title: Expulsion of the gastrointestinal cestode, Hymenolepis diminuta by tolerant rats: evidence for mediation by a Th2 type immune enhanced goblet cell hyperplasia, increased mucin production and secretion.
abstract: The processes underlying expulsion of Hymenolepis diminuta in rats are not known. Expression levels of mRNAs of several cytokines revealed a Th2 response that differed between worm infection levels. IL-4 protein levels decreased while IL-13 levels increased in a 50-worm infection by 30 dpi; the converse was seen with a five-worm infection. A negative correlation was found between IL-4 or IL-13 mRNA expression and worm biomass, between IL-13 protein levels and worm number or worm biomass, and between IL-4 protein levels and worm biomass in 50-worm infections. A negative correlation between IL-4 mRNA or protein expression and worm biomass was observed with five-worm infections. A strong correlation between Muc2 mRNA expression and decreased worm number or biomass in a 50-worm infection was observed. Muc2 protein, goblet cell numbers and mucin decreased in a 50-worm infection by 20 days post-infection. These changes were not seen with five-worm infections where worms are not expelled. The data show that rats infected with 50 H. diminuta mount a Th2 response leading to high levels of IL-13, increased goblet cell numbers and increased mucin2 production and release. The mucus traps the worms, which are progressively expelled from the small intestine.
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada. raw@yorku.ca
authors.forename: R A
authors.initials: RA
authors.lastname: Webb
authors.forename: T
authors.initials: T
authors.lastname: Hoque
authors.forename: S
authors.initials: S
authors.lastname: Dimas
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D020397:Goblet Cells / Q000469:parasitology* / Q000473:pathology; D006925:Hymenolepiasis / Q000276:immunology*; D006926:Hymenolepis / Q000276:immunology*; D006965:Hyperplasia; D007422:Intestines / Q000276:immunology; D009077:Mucins / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D050800:STAT6 Transcription Factor; D018418:Th2 Cells / Q000276:immunology* / Q000469:parasitology
chemical_list: D009077:Mucins; D012333:RNA, Messenger; D050800:STAT6 Transcription Factor; C494100:Stat6 protein, mouse