Medeiros B M, Costa A M, Araújo P M, Falcão D P
Departamento de Cièncias Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP, Brasil.
Braz J Med Biol Res. 1997 Mar;30(3):401-5. doi: 10.1590/s0100-879x1997000300015.
Eight-week old conventional female Swiss mice were inoculated intravenously with Yersinia enterocolitica O:3. A second group of normal mice was used as control. Five mice from each group were bled by heart puncture and their spleens were removed for spleen cell collection on the 3rd, 5th, 7th, 10th, 14th and 21st day after infection. Immunoglobulin-secreting spleen cells were detected by the isotype-specific protein A plaque assay. Total immunoglobulin levels were determined in mouse serum by single radial immunodiffusion and the presence of autoantibodies was determined by ELISA. We observed a marked increase in the total number of cells secreting immunoglobulins of all isotypes as early as on the 3rd day post-infection and the peak of secretion occurred on the 7th day. At the peak of the immunoglobulin response, the total number of secreting cells was 19 times higher than that of control mice and most immunoglobulin-secreting cells were of the IgG2a isotype. On the 10th day post-infection, total serum immunoglobulin values were 2 times higher in infected animals when compared to the control group, and continued at this level up to the 21st day post-infection. Serum absorption with viable Y. enterocolitica cells had little effect on antibody levels detected by single radial immunodiffusion. Analysis of serum autoantibody levels revealed that Y. enterocolitica infection induced an increase of anti-myosin and anti-myelin immunoglobulins. The sera did not react with collagen. The present study demonstrates that Y. enterocolitica O:3 infection induces polyclonal activation of murine B cells which is correlated with the activation of some autoreactive lymphocyte clones.
将8周龄的雌性瑞士常规小鼠通过静脉注射接种小肠结肠炎耶尔森氏菌O:3。将另一组正常小鼠用作对照。在感染后的第3、5、7、10、14和21天，通过心脏穿刺从每组中取5只小鼠采血，并取出它们的脾脏用于收集脾细胞。通过同型特异性蛋白A空斑试验检测分泌免疫球蛋白的脾细胞。通过单向辐射免疫扩散法测定小鼠血清中的总免疫球蛋白水平，并通过酶联免疫吸附测定法测定自身抗体的存在情况。我们观察到，早在感染后第3天，分泌所有同型免疫球蛋白的细胞总数就显著增加，分泌高峰出现在第7天。在免疫球蛋白反应的高峰期，分泌细胞的总数比对照小鼠高19倍，并且大多数分泌免疫球蛋白的细胞是IgG2a同型。在感染后第10天，感染动物的血清总免疫球蛋白值比对照组高2倍，并在感染后第21天一直维持在该水平。用活的小肠结肠炎耶尔森氏菌细胞吸收血清对单向辐射免疫扩散法检测到的抗体水平影响很小。血清自身抗体水平分析显示，小肠结肠炎耶尔森氏菌感染导致抗肌球蛋白和抗髓磷脂免疫球蛋白增加。血清与胶原蛋白无反应。本研究表明，小肠结肠炎耶尔森氏菌O:3感染诱导小鼠B细胞的多克隆激活，这与一些自身反应性淋巴细胞克隆的激活相关。
