Suzuki Y, Joh K, Kobayashi A
Department of Parasitology, Jikei University School of Medicine, Tokyo, Japan.
Cell Immunol. 1987 Dec;110(2):218-25. doi: 10.1016/0008-8749(87)90117-1.
In acute Toxoplasma infection, anti-sheep erythrocytes (SRBC) antibody responses were strongly suppressed in the infected C57BL/6 mice, and the mice produced low titers of only 2-mercaptoethanol (2-ME)-sensitive antibodies but not 2-ME-resistant antibodies. By contrast, the infected BALB/c mice produced much higher titers of both 2-ME-sensitive and -resistant anti-SRBC antibodies than the infected C57BL/6 mice. In anti-Toxoplasma antibody responses, the 2-ME-resistant antibody titers were significantly lower in the infected C57BL/6 mice than in the BALB/c mice in the early phase of infection, suggesting that the suppressive effect of Toxoplasma infection affects antibody responses to Toxoplasma itself as well as to the unrelated antigen, SRBC. A histological study revealed that in the infected C57BL/6 mice, a large number of acid phosphatase-positive, macrophage-like cells infiltrated into the follicles of their spleens, and an involution of follicles occurred in the acute phase of infection. This histological change was not observed in the infected BALB/c mice. The infected C57BL/6 mice, which had the suppressed anti-Toxoplasma antibody responses, made five times as many as cysts in their brains as compared with the BALB/c mice at the fifth week of infection.
在急性弓形虫感染中，感染弓形虫的C57BL/6小鼠抗绵羊红细胞（SRBC）抗体反应受到强烈抑制，这些小鼠仅产生低滴度的对2-巯基乙醇（2-ME）敏感的抗体，而不产生对2-ME有抗性的抗体。相比之下，感染弓形虫的BALB/c小鼠产生的对SRBC的2-ME敏感和抗性抗体滴度均远高于感染弓形虫的C57BL/6小鼠。在抗弓形虫抗体反应中，感染弓形虫的C57BL/6小鼠在感染早期对2-ME有抗性的抗体滴度显著低于BALB/c小鼠，这表明弓形虫感染的抑制作用不仅影响对弓形虫自身的抗体反应，还影响对无关抗原SRBC的抗体反应。组织学研究显示，在感染弓形虫的C57BL/6小鼠中，大量酸性磷酸酶阳性的巨噬细胞样细胞浸润到脾脏滤泡中，并且在感染急性期出现滤泡退化。在感染弓形虫的BALB/c小鼠中未观察到这种组织学变化。感染弓形虫的C57BL/6小鼠抗弓形虫抗体反应受到抑制，在感染第5周时，其脑内囊肿数量是BALB/c小鼠的5倍。
