Browsing by Author "Belmonte, Liliana"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    HIV enteropathy: HAART reduces HIV-induced stem cell hyperproliferation and crypt hypertrophy to normal in jejunal mucosa
    (2013) Batman, Paul A.; Kapembwa, Martin S.; Belmonte, Liliana; Tudor, Gerald; Kotler, Donald P.; Potten, Christopher S.; Booth, Catherine; Cahn, Pedro; Griffin, Geoffrey E.
    Objective: To analyse the structural and kinetic response of small intestinal crypt epithelial cells including stem cells to highly active antiretroviral therapy (HAART). Design: Crypt size and proliferative activity of transit and stem cells in jejunal mucosa were quantified using morphometric techniques. Methods: Crypt length was measured by counting the number of enterocytes along one side of a number of crypts in each biopsy specimen and the mean crypt length was calculated. Proliferating crypt cells were identified with MIB-1 monoclonal antibody, and the percentage of crypt cells in proliferation was calculated at each cell position along the length of the crypt (proliferation index). Data were obtained from 9 HIV-positive test patients co-infected with microsporidia, 34 HIV-positive patients receiving HAART and 13 control cases. Results: Crypt length was significantly greater in test patients than in controls, but crypt length in patients receiving HAART was normal. The proliferation index was greater in test subjects than in controls in stem and transit cell compartments, and was decreased in patients treated with HAART only in the stem cell region of the crypt. Conclusions: Villous atrophy in HIV enteropathy is attributed to crypt hypertrophy and encroachment of crypt cells onto villi. HAART restores normal crypt structure by inhibition of HIV-driven stem cell hyperproliferation at the crypt bases.
  • Thumbnail Image
    Item
    Macrophage HIV-1 infection in duodenal tissue of patients on long term HAART
    (2010) Zalar, Alberto; Figueroa, Maria Ines; Ruibal-Ares, Beatriz; Baré, Patricia; Cahn, Pedro; Bracco, Maria Marta; Belmonte, Liliana
    Mucosal surfaces play a major role in human immunodeficiency virus type 1 (HIV-1) transmission and pathogenesis. Since the role of intestinal macrophages as viral reservoirs during chronic HIV-1 infection has not been elucidated, we investigated the effects of successful therapy on intestinal HIV-1 persistence. Intestinal macrophage infection was demonstrated by the expression of p24 antigen by flow cytometry and by the presence of proviral DNA, assessed by PCR. Proviral DNA was detected in duodenal mucosa of HIV-infected patients under treatment with undetectable plasma viral load. These findings confirm that intestinal macrophages can act as viral reservoirs and permit HIV-1 production even after viral suppression following antiretroviral therapy.
  • Thumbnail Image
    Item
    The intestinal mucosa as a reservoir of HIV-1 infection after successful HAART
    (2007-10-01) Belmonte, Liliana; Olmos, Martin; Fanin, Ana; Parodi, Cecilia; Baré, Patricia; Concetti, Hugo; Pérez, Héctor; de Bracco, Maria Marta E; Cahn, Pedro
    The presence of HIV-1 RNA in distal duodenal mucosa was evaluated in 44 HIV-1-positive patients. HIV-1 RNA was detected in gut tissue in antiretroviral-naive patients with high plasma viral loads, as well as in patients on HAART with plasma viral loads below the limit of detection and in patients on HAART with virological failure. The intestinal mucosa seems to serve as a reservoir poorly influenced by levels of plasma viral load or HAART.