title: The impact of active HIV-1 replication on the physiological age-related decline of immature-transitional B-cells in HIV-1 infected children.
abstract: OBJECTIVE
  To characterize the level of immature-transitional B-cells in blood during pediatric HIV-1 infection in relation to active or suppressed viremia. We also aimed at characterizing the level of expression of CXCR4, CXCR5 and CCR7 on immature-transitional B-cells, as these receptors are important mediators for homing of B-cells.
  
  
  METHODS
  Forty-eight HIV-1 vertically infected children (33 viral controllers and 15 viremic patients) and 33 age-matched healthy controls were enrolled in a cross-sectional study.
  
  
  METHODS
  We measured the levels of peripheral immature-transitional B-cells in all groups in relation to switched memory B-cells by flow cytometry. In parallel we evaluated CXCR4, CXCR5 and CCR7 expression on immature-transitional B-cells and measured plasma levels of CXCL12, BAFF and interleukin-7 by ELISA.
  
  
  RESULTS
  We observed a lack of physiological age-related decline of immature-transitional B-cells in viremic children in parallel to a decreased level of switched memory B-cells. Interestingly, immature-transitional B-cells from viremic children presented with high levels of CXCR4. On the contrary, the level of CXCL12, the natural ligand for CXCR4, was lowest in the HIV-1 infected group, as compared with controls.
  
  
  CONCLUSIONS
  Control of HIV-1 viremia through antiretroviral treatment appears to be crucial in decreasing the expansion and alteration of immature-transitional B-cells.
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Immunology, Karolinska University Hospital Huddinge, Stockholm, Sweden. Alberto.Cagigi@ki.se
authors.forename: Alberto
authors.initials: A
authors.lastname: Cagigi
authors.forename: Paolo
authors.initials: P
authors.lastname: Palma
authors.forename: Anna
authors.initials: A
authors.lastname: Nilsson
authors.forename: Silvia
authors.initials: S
authors.lastname: Di Cesare
authors.forename: Simone
authors.initials: S
authors.lastname: Pensieroso
authors.forename: Maria
authors.initials: M
authors.lastname: Kakoulidou
authors.forename: Stefania
authors.initials: S
authors.lastname: Bernardi
authors.forename: Paolo
authors.initials: P
authors.lastname: Rossi
authors.forename: Francesca
authors.initials: F
authors.lastname: Chiodi
mesh_terms: D023241:Antiretroviral Therapy, Highly Active; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D008297:Male; D054448:Precursor Cells, B-Lymphoid / Q000378:metabolism*; D019718:Receptors, CXCR4 / Q000276:immunology*; D014766:Viremia
chemical_list: D019718:Receptors, CXCR4