title: Relationship between CD38 expression on peripheral blood T-cells and monocytes, and response to antiretroviral therapy: a one-year longitudinal study of a cohort of chronically infected ART-naive HIV-1+ patients.
abstract: BACKGROUND
  HIV-1 infection has been associated with high expression of CD38 on peripheral blood (PB) CD8+ and CD4+ T-cells, which has been related with poor prognosis in untreated HIV-1+ patients. In turn, CD38 expression on PB monocytes from HIV-1+ individuals and its behavior after starting antiretroviral therapy (ART) have been poorly studied.
  
  
  METHODS
  CD38 expression on PB CD8+ and CD4+ T-lymphocytes and monocytes was prospectively analyzed in 30 ART-naive HIV-1+ patients, using a quantitative multiparameter flow cytometry approach. Patients were tested prior to therapy, and at weeks +2, +4, +8, +12, and +52 after ART.
  
  
  RESULTS
  Prior to ART, CD38 expression was significantly increased on PB CD8+ and CD4+ T-cells and monocytes; despite a significant decrease after ART, CD38 expression remained abnormally high on PB CD8+ T-cells and monocytes, even after one year of therapy, in the absence of detectable plasma viral load. The ART-induced early changes on CD38 expression by PB T-cells and monocytes differed among the cell subsets analyzed and patient groups, probably reflecting an interaction between the direct effects of therapy and a redistribution of the PB compartments of T-cells and monocytes. Hierarchical clustering analysis showed that the overall pattern of changes in CD38 expression observed early after starting ART was predictive of a better response to therapy, not only for PB CD8+ T-cells, but also for CD4+ T-cells and monocytes. Accordingly, those HIV-1+ patients, who experienced a more pronounced increase in CD38 expression on both PB CD4+ T-cells and monocytes after 2 weeks of ART, showed a more rapid viral clearance, which might reflect decreased HIV-1 replication in lymph nodes and other tissues, and a partial restoration of hematopoiesis.
  
  
  CONCLUSIONS
  Combined quantitative measurement of CD38 expression on PB monocytes, and CD8+ and CD4+ T-cells is a more useful tool for monitoring HIV-1+ patients under ART, rather than quantitation of CD38 expression on PB CD8+ T-lymphocytes alone.
authors.affiliation: Service of Flow Cytometry, Center for Cancer Research, University of Salamanca, Salamanca, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Almeida
authors.forename: Miguel
authors.initials: M
authors.lastname: Cordero
authors.forename: Julia
authors.initials: J
authors.lastname: Almeida
authors.forename: Alberto
authors.initials: A
authors.lastname: Orfao
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000276:immunology*; D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology / Q000821:virology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology / Q000821:virology; D016000:Cluster Analysis; D005260:Female; D015658:HIV Infections / Q000628:therapy* / Q000821:virology; D015497:HIV-1 / Q000472:pathogenicity*; D006801:Humans; D016130:Immunophenotyping; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D018448:Models, Immunological; D009000:Monocytes / Q000276:immunology* / Q000473:pathology / Q000821:virology; D011237:Predictive Value of Tests; D012367:RNA, Viral / Q000097:blood; D019562:Viral Load
chemical_list: D012367:RNA, Viral; D051997:ADP-ribosyl Cyclase 1