Seto A, Kumagai K
Department of Microbiology, Shiga University of Medical Science, Otsu, Japan.
Leuk Res. 1993 Jul;17(7):567-72. doi: 10.1016/0145-2126(93)90086-z.
The presence of a leukemogenesis-associated antigen was investigated in an experimental model of adult T-cell leukemia in (B/J x Chbb:HM)F1 rabbits, where adult rabbits develop leukemia within 1-2 weeks following inoculation with HTLV-I-transformed syngeneic cell lines. Leukemogenic activity was found in some but not all HTLV-I-transformed cell lines, and was associated with leukocytosis-inducing activity which was assayed by inoculating these cells into adult rabbits of the parental Chbb:HM strain. The leukemogenic cell line diminished or lost the leukemogenic and leukocytosis-inducing activities during prolonged culture in vitro. A mouse mAb was raised which recognized an antigen uniquely expressed on the cell surface of the leukemogenic cell lines. This antigen was present, however, in all HTLV-I-transformed cells examined and the mAb immunoprecipitated the same 65 kD glycoproteins from both leukemogenic and non-leukemogenic cell lines. Taken together, the antigenic epitope seemed to be expressed on the cell surface in such a manner as to be accessible to the mAb in leukemogenic but not non-leukemogenic cells. The analyses of various cell lines revealed that this antigen was an endogenous antigen and not a viral antigen. The antibody was cytotoxic in vitro against leukemogenic cell lines in the presence of complement, and administration of this antibody to leukemic rabbits resulted in an abrupt decrease in the peripheral blood leukocyte number, leading to remission of the disease.
在（B/J×Chbb:HM）F1 兔的成人 T 细胞白血病实验模型中，研究了白血病发生相关抗原的存在情况。在该模型中，成年兔接种 HTLV-I 转化的同基因细胞系后 1 - 2 周内会发生白血病。在部分但并非所有的 HTLV-I 转化细胞系中发现了致白血病活性，且其与白细胞增多诱导活性相关，后者通过将这些细胞接种到亲代 Chbb:HM 品系的成年兔中进行测定。致白血病细胞系在体外长期培养过程中，其致白血病和白细胞增多诱导活性会减弱或丧失。制备了一种小鼠单克隆抗体，该抗体识别在致白血病细胞系细胞表面独特表达的一种抗原。然而，在所检测的所有 HTLV-I 转化细胞中均存在这种抗原，并且该单克隆抗体从致白血病和非致白血病细胞系中免疫沉淀出相同的 65kD 糖蛋白。综合来看，该抗原表位似乎以一种在致白血病细胞而非非致白血病细胞中能被单克隆抗体识别的方式在细胞表面表达。对各种细胞系的分析表明，这种抗原是一种内源性抗原而非病毒抗原。该抗体在补体存在的情况下，体外对致白血病细胞系具有细胞毒性，给白血病兔注射这种抗体导致外周血白细胞数量急剧减少，从而使疾病缓解。
