Smith P B, Turpen J B
Department of Anatomy, University of Nebraska Medical Center, Omaha 68198-6395.
Dev Immunol. 1991;1(4):295-307. doi: 10.1155/1991/60923.
The monoclonal antibody CL21 recognizes a determinant present on the surface of leukocytes, but not on erythrocytes or nonhemopoietic tissue. The CL21 antigen was first expressed at 48 hr of development at 20 degrees C (stage 28) on embryonic cells cultured from lateral plate mesoderm. Based on immunofluorescence staining and flow cytometric analysis, the distribution of fluorescence intensity of larval thymocytes and splenocytes was unimodal. Distributions of dull and bright cells were detected in both adult thymocytes and splenocytes. These different subpopulations appeared during the late perimetamorphic period. Adult splenocytes were metabolically activated when cultured in the presence of mAb CL21 bound to a substrate but not in the presence of mAb CL21 in suspension. Immunoprecipitation and SDS-PAGE under nonreducing conditions revealed that a single 180-kD molecule was expressed on thymocytes. Analysis of splenocytes demonstrated the presence of two molecules having similar molecular mass that resolved to a single band under reducing conditions.
单克隆抗体CL21识别白细胞表面存在的一种决定簇，但不识别红细胞或非造血组织表面的决定簇。CL21抗原在20摄氏度发育48小时（第28阶段）时首次在从侧板中胚层培养的胚胎细胞上表达。基于免疫荧光染色和流式细胞术分析，幼虫胸腺细胞和脾细胞的荧光强度分布是单峰的。在成年胸腺细胞和脾细胞中均检测到暗淡和明亮细胞的分布。这些不同的亚群出现在变态后期。当在与底物结合的单克隆抗体CL21存在下培养时，成年脾细胞会发生代谢激活，但在悬浮的单克隆抗体CL21存在下则不会。非还原条件下的免疫沉淀和SDS-PAGE显示，胸腺细胞上表达单一的180-kD分子。脾细胞分析表明存在两个分子量相似的分子，在还原条件下可解析为一条带。
