Niwano Y, Becker B A, Mitra R, Caldwell C W, Abdalla E B, Johnson H D
University of Missouri-Columbia, Dairy Science Department 65211.
Dev Comp Immunol. 1990 Winter;14(1):139-49. doi: 10.1016/0145-305x(90)90016-8.
Phytohemagglutinin (PHA) and concanavalin A (Con A)-induced blastogenesis of peripheral blood lymphocytes was examined in heat-stressed pre- and postpartal sheep. The peak responses of lymphocytes to PHA and Con A in heat-stressed sheep revealed significant reduction before and after parturition compared with those in the corresponding control animals kept under thermoneutral conditions. Furthermore, the effect of serum from control or heat-stressed sheep on PHA-induced lymphocyte blastogenesis was examined. Supplementation of serum from heat-stressed sheep significantly suppressed the blastogenesis of lymphocytes obtained from healthy sheep, bovine, and human donors. Unlike dexamethasone, heat-stressed sheep serum did not inhibit IL-2 production by PHA-stimulated human peripheral blood lymphocytes. These results indicate that the immunosuppression of heat-stressed sheep is in part mediated by serum factor(s) that can modulate T-cell function in a species nonspecific manner.
对热应激的产前和产后绵羊外周血淋巴细胞的植物血凝素（PHA）和刀豆球蛋白A（Con A）诱导的细胞增殖进行了检测。与处于热中性条件下的相应对照动物相比，热应激绵羊的淋巴细胞对PHA和Con A的峰值反应在分娩前后均显著降低。此外，还检测了来自对照或热应激绵羊的血清对PHA诱导的淋巴细胞增殖的影响。补充热应激绵羊的血清显著抑制了从健康绵羊、牛和人类供体获得的淋巴细胞的增殖。与地塞米松不同，热应激绵羊血清不抑制PHA刺激的人外周血淋巴细胞产生白细胞介素-2。这些结果表明，热应激绵羊的免疫抑制部分是由血清因子介导的，这些因子可以以种属非特异性方式调节T细胞功能。
