The factor was released from immune cells called natural killer (NK) cells in the liver, but only if another immune cell, the macrophage, was present.

该因子由肝脏中被称为自然杀伤(NK)细胞的免疫细胞释放，但是只有当另一种免疫细胞，巨噬细胞存在时才释放。

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In this paper the research on immunity of the red-cell material base, immune function of erythrocyte, influencing factor and other research hotspots in recent years were mainly elucidated.

对红细胞免疫的物质基础、功能、影响因素及近年来对红细胞免疫研究的热点问题作一综述。

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