Alveolar macrophages from sheep naturally infected by visna-maedi virus contribute to IL-8 production in the lung.
Sheep naturally infected by visna-maedi virus often develop a chronic interstitial lung disease characterized by an alveolitis comprising lymphocytes, neutrophils and macrophages. The alpha chemokine interleukin-8 (IL-8) was detected in cell free bronchoalveolar lavage fluid from naturally infected animals, confirmed by RT-PCR, presenting typical lesions of maedi and elevated total alveolar cell counts. No detectable IL-8 was found in the fluid obtained from uninfected animals. IL-8 concentration in alveolar fluid is correlated with alveolar neutrophil counts. Bronchoalveolar lavage cells from infected animals were found to contain a large amount of IL-8 mRNA and may contribute to IL-8 production. In situ hybridization showed that macrophages were the predominant cell type expressing IL-8 mRNA. Sustained production of IL-8 by alveolar macrophages during visna-maedi infection could suffice for neutrophil attraction to the alveoli, and may contribute to the development of lesions.
Legastelois
I
I
Laboratoire d'Immunologie et de Biologie Pulmonaire, Université Claude Bernard, Hôpital Louis Pradel, Lyon, France.
Cottin
V
V
Mornex
J F
JF
Cordier
G
G
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002452:Cell Count; D005260:Female; D017403:In Situ Hybridization / Q000662:veterinary; D016209:Interleukin-8 / Q000096:biosynthesis*; D007958:Leukocyte Count; D008168:Lung / Q000378:metabolism*; D016676:Macrophages, Alveolar / Q000378:metabolism* / Q000473:pathology; D008297:Male; D011021:Pneumonia, Progressive Interstitial, of Sheep / Q000378:metabolism* / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012333:RNA, Messenger / Q000378:metabolism; D012756:Sheep; D014790:Visna-maedi virus
D016209:Interleukin-8; D012333:RNA, Messenger