Study on suppression of interferon-γ production by nematode antigens

在本项目（2002-2003）中，我们研究了来自巴拉斯利Nippostrongylus barasiliensis （Nb）和Ascaris suum （As）成虫的排泄-分泌抗原（ES）的干扰素(IFN)-γ产生抑制活性，并指出以下几点；Nb-ES抗原及其部分纯化部分抑制大鼠和小鼠T细胞产生IFN-γ。部分纯化的As-ES也能抑制大鼠或小鼠T细胞产生IFN-γ，但蠕虫体液没有。经过离子交换和抗Nb-ES亲和层析，我们得到的Nb-ES片段对大鼠T细胞产生IFN-γ的抑制活性比Nb-ES粗抗原高20倍。我们还表征了Nb-ES中的IFN-γ抑制分子(s)。1) IFN-γ抑制分子(s)分子量为50-100kD。2)该分子对56℃，30 min的处理有一定的抗性，但对95℃，30 min的处理有一定的敏感性。

In this project (2002-2003), we examine interferon (IFN)-γ production suppressing activity in excretory-secretory antigens (ES) derived from Nippostrongylus barasiliensis (Nb) and Ascaris suum (As) adult worms and pointed out the followings;1.Nb-ES antigen and its partially-purified fraction suppressed IFN-γ production by both rat and mouse T cells.2.Partially-purified As-ES also suppressed IFN-γ production by rat or mouse T cells, but the body fluid of the worm did not.3.After ion-exchange and anti-Nb-ES affinity chromatography, we obtained the Nb-ES fraction that has 20 times higher activity in suppression of IFN-γ production by rat T cells comparing with crude Nb-ES antigen.4.We also characterized the IFN-γ suppressing molecule(s) in Nb-ES.1)Molecular weight of the IFN-γ suppressing molecule(s) is 50-100kD.2)The molecule(s) is resistant to 56℃,30 min. but partially sensitive to 95℃,30 min treatment3)The molecule(s) is sensitive to periodate treatment.