Binding of radiolabeled TR339 or S1K70 virus to THP-1 control and DC-SIGN/L-SIGN-transfected cells. The viruses used were 39-C (open bars), 39-M (solid bars), 39-L (hatched bars), or 39-DMJ (crosshatched bars) and S1K70 (striped bars), which was derived from CHO cells. *, binding of TR339 derived from Lec1- and 1-DMJ-treated Pro5 CHO cells not tested on Δ35 THP-1 cells.