Binding of HIV to DC-SIGNR transfected cells. 293T cells were
transiently transfected with the indicated expression plasmids. The
cells were incubated with p24-normalized virus stocks, vigorously
washed, and lysed in 0.5% Triton X-100, and then the content of bound
p24 was quantified by ELISA. The tropism of each virus is indicated
(R5, X4, or R5X4). All viruses are clade B except for the UG021 and
UG024 isolates, which are clade D. Data are presented as the percent of
recovered p24 antigen. The mean values ± SEM of four experiments
are shown. N.D., not done.