tailieunhanh - Báo cáo khoa học: "Mac-1-mediated Uptake and Killing of Bordetella bronchiseptica by Porcine Alveolar Macrophages"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Mac-1-mediated Uptake and Killing of Bordetella bronchiseptica by Porcine Alveolar Macrophages | J. Vet. Sci. 2003 4 1 41-49 JOURNAL OF Veterinary Science Mac-1-mediated Uptake and Killing of Bordetella bronchiseptica by Porcine Alveolar Macrophages Jong-keuk Lee Lawrence B. Schook1 and Mark S. Rutherford1 National Genome Research Institute National Institute of Health 5 Nokbun-dong Eunpyung-ku Seoul 122-701 Korea Department of Animal Sciences University of Illinois 1201 W. Gregory Dr. Urbana IL 61801 USA Department of Veterinary PathoBiology University of Minnesota 1988 Fitch Ave. St. Paul MN 55108 USA Received August 14 2002 Accepted March 7 2003 Abstract The role of Mac-1 as a receptor for Bordetella bronchiseptica infection of alveolar macrophages AM p was examined using 6 strains 2 ATCC and 4 pathogenic field isolates to assess B. bronchiseptica binding uptake and replication in prim ary porcine AM . All B. bronchiseptica strains were rapidly kille d by porcine serum in a dose- and time-dependent m anner. How ever heat-inactivated porcine serum HIS did not demonstrate any bacterial-killing activity suggesting that complement may have a direct killin g activity. All field isolate s were more resistant to direct com plem ent-mediated B. bronchiseptica killin g. The uptake of B. bronchiseptica into AM w as inhibited approximately 50 by antiMac-1 monoclonal antibodies in the m edium. How ever B. bronchiseptica phagocytosed in the presence of serum or HIS was not altered by anti-Mac-1 antibodies although more bacteria were internalized by addition of serum or HIS. These data suggest that Mac-1 is a target for direct uptake of B. bronchiseptica via opsoninindependent binding. The phagocytosed B. bronchise-ptica either via direct or serum-mediated binding were efficiently kille d by AM w ithin 10 hr postinfection. This dem onstrates that Mac-1-mediated B. bronchiseptica uptake is a bacterial killin g pathw ay not leading to productive infections in AM . Key words Mac-1 Bordetella bronchiseptica alveolar macrophage pig Introduction Bordetella bronchiseptica is an