鸡盲肠扁桃体中B淋巴细胞的发育

Development of B lymphocytes in caecal tonsil of chicken

通过免疫组织化学方法,应用IgMI、gG和IgA单克隆抗体研究了IgM＋I、gG＋和IgA＋B淋巴细胞在鸡盲肠扁桃体中的出现、迁移、组织定位分布以及数量变化规律等一系列发育过程。结果显示,IgM＋细胞在胚胎20日龄时开始出现,而IgG＋和IgA＋细胞均在雏鸡出壳后1日龄时出现。在定位分布变化上,4日龄之前,B淋巴细胞主要分布在黏膜上皮下固有层中;4~7日龄时,B淋巴细胞则主要分布在黏膜固有层的中上部区域,随后各日龄B淋巴细胞均匀地分布在黏膜固有层中;14日龄时,黏膜固有层中出现主要由B淋巴细胞组成的生发中心,21日龄时可见轮廓更清晰的生发中心存在于黏膜固有层中下部区域,并且生发中心中存在大量的IgM＋I、gG＋和IgA＋细胞。在数量变化上,B淋巴细胞随着日龄增长数量持续增加,直至35日龄时趋于稳定,各日龄的B淋巴细胞数量始终以IgM＋细胞最多,IgA＋细胞次之,IgG＋细胞最少。证实,鸡出壳后初期盲肠扁桃体的体液免疫功能逐渐增强,并在35日龄时达到成熟水平。

The occurrence,migration,tissue localization and quantity changes of IgM＋,IgG＋ and IgA＋ B lymphocytes in chicken caecal tonsil were examined using the IgM,IgG and IgA monoclonal antibodies by immunohistochemical method.The results showed that IgM＋ cells first appeared in caecal tonsil from embryonic on day 20,both IgG＋ and IgA＋ cells appeared at 1-day-old.B lymphocytes mainly distributed in lamina propria under epithelium before 4-day-old;B lymphocytes were mainly distributed in middle and superior part mucous layer,whereafter they uniformly distributed in the whole mucous layer.The germinal centers which were composed by B lymphocytes appeared in the lamina propria at 14-day-old,but clear-cut germinal centers resided in the middle and inferior part of lamina propria at 21-day-old,and there were numerous IgM＋,IgG＋ and IgA＋ cells in germinal centers.B lymphocytes kept increasing with the increase of age,and reached stable at 35-day-old.Among the three type cells,IgM＋ cells were the most and IgG＋ cells were the least all the time.The results confirmed that the humoral immune function of caecal tonsil in chicken strengthened quickly after hatching,and reached the mature level at 35-day-old.