Figure 3

The effect of the origin of the intracellular portion of gp41 on infectivity. For selected clonal viruses isolated from patient 3 (inverted triangles), patient 4 (triangles), patient 5 (squares) or from the laboratory-adapted strain NL-AD8 (diamond), two types of recombinant reporter viruses were generated, one in which gp120 + only the extracellular domain of gp41 was derived from the clonal virus (pNL4-3-ΔectoENV-lucR, abscissa), and one in which gp120 and all of gp41 was derived from the clonal virus (pNL4-3-ΔENV-lucR vector, ordinate). The ability of these viruses to infect U373-R5 cells was compared by evaluating luciferase expression in the target cells 44 hours after infection. The infectivity of each pair of viruses was evaluated in three independent experiments, and each symbol represents the mean of these determinations. The dotted line is the line of identity. The correlation coefficient (Spearman) for the data shown is 0.86 (p < 0.0001).