title: Temperature dependent embryonic development of Trichuris suis eggs in a medicinal raw material.
abstract: The therapeutic potential of infective pig whipworm eggs, Trichuris suis ova (TSO), is currently tested in several clinical trials on immune-mediated diseases. This paper studied the embryonic development of TSO in a medicinal raw product, where the parasite eggs were suspended in sulphuric acid (pH1). Unembryonated T. suis egg batches were stored at 5, 10, 15, 20, 25, 30, and 40°C (±1°C) and examined at 2, 4, 8, and 14 weeks. Subsequently, sub-batches from each temperature were allowed to embryonate for additional 14 weeks at 25°C, and selected samples were tested for infectivity in Göttingen minipigs. Both male and female pigs were used to evaluate eventual gender specific infectivity. Storage at 30°C up to 14 weeks and subsequent embryonation for 14 weeks at 25°C did not significantly reduce the overall larval establishment in minipigs, as compared to storage at 5°C and subsequent embryonation at 25°C. As marked impairment of egg development was observed during storage at 40°C, a second set of unembryonated egg batches were incubated at 30, 32, 34, 36, 38, and 40°C (±1°C) for 1-8 weeks. The development of the eggs was repeatedly examined by manual light microscopy, multispectral analysis (OvaSpec), and an egg hatching assay prior to the final testing in minipigs (Trial 1). These methods showed that the development started earlier at higher temperatures, but the long-term storage at higher temperature affected the egg development. The present study further documents tolerance of the TSO to storage at temperature 5-15°C, at which temperature development of larvae is not initiated.
authors.affiliation: Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark. Electronic address: nerminav@plen.ku.dk.
authors.forename: Nermina
authors.initials: N
authors.lastname: Vejzagić
authors.affiliation: Parasite Technologies A/S, Dr. Neergaards Vej 3, 2970, Hørsholm, Denmark.
authors.forename: Helene
authors.initials: H
authors.lastname: Kringel
authors.affiliation: Parasite Technologies A/S, Dr. Neergaards Vej 3, 2970, Hørsholm, Denmark.
authors.forename: Johan Musaeus
authors.initials: JM
authors.lastname: Bruun
authors.affiliation: Parasite Technologies A/S, Dr. Neergaards Vej 3, 2970, Hørsholm, Denmark.
authors.forename: Allan
authors.initials: A
authors.lastname: Roepstorff
authors.affiliation: Parasite Technologies A/S, Dr. Neergaards Vej 3, 2970, Hørsholm, Denmark; Section for Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 100, 1870, Frederiksberg C, Denmark.
authors.forename: Stig Milan
authors.initials: SM
authors.lastname: Thamsborg
authors.affiliation: Ellegaard Göttingen Minipigs, Sorø Landevej 302, 4261, Dalmose, Denmark.
authors.forename: Anette Blak
authors.initials: AB
authors.lastname: Grossi
authors.affiliation: Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark; Parasite Technologies A/S, Dr. Neergaards Vej 3, 2970, Hørsholm, Denmark.
authors.forename: Christian M O
authors.initials: CM
authors.lastname: Kapel
mesh_terms: D000818:Animals; D005260:Female; D007814:Larva / Q000254:growth & development; D008297:Male; D010063:Ovum / Q000502:physiology*; D013696:Temperature; D014258:Trichuris / Q000196:embryology*
keywords: Egg development; Embryonation; Göttingen minipigs; Stability-indicating assays; Temperature; Trichuris suis ova