There was a decrease from 60% to 10% in generation of peptide-specific T cells with vegetable-derived IFA in comparison to beef-derived IFA. Decreased immunogenicity of vegetable-derived IFA was noted with a decrease in skin reactions. Beef-derived LFA contains more adjuvants noted by the improved IL-2 response of patients with metastatic melanoma who received the vaccination. The gene discussed is IL2; the disease is metastatic melanoma.