Homogeneous quasispecies in 16 out of 17 individuals during very early HIV-1 primary infection.
OBJECTIVE
To measure HIV-1 quasispecies diversity in very recently infected male and female plasma donors.


METHODS
HIV-1 RNA testing of blood and plasma donations was used to select anti HIV-1 antibody negative, HIV-1 RNA positive plasma samples from 13 males and four females undergoing primary infection. To determine whether these early viral populations were clonal or oligoclonal, heteroduplex mobility assays were performed on multiple independently generated envelope PCR products. Genetically heterogeneous quasispecies where subcloned and their divergent envelope variants sequenced.


RESULTS
Because of frequent plasma donations in this population, HIV-1 RNA quasispecies could be studied during very early primary infection. Heteroduplex mobility assays detected the presence of genetically distinct variants in four of the 17 plasma donors. DNA sequence analysis showed that one case was due to a G to A hyper-mutation event and that two cases were caused by the presence of in-frame insertions/deletions resulting in DNA heteroduplex mobility shifts. The early plasma quasispecies of one female contained highly divergent variants differing by up to 6% substitution and multiple insertions/deletions, a level of divergence unlikely to have been generated de novo following transmission. V3 loop sequences analysis indicated the presence of non-syncitium inducing genotypes in 14 out of 17 primary infection cases.


CONCLUSIONS
Plasma viremia is generally genetically homogeneous even during the very early phase of primary infection when viremia is first detected and still rising exponentially. Evidence for the transmission of multiple variants was detected in only one out of four women and none of 13 men undergoing primary infection with subtype B HIV-1.
Delwart
Eric
E
Blood Centers of the Pacific, San Francisco, California, USA.
Magierowska
Magdalena
M
Royz
Maya
M
Foley
Brian
B
Peddada
Lorraine
L
Smith
Richard
R
Heldebrant
Charles
C
Conrad
Andrew
A
Busch
Michael
M
D001483:Base Sequence; D001782:Blood Donors; D004279:DNA, Viral; D005260:Female; D014644:Genetic Variation; D015483:HIV Antibodies / Q000097:blood; D015699:HIV Envelope Protein gp120 / Q000235:genetics; D015658:HIV Infections / Q000097:blood / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009692:Nucleic Acid Heteroduplexes; D010446:Peptide Fragments / Q000235:genetics; D012367:RNA, Viral / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid; D013997:Time Factors; D014766:Viremia / Q000821:virology
D004279:DNA, Viral; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D009692:Nucleic Acid Heteroduplexes; D010446:Peptide Fragments; D012367:RNA, Viral