title: Mechanisms of eosinophilia in mice infested with larval Haemaphysalis longicornis ticks.
abstract: Infestation of larval Haemaphysalis longicornis ticks induced a threefold increase of eosinophils in the peripheral blood of normal WBB6F1- +/+ mice 2 days after tick infestation. In genetically mast cell-deficient WBB6F1- W/Wv mice, a threefold increase of blood eosinophils was observed 6 days after the tick infestation. However, marked infiltration of eosinophils was detected in the tick infestation sites of the WBB6F1- +/+ mice but not the WBB6F1- W/Wv mice. When the mast cell deficiency of WBB6F1- W/Wv mice had been rescued locally by intradermal injections of WBB6F1- +/+ mouse-derived cultured mast cells, a rapid increase of blood eosinophils and tissue infiltration of eosinophils were revealed following tick infestation. The intravenous (i.v.) injection of immune spleen or lymph node cells obtained from WBB6F1- +/+ mice 10 days after tick infestation led to significant eosinophilia in naive recipient mice. Treatment with anti-Thy-1.2 or anti-CD4 monoclonal antibody (mAb) and complement (C) completely abolished the eosinophilia; the early response (2 days after tick challenge) is dependent on mast cells at the feeding site, and the late response (6 days after tick challenge) is dependent on T lymphocytes. Since amplified interleukin-5 (IL-5) cDNA was detectable in the spleen cells 4 days after tick infestation, the late response might be mediated by IL-5. The infiltration of eosinophils at the feeding site of skin appeared to be dependent on mast cells.
authors.affiliation: Department of Veterinary Surgery, College of Agriculture, University of Osaka Prefecture, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ushio
authors.forename: S
authors.initials: S
authors.lastname: Hirota
authors.forename: T
authors.initials: T
authors.lastname: Jippo
authors.forename: S
authors.initials: S
authors.lastname: Higuchi
authors.forename: K
authors.initials: K
authors.lastname: Kawamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Kitamura
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004802:Eosinophilia / Q000276:immunology*; D016219:Immunotherapy, Adoptive; D007377:Interleukin-3 / Q000096:biosynthesis; D015848:Interleukin-5 / Q000096:biosynthesis; D008198:Lymph Nodes / Q000276:immunology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D011043:Pokeweed Mitogens / Q000276:immunology; D016133:Polymerase Chain Reaction; D012867:Skin / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013984:Tick Infestations / Q000276:immunology*
chemical_list: D017077:Culture Media, Conditioned; D007377:Interleukin-3; D015848:Interleukin-5; D011043:Pokeweed Mitogens