CD4单克隆抗体改变新生小鼠胸腺细胞亚群的分布和功能

新生期小鼠（３～７天）腹腔注入ＣＤ４ＭｃＡｂ，可引起胸腺细胞表型和功能变化。胸腺细胞表型分析显示：胸腺细胞总数、ＤＰ和ＣＤ４ＳＰ细胞明显减少；ＣＤ８ＳＰ细胞数增加；ＤＮ细胞数目变化不大。上述变化与ＣＤ４ＭｅＡｂ和胸腺细胞表面的ＣＤ４分子的结合有关。功能试验表明：实验组小鼠胸腺细胞对有丝分裂素ＣｏｎＡ、ＰＷＭ的反应性降低，混合淋巴细胞反应（ＭＬＲ）也明显低于对照组。但是胸腺细胞对异型细胞的杀伤作用则高于对照组。功能试验的结果与表型的变化是吻合的，有剂量依赖性。ＣＤ４ＭｃＡｂ引起的胸腺细胞表型和功能的变化是可以恢复的，一般于注射ＣＤ４ＭｃＡｂ后１０天，胸腺细胞亚群分布恢复或接近正常，而功能则恢复较慢。

Effect of anti-CD4 McAb treatment of phenotype and function of mouse thymocyte

The phenotype and function of thymocytes were significantly affected in anti-CD4 McAb ( GK 1 . 5) treated (ip) neonatal mice (3- 7 days old ). Two-color analysis of CD4 and CD8 of thymocytes from the GK 1. 5 treated mice showed that the total number of thymocytes ,proportion and absolute number of DP ,CD4SPcells were obviously decreased , whereas ,CD8SP cells was increased. In contrast ,GK 1 . 5 had little effect on the absolute number of DN cells. Surprisingly , we found that the variation of phenotype in thymocytes might result from binding of anti-CD4 McAb. Thymocyte responsiveness to Con A , PWM and allogeneic antigen stimulation reduced remarkably in anti-CD4 McAb treated mice , but the cytotoxicity of CTL to allogeneic cells was enhanced. The changes in phenotype and function of thymocytes were in anti CD4-dose dependent manner and recovered gradually. The recovery time of thymocyte function was much longer than that of phenotype.