In the present study, we have further elucidated the cellular basis for defective antibody production during malaria: we showed that immunization with adjuvanted protein during acute Plasmodium infection activates immunogen-specific CD4+ T cells, but fails to elicit the Tfh cells necessary to support a robust immunogen-specific B cell response, correlating with diminished B cell expansion and decreased serum antibody titers. Here, CD4 is linked to malaria.