Mechanism on the rise and fall of NK activity and CTL in tumor bearing mice in comparison with cryosurgery.

本研究观察了荷瘤小鼠脾淋巴细胞NK活性与细胞毒性T淋巴细胞（CTL）的关系，并探讨了冷冻肿瘤细胞接种后NK活性和CTL活性的升降机制，在此基础上，从肿瘤免疫治疗的角度讨论了冷冻手术的作用。[结果]荷瘤小鼠NK细胞至少部分属于T细胞谱系，NK细胞可转化为CTL。这可能是由于细胞表面的唾液酸调控所致，冷冻后的肿瘤细胞NK活性增强，但不能诱导CTL。MMC处理的肿瘤细胞NK活性降低，但能诱导CTL。提示NK细胞活性和CTL活性的升降与干扰素、前列腺素E、抑制性T细胞或白细胞介素2有关。

In this studies, the relationship between NK activity and cytotoxic T lymphocytes (CTL) were examined in splenic lymphocytes of tumor bearing mice.Furthermore, mechanisms on the rise and fall of NK activity and CTL were investigated after inoculation of cryo-destructed tumor cells.On the bases of these results, the usefulness of cryosurgery was discussed from a standpoint of tumor immunotherapy.[ Results ] NKcells belong, at least in part, to the T cell lineage, and the NK cells might be converted to CTL, in the tumor bearing mice. This possible pathway is considered to be due to control with sialic acid of cell surface.Cryo-destructed tumor cells enhanced NK activity, and could not induced CTL. On the contrary, tumor cells treated with MMC induced low NK activity,and could induce CTL. It was suggested that these rise and fall of NK activity and CTL related to interferon, prostaglandin E , suppressor T cells or interleukin 2.Thus cryosurgery augmented the non-specific immunity such as NK activity,but could not induce tumor-specific immunity.