Effects of carnosine on NK cell number and cytotoxic activity in spleen lymphocytes of restraint-stressed mice.

Spleen lymphocyte samples containing 1×106 cells were stained with anti-CD3 (FITC)/anti-NK1.1 (PE) antibody to assess the percentage of NK cells (NK+CD3−) by flow cytometry. NK cell number was calculated according to NK cell percentage and total spleen lymphocyte number. In the determination of NK cell cytotoxic activity, target cells were YAC-1 cells. YAC-1 cells, stained with DiO, were mixed with freshly isolated spleen lymphocytes and incubated. Then PI was added to the mixtures. After incubation, NK cell activity was determined by flow cytometry. The results represent mean ± S.E.M. obtained from 10 animals in each group. The significance of differences from normal group was at##p*p**p