9 documents found, page 1 of 1
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...
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 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...
First use of thymus transplantation therapy for FOXN1 deficiency (nude/SCID) : ...
Markert, M. L.; Marques, J. G.; Neven, B.; Devlin, B. H.; McCarthy, E. A.; Chinn, I. K.; Albuquerque, A. S.; Silva, S. L.; Pignata, C.FOXN1 deficiency is a primary immunodeficiency characterized by athymia, alopecia totalis, and nail dystrophy. Two infants with FOXN1 deficiency were transplanted with cultured postnatal thymus tissue. Subject 1 presented with disseminated Bacillus Calmette-Guérin infection and oligoclonal T cells with no naive markers. Subject 2 had respiratory failure, human herpes virus 6 infection, cytopenias, and no circul...
Increased frequency of CD25dim CD4+ T-cells in HIV-2 infection, a naturally occ...
Foxall, R. B.; Soares, R. S.; Albuquerque, A. S.; Cortesão, A. C.; Victorino, R. M.; Sousa, A. E.The ability to maintain the CD4-memory pool is currently considered one of the main determinants of AIDS progression. Like HIV-1, HIV-2 infection is characterized by progressive hyper-immune activation, yet it is associated with slower rates of CD4-loss and reduced viremia irrespective of disease stage. In contrast to HIV-1, we observed an increased proportion of CD4(+) T-cells expressing CD25 in HIV-2 infected...
Gag-specific CD4+ T-cell frequency is inversely correlated with proviral load a...
Foxall, R. B.; Cortesão, C. S.; Albuquerque, A. S.; Soares, R. S.; Victorino, R. M.; Sousa, A. E.Human immunodeficiency virus type 2 (HIV-2) infection, unlike HIV-1 infection, is normally characterized by low rates of CD4 depletion and low-to-undetectable viremia. We found that the frequency of Gag-specific CD4(+) T cells featured positive correlations with the expression of markers of CD4 activation and a negative correlation with peripheral blood mononuclear cell-associated proviral load in infection wit...
Low CD4 T-cell counts despite low levels of circulating HIV : insights from the...
Albuquerque, A. S.; Foxall, R. B.; Cortesão, C. S.; Soares, R. S.; Doroana, M.; Ribeiro, A.; Lucas, M.; Antunes, F.; Victorino, R. M.; Sousa, A. E.A significant proportion of HIV-1+ patients with suppression of viremia under antiretroviral therapy fail to recover CD4(+) T-cell counts (ART-Discordants). Similarly, untreated HIV-2+ patients can also exhibit major CD4 depletion in spite of undetectable viremia. We characterize here the immunological disturbances associated with major CD4-lymphopenia in these two scenarios as compared to untreated viremic HIV...
Rate of increase in circulating IL7 and loss of IL7Ralpha expression differ in ...
Albuquerque, A. S.; Cortesão, C. S.; Foxall, R. B.; Victorino, R. M.; Sousa, A. E.IL-7 is a nonredundant cytokine for T cell homeostasis. Circulating IL-7 levels increase in lymphopenic clinical settings, including HIV-1 infection. HIV-2 infection is considered a “natural” model of attenuated HIV disease given its much slower rate of CD4 decline than HIV-1 and limited impact on the survival of the majority of infected adults. We compared untreated HIV-1- and HIV-2-infected patients and found...
Monocyte-mediated T cell suppression by HIV-2 envelope proteins
Cavaleiro, R.; Brunn, G. J.; Albuquerque, A. S.; Victorino, R. M.; Platt, J. L.; Sousa, A. E.HIV-2 is associated with an attenuated form of HIV disease. We investigate here the immunosuppressive effects of the HIV-2 envelope protein, gp105. We found that gp105 suppresses activation of T cells through a monocyte-mediated mechanism. Suppression of T cell activation by gp105 depends on contact between monocytes and T cells, but not on CD4+CD25+ T cells. The TLR4 pathway is likely involved, since gp105 act...