Serodiagnosis of wildlife leptospirosis employing recombinant leptospiral immunoglobulin like b protein antigen

Abstract

Leptospirosis is a major threat in tropical and subtropical countries as well as temperate countries. The disease is caused by pathogenic Leptospira species and considered to be an emerging or re-emerging disease in many countries of the world. Infection in domestic animals and wildlife can lead to economic loss and pose a potential spread to the communities. In the present study recombinant LigB protein is employed in latex agglutination test, which is a cross reacting lipoprotein able to detect acute infection caused by any pathogenic leptospiral serovars. It was employed for serodiagnosis of leptospirosis. The 46KDa 6X His tagged LigB protein, obtained by IPTG induction of recombinant E. coli M15 cells containing the N-terminal region of LigB gee in P QE30 expression vector, was purified by Ni-NTA affinity chromatography and adsorbed on latex bead surface for performing latex agglutination test against Leptospirosis suspected wildlife field sera. A total of  80 wildlife sera samples were collected, including  27 wild feline sera samples (18 tigers, 8 lions, and 1 jaguar) obtained from Chhatbir zoo, Chandigarh, 42 serasamples ( 8 tigers, 4 lions and 6 leopards, 2 cheethals, 1 black buck, 12 buffaloes and  9 zoo staff) sera and 3 live rodents ) were received  from Jodhpur zoo Rajasthan, 8 sera samples (4 tigers, 3 leopards, 1 lion) sera from Van Vihar National park, Bohpal, Madhya Pradesh and 3 sera samples (2 lions,and 1 tiger) received from Biwani Mini zoo, Haryana, India. The result showed that sera were tested positive by rLigB based LAT, which were reconfirmed using microscopic agglutination test (MAT). The results from LAT were in concordance with MAT. In conclusion, rLigB based LAT is a rapid, pen site, reliable diagnostic tool of high sensitivity and specificity, under laboratory and field conditions, for the detection of Leptospirosis .