title: T cell-dependent elimination of dividing Trypanosoma grosi from the bloodstream of Mongolian jirds.
abstract: Mongolian jirds, Meriones unguiculatus, are susceptible to infection with Trypanosoma grosi, which naturally parasitizes Apodemus spp. The present study investigated T cell dependence of elimination of T. grosi from the bloodstream of jirds by in vivo T cell depletion using a monoclonal antibody (HUSM-M.g.15). In T cell-depleted jirds, elimination of T. grosi, particularly the dividing forms, from the bloodstream was significantly delayed, occurring at around week 3 p.i. The kinetics of serum levels of IgM and IgG specific to trypanosomes in T cell-depleted and control immunocompetent jirds were different; peak levels of IgM were noted on days 6-8 p.i. around the time of peak parasitaemia (day 6 p.i.) in immunocompetent jirds, whereas the serum levels began to increase abruptly after day 10 p.i., peaking at around day 18 p.i. in T cell-depleted jirds. Similarly, serum IgG increased after day 6 p.i. in immunocompetent jirds, in contrast to after day 12 p.i. in T cell-depleted jirds, and the level increased steadily even after disappearance of parasitaemia. Our findings indicate that T cells play a major role at least in the 'first crisis' during elimination of dividing T. grosi from the bloodstream.
authors.affiliation: Department of Parasitology, Hirosaki University School of Medicine, Hirosaki 036-8562, Japan. sato7dp4@cc.hirosaki-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Ishita
authors.forename: A
authors.initials: A
authors.lastname: Osanai
authors.forename: M
authors.initials: M
authors.lastname: Yagisawa
authors.forename: H
authors.initials: H
authors.lastname: Kamiya
authors.forename: M
authors.initials: M
authors.lastname: Ito
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000913:Antibodies, Protozoan / Q000097:blood; D005260:Female; D005849:Gerbillinae; D016867:Immunocompromised Host / Q000276:immunology; D007150:Immunohistochemistry / Q000662:veterinary; D007700:Kinetics; D008212:Lymphocyte Depletion / Q000662:veterinary; D018512:Parasitemia / Q000276:immunology / Q000469:parasitology / Q000662:veterinary; D012376:Rodent Diseases / Q000097:blood / Q000276:immunology* / Q000469:parasitology*; D013601:T-Lymphocytes / Q000276:immunology* / Q000469:parasitology; D014345:Trypanosoma / Q000276:immunology*; D014352:Trypanosomiasis / Q000097:blood / Q000276:immunology* / Q000469:parasitology / Q000662:veterinary*
chemical_list: D000911:Antibodies, Monoclonal; D000913:Antibodies, Protozoan