Lethal graft-vs-host disease (GVHD) develops after transfer of CTL- depleted spleen and bone marrow cells from C57BL/6 (B6) mice to irradiated MHC class II disparate (B6xbm12)F1 recipients. Onset of lethal GVHD is significantly delayed in (bm1xbm12)F1 recipients of the same donor inoculum despite the additional MHC class I disparity (H-2K(bm1)). To investigate the basis of this protective effect, hybridomas were generated from T cells activated in vivo during GVHD in both strain combinations. T cells from B6→(B6xbm12)F1 mice generated a significantly higher frequency of B6.C-H- 2(bm12) (bm12)-specific T hybridomas (110/178, 62%) than T cells from B6→(bm1xbm12)F1 mice (102/218, 47%). Some bm12-specific T hybridomas exhibited lesser responses to (bm1xbm12)F1 than to (B6xbm12)F1 APC. Moreover, bm1 peptides spanning a 14-amino acid region that includes the three amino acids that differ from H-2K(b) were found to inhibit responses of some bm12-specific T hybridomas and to decrease significantly responses of splenic B6 CD4+ T cells to bm12 APC. Notably, the frequency of bm12-reactive hybridomas susceptible to inhibition by bm1 peptides generated from B6→(B6xbm12)F1 mice was significantly greater than that generated from B6→(bm1xbm12)F1 mice. Additional analysis using L cell transfectants indicated that hybridomas responding to the bm12 mutation at position 70 alone were rarely inhibited by bm1 peptides. The data indicate that expression of bm1-derived peptides can influence the frequency and specificity of alloreactive CD4+ T cells stimulated in vivo and thus may alter the course of GVHD.
|Original language||English (US)|
|Number of pages||12|
|Journal||Journal of Immunology|
|State||Published - Jan 1 1995|
ASJC Scopus subject areas
- Immunology and Allergy