title: Efficacy of a recombinant trypsin product against bovine herpesvirus 1 associated with in vivo- and in vitro-derived bovine embryos.
abstract: Although porcine-origin trypsin will effectively remove bovine herpesvirus 1 (BHV-1) associated with in vivo-derived embryos, TrypLE, a recombinant trypsin-like protease, has not been evaluated. In Experiment 1, 17 groups of 10 in vivo-derived embryos were exposed to BHV-1, treated with TrypLE Express or TrypLE Select (10x concentration) for varying intervals, and assayed as 2 groups of 5 embryos. TrypLE Select treatment for 5 and 10 min (two and seven groups of five embryos, respectively) effectively inactivated BHV-1. In Experiment 2, 22 groups of 10 IVF embryos were treated and assayed. Treatment with TrypLE Select for 7 and 10 min (six groups of five embryos each) and with TrypLE Select diluted 1:2 for 10 min (seven groups of five embryos) was also effective. In Experiment 3, 17 groups of 10 IVF embryos were further evaluated with TrypLE Select undiluted and diluted 1:2 for 10 min. Treatment with the diluted product was effective (18 groups of five embryos), whereas the undiluted product was not completely effective (virus isolated from 2 of 16 groups). In Experiment 4, IVF embryos were treated as described in Experiment 3 and then cultured individually or as groups of five on uterine tubal cells (UTCs) for 48 h; 60% of UTC samples associated with groups of embryos and 35% of UTC associated with individual embryo samples were positive for BHV-1. Therefore, although TrypLE Select appeared to have promise for the treatment of in vivo-derived embryos, it cannot be recommended for treatment of in vitro-derived embryos.
authors.affiliation: Department of Pathobiology, College of Veterinary Medicine, 126 Sugg Laboratory, Auburn University, AL 36849, USA.
authors.forename: M S D
authors.initials: MS
authors.lastname: Marley
authors.forename: M D
authors.initials: MD
authors.lastname: Givens
authors.forename: P K
authors.initials: PK
authors.lastname: Galik
authors.forename: K P
authors.initials: KP
authors.lastname: Riddell
authors.forename: C R
authors.initials: CR
authors.lastname: Looney
authors.forename: D A
authors.initials: DA
authors.lastname: Stringfellow
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D002417:Cattle / Q000196:embryology*; D002418:Cattle Diseases / Q000517:prevention & control / Q000635:transmission / Q000821:virology*; D004624:Embryo Transfer / Q000662:veterinary; D004622:Embryo, Mammalian / Q000821:virology*; D005307:Fertilization in Vitro / Q000662:veterinary; D006566:Herpesviridae Infections / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary; D007242:Herpesvirus 1, Bovine / Q000187:drug effects*; D011994:Recombinant Proteins; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D000998:Antiviral Agents; D011994:Recombinant Proteins; D014357:Trypsin