REDUCTION OF IMMUNE MEMORY IN SPECIFIC IMMUNITY TO RHODOCOCCUS EQUI IN MICE MODEL

在小鼠中，用活的毒力强的马雷氏杆菌免疫可以保护小鼠免受毒力生物的侵害，而热杀灭的毒力强的或活的毒力强的细菌则没有保护作用。在亚致死接种ATCC 33701后第5天观察到保护性免疫，在攻毒前9天启动的小鼠对攻毒菌的清除效果最好。在几周的时间里，活的毒力强的马马驹的免疫记忆下降了。本研究的目的是阐明小鼠模型中相同雷氏杆菌特异性免疫记忆降低的机制。为了检测免疫脾脏细胞中IFN-γ和TNF-α的产生，小鼠分别免疫7、17、21和28天。免疫7 d的小鼠免疫后脾脏细胞IFN-γ和TNF- a的分泌量最高，免疫17 d后脾脏细胞的分泌量与正常小鼠相当。将免疫7天或14天的小鼠的更多的en细胞转移到正常小鼠身上，并用毒力强的马氏雷氏杆菌攻击小鼠。脾细胞诱导小鼠转移免疫7 d有效，14 d无效。分别用抗il - 10单克隆抗体免疫7天和21天的小鼠，再用毒力强的马芮氏菌攻毒。与未处理免疫小鼠相比，抗il -10抗体对脏器中马氏弓形虫的清除无影响。另一方面，体外抗IL-10单克隆抗体实验表明，IL-10对免疫脾细胞产生IFN-γ和TNF-α具有有效的作用。用抗CD44、CD62L和CD45RB抗体流式细胞术分析脾脏细胞上CD44、CD62L和CD45RB抗原的表达。然而，免疫小鼠的脾脏T细胞在7天和21天之间没有变化。综上所述，IL-10可能在马蹄马感染小鼠免疫记忆的建立和降低中发挥关键作用，但马蹄马感染对T细胞失活或耐受的机制尚不清楚。少

Immunization with live virulent R. equi conferred protection against virulent organisms in mice, whereas heat-killed virulent or live avirulent bacteria offered no protection. The protective immunity was observed 5 days after the sublethal inoculation with live ATCC 33701, and the most effective clearance of challenged bacteria was found in the mice primed at 9 days before the challenge. Immune memory by the live virulent R. equi reduced for a few weeks. The purpose of this study is to elucidate the mechanism of the reduction of R. equi-specific immune memory in mice model. To measure the production of IFN-γ and TNF-α from immune spleen cells, mice were immunized with live virulent R. equi for 7, 17, 21, and 28 days. The highest production of IFN-γ and TNF- a from immune spleen cells after stimulation with R. equi antigens was observed in mice immunized for 7 days, and the production level of the spleen cell from mice immunized for 17 days became the same as that from normal mice. Sple … More en cells from mice immunized for 7 or 14 days were transfer to normal mice and the mice were challenged with virulent R. equi. The transfer immunity was effective in mice received spleen cell primed for 7 days, but not for 14 days. Immunized mice for 7 or 21 days with virulent R. equi were inoculated with anti-IL10 monoclonal antibody, and then challenged with virulent R. equi. There was no effect of anti-IL-10 antibody on the clearance of R. equi in the organs as compared with those of none-treated immune mice. On the other hand, in vitro experiment with anti-IL-10 monoclonal antibody showed effective function of IL-10 on the production of IFN-γ and TNF-α from immune spleen cells. Expression of CD44, CD62L, and CD45RB antigens on the spleen cells were analyzed by flow cytometory analysis using anti-CD44, CD62L, and CD45RB antibodies. However, there was no change between spleen T cells from immunized mice for 7 and 21 days. In conclusion, IL-10 might play a key role in the establishment and reduction of immune memory in R. equi infection in mice, however, the mechanism of inactivation or tolerance of T cells by R. equi infection remain unclear. Less