Nair C N, Gothoskar B P, Gladstone B, Badrinath Y, Chhajlani V, Karnik M, Nerurkar A, Damle S R, Redkar S L, Gopal R
Neoplasma. 1987;34(3):305-11.
TdT (terminal deoxynucleotidyl transferase) can be detected by radio enzymatic assay, biochemical assay in cell extracts, serum or plasma, and intracellularly in the smear by indirect immunofluorescent methods. The IgG fraction of anti-TdT serum is conjugated with fluoresceinisothiocyanate and used directly on the cytospin smears of methanol fixed bone marrow/blood smears. The mice thymocytes and peripheral mononuclear cells of healthy donors were used as positive and negative controls, respectively, for TdT. 64% of our cases of ALL were found to be TdT+. The lymphoblasts of L1 morphology (FAB classification) were more frequently positive for TdT as compared to blasts with L2 morphology. 71% of our cALLa positive blasts in acute lymphoblastic leukemias were TdT+ve as compared to 58% of T-ALL blasts. 75% of PAS positive ALL cases were positive for TdT as well. Only 57% of the cases when acid phosphatase showed unipolar positivity (T type) were positive for TdT. 12% of cases with acute myeloid leukemia (6/47) were TdT+ve and 33% of CML in blastic crisis had TdT+ve blasts. Biochemical assay and IF assay for TdT were in good correlation in our study.
末端脱氧核苷酸转移酶（TdT）可通过放射酶法、细胞提取物、血清或血浆中的生化检测以及间接免疫荧光法在涂片细胞内进行检测。抗TdT血清的IgG组分与异硫氰酸荧光素结合，直接用于甲醇固定的骨髓/血液涂片的细胞离心涂片。健康供体的小鼠胸腺细胞和外周血单个核细胞分别用作TdT的阳性和阴性对照。我们发现64%的急性淋巴细胞白血病（ALL）病例TdT呈阳性。与L2形态的原始细胞相比，L1形态（FAB分类）的原始淋巴细胞TdT阳性更为常见。在急性淋巴细胞白血病中，我们的普通型急性淋巴细胞白血病抗原（cALLa）阳性原始细胞中有71%TdT呈阳性，而T细胞急性淋巴细胞白血病（T-ALL）原始细胞中这一比例为58%。75%的过碘酸雪夫反应（PAS）阳性ALL病例TdT也呈阳性。酸性磷酸酶呈单极阳性（T型）的病例中，只有57%的病例TdT呈阳性。12%的急性髓系白血病病例（6/47）TdT呈阳性，33%的慢性粒细胞白血病急变期病例有TdT阳性的原始细胞。在我们的研究中，TdT的生化检测和免疫荧光检测结果具有良好的相关性。
