title: Characterisation of lesional infiltrates of dendritic cells and T cell subtypes during primary infestation of sheep with Psoroptes ovis, the sheep scab mite.
abstract: Earlier studies of cattle and sheep have demonstrated that Psoroptes ovis infestations provoke an intense immunoinflammatory response dominated by eosinophils accompanied by a substantial infiltrate of lymphocytes. However, the kinetics of the lymphocyte response and the subtypes involved have not been characterised. We employed two groups of sheep to investigate the early (1-21 days) and later (21-63 days) infiltration of lymphocyte subpopulations and dendritic cells in primary infestations of sheep with P. ovis. Immunohistochemistry indicated that by 4 days after infestation numbers of CD4+ and CD45RA+ cells in lesional skin had increased significantly (P<0.03 and P<0.005, respectively) and that a significant increase in gammadelta T cells and dendritic cells (CD1b+) had occurred by 8 days (P<0.02 and P<0.01, respectively). Numbers of lymphocyte and dendritic cells declined from 49 to 63 days after infestation. Our observations suggest that mite-derived products exert a profound influence on the early recruitment of lymphocytes that may significantly influence the genesis of the adaptive immune response.
authors.affiliation: Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Easter Bush, Roslin EH25 9RG, UK. Adri.vandenBroek@ed.ac.uk
authors.forename: A H M
authors.initials: AH
authors.lastname: van den Broek
authors.forename: J F
authors.initials: JF
authors.lastname: Huntley
authors.forename: A
authors.initials: A
authors.lastname: Mackellar
authors.forename: J
authors.initials: J
authors.lastname: Machell
authors.forename: M A
authors.initials: MA
authors.lastname: Taylor
authors.forename: H R P
authors.initials: HR
authors.lastname: Miller
mesh_terms: D000818:Animals; D001706:Biopsy / Q000662:veterinary; D003713:Dendritic Cells / Q000276:immunology* / Q000469:parasitology; D007150:Immunohistochemistry / Q000662:veterinary; D018655:Lymphocyte Count / Q000662:veterinary; D008924:Mite Infestations / Q000276:immunology* / Q000469:parasitology; D040042:Psoroptidae / Q000276:immunology*; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology* / Q000469:parasitology*; D012876:Skin Diseases, Parasitic / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000469:parasitology; D013601:T-Lymphocytes / Q000276:immunology / Q000469:parasitology