Summary of genotypic coreceptor predictions and phenotypic coreceptor determinations. The HIV-1 env C2V5 sequence was amplified from genomic DNA isolated from patient derived PBMCs at the indicated time points as described before . Coreceptor usage was predicted either with WebPSSM (score of sequences shown) or geno2pheno. Patient derived HIV-1 was amplified once on donor PBMCs and was used to infect PBMCs or IsnoR5 cells. Viral replication in the analyzed cells was determined by p24 Elisa  and is indicated as + or -. In a second confirmatory assay, patient-derived virus or lab strains were used to infect TZM-bl cells or TZM-bl cells in the presence of Vicrivroc (R5i) and infection was monitored by lacZ staining. Positive cells were counted and the numbers are indicated. The last column gives the coreceptor use deduced from in vitro phenotyping. N.d. = not done.