Replication of HIV-1 with U5 and PBS sequence altered to be complementary to the anticodon loop and 3' 18 nucleotides of tRNAIle, tRNAMet, tRNAPro and tRNATrp in PBMC. Infections were initiated with transfection supernatant containing approximately 200 pg of p24 antigen in a volume of 10 mLs of media, giving a final p24 level of 20 pg/mL on day zero. Supernatants were assayed for p24 viral antigen every 7 days for a period of 42 days. At 14-day intervals, 5 × 106 fresh PHA stimulated PBMC were added to each culture. Two additional separate infections produced very similar replication patterns for each virus (data not shown). Squares are NL4-3 wild type; diamonds are NL4-3-Met-AC; open circles are NL4-3-Ile-AC; closed circles are NL4-3-Pro-AC.