Natural killer cell activity in mice bearing Lewis lung carcinoma

• Main Author: Wheeler, Elizabeth H.
• Other Authors: Young, M. Rita
• Format: Others
• Published: 2011
• Subjects: Killer cells.; Prostaglandins.; Macrophages.; Tumors > Immunological aspects.; Mice > Physiology.
• Online Access: http://cardinalscholar.bsu.edu/handle/handle/183124; http://liblink.bsu.edu/uhtbin/catkey/416656

Natural killer (NK) cells are important in limiting tumor dissemination. The NK activity in C57B1/6 mice bearing Lewis lung carcinoma (LLC) was monitored during tumor development. During the initial period of tumor growth, NK activity was enhanced. As tumor growth progressed, NK activity became suppressed. Depletion of macrophages from the spleen cells of tumor-bearing mice restored the NK cytotoxic response. Plasma prostaglandin E2 (PGE2) concentrations were measured by a radioimmunoassay and found to become elevated during the course of tumor growth. To determine whether the suppressed NK activity might have been a result of the elevated levels of PGE2, mice were treated with a prostaglandin synthesis inhibitor, indomethacin. Indomethacin treatment prevented the rise in plasma PGE2 concentrations and the suppression in NK activity. These results support the hypothesis that the suppression of NK activity in tumor bearers is mediated by PGE2 which might be produced by the host's suppressor macro-phages.