10 documents found, page 1 of 1
Gut disruption in HIV-2 infection despite reduced viremia
Fernandes, S. M.; Pires, A. R.; Ferreira, C.; Tendeiro, R.; Correia, L.; Paulo, S. E.; Victorino, R. M.; Sousa, A. E.HIV-2 infection is highly prevalent inWest Africa and has been increasingly observed in non-African countries, mostly associated with migratory populations [1]. It has a much more benign course and lower viremia than HIV-1 [2], though with similar clinical spectra. Half of the HIV-2 infected patients with less than 200 CD4+ T-cells/ml exhibit undetectable viremia, despite harbouring numbers of infected cells co...
Long-term immune reconstitution of naive and memory t cell pools after haploide...
Azevedo, R. I.; Soares, M. V.; Albuquerque, A. S.; Tendeiro, R.; Soares, R. S.; Martins, M.; Ligeiro, D.; Victorino, R. M.; Lacerda, J. F.; Sousa, A. E.Haploidentical hematopoietic stem cell transplantation (HSCT) constitutes an important alternative for patients lacking a human leukocyte antigen (HLA)-matched donor. Although the use of haploidentical donors is increasingly common, the long-term impact of generating a donor-derived immune system in the context of an HLA-mismatched thymic environment remains poorly characterized. We performed an in-depth assess...
Monocyte and myeloid dendritic cell activation occurs throughout HIV type 2 inf...
Cavaleiro, R.; Tendeiro, R.; Foxall, R. B.; Soares, R. S.; Baptista, A. P.; Gomes, P.; Valadas, Emília; Victorino, R. M.; Sousa, A. E.Monocytes and myeloid dendritic cells (mDCs) are important orchestrators of innate and human immunodeficiency virus (HIV)-specific immune responses and of the generalized inflammation that characterizes AIDS progression. To our knowledge, we are the first to investigate monocyte and mDC imbalances in HIV type 2 (HIV-2)-positive patients, who typically feature reduced viremia and slow disease progression despite...
Preserved CD4 T-cell telomere length during long-lasting HIV-2 infection --Manu...
Tendeiro, R.; Albuquerque, A. S.; Foxall, Russell B.; Cavaleiro, R.; Soares, R. S.; Baptista, A. P.; Soares, M. V.; Gomes, P.; Sousa, A. E.HIV-2 infection features a much slower course than HIV-1 infection, often asymptomatic for over 20 years, without antiretroviral therapy (ART). Nevertheless, CD4 T cells progressively decline, in direct correlation with immune activation and cell cycling. We report, for the first time, preserved telomere length within naive and memory CD4 subsets in prolonged HIV-2 infection despite the increased CD4 turnover.
Memory B-cell depletion is a feature of HIV-2 infection even in the absence of ...
Tendeiro, R.; Fernandes, S.; Foxall, R. B.; Marcelino, J. M.; Taveira, N.; Soares, R. S.; Baptista, A. P.; Cavaleiro, R.; Gomes, P.; Victorino, R. M.Objective: Memory B-cell loss has long been recognized as an important contributor to HIV immunodeficiency. HIV-2 infection, which is characterized by a slow rate of progression to AIDS and reduced to undetectable viremia, provides a unique model to investigate B-cell disturbances. Design and methods: B-cell subsets were evaluated in 38 HIV-2-infected individuals, along with markers of T-cell activation and ser...
Monocyte activation is a feature of common variable immunodeficiency irrespecti...
Barbosa, R. R.; Silva, S. P.; Silva, S. L.; Tendeiro, R.; Melo, A. C.; Pedro, E.; Barbosa, M. P.; Santos, M. C.; Victorino, R. M.; Sousa, A. E.Common variable immunodeficiency disorders (CVID), the most frequent cause of symptomatic primary immunodeficiency, are defined by impaired antibody production. Notwithstanding, T cell activation and granulomatous manifestations represent the main causes of CVID morbidity even in patients receiving immunoglobulin (Ig) G replacement therapy. Additionally, gut pathology is a frequent feature of CVID. In this stud...
Memory and naive-like regulatory CD4+ T cells expand during HIV-2 infection in ...
Foxall, R. B.; Albuquerque, A. S.; Soares, R. S.; Baptista, A. P.; Cavaleiro, R.; Tendeiro, R.; Gomes, P.; Victorino, R. M.; Sousa, A. E.Objective: The dynamics of CD4+ regulatory T cells (Treg) during HIV-1 infection remains unclear. To further investigate Treg in this context, we characterized, for the first time, this population in HIV-2-positive individuals. Although both HIV infections are associated with hyperimmune activation and CD4+ T-cell lymphopenia, most HIV-2-positive individuals display slower disease progression and low-to-undetec...
Potential impact of viral load and genetic makeup of HIV type 1 on mother-to-ch...
Pádua, E.; Parreira, R.; Tendeiro, R.; Nunes, Baltazar; Castela, J.; Soares, I.; Mouzinho, A.; Reis, E.; Paixão, M.T.HIV-1 mother-to-child transmission (MTCT) was evaluated in terms of the molecular characterization of the env and nef genomic regions and quantification of maternal RNA viral loads. Assignment of viral subtype was achieved by direct sequencing of PCR 1172 products amplified from proviral DNA in 45 HIV-1-nontransmitting mothers (NTM), along with 13 pairs of HIV-1-transmitting mothers (TM) and their infected chil...
Major depletion of plasmacytoid dendritic cells in HIV-2 infection, an attenuat...
Cavaleiro, R.; Baptista, A. P.; Soares, R. S.; Tendeiro, R.; Foxall, R. B.; Gomes, P.; Victorino, R. M.; Sousa, A. E.Plasmacytoid dendritic cells (pDC) provide an important link between innate and acquired immunity, mediating their action mainly through IFN-alpha production. pDC suppress HIV-1 replication, but there is increasing evidence suggesting they may also contribute to the increased levels of cell apoptosis and pan-immune activation associated with disease progression. Although having the same clinical spectrum, HIV-2...
IL-7 sustains CD31 expression in human naive CD4+ T cells and preferentially ex...
Azevedo, R. I.; Soares, M. V.; Barata, J. T.; Tendeiro, R.; Serra-Caetano, A.; Victorino, R. M.; Sousa, A. E.The CD31(+) subset of human naive CD4(+) T cells is thought to contain the population of cells that have recently emigrated from the thymus, while their CD31(-) counterparts have been proposed to originate from CD31(+) cells after homeostatic cell division. Naive T-cell maintenance is known to involve homeostatic cytokines such as interleukin-7 (IL-7). It remains to be investigated what role this cytokine has i...