Generation of Monoclonal Antibodies Against Recombinant Capsular Antigen of Burkholderia mallei and Its Potential Application in Glanders Disease Diagnosis

Abstract

Glanders is primarily a disease of solipeds, most mammals have a certain degree of susceptibility and infection has been reported in goats, sheep, camels, cats, dogs and various other carnivores, human cases of glanders have rarely been reported. Glanders was eradicated in many countries through the use of the mallein test and also with the application of countermeasures like intensive blood testing, rigorous culling of positive animals and strict trading restrictions but sporadic cases still occur in Asia, Africa, the Middle East, and South America. The similarities that exist between Burkholderia mallei causative agent of Glanders and its closely related bacterial species Burkholderia pseudomallei, the causative agent of melioidosis are well documented. Due to its high homology and sharing of many antigens, serological and immunological tests developed for these agents are cross-reactive. In the present study, efforts were made for the development of specific monoclonal antibodies specific to a 14 kDa recombinant capsular protein of B. mallei that does not cross-react to B. pseudomallei. For this purpose genes of 14 kDa recombinant capsular protein of B.mallei was cloned and expressed in pQE expression system. After fusion 114 hybrids were screened for reactivity and 15 were found reactive and out of which 8 were stabilized and preserved. The specificity of the antibodies was checked with different bacterial strains and the isotypes of all the clones were determined. One clone was specifically reactive to B. mallei and 2 were reactive to B. mallei and B. pseudomallei and 5 clones were crossreactive. These specific monoclonal antibodies will be helpful in the standardization of antigen detection system for Glanders.