Development of Hyperimmune Equine Plasma to Virulence Associated Protein A (VapA) of Rhodococcus equi
نویسندگان
چکیده
Procedure – A proprietary formulation of ATCC 33701 Rhodococcus equi known to contain the virulence plasmid was developed and tested on 72 horses. Antibody levels to Rhodococcus equi Virulence associated protein A (VapA) were determined relative to a Standard Plasma. A clinical trial was performed on 28 foals. Seven foals were administered hyperimmune plasma and seven foals were administered purified equine immunoglobulin specific for VapA and VapC one day prior to intrabronchial challenge with Rhodococcus equi strain 103+. Eleven foals were challenged with no prior treatment and three foals received no challenge or treatment. A quantitative anti-VapA antibody enzyme immunoassay (EIA) was developed by using known concentrations of purified antiVapA antibodies to create a standard curve.
منابع مشابه
Survival of foals with experimentally induced Rhodococcus equi infection given either hyperimmune plasma containing R. equi antibody or normal equine plasma.
The purpose of this study was to determine if colostrum-deprived foals with experimentally induced Rhodococcus equi pneumonia have a decreased severity of the disease and decreased mortality rate when given hyperimmune (HI) R. equi antibody plasma (R. equi titer at least 100 % and virulence-associated protein A [VapA] at least 10000) prophylactically versus when given normal equine plasma (R. e...
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Rhodococcus equi is a facultative intracellular bacterium that can escape from bactericidal mechanisms associated with phagocytosis. Virulence-associated protein A (VapA), encoded on a virulence-associated plasmid, is essential for intracellular survival in macrophages, but its function is not known. Here, we show that the extracellular addition of recombinant glutathione S-transferase (GST)-Va...
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