Development of cattle TB vaccines based on heterologous prime-boosting strategies

AbstractDevelopment of a TB vaccine for cattle is a research priority in Great Britain. Two challenges need to be addressed. Firstly, vaccine strategies enhancing the efficacy of M. bovis bacille Calmette Guérin (BCG), currently the only potentially available TB vaccine, and secondly the development of a diagnostic test to be used alongside vaccination to differentiate vaccinated and infected animals (DIVA test). Significant progress in developing TB vaccines for cattle has been made over the last 7 years. Specifically: (i) DNA, protein, or viral subunit subunit vaccines used in combination with BCG have been shown to give superior protection against experimental challenge in cattle than BCG (heterologous prime-boost), (ii) neonatal BCG vaccination provides protection, (iii) prototype reagents that allow discrimination between vaccinated and infected animals have been developed; and (iv) and correlates of disease severity have been identified that can predict the success or failure of vaccination. The present overview provides details of some of these advances. [Ethiop.J.Health Dev. 2008;22(Special Issue):100-104

A comparative study on the epidemiology and immuno-pathology of bovine tuberculosis in Bos indicus and Bos taurus cattle in Ethiopia

AbstractBovine tuberculosis is a disease of dual effect, having public health and economic implications. The present study was conducted on its epidemiology and immuno-pathology in Holstein and Zebu breeds of cattle. Skin test, post mortem examination and pathology scoring, bacteriology, whole blood gamma interferon assay, ELISPOT assay, and lateral flow assay were used. An overall prevalence of 13.5% (n=5,424) was recorded; both prevalence (2 =61.8; P<0.001) and severity of pathology (mean pathology scores + SEM: 6.84±0.79 vs. 5.21±0.30; P=0.018, Mann-Whitney test) were significantly higher in Holstein than in Zebu. Similarly, IFN- responses to avian PPD (0.490.10 vs. 0.390.07), bovine PPD (0.630.11 vs. 0.430.07), or the ESAT6-CFP10 protein cocktail (0.430.01 vs. 0.300.05) were significantly higher (for all antigens: p<0.02) in Holstein than in Zebu cattle. However, both Holstein and Zebu exhibited similar T cell and antibody responses to different mycobacterial antigens i.e. no repertoire difference was observed between the two breeds. Thus, the present study showed increased susceptibility of Holsteins to bovine TB as compared to Zebu, similarity between Holsteins and Zebus in their antigen responses, and a positive correlation between IFN- responses and severity of pathology of bovine TB. [Ethiop.J.Health Dev. 2008;22(Special Issue):132-134