Jauro Solomon, Ndumnego Okechukwu C, Ellis Charlotte, Buys Angela, Beyer Wolfgang, Heerden Henriette van
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa.
Department of Veterinary Microbiology, Faculty of Veterinary Medicine, University of Maiduguri, Maiduguri 600230, Nigeria.
Pathogens. 2020 Jul 10;9(7):557. doi: 10.3390/pathogens9070557.
The Sterne live spore vaccine (SLSV, strain 34F2) is the veterinary vaccine of choice against anthrax though contra-indicated for use with antimicrobials. However, the use of non-living anthrax vaccine (NLAV) candidates can overcome the SLSV limitation. In this study, cattle were vaccinated with either of the NLAV (purified recombinant PA (PrPA) or crude rPA (CrPA) and formaldehyde-inactivated spores (FIS of strain 34F2) and emulsigen-D/alhydrogel adjuvants) or SLSV. The immunogenicity of the NLAV and SLSV was assessed and the protective efficacies evaluated using a passive immunization mouse model. Polyclonal IgG (including the IgG1 subset) and IgM responses increased significantly across all vaccination groups after the first vaccination. Individual IgG subsets titres peaked significantly with all vaccines used after the second vaccination at week 5 and remained significant at week 12 when compared to week 0. The toxin neutralization (TNA) titres of the NLAV vaccinated cattle groups showed similar trends to those observed with the ELISA titres, except that the former were lower, but still significant, when compared to week 0. The opsonophagocytic assay indicated good antibody opsonizing responses with 75% (PrPA+FIS), 66% (CrPA+FIS) and 80% (SLSV) phagocytosis following spores opsonization. In the passive protection test, A/J mice transfused with purified IgG from cattle vaccinated with PrPA+FIS+Emulsigen-D/Alhydrogel and SLSV had 73% and 75% protection from challenge with strain 34F2 spores, respectively, whereas IgG from cattle vaccinated with CrPA+FIS+Emulsigen-D/Alhydrogel offered insignificant protection of 20%. There was no difference in protective immune response in cattle vaccinated twice with either the PrPA+FIS or SLSV. Moreover, PrPA+FIS did not show any residual side effects in vaccinated cattle. These results suggest that the immunogenicity and protective efficacy induced by the NLAV (PrPA+FIS) in the cattle and passive mouse protection test, respectively, are comparable to that induced by the standard SLSV.
斯特恩活芽孢疫苗（SLSV，34F2菌株）是预防炭疽的首选兽用疫苗，不过与抗菌药物联用时为禁忌。然而，使用非活性炭疽疫苗（NLAV）候选疫苗可以克服SLSV的局限性。在本研究中，给牛接种了以下疫苗之一：NLAV（纯化重组保护性抗原（PrPA）或粗制rPA（CrPA）以及甲醛灭活芽孢（34F2菌株的FIS）和乳化剂-D/氢氧化铝佐剂）或SLSV。评估了NLAV和SLSV的免疫原性，并使用被动免疫小鼠模型评估了保护效力。首次接种后，所有疫苗接种组的多克隆IgG（包括IgG1亚群）和IgM反应均显著增加。第二次接种后第5周，所有使用的疫苗的个体IgG亚群滴度均显著达到峰值，与第0周相比，在第12周时仍保持显著水平。NLAV接种牛组的毒素中和（TNA）滴度显示出与ELISA滴度相似的趋势，只是前者较低，但与第0周相比仍具有显著性。调理吞噬试验表明，芽孢调理后，PrPA+FIS组、CrPA+FIS组和SLSV组的吞噬率分别为75%、66%和80%，显示出良好的抗体调理反应。在被动保护试验中，输注来自接种PrPA+FIS+乳化剂-D/氢氧化铝和SLSV的牛的纯化IgG的A/J小鼠，分别有73%和75%的保护率免受34F2菌株芽孢攻击，而来自接种CrPA+FIS+乳化剂-D/氢氧化铝的牛的IgG提供的保护率为20%，无显著意义。用PrPA+FIS或SLSV对牛进行两次接种后的保护性免疫反应没有差异。此外，PrPA+FIS在接种牛中未显示任何残留副作用。这些结果表明，NLAV（PrPA+FIS）在牛中诱导的免疫原性和在被动小鼠保护试验中诱导的保护效力分别与标准SLSV诱导的相当。
