Immunologic responses of bison to vaccination with Brucella abortus strain RB51: Comparison of parenteral to ballistic delivery via compressed pellets or photopolymerized hydrogels

Immune Responses and Efficacy of Brucella Abortus Strain RB51 in Bison After Delivery in a Dry Dart Formulation or by Parenteral Inoculation

“…At 4, 8, 13, 16, 21, and 24 wks after initial vaccination, and 12, 15, 22, and 27 weeks after booster vaccination, blood was obtained from the jugular vein of all bison and placed into an acid-citrate dextrose solution. Peripheral blood mononuclear cells (PBMC) were enriched by density centrifugation (Sigma Diagnostics, Inc., St. Louis, MO, USA) and adjusted to 110 7 viable cells per ml in RPMI as determined by trypan blue dye exclusion.…”

“…As a vaccination program to reduce disease prevalence in bison would require a long-term commitment and significant economic costs, maximizing the efficacy of the planned vaccine is essential. Although a remotely delivered vaccine would be required for delivery to free-ranging bison, vaccine formulation and delivery method may influence immune responses and efficacy (7). In the current study, we evaluated a novel dry dart formulation which incorporates B. abortus strain RB51 vaccine (RB51) in a delivery form amiable to remote delivery options.…”

Live RB51 vaccine lyophilized hydrogel formulations with increased shelf life for practical ballistic delivery

“…Irgacure 184 was chosen as a photoinitiator due to its known cytocompatability with mammalian cell types and previous effective use in photopolymerizing RB51 loaded hydrogels Nuttelman et al, 2004). Photopolymerization of analogous PEG (non-degrading) diacrylates to form rigid 3-dimensional gel matrices in aqueous milieu is well-documented, known to be biologically benign when encapsulating live mammalian cells and bacteria, and therefore well-suited for this application (Olsen et al, 2006;Hubbell et al, 1993;Poshusta and Anseth, 2001;Lyman et al, 1996;Bryant and Anseth, 2001;Itle and Pishko, 2005;Liu and Bhatia, 2002;Sawhney et al, 1993).…”

“…We have previously described cross-linked degradable PEG hydrogels as a live-vaccine carrier when photopolymerized directly into the payload chamber of HPC biobullets (Olsen et al, 2006;Christie et al, 2006). As precedent, analogous PEG hydrogels utilizing mild processing conditions are biologically benign and have been used to encapsulate a variety of live cells Working et al, 1997;Poshusta and Anseth, 2001;Lyman et al, 1996;Bryant and Anseth, 2001;Itle and Pishko, 2005;Liu and Bhatia, 2002;Nuttelman et al, 2004).…”

“…As precedent, analogous PEG hydrogels utilizing mild processing conditions are biologically benign and have been used to encapsulate a variety of live cells Working et al, 1997;Poshusta and Anseth, 2001;Lyman et al, 1996;Bryant and Anseth, 2001;Itle and Pishko, 2005;Liu and Bhatia, 2002;Nuttelman et al, 2004). High dosing and dose viability of both live PEG-encapsulated RB51 and model live Pseudomonas aeruginosa bacteria were shown (Olsen et al, 2006;Christie et al, 2006). Preliminary serological tests in penned bison indicate that an immune response is generated against vaccinated viable RB51 organisms when administered ballistically using wet PEG hydrogels, but overall actual efficacy must be determined by reduced abortion rates when vaccinated pregnant female animals are challenged with B. abortus.…”