title: Cellular infiltration at skin lesions and draining lymph nodes of sheep infested with adult Hyalomma anatolicum anatolicum ticks.
abstract: Immunohistochemical analysis of skin and draining lymph nodes of sheep repeatedly infested with the ixodid tick Hyalomma anatolicum anatolicum were studied for different antigen-presenting cells and lymphocyte subpopulations. Infiltration of neutrophils, macrophages and lymphocytes adjacent to the tick bite site were observed. Skin biopsies showed significant increases in dermal infiltration of CD8+ and gammadelta+ T cells at 72 h and 8 days after both primary and secondary infestation. Infiltrations of MHC-II DR/DQ decreased at 72 h after tick infestation, whereas significant increases were recorded for 8-day skin biopsies. CD1+ cellular infiltrations were observed during secondary infestations at the dermis. Decreased ratios of CD4:CD8 T cells and MHC-II:CD1 antigen-presenting cells were observed in both infestations compared to healthy skin biopsies. Ratios of alphabeta:gammadelta T cells increased gradually during infestation compared to uninfested skin. The regional lymph nodes from tick-infested sheep showed an increased CD8+, gammadelta+ T and CD1+ cellular infiltration compared to control lymph nodes. CD4+ T cells were decreased. There were no significant changes in CD45R+ cellular infiltration either at skin lesions or regional lymph nodes.
authors.affiliation: Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai 500 007, India. dboppana@yahoo.com
authors.forename: D K V
authors.initials: DK
authors.lastname: Boppana
authors.forename: S K
authors.initials: SK
authors.lastname: Wikel
authors.forename: D G
authors.initials: DG
authors.lastname: Raj
authors.forename: M B
authors.initials: MB
authors.lastname: Manohar
authors.forename: J
authors.initials: J
authors.lastname: Lalitha
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D026863:Ixodidae / Q000502:physiology*; D008198:Lymph Nodes / Q000469:parasitology*; D008297:Male; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology / Q000469:parasitology*; D012867:Skin / Q000469:parasitology* / Q000473:pathology*; D013984:Tick Infestations / Q000276:immunology / Q000469:parasitology* / Q000662:veterinary*