Detection of cellular immunity to murine sarcoma virus-induced tumors by leukocyte adherence inhibition
Mortensen, R.F.
Journal of the National Cancer Institute 62(1): 157-163
1979
ISSN/ISBN: 0027-8874 PMID: 214608 Document Number: 142280
The leukocyte adherence inhibition (LAI) response of C57BL/6 mice inoculated with a regressing strain of Moloney murine sarcoma virus (M-MuSV) was measured in a microassay with 3 M KCl extracts of the RBL-5 or FBL-3 leukemia cell line. The LAI reactivity of spleen and peritoneal cells of mice bearing M-MuSV-induced tumors was antigen-specific, reached its highest level when the tumors began to regress (12-14 days) and developed more rapidly in M-MuSV-immune mice following a secondary challenge with RBL-5 or FBL-3 cells. The kinetics of the LAI response was monophasic, and the development and magnitude of the reactivity correlated with the size of the M-MuSV-induced tumor. Extensive cross-reactive LAI activity was observed with extracts from RBL-5 and FBL-3 cells. Extracts from normal syngeneic tissues, allogeneic tumor cells and syngeneic tumor cells induced by nonviral agents did not elicit an LAI response with lymphoid cells from mice with M-MuSV-induced tumors. Indirect assays detected the production of a mediator(s) of LAI in response to intact cells and extracts of RBL-5 and FBL-3. LAI reactivity was lower in magnitude and rapidly lost in unsensitized C57BL/6 mice bearing progressively growing, as opposed to regressing, FBL-3 tumors. LAI reactivity is a good indicator of host responsiveness to M-MuSV-induced tumors.