In vivo monitoring of splenocytes in NMRI nu/nu- And nu/+,mice during Lewis lung tumor progression or regression

Splenocytes of T-cell deficient NMRI nu/nu- mice (n=15) and of inbred immunocompetent NMRI nu/+,littermates (n=18) significantly (p<0.05) increased during Lewis lung (LL) tumor growth and eventually decreased. Half of the heterozygous NMRI nu/+,- mice rejected the tumors (LL-regressors). Zymosan-induced and lucigenin-amplified chemiluminescence (CL) of splenic polymorphonuclear leukocytes (PMN) and -precursors significantly (p<0.05) increased in NMRI nu/+,- mice with progressing tumors (LL-progressors) on the 3rd and in LL-regressors and nude mice on the 7th day after tumor inoculation. It subsequently decreased although numbers of PMN/- precursors further multiplied predominantly in the LL-progressors. Another peak of CL was found in those animals after the 20th day. Splenic lymphocytes significantly (p<0.05) increased in all mice from day 5 forward and dropped to original numbers between the 20th and 25th days. Maximal lymphocyte counts were significantly (p<0.05) lower in nude mice as compared to the NMRI nu/+,- littermates. The splenic T-/B-ratio significantly (p<0.005) correlated in LL-regressors and did not in LL-progressors. This correlation could be a suitable marker for tumor progression in NMRI nu/+ mice bearing LL-tumors.