title: Induction of acute pleural inflammation by Staphylococcus aureus. I. CD4+ T cells play a critical role in experimental empyema.
abstract: Bacterial empyema is a frequent complication of pneumonia in patients with acquired immunodeficiency syndrome (AIDS). A model of Staphylococcus aureus empyema was developed that closely resembles bacterial empyema in patients infected with human immunodeficiency virus (HIV). Results show a compartmentalized chemokine response in bacterial empyema. The chemokine levels were higher in the pleural compartment than in the peripheral circulation. Polymorphonuclear leukocyte counts, murine GRO-alpha (KC), and macrophage inflammatory protein-2 levels were significantly (P<.001) lower in CD4+ knockout (CD4 KO) mice pleural fluid than in CD4+ wild-type (CD4 WT) mice. The CD4 KO mice had poorer bacterial clearance than CD4 WT mice. During S. aureus infection, interleukin-10 levels increased in the CD4 KO mice, whereas interferon-gamma levels were increased in CD4 WT mice. CD4+ T cell depletion results in a decreased pleural chemokine response, decreased neutrophil influx into pleural space, and impaired bacterial clearance in empyema.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, Veterans Affairs Medical Center, Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: K A
authors.initials: KA
authors.lastname: Mohammed
authors.forename: N
authors.initials: N
authors.lastname: Nasreen
authors.forename: M J
authors.initials: MJ
authors.lastname: Ward
authors.forename: V B
authors.initials: VB
authors.lastname: Antony
mesh_terms: D000818:Animals; D015704:CD4 Antigens / Q000235:genetics / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D054360:Chemokine CXCL1; D054426:Chemokine CXCL2; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000032:analysis; D016724:Empyema, Pleural / Q000276:immunology* / Q000382:microbiology; D005260:Female; D006133:Growth Substances / Q000032:analysis; D015658:HIV Infections / Q000150:complications; D006801:Humans; D007249:Inflammation; D036341:Intercellular Signaling Peptides and Proteins; D007958:Leukocyte Count; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D015846:Monokines / Q000032:analysis; D009504:Neutrophils / Q000502:physiology; D013203:Staphylococcal Infections / Q000276:immunology*; D013211:Staphylococcus aureus; D013997:Time Factors
chemical_list: D015704:CD4 Antigens; C475829:CXCL1 protein, human; D054360:Chemokine CXCL1; D054426:Chemokine CXCL2; D019743:Chemokines, CXC; D002630:Chemotactic Factors; C475895:Cxcl1 protein, mouse; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D015846:Monokines