In addition, we compare the efficiency of Bcl-6/Bcl-xL B cell immortalization of CD27+CD21+ and CD27-CD21- B cells from HIV-1-infected individuals and from malaria convalescent individuals, and demonstrate a strategy to isolate HIV-1-specific neutralizing antibodies by combining Bcl-6/Bcl-xL B cell immortalization with the TZM-bl neutralization assay. Here, CD27 is linked to malaria.