Fig. 4
From: Central memory CD4+ T cells are preferential targets of double infection by HIV-1
Only a fraction of primary CD4+ T cells are susceptible to HIV infection regardless of viral titer. a Representative fusion and productive infection (EGFP) data from 2 (of 4) healthy controls is shown. While viral fusion reaches a plateau at ~85–95 % of CD4+ T cells undergoing fusion—consistent with expression of CXCR4—EGFP expression reaches a plateau at far lower levels (less than 15 % for all donors tested). b Modeling of expected percentage of cells undergoing fusion or productive infection as a function of viral concentration. Different curves are expected if a fraction of virus is defective, a fraction of cells are infectible, or both