title: CD4+ CCR5+ and CD4+ CCR3+ lymphocyte subset and monocyte apoptosis in patients with acute visceral leishmaniasis.
abstract: The potential involvement of apoptosis in the pathogenesis of visceral leishmaniasis (VL) was examined by studying spontaneous and Leishmania antigen (LAg)-induced apoptosis using cryopreserved peripheral blood mononuclear cells (PBMC) of Sicilian patients with VL. Results indicate that monocytes and T lymphocytes from acute VL patients show a significantly higher level of apoptosis compared with that observed in healed subjects. The percentage of apoptotic cells was higher in monocytes than in T lymphocytes. T cells involved in programmed cell death (PCD) were mainly of the CD4(+) phenotype. In particular, the T helper 1-type (Th1) subset, as evaluated by chemokine receptor-5 (CCR5) expression, is involved in this process. Cell death in Th1-type uses a CD95-mediated mechanism. Furthermore, Th1-type CCR5(+) cells are prone to cell suicide in an autocrine or paracrine way, as attested by enhanced expression of CD95L in acute VL patients. The reduction in Th1-type cells by apoptosis was confirmed by the decrease in interferon-gamma secretion. In conclusion, apoptosis of monocytes, CD4(+) and CD4(+) CCR5(+) T cells could be involved in the failure of cell mediated immunity that is responsible for severe immune-depression in VL.
authors.affiliation: Department of BioPathology and BioMedical Methodologies, University of Palermo, Palermo, Italy.
authors.forename: Marcella
authors.initials: M
authors.lastname: Potestio
authors.forename: Pietro
authors.initials: P
authors.lastname: D'Agostino
authors.forename: Giuseppina Colonna
authors.initials: GC
authors.lastname: Romano
authors.forename: Salvatore
authors.initials: S
authors.lastname: Milano
authors.forename: Viviana
authors.initials: V
authors.lastname: Ferlazzo
authors.forename: Alessandra
authors.initials: A
authors.lastname: Aquino
authors.forename: Gloria
authors.initials: G
authors.lastname: Di Bella
authors.forename: Rosalba
authors.initials: R
authors.lastname: Caruso
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Gambino
authors.forename: Giustina
authors.initials: G
authors.lastname: Vitale
authors.forename: Serafino
authors.initials: S
authors.lastname: Mansueto
authors.forename: Enrico
authors.initials: E
authors.lastname: Cillari
mesh_terms: D000208:Acute Disease; D000328:Adult; D000953:Antigens, Protozoan / Q000276:immunology; D017209:Apoptosis / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D007898:Leishmaniasis, Visceral / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology*; D009000:Monocytes / Q000276:immunology*; D054397:Receptors, CCR3; D019713:Receptors, CCR5 / Q000276:immunology; D019707:Receptors, Chemokine / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D019014:fas Receptor / Q000276:immunology
chemical_list: D000953:Antigens, Protozoan; C515350:CCR3 protein, human; D054397:Receptors, CCR3; D019713:Receptors, CCR5; D019707:Receptors, Chemokine; D019014:fas Receptor