Evaluation of New ELISA based on rLsa63 - rLipL32 antigens for serodiagnosis of Human Leptospirosis

Timely diagnosis of leptospirosis is essential for an effective treatment. Large diversity of clinical symptoms has led leptospirosis diagnosis difficult. Researchers have conducted many tests with wide-range of sensitivity and specificity to achieve novel diagnostic procedures which have higher sensitivity and specificity compared with previous tests and which are more reliable and available to public laboratories. This study aimed to introduce Lsa63 and LipL32 proteins-based ELISA tests with more sensitivity, specificity, accuracy and convenience for public laboratories. Recombinant forms of Lsa63 and LipL32 proteins were first generated. After coating these proteins, IgM and IgG ELISA tests were performed. 220 patients with suspicion of leptospirosis infection were selected for serum collection. The sera tests were carried out using MAT, IgM and IgG ELISA tests. In order to assess the performance of ELISA, the results of this test were compared with MAT. 30% of serum samples (n=65) in MAT were positive for leptospirosis infection, while ELISA tests including rLipL32- rLsa63-IgM and rLipL32-rLsa63-IgG showed 40.45% (n=89) and 38.63% (n=80) positive reaction respectively. Our results demonstrated that new ELISA tests based on mixing LipL32 and Lsa63 proteins, a novel mixture of recombinant antigens, are valuable to detect specific antibodies against pathogenic Leptospira in human serum and could be considered as helpful techniques in leptospirosis diagnosis.