Lallemant M, Barin F, Jourdain G, Ngo-Giang-Huong N, Brunet S, Warachit B, Ngampiyasakul C, Sriwacharakarn C, Hansudewechakul R, Watanayothin S, Karnchanamayul W, Vithayasai V, Thanasiri P; International Conference on AIDS (15th : 2004 : Bangkok, Thailand).
Int Conf AIDS. 2004 Jul 11-16; 15: abstract no. ThPeA6968.
Universite F Rabelais, Tours, France
Background: A broadly neutralizing response may be key to the success of a vaccine against HIV-1. Perinatal transmission is a unique situation where the role of maternal antibodies can be studied. Conflicting results have been observed, mainly due to the nature of the viruses used in neutralizing assays, i.e. laboratory adapted strains or homologous viruses. We focused on antibodies neutralizing highly genetically diverse primary isolates, assuming that only such broadly neutralizing antibodies might be associated with vertical transmission. Methods: We compared baseline serums of 28 transmitting (cases) and 62 non-transmitting mothers (controls) who participated in a clinical trial assessing various zidovudine durations for the prevention of perinatal HIV in Thailand (no breastfeeding). Neutralization titers towards primary isolates of clades B (FRO), F (GIL), CRF01-AE (MBA) and CRF02-AG (KON) were determined by a seroneutralization assay using CD4+CXCR4+CCR5+ HeLa cells harboring the Lac Z reporter gene instead of labor intensive tests on PBMCs. Antibodies to gp41 (IDE TM), V3 and p24 were measured by ELISA. Cases and controls were matched on viral load and zidovudine prophylaxis duration. The association between each antibody titer (high, medium or low/undetectable) and transmission was tested using conditional logistic regression. Results: Perinatal transmission was associated with medium or low antibody titers against GIL (P=0.030), MBA (P=0.012) and p24 (P=0.046), and with high titers against gp41 (P=0.004) and V3 (P=0.045), but not with antibodies to KON and FRO (P=0.2 and 0.4, respectively). Upon multivariate analysis, medium and low antibody titers against MBA and p24, and high titers against gp41 remained independently associated with transmission. Conclusion The association between transmission and high antibody levels against gp41 and V3 confirms previous reports. High titers of maternal neutralizing antibodies might protect against vertical transmission.
Publication Types:
Keywords:
- Acquired Immunodeficiency Syndrome
- Antibodies
- Antigens, CD4
- Case-Control Studies
- Disease Transmission, Vertical
- HIV Antibodies
- HIV Infections
- HIV Seropositivity
- HIV-1
- Humans
- Receptors, CCR5
- Receptors, CXCR4
- Thailand
- Viral Load
- Zidovudine
- immunology
- transmission
Other ID:
UI: 102280752
From Meeting Abstracts