Showing papers by "Marie-Thérèse Nugeyre published in 2009"

Gag p27-Specific B- and T-Cell Responses in Simian Immunodeficiency Virus SIVagm-Infected African Green Monkeys

Abstract: Nonpathogenic simian immunodeficiency virus SIVagm infection of African green monkeys (AGMs) is characterized by the absence of a robust antibody response against Gag p27 To determine if this is accompanied by a selective loss of T-cell responses to Gag p27, we studied CD4 + and CD8 + T-cell responses against Gag p27 and other SIVagm antigens in the peripheral blood and lymph nodes of acutely and chronically infected AGMs Our data show that AGMs can mount a T-cell response against Gag p27, indicating that the absence of anti-p27 antibodies is not due to the absence of Gag p27-specific T cells

Antigen-Presenting Cells Represent Targets for R5 HIV-1 Infection in the First Trimester Pregnancy Uterine Mucosa

Abstract: Background During the first trimester of pregnancy, HIV-1 mother-to-child transmission is relatively rare despite the permissivity of placental cells to cell-to-cell HIV-1 infection. The placenta interacts directly with maternal uterine cells (decidual cells) but the physiological role of the decidua in the control of HIV-1 transmission and whether decidua could be a source of infected cells is unknown. Methodology/Principal Findings To answer to this question, decidual mononuclear cells were exposed to HIV-1 in vitro. Decidual cells were shown to be more susceptible to infection by an R5 HIV-1, as compared to an X4 HIV-1. Infected cells were identified by flow cytometry analysis. The results showed that CD14+ cells were the main targets of HIV-1 infection in the decidua. These infected CD14+ cells expressed DC-SIGN, CD11b, CD11c, the Fc gamma receptor CD16, CD32 and CD64, classical MHC class-I and class-II and maturation and activation molecules CD83, CD80 and CD86. The permissivity of decidual tissue was also evaluated by histoculture. Decidual tissue was not infected by X4 HIV-1 but was permissive to R5 HIV-1. Different profiles of infection were observed depending on tissue localization. Conclusions/Significance The presence of HIV-1 target cells in the decidua in vitro and the low rate of in utero mother-to-child transmission during the first trimester of pregnancy suggest that a natural control occurs in vivo limiting cell-to-cell infection of the placenta and consequently infection of the fetus.

CD14+ cells are the main targets for HIV-1 infection in first trimester pregnancy human uterine mucosa

Abstract: During the first trimester of pregnancy, HIV-1 mother-tochild transmission (MTCT) is relatively rare despite the permissivity of placental cells to cell-to-cell HIV-1 infection. The invasive placental cells interact directly with the decidual cells (cells of the maternal uterine mucosa during pregnancy) in the first months of pregnancy; however the role of the decidua in the control of HIV-1 transmission remains unknown. The decidua has a characteristic leukocyte population containing natural killer cells (dNK), antigen-presenting cells (dAPC) and T lymphocytes. The aim of this study was to determine whether decidual cells could be potential targets to HIV-1 and could thus represent a risk for HIV-1 MTCT in utero.