title: Virologic risk factors for vertical transmission of HIV type 1 in Puerto Rico.
abstract: HIV-1 vertical transmission in Puerto Rico has decreased significantly due to the implementation of antiviral therapy. Several studies have shown that the phenotype of the HIV-1 isolates initially recovered from infected infants has generally been one that replicates rapidly, infects macrophages, and preferentially use the CCR5 coreceptor. Our hypothesis is that viral genotypic and phenotypic differences exist between HIV-1 nontransmitter and transmitter mothers. Viral DNA samples and virus isolates were analyzed from a Puerto Rican perinatal population. Heteroduplex tracking assay (HTA) was performed on DNA samples to detect env V3 evolutionary variants and the extent of heterogeneity within each sample. HIV-1 C2-V3 variants were cloned from each patient to study sequence variation among the groups. Differences in replication kinetics of viral isolates in macrophage and GHOST CCR5 cells were analyzed by use of repeated measures linear regression analysis. HTA analysis showed that only two nontransmitter patient samples showed the presence of evolutionary variants. Phylogenetic analysis between maternal-infant pairs showed that transmission of a single maternal variant occurred, with the exception of one sample pair. When evaluating amino acid sequences from cloned PCR products, nontransmitting mothers appear to have a higher number of distinct sequences than both the transmitting mothers (p = 0.0410) and the infected infants (p = 0.0315). Analysis of replication kinetics indicated that transmitters showed faster replication kinetics in GHOST CCR5 cell cultures at 12 days postinfection (p = 0.0434) and 15 days postinfection (p = 0.0181). In conclusion, viral homogeneity and rapid replication kinetics were correlated with vertical transmission.
authors.affiliation: Department of Microbiology and Medical Zoology, University of Puerto Rico, School of Medicine, San Juan, Puerto Rico 00936.
authors.forename: M A
authors.initials: MA
authors.lastname: Arroyo
authors.forename: H
authors.initials: H
authors.lastname: Tien
authors.forename: M
authors.initials: M
authors.lastname: Pagán
authors.forename: R
authors.initials: R
authors.lastname: Swanstrom
authors.forename: G V
authors.initials: GV
authors.lastname: Hillyer
authors.forename: C L
authors.initials: CL
authors.lastname: Cadilla
authors.forename: L M
authors.initials: LM
authors.lastname: Meléndez-Guerrero
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000635:transmission*; D000293:Adolescent; D000328:Adult; D005260:Female; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000235:genetics; D015497:HIV-1 / Q000145:classification* / Q000502:physiology; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D007700:Kinetics; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D011247:Pregnancy; D012307:Risk Factors; D014779:Virus Replication
chemical_list: D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments