title: Murine polymorphonuclear neutrophils produce interferon-gamma in response to pulmonary infection with Nocardia asteroides.
abstract: Nocardia asteroides causes an acute, necrotizing pneumonia characterized by extensive infiltration of polymorphonuclear neutrophils (PMNs) into the lungs. Although PMNs have historically been classified as end-point cells, recent investigations have indicated that PMNs have the ability to secrete cytokines such as interleukin (IL)-4 and IL-12. This study investigated the ability of PMNs to produce cytokines in a murine model of N. asteroides pulmonary infection. Flow cytometric analysis demonstrated the production of interferon-gamma (IFN-gamma), but not IL-4, by PMNs in response to this infection. IFN-gamma production correlated with peak infiltration of PMNs into the lungs. Cell sorting and enzyme-linked immunosorbent assay were used to confirm cytokine production by cells with nuclear morphology characteristic of PMNs. This is the first report of IFN-gamma production by neutrophils in response to an infection in vivo. These results suggest that PMNs play an important role in directing the host toward a T helper cell type 1 phenotypic response in the lungs.
authors.affiliation: Department of Medical Microbiology and Immunology, University of California School of Medicine, University of California, Davis, 95616, USA.
authors.forename: Terri N
authors.initials: TN
authors.lastname: Ellis
authors.forename: Blaine L
authors.initials: BL
authors.lastname: Beaman
mesh_terms: D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015870:Gene Expression; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000235:genetics; D015847:Interleukin-4 / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D009617:Nocardia Infections / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D009616:Nocardia asteroides / Q000276:immunology* / Q000302:isolation & purification; D018410:Pneumonia, Bacterial / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D013047:Specific Pathogen-Free Organisms; D013997:Time Factors
chemical_list: D015847:Interleukin-4; D007371:Interferon-gamma