ABSTRACT
Background: Synthetic biology is emerging as a viable alternative for the production of recombinant antigens for diagnostic applications. It offers a safe alternative for the synthesis of antigenic principles derived from organisms that pose a high biological risk. Methods: Here, we describe an enzyme-linked immunosorbent assay (ELISA) using the synthetic recombinant LipL32 (rLipL32) protein expressed in Escherichia coli for the detection of Leptospira-specific antibodies in human serum samples. The rLipL32-based ELISA was compared with a microscopic agglutination test (MAT), which is currently used as the gold standard for the diagnosis of leptospirosis. Results: Our results showed that all the MAT-positive serum samples were positive for Leptospira-specific IgG in an ELISA, while 65% (n = 13) of these samples were also positive for Leptospira-specific IgM. In the MAT-negative serum samples, 80% and 55% of the samples were detected as negative by an ELISA for Leptospira-specific IgM and IgG, respectively. Conclusion: An ELISA using the synthetic rLipL32 antigen was able to distinguish Leptospira-specific IgM (sensitivity 65% and specificity 80%) and IgG (sensitivity 100% and specificity 55%) in human serum samples and has the potential to serve as a rapid diagnostic test for leptospirosis.
ABSTRACT
Objective: The aim of this article was to review published research articles on leptospirosis, in particular the recent incidence of leptospirosis in Malaysia and the currently available diagnostic methods for the detection of leptospirosis. Methods: PubMed, Google Scholar and Google Search databases were searched using the key words Leptospira and leptospirosis. A total of seventy-six references were reviewed including sixty-seven research articles, three annual reports from Ministry of Health and six online newspaper articles. This review includes the following five sub-headings: introduction, leptospirosis transmission, leptospirosis incidents, laboratory diagnosis of leptospirosis and treatment and prevention of leptospirosis. Results: An increase in incidents of leptospirosis cases has been seen in recent years in Malaysia. The recent floods have contributed to the rise in the number of reported cases. Current diagnostic approaches such as dark field microscopy, microscopic agglutination test (MAT), Polymerase chain reaction and serological tests are inadequate as the organism is a slow grower. Conclusion: There is an urgent need to develop newer techniques for rapid detection of leptospirosis. The combination of PCR and ELISA are suggested for rapid and accurate diagnosis of leptospirosis. Studies on the mechanism of pathogenesis of Leptospira are needed for the development of vaccines that are safe for human use.