J:56029

Lymphocytes of mouse strain BALB/cHeA and STS/A differ in their response to the CD3 antibody. BALB/c lymphocytes are intermediate responders while STS lymphocytes do not respond to this stimulus. The authors used recombinat congenic strains of BALB/c - c-STS/Dem (CcS/Dem) series to examine the genetic basis of proliferative response to anti-CD3. Proliferative response to anti-CD3 was examined in 170 (CcS-9 x CcS-11)F2 hybrids. CcS-9 was a high responder strain while CcS-11 is a low responder strain. Statistical evaluation revealed linkage of rsponse to higher doses (3.0 ug/ml) of CD3 mAbb to the marker D9Mit15 (corrected P = 0.00065). This data indicated the presence of a locus Tria5 in this region. Strain CcS-9 carries on this chromosome a 3.4 cM region of STS origin. No effect of age or sex was found. Trf is a putative candidate gene in this region.