title: Short communication: Experimental toxocarosis in Chinese Kun Ming mice: Dose-dependent larval distribution and modulation of immune responses.
abstract: Toxocarosis is an important parasitic zoonosis which is mainly caused by the infective larvae of Toxocara canis. To identify whether there are correlations among the infectious dose, the larval migrans and immune modulation in inbred Chinese Kun Ming (KM) mice, experimental infections were carried out with a range of dosages of 100, 500, 1000, 2000, and 3000 embryonated eggs (EE). Pathogenic reactions were observed in terms of physical and central nervous symptoms. Distributions of T. canis larvae in liver, lung, kidney, heart and brain organs were respectively detected by scanning tissue sections. Moreover, quantitative real-time PCR was employed to identify the variations of Th2 immune response. The results showed that high inocula resulted in advanced larval emergences and arrested migrations in liver, lung, kidney and brain. However, no larvae were found in any of the histological sections of heart tissues. Higher levels of interleukin (IL)-4, IL-5, and IL-10 were detected along with the increasing inoculation doses, but the heaviest inoculum (3000 EE in this study) resulted in the sharp reduction of these ILs. Although no neurological symptoms or mortalities were noticed, these results indicated dose-dependent distribution patterns and immune regulations of T. canis larvae infection in KM mice.
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China.
authors.forename: Guangxu
authors.initials: G
authors.lastname: Ma
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China.
authors.forename: Yancai
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China.
authors.forename: Ling
authors.initials: L
authors.lastname: Hu
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China.
authors.forename: Yongfang
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China.
authors.forename: Honghong
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of Veterinary Medicine, Rongchang Campus, Southwest University, Chongqing 402460, People's Republic of China. Electronic address: rongqiongzhou@126.com.
authors.forename: Rongqiong
authors.initials: R
authors.lastname: Zhou
mesh_terms: D000818:Animals; D007113:Immunity, Innate; D007814:Larva / Q000235:genetics / Q000502:physiology; D007816:Larva Migrans, Visceral; D051379:Mice; D012376:Rodent Diseases / Q000276:immunology* / Q000469:parasitology; D017166:Toxocara canis / Q000254:growth & development / Q000502:physiology*; D014120:Toxocariasis / Q000276:immunology* / Q000469:parasitology
keywords: Chinese Kun Ming mice; Immune response; Larval distribution; Pathogenic reactions; Toxocarosis