Figure 4

Receptor and co-receptor requirements of cloned env. Pseudoviruses expressing cloned env were titered on HeLa cell lines engineered to express various levels of CD4 and CCR5. To normalize between different pseudovirus preparations, titers are expressed as a ratio of the titer on the cell line divided by the titer on TZMbl cells. (A) TZMbl, (B) JC37, (C) JC10, (D) RC49, (E) RC23. Results are an average of 3 independent experiments performed in duplicate. Average number of receptor and co-receptor molecules per cell as reported by Platt et al [21] is inset in the charts. Filled triangle = infant, empty circle = maternal. Pairwise statistical analysis performed using the Mixed Model ANOVA with mother-infant pairings included as random effects indicated that mean maternal and infant titers did not vary significantly across pairs.