Cote, C.K. and Rossi, C.A. and Kang, Angray S. and Morrow, Phillip R. and Lee, J.S. and Welkos, S.L. (2005) The detection of protective antigen (PA) associated with spores of Bacillus anthracis and the effects of anti-PA antibodies on spore germination and macrophage interactions. Microbial Pathogenesis, 38 (5-6). pp. 209-225. ISSN 0882-4010Full text not available from this repository.
The protective antigen (PA) component of the anthrax toxins is an essential virulence factor of Bacillus anthracis and is the major protective immunogen. The kinetics of PA production during growth of B. anthracis, and the roles of anti-PA antibody in host immunity are not clearly defined. Production of PA by the vegetative organisms peaks during the shift from exponential to stationary phase of growth. Recently, PA was also found to be associated with spores. In our study, PA-specific mRNA was detected in spores by RT-PCR within 15-min of exposure to germinant. PA protein was detected by immunomagnetic electrochemiluminescence (ECL) on spores within 1 h of exposure to a germination medium and was rapidly released into the supernatant. PA was not demonstrated on ungerminated spores by RNA analysis, ECL, or spore-based anti-PA ELISA; however, it was detected on ungerminated spores by immunoelectron microscopy (immunoem). In rabbits, PA induces polyclonal antibodies (Abs) that, in addition to their anti-toxin neutralizing activities, exhibit anti-spore activities. In this study, the anti-spore effects of a human monoclonal Ab specific for PA (AVP-hPA mAb, Avanir Pharmaceuticals) were characterized. AVP-hPA mAb retarded germination in vitro, and enhanced the phagocytic and sporicidal activities of macrophages. The activities were comparable to those of the polyclonal rabbit anti-rPA Ab. Assays to detect germination inhibitory activity (GIA) in serum from vaccinated mice and guinea pigs suggested a possible role for anti-PA Abs in protection. Thus, anti-PA Ab-mediated, anti-spore activities may play a role in protection during the early stages of an anthrax infection.
|Additional Information:||Online ISSN 1096-1208|
|Uncontrolled Keywords:||Anthrax, Bacillus anthracis, Spores, Protective antigen, Anti-PA antibodies, Immunity|
|Subjects:||University of Westminster > Science and Technology > Life Sciences, School of (No longer in use)|
|Depositing User:||Miss Nina Watts|
|Date Deposited:||23 May 2006|
|Last Modified:||10 Apr 2008 13:41|
Actions (login required)
|Edit Item (Repository staff only)|