PPIA and HIV-1 infection: Disruption of the interaction between HIV-1 and CypA, either genetically or by cyclosporine A (CsA) addition, reduces the efficiency of HIV-1 infection (reviewed in (Campbell and Hope, 2015)), and some studies have indicated that CypA-CA interactions influence nuclear entry (De Iaco and Luban, 2014; Schaller et al., 2011).