Tamura H, Kuzuhara H, Takeuchi T, Yamamoto H
Department of Immunology, National Institute of Neuroscience, Tokyo, Japan.
J Immunol. 1994 Feb 1;152(3):1134-40.
We previously reported that the nude mouse-derived splenic T cell clone N-9F exhibits a proliferative response when cultured on thymic stromal cells. This N-9F proliferation is mediated by direct cell-to-cell interactions between T and thymic stromal cells. A thymic epithelial cell clone, SL10.3, also supports N-9F growth. To identify the molecule involved in T cell development in the thymus, we established mAb specific to the N-9F clone. One of these mAb, QR6.6, was found to inhibit the N-9F proliferative response on SL10.3. QR6.6-positive cells were detected in thymus but not in other lymphoid organs such as bone marrow, lymph nodes, or spleen. QR6.6-positive cells accounted for 3 to 5% of the cells in adult thymuses whereas higher percentages were found in neonatal (10-20%) and fetal thymuses (70% at E17 and 10-20% at E15). The positive cells were primarily CD4-8- thymocytes in fetuses and CD4-8- to CD4+8+ thymocytes in adults. The QR6.6 mAb precipitates a 100 kDa molecule from the N-9F clone. The addition of the mAb to fetal thymus organ culture reduces the recovery of cells at culture day 4. It was also found that the mAb inhibits fetal thymocyte proliferation on the SL10.3 thymic epithelial cell line. These results suggest that the 100 kDa molecule detected by the QR6.6 mAb may play a crucial role in the early stage of thymocyte development.
我们先前报道，源自裸鼠的脾T细胞克隆N-9F在胸腺基质细胞上培养时会表现出增殖反应。这种N-9F增殖是由T细胞与胸腺基质细胞之间直接的细胞间相互作用介导的。一个胸腺上皮细胞克隆SL10.3也支持N-9F生长。为了鉴定参与胸腺中T细胞发育的分子，我们制备了针对N-9F克隆的单克隆抗体。其中一种单克隆抗体QR6.6被发现可抑制N-9F在SL10.3上的增殖反应。在胸腺中检测到QR6.6阳性细胞，但在其他淋巴器官如骨髓、淋巴结或脾脏中未检测到。QR6.6阳性细胞在成年胸腺细胞中占3%至5%，而在新生胸腺（10%-20%）和胎儿胸腺（E17时为70%，E15时为10%-20%）中所占比例更高。胎儿中的阳性细胞主要是CD4-8-胸腺细胞，而成人中是CD4-8-至CD4+8+胸腺细胞。QR6.6单克隆抗体从N-9F克隆中沉淀出一个100 kDa的分子。将该单克隆抗体添加到胎儿胸腺器官培养物中会降低培养第4天时细胞的回收率。还发现该单克隆抗体可抑制SL10.3胸腺上皮细胞系上的胎儿胸腺细胞增殖。这些结果表明，QR6.6单克隆抗体检测到的100 kDa分子可能在胸腺细胞发育的早期阶段起关键作用。
