Lawler D F, Hopkins J, Watson E D
Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, Easter Bush Veterinary Centre, Midlothian, UK.
J Reprod Fertil. 1999 Nov;117(2):281-90. doi: 10.1530/jrf.0.1170281.
Recent evidence indicates that the cells of the immune system and their large network of secretory products, or cytokines, play an active role in the ovary throughout the oestrous cycle. In the present study, immune cell populations (T and B lymphocytes, macrophages, granulocytes and eosinophils) and expression of major histocompatibility complex (MHC) class II were investigated in corpora lutea from mares in early (days 2-4), mid- (days 7-10) and late (days 12-14) dioestrus, the post-luteolytic phase (days 16-17) and early pregnancy. The number of T lymphocytes within the corpus luteum increased in the late luteal phase. CD4+ cells did not increase until day 16, whereas the number of CD8+ cells increased before functional luteolysis; an apparently selective luteal infiltration of CD8+ cells was observed. MHC class II expression by non-steroidogenic cells was increased in samples from days 16-17, as was the number of infiltrating macrophages. Flow cytometry revealed very low expression of MHC class II by large luteal cells at all stages of the oestrous cycle. In early pregnancy, the number of CD4+ and CD8+ cells and macrophages decreased, as did MHC class II expression, compared with mid-dioestrous samples. B cells were present in very small numbers in all samples examined. Eosinophils were similarly sparsely distributed and numbers decreased further in pregnancy. After exogenous PGF2 alpha administration, populations of CD4+ cells and non-specific esterase staining cells were significantly smaller than after natural luteolysis, whereas eosinophil numbers were increased compared with samples from days 16-17. However, the number of CD8+ and CD5+ cells and MHC class II expression were not significantly different from those observed after natural luteolysis. These findings indicate that populations of immune cells in the equine corpus luteum vary during its lifespan. The selective increase in CD8+ cells before functional luteolysis indicates that they have a physiological role in the regression of the corpus luteum.
最近的证据表明，免疫系统细胞及其庞大的分泌产物网络（即细胞因子）在整个发情周期中对卵巢发挥着积极作用。在本研究中，对处于发情间期早期（第2 - 4天）、中期（第7 - 10天）和晚期（第12 - 14天）、黄体溶解后阶段（第16 - 17天）以及妊娠早期的母马黄体中的免疫细胞群体（T和B淋巴细胞、巨噬细胞、粒细胞和嗜酸性粒细胞）以及主要组织相容性复合体（MHC）II类的表达进行了研究。黄体期晚期黄体中的T淋巴细胞数量增加。CD4⁺细胞直到第16天才增加，而CD8⁺细胞数量在功能性黄体溶解前增加；观察到CD8⁺细胞明显选择性地浸润黄体。来自第16 - 17天样本中，非类固醇生成细胞的MHC II类表达增加，浸润的巨噬细胞数量也增加。流式细胞术显示，在发情周期的所有阶段，大黄体细胞的MHC II类表达都非常低。与发情间期中期样本相比，妊娠早期CD4⁺和CD8⁺细胞以及巨噬细胞的数量减少，MHC II类表达也减少。在所检查的所有样本中，B细胞数量极少。嗜酸性粒细胞分布同样稀少，妊娠时数量进一步减少。外源性给予前列腺素F2α后，CD4⁺细胞群体和非特异性酯酶染色细胞显著少于自然黄体溶解后的情况，而与第16 - 17天样本相比，嗜酸性粒细胞数量增加。然而，CD8⁺和CD5⁺细胞数量以及MHC II类表达与自然黄体溶解后观察到的情况无显著差异。这些发现表明，马黄体中的免疫细胞群体在其生命周期中有所变化。功能性黄体溶解前CD8⁺细胞的选择性增加表明它们在黄体退化中具有生理作用。
