FIG. 2.

Sensitivity of gp41 M/O primers in detecting HIV-1 RNA in plasma with known copy numbers (A) and early seroconverters (B). (A) Normal plasma was spiked with known copy numbers of subtype B viruses prior to RNA extraction and amplification. (B) RNA extracts from longitudinal plasma specimens from five persons (panel no. 946 and 948 to 951) during the window period were amplified with gp41 M/O primers. The results with HIV-1 antibody (Ab), p24 antigen (Ag), and three commercial RNA tests (RNA) are shown as negative (−) and positive (+) at the bottom of each panel.