title: T cytotoxic-1 CD8+ T cells are effector cells against pneumocystis in mice.
abstract: Host defenses are profoundly compromised in HIV-infected hosts due to progressive depletion of CD4+ T lymphocytes. A hallmark of HIV infection is Pneumocystis carinii (PC) pneumonia. Recently, CD8+ T cells, which are recruited to the lung in large numbers in response to PC infection, have been associated with some level of host defense as well as contributing to lung injury in BALB/c mice. In this study, we show that CD8+ T cells that have a T cytotoxic-1 response to PC in BALB/c mice, as determined by secretion of IFN-gamma, have in vitro killing activity against PC and effect clearance of the organism in adoptive transfer studies. Moreover, non-T cytotoxic-1 CD8+ T cells lacked in vitro effector activity and contributed to lung injury upon adoptive transfer. This dichotomous response in CD8+ T cell response may in part explain the clinical heterogeneity in the severity of PC pneumonia.
authors.affiliation: Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh, 3705 Fifth Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Florencia
authors.initials: F
authors.lastname: McAllister
authors.forename: Florencia
authors.initials: F
authors.lastname: Mc Allister
authors.forename: Chad
authors.initials: C
authors.lastname: Steele
authors.forename: Mingquan
authors.initials: M
authors.lastname: Zheng
authors.forename: Erana
authors.initials: E
authors.lastname: Young
authors.forename: Judd E
authors.initials: JE
authors.lastname: Shellito
authors.forename: Luis
authors.initials: L
authors.lastname: Marrero
authors.forename: Jay K
authors.initials: JK
authors.lastname: Kolls
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D054357:Chemokine CXCL10; D054370:Chemokine CXCL9; D019743:Chemokines, CXC / Q000096:biosynthesis; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic; D005822:Genetic Vectors; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis; D007371:Interferon-gamma / Q000008:administration & dosage / Q000235:genetics / Q000493:pharmacokinetics; D008168:Lung / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D008212:Lymphocyte Depletion; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016513:Mice, SCID; D020556:Neutrophil Infiltration / Q000235:genetics / Q000276:immunology; D045363:Pneumocystis carinii / Q000254:growth & development / Q000276:immunology*; D011020:Pneumonia, Pneumocystis / Q000276:immunology* / Q000382:microbiology* / Q000473:pathology / Q000821:virology; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine / Q000096:biosynthesis; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000382:microbiology / Q000821:virology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000276:immunology* / Q000382:microbiology
chemical_list: C080810:CXCL9 protein, human; C515187:CXCR3 protein, human; D054357:Chemokine CXCL10; D054370:Chemokine CXCL9; D019743:Chemokines, CXC; C515188:Cxcr3 protein, mouse; D036341:Intercellular Signaling Peptides and Proteins; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine; D007371:Interferon-gamma