Nakamura M, Yoshida T, Isobe K, Iwamoto T, Jamshedur Rahman S M, Zhang Y H, Hasegawa T, Ichihara M, Nakashima I
Department of Immunology, Nagoya University School of Medicine, Japan.
Immunol Lett. 1991 Aug;29(3):235-40. doi: 10.1016/0165-2478(91)90176-b.
The effect of digestion of lymphocytes with neuraminidase and exoglycosidases on the secondary antibody response in vitro to sheep red blood cell (SRBC) antigen was tested. Treatment of spleen cells from SRBC-primed mice with 3 micrograms/ml of neuraminidase slightly but significantly augmented their plaque-forming cell response to SRBC, whereas treatment with 100 micrograms/ml of a mixture of exoglycosidases did not. Rather unexpectedly, however, treatment of the spleen cells with the mixture of both neuraminidase and exoglycosidases greatly augmented the response. This enzyme action was substrate specific inasmuch it was ablated by addition of mucin as a neuraminidase inhibitor to the enzyme mixture. The target of the enzyme activity was not glass-adherent macrophages, but was glass-non-adherent suppressor cells in the antigen-primed cell population. Evidence was provided that the phenotype of suppressor cells whose activity was ablated by the enzyme treatment was Thy-1+. It is suggested from these results that sialylated complex type oligosaccharides on antigen-primed T cells play a critical role in their suppressor activity.
测试了用神经氨酸酶和外切糖苷酶消化淋巴细胞对体外针对绵羊红细胞（SRBC）抗原的二次抗体反应的影响。用3微克/毫升神经氨酸酶处理经SRBC致敏小鼠的脾细胞，可轻微但显著增强其对SRBC的空斑形成细胞反应，而用100微克/毫升外切糖苷酶混合物处理则无此效果。然而，相当出乎意料的是，用神经氨酸酶和外切糖苷酶混合物处理脾细胞可极大地增强反应。这种酶作用具有底物特异性，因为向酶混合物中添加作为神经氨酸酶抑制剂的粘蛋白可消除该作用。酶活性的作用靶点不是玻璃黏附巨噬细胞，而是抗原致敏细胞群体中玻璃非黏附抑制细胞。有证据表明，其活性被酶处理消除的抑制细胞的表型为Thy-1+。从这些结果推测，抗原致敏T细胞上的唾液酸化复合型寡糖在其抑制活性中起关键作用。
