Immunization with Human Immunodeficiency Virus Type 1 rgp120W61D in QS21/MPL Adjuvant Primes T Cell Proliferation and C-C Chemokine Production to Multiple Epitopes within Variable and Conserved Domains of gp120W61D

Human immunodeficiency virus type 1 (HIV-1) gp120W61D—specific T cell lines (TCL) were generated from an HIV-1—seronegative volunteer who received rgp120W61D in QS21/MPL adjuvant with emulsion. TCL were challenged with pools of consecutive, overlapping peptides spanning the gp120W61D sequence and then with the individual peptides of the immunostimulatory pool. T cell epitopes were found within both variable and conserved domains, and there was no evidence of a single immunodominant epitope. The two most frequently recognized peptides were located in the C1 domain and in the C-terminal region of the V3 loop. Several TCL were shown to recognize multiple peptides from nonoverlapping regions. Peptides from both conserved and variable domains were capable of inducing MIP-1α, MIP-1β, and RANTES production. When tested against the equivalent peptide from the HIV-1IIIB sequence, however, TCL were able to tolerate only minor conserved changes in the amino acid sequence.