Suckling by Schistosoma mansoni-infected mothers restored IgG2a and TGF-β production, but not IL-6 and delayed-type hypersensitivity in IL-12/IL-23-deficient mice

Abstract INTRODUCTION Suckling by schistosomotic mice improves anti-ovalbumin (OA) antibody production, while delayed-type hypersensitivity (DTH) remains unaffected. This property of milk from schistosomotic mice was investigated in IL-12/IL-23-deficient mice (IL-12p40KO). METHODS We compared anti-OA DTH, IgG2a and cytokines in wild-type and IL-12p40KO mice suckled by infected (SIM) or non-infected (CONTROL) mothers. RESULTS SIM mice showed similar intensity and eosinophils in the DTH, which was abolished in IL-12p40KO and IL-12p40KO-SIM mice. In IL-12p40KO-SIM, IgG2a and TGF-β levels were higher, but IL-6 levels were lower. CONCLUSIONS Milk from schistosomotic mothers may evoke IgG2a without eliciting DTH in IL-12/IL-23 deficiencies, by changing TGF-β/IL-6 levels.

【摘要】
引言：感染血吸虫病小鼠的乳汁可增强抗卵清蛋白（ovalbumin, OA）抗体的生成能力，且不会对迟发型超敏反应（delayed-type hypersensitivity, DTH）造成影响。本研究针对感染血吸虫病小鼠乳汁的这一特性，在IL-12/IL-23缺陷小鼠（IL-12p40KO）中开展了相关探究。
方法：我们对比了野生型小鼠与IL-12p40KO小鼠分别由感染母鼠（schistosomotic-infected mothers, SIM）或未感染母鼠（对照组, CONTROL）哺乳后的抗卵清蛋白迟发型超敏反应、IgG2a抗体水平以及细胞因子表达情况。
结果：感染母鼠哺乳的小鼠的迟发型超敏反应强度与嗜酸性粒细胞浸润程度均与对照组无显著差异，但IL-12p40KO小鼠以及IL-12p40KO-SIM小鼠的该反应则完全被消除。在IL-12p40KO-SIM组中，IgG2a与转化生长因子-β（transforming growth factor-β, TGF-β）的表达水平升高，而白细胞介素-6（interleukin-6, IL-6）的表达水平则有所降低。
结论：感染血吸虫病母鼠的乳汁可在IL-12/IL-23缺陷个体中诱导产生IgG2a抗体，而不会引发迟发型超敏反应，其作用机制可能与调控TGF-β/IL-6的表达水平相关。