title: Bacteria-induced egg hatching differs for Trichuris muris and Trichuris suis.
abstract: BACKGROUND
  Eggs of the porcine whipworm Trichuris suis are currently explored in human clinical trials as a treatment of immune-mediated diseases. In this context, only the infective, embryonated eggs, constitute the Active Pharmaceutical Ingredient (API). The rodent whipworm, Trichuris muris is commonly used as a laboratory model to study Trichuris biology. The embryonated eggs (containing a fully developed larva) are biologically active and will invade the large intestinal mucosa of the host. This study aims to assess the in vitro hatching of T. muris and T. suis eggs in various bacterial cultures as a measure for their biological activity.
  
  
  METHODS
  Eggs of T. muris and T. suis were incubated with Escherichia coli strain (BL-21) at three concentrations in a slightly modified in vitro egg hatching assay previously developed for T. muris. Additionally, E. coli strains (M15, SG13009, PMC103, JM109, TUNER, DH5alpha, TOP10) and five Gram-positive bacteria (Enterococcus caccae, Streptococcus hyointestinalis, Lactobacillus amylovorus, L. murinus, and L. reuteri) were tested as a hatching stimulus for T. muris and T. suis eggs.
  
  
  RESULTS
  Whereas T. muris eggs hatched, T. suis did not, even when exposed to different concentrations and strains of E. coli after 4 and 24-hour incubation. When incubated with Gram-positive bacteria, only T. muris eggs showed noticeable hatching after 20 h, although with high variability.
  
  
  CONCLUSIONS
  The observed difference in hatching of T. muris and T. suis eggs incubated with selected bacteria, indicate significant biological differences which may reflect specific adaptation to different host-specific gut microbiota.
authors.affiliation: Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark. nerminav@plen.ku.dk.
authors.forename: Nermina
authors.initials: N
authors.lastname: Vejzagić
authors.affiliation: Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. Roberto.Adelfio@unibas.ch.|University of Basel, Basel, Switzerland. Roberto.Adelfio@unibas.ch.
authors.forename: Roberto
authors.initials: R
authors.lastname: Adelfio
authors.affiliation: Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. Jennifer.Keiser@unibas.ch.|University of Basel, Basel, Switzerland. Jennifer.Keiser@unibas.ch.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Keiser
authors.affiliation: Parasite Technologies A/S, Hørsholm, Denmark. hek@para-tech.dk.
authors.forename: Helene
authors.initials: H
authors.lastname: Kringel
authors.affiliation: Parasite Technologies A/S, Hørsholm, Denmark. smt@sund.ku.dk.|Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark. smt@sund.ku.dk.
authors.forename: Stig Milan
authors.initials: SM
authors.lastname: Thamsborg
authors.affiliation: Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark. chk@plen.ku.dk.|Parasite Technologies A/S, Hørsholm, Denmark. chk@plen.ku.dk.
authors.forename: Christian M O
authors.initials: CM
authors.lastname: Kapel
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000502:physiology*; D006094:Gram-Positive Bacteria / Q000502:physiology*; D010063:Ovum / Q000382:microbiology* / Q000502:physiology*; D013045:Species Specificity; D014258:Trichuris / Q000382:microbiology* / Q000502:physiology*