Trophoblasts are productively infected by CD4-independent isolate of HIV type 1.
Evidence for HIV-1 infection of trophoblasts is discordant. Utilizing highly purified full-term trophoblasts, we demonstrate that full-term trophoblasts express CXCR4 but are negative for CCR5 and CD4 cell surface proteins. Full-term trophoblasts were refractory to infection by HIV-1 IIIB and primary isolates of HIV-1. However, full-term trophoblasts could be infected by a CD4-independent, CXCR4-utilizing HIV-1 strain, as demonstrated by substantial p24 (5.5 ng/ml) levels and HIV-1 gag/pol DNA content (3050 copies/microg) 7 days postinfection. These data illustrate that trophoblasts express the essential host factors for productive HIV-1 infection and that the block to HIV-1 infection may be at the level of entry. In additional, our data suggest that CD4-independent mechanisms of infection may play a role in promoting in utero HIV-1 transmission.
Al-Harthi
Lena
L
Department of Immunology/Microbiology, Rush-Presbyterian-St. Luke's Medical Center, Rush University, Chicago, Illinois 60612, USA. lalharth@rush.edu.
Guilbert
Larry J
LJ
Hoxie
James A
JA
Landay
Alan
A
D015704:CD4 Antigens / Q000032:analysis / Q000378:metabolism; D002478:Cells, Cultured; D018920:Coculture Techniques; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D015750:Genes, gag; D015751:Genes, pol; D016655:HIV Core Protein p24 / Q000032:analysis; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000378:metabolism; D006801:Humans; D019713:Receptors, CCR5 / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000032:analysis / Q000378:metabolism; D014327:Trophoblasts / Q000378:metabolism / Q000821:virology*
D015704:CD4 Antigens; D004279:DNA, Viral; D016655:HIV Core Protein p24; D019713:Receptors, CCR5; D019718:Receptors, CXCR4