the CD8 antigen expressed on T cells with precipitation of CD8alpha bands of molecular weight approximately 34 kD. In view of the known intracellular signalling mechanism of CD8 using the tyrosine kinase p56-lck, we studied p56-lck expression by Western blot and found lack of consistent expression of the CD8 surface antigen, with most lacking p56-lck. Our report indicates that CD8 expression in B-CLL is probably underrecognized but is not a marker of disease progression. The CD8 on the B-CLL surface is immunochemically identical to the antigen on T cells, but is not accompanied by its usual signalling mechanism of p56-lck tyrosine kinase and therefore is unlikely to be a functionally active receptor.
我们报告了10例表达T细胞抗原CD8的B细胞慢性淋巴细胞白血病（B-CLL）。除λ轻链和CD25表达更为常见外，大多数患者患有典型的B细胞CLL，处于稳定且非进展性的A（O）期疾病。两名患者患有进展性疾病，需要进行治疗，其中一名具有非典型的形态学和表型特征。在我们机构的B-CLL患者中，CD8表达的发生率约为0.5%。对其中4例B-CLL的CD8抗原进行免疫沉淀，结果显示与T细胞上表达的CD8抗原相同，沉淀出分子量约为34 kD的CD8α条带。鉴于已知CD8利用酪氨酸激酶p56-lck的细胞内信号传导机制，我们通过蛋白质印迹法研究了p56-lck的表达，发现CD8表面抗原缺乏一致的表达，大多数缺乏p56-lck。我们的报告表明，B-CLL中的CD8表达可能未得到充分认识，但不是疾病进展的标志物。B-CLL表面的CD8在免疫化学上与T细胞上的抗原相同，但不伴有其通常的p56-lck酪氨酸激酶信号传导机制，因此不太可能是具有功能活性的受体。
