Studies of the thymus in mice bearing the Lewis lung carcinoma. II. Modulation of thymic natural killer activity by thymulin (FTS-Zn) and the antimetastatic effect of zinc.
Modulation of thymic natural killer (NK) cell activity by the serum thymic factor (thymulin or FTS-Zn) was demonstrated in mice carrying the Lewis lung carcinoma (3LL). Thymulin decreased the increased NK activity found in amputated (tumor) tumor-bearing mice and induced a significant NK activity in nonamputated mice, normally devoid of such activity. Zinc had no effect in either case. Histological studies revealed that zinc prevented the tumor-induced thymic atrophy. A clear-cut decrease in the number of lung metastases was observed in zinc-treated mice. This effect was suppressed by concomitant administration of thymulin to amputated mice. The thymic dependency of the anti-metastatic action of zinc as well as the mode of action of thymulin on NK cell activity in tumor-bearing animals is discussed.
D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D005260:Female; D007694:Killer Cells, Natural / Q000276:immunology*; D008175:Lung Neoplasms / Q000188:drug therapy / Q000276:immunology* / Q000556:secondary; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000188:drug therapy / Q000276:immunology / Q000556:secondary; D009929:Organ Size / Q000187:drug effects; D013934:Thymectomy; D013935:Thymic Factor, Circulating / Q000032:analysis; D013950:Thymus Gland / Q000033:anatomy & histology / Q000473:pathology; D013951:Thymus Hormones / Q000008:administration & dosage / Q000494:pharmacology*; D015032:Zinc / Q000008:administration & dosage / Q000494:pharmacology*
D013951:Thymus Hormones; C032805:thymalin; D013935:Thymic Factor, Circulating; D015032:Zinc