title: In vivo activation of chicken macrophages by infectious bursal disease virus.
abstract: Infectious bursal disease virus (IBDV) infects and replicates in the dividing B lymphocytes of chickens. In the present study, the in vivo effect of IBDV infection on chicken macrophage populations and macrophage activation were examined. Specific-pathogen-free chickens were exposed to virulent IBDV and splenic macrophages were recovered during the acute phase of the disease. At 3 and 5 days post-infection (dpi), spleens of virus-exposed chickens had fewer macrophages than those of virus-free controls (p < 0.05). Confocal microscopic examination revealed cells that were positive for both KUL01 (macrophage surface marker) and R63 (IBDVVP2), indicating presence of the virus in macrophages. MQ-NCSU cells, an avian macrophage cell line, were susceptible to replication of IBDV. In addition, splenic macrophages were activated and had temporarily increased levels of mRNA transcripts of pro-inflammatory mediators, including IL-1beta, IL-6, IL-18, and iNOS. The robust expression of proinflammatory cytokine transcripts, along with a decrease in macrophage numbers, suggest that IBDV activates and may lead to a reduction of resident macrophages in vivo.
authors.affiliation: Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Palmquist
authors.forename: M
authors.initials: M
authors.lastname: Khatri
authors.forename: R M
authors.initials: RM
authors.lastname: Cha
authors.forename: B M
authors.initials: BM
authors.lastname: Goddeeris
authors.forename: B
authors.initials: B
authors.lastname: Walcheck
authors.forename: J M
authors.initials: JM
authors.lastname: Sharma
mesh_terms: D000818:Animals; D018175:Birnaviridae Infections / Q000662:veterinary* / Q000821:virology; D002460:Cell Line; D002645:Chickens / Q000821:virology*; D016207:Cytokines / Q000378:metabolism; D007243:Infectious bursal disease virus / Q000276:immunology / Q000472:pathogenicity*; D008262:Macrophage Activation / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D018613:Microscopy, Confocal; D009569:Nitric Oxide / Q000096:biosynthesis; D010587:Phagocytosis; D011201:Poultry Diseases / Q000821:virology*; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D016207:Cytokines; D009569:Nitric Oxide