A HELPER T-CELL EPITOPE OF THE E7 PROTEIN OF HUMAN PAPILLOMAVIRUS TYPE-16 IN BALB C MICE/

The helper T-cell response to the E7 protein of human papillomavirus t ype 16 (HPV16) was studied using BALB/c (H-2(d)) mice. Twenty-two over lapping synthetic peptides spanning the HPV16 E7 protein were split in to 6 groups. Mice were sensitized using mixtures of synthetic peptides corresponding to each of the groups. Lymph node cell suspensions were cultured with the corresponding mixture of synthetic peptides that wa s used for sensitization. Two mixtures induced a proliferative respons e. Analysis of the individual peptides from these mixtures showed that two (overlapping) peptides induced a proliferative response. This res ponse was mediated by CD4+ cells. The common region of the two peptide s was found to be a single epitope, and a minimal epitope was demonstr ated (AHYNIVTFCCK). In conclusion, in contrast to others, we demonstra ted a helper T-cell response in BALB/c mice. This may be due to the fa ct that we used synthetic peptides as immunizing agent. The helper T-c ell epitopes in HPV16 E7 demonstrated previously are partly overlappin g with the (minimal) epitope demonstrated here, underlining the 'publi c' nature of the epitope.