After volunteers are recruited, screened and enrolled in the study, they will be randomized to group C, D, or E. Each group will enroll 10 patients and 2 controls. The placebo control for TBC-3B will be standard vaccinia vaccination administered at doses no higher than that administered by scarification; the placebo control for MN rgp120 will be alum. Group C will receive undiluted TBC-3B by scarification, at months 0 and 2. Group D will receive diluted TBC-3B intradermally at month 0 and undiluted TBC-3B at month 2. Group E will receive diluted TBC-3B subcutaneously at month 0 and undiluted TBC-3B at month 2. At months 8 and 12 all groups will receive MN rgp 120/HIV-1 in alum intramuscularly.