DIFFERENTIAL SUSCEPTIBILITY OF SPLEEN CELLS FROM C3H/HeN (H‐2k) AND C3HfB/HeN (H‐2kv1) MOUSE STRAINS TO CYTOTOXICITY BY MONOCLONAL ANTI‐Kk ANTIBODY (CLONE 11‐4)

SUMMARY Spleen cells from C3HfB/HeN mice (H-2kv1) were markedly less susceptible to lysis by monoclonal anti-Kk antibody (Clone 11-4) than spleen cells from C3H/HeN mice (H-2k). Less than 50% of C3HfB/HeN cells were lysed even at the highest antibody concentration tested compared to 70% of C3H/HeN cells. The difference in end point titre of the antibody tested on cells from the two strains was 5-10-fold. Similar differences were not observed using the conventional H-2Kk-typing antiserum (D-23).