Fig. 3.

Fusin renders CD4⁺ nonhuman cells susceptible to productive HIV-1 infection. Transformants (filled symbols, fusin; open symbols, the control lacZ) of the CD4⁺ Mv 1 Lu cell line were seeded as monolayers in 24-well tissue culture plates (50,000 cells per well). To each well, 1000 median tissue culture infectious doses (TCID₅₀) of HIV-1 (Lai. LAV isolate) were added, and the plates were incubated 4.5 hours at 37°C. The wells were washed four times with PBS, and 1.2 ml of culture medium supplemented with G418 was added. An aliquot (0.2 ml) was removed immediately as a zero time point; at the indicated times, aliquots (0.25 ml) were removed and replaced with the same volume of fresh media. Samples were assayed for p24 content with an enzyme-linked immunosorbent assay kit (DuPont).