title: Rapid induction of IgE responses to a worm cysteine protease during murine pre-patent schistosome infection.
abstract: BACKGROUND
  During the pre-patent stage of infection, juvenile Schistosoma blood flukes co-opt signals from the adaptive immune system to facilitate parasite development, but the types of responses that are induced at this early stage of infection, and the parasite antigens they target, have not been characterized.
  
  
  RESULTS
  Through analysis of experimental pre-patent infections, we show that the S. mansoni cysteine protease SmCB1 is rapidly targeted by an antigen-specific IgE response. The induction of this response is independent of schistosome eggs as infection with male or female worms alone also induced SmCB1-specific IgE. We also show that the SmCB1-specific IgE response is dependent on cognate CD4+ T cell help and IL-4, suggesting that pre-patent Th2 responses provide T cell help for the SmCB1-specific IgE response. Finally, exposed human subjects also produced IgE against SmCB1.
  
  
  CONCLUSIONS
  Our data demonstrate that, like eggs, schistosome worms also induce functional type 2 responses and that a parasite cysteine protease is an inducer of type 2 responses during the early stages of schistosome infection.
authors.affiliation: Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
authors.forename: Lucia A
authors.initials: LA
authors.lastname: de Oliveira Fraga
authors.forename: Erika W
authors.initials: EW
authors.lastname: Lamb
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Moreno
authors.forename: Mitali
authors.initials: M
authors.lastname: Chatterjee
authors.forename: Jan
authors.initials: J
authors.lastname: Dvořák
authors.forename: Melaine
authors.initials: M
authors.lastname: Delcroix
authors.forename: Mohammed
authors.initials: M
authors.lastname: Sajid
authors.forename: Conor R
authors.initials: CR
authors.lastname: Caffrey
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Davies
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D002401:Cathepsin B / Q000276:immunology / Q000378:metabolism*; D005260:Female; D015801:Helminth Proteins / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D015847:Interleukin-4 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008018:Life Cycle Stages; D008297:Male; D051379:Mice; D012550:Schistosoma mansoni / Q000276:immunology* / Q000472:pathogenicity; D012552:Schistosomiasis / Q000097:blood / Q000276:immunology*; D058408:Th1-Th2 Balance; D018418:Th2 Cells / Q000276:immunology*
chemical_list: D015801:Helminth Proteins; D015847:Interleukin-4; D007073:Immunoglobulin E; C466432:CB2 protein, Schistosoma mansoni; D002401:Cathepsin B