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Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins
Published on: July 1, 2011
Diagnostic efficacy of lsa63 antigen for human leptospirosis
Safar Ali Alizadeh1, Seyyed Saeed Eshraghi1, Mohammad Reza Pourmand1
1Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran.
Insights
A new enzyme-linked immunosorbent assay (ELISA) using the recombinant leptospiral surface adhesion (Lsa63) protein shows promise for diagnosing leptospirosis. This novel diagnostic test offers high sensitivity and specificity for detecting Leptospira infections.
Area of Science:
- * Infectious disease diagnostics
- * Microbiology and immunology
- * Recombinant protein technology
Background:
- * Accurate leptospirosis diagnosis is crucial for effective treatment due to its varied differential diagnoses.
- * Leptospiral researchers are developing novel serological methods using recombinant antigens to enhance diagnostic accuracy.
- * Existing serological tests for leptospirosis diagnosis have limitations, necessitating improved diagnostic tools.
Purpose of the Study:
- * To develop a new diagnostic test for leptospirosis by creating an enzyme-linked immunosorbent assay (ELISA) utilizing the novel recombinant leptospiral surface adhesion (Lsa63) protein.
- * To evaluate the performance of the developed Lsa63-based ELISA in detecting both IgM and IgG antibodies against Leptospira.
- * To compare the efficacy of the Lsa63-ELISAs with the established microscopic agglutination test (MAT) as a gold standard.
Main Methods:
- * Recombinant Lsa63 (rLsa63) protein was produced in Escherichia coli (E. coli).
- * IgM and IgG enzyme-linked immunosorbent assays (ELISAs) were developed using the rLsa63 antigen.
- * The performance of the Lsa63-ELISAs was assessed using 220 human serum samples from individuals suspected of leptospirosis and compared against the microscopic agglutination test (MAT).
Main Results:
- * Among 220 serum samples, 30% were positive by MAT, while 38% and 40.9% were positive by IgG and IgM rLsa63-ELISA, respectively.
- * The IgM-Lsa63-ELISA demonstrated a sensitivity of 93.8%, specificity of 81.29%, and accuracy of 85.0%.
- * The IgG-Lsa63-ELISA showed a sensitivity of 83.07%, specificity of 80.64%, and accuracy of 81.36%.
Conclusions:
- * The developed Lsa63-ELISAs exhibit promising sensitivity and specificity for the detection of Leptospira serovars.
- * These findings suggest that Lsa63-based ELISA is a viable new tool for leptospirosis diagnosis.
- * Further validation of Lsa63-ELISAs could lead to improved diagnostic strategies for leptospirosis.
Background:
Timely diagnosis of leptospirosis is essential for early and effective treatment, for there are many differential diagnoses for it.. Leptospiral researchers have an increasing interest in developing new serological methods with recombinant antigens to improve the Leptospirosis diagnosis. Several serological tests have been developed for the proper diagnosis of leptospirosis.
Objectives:
To improve the previous works we developed an enzyme linked immunosorbent assay (ELISA) with novel recombinant leptospiral surface adhesion (Lsa63) protein to offer a new test.
Materials And Methods:
In an experimental study, Recombinant Lsa63 (rLsa63) was produced in Escherishia coli (E.coli) BL21 (DE3). By using rLsa63, we generated IgM and IgG ELISA. Performance of these tests was compared to microscopic agglutination golden test (MAT). Two hundred twenty human serum samples were obtained from individuals suspicious of leptospirosis who were referred to Guilan Province Central Leptospira Laboratory for definitive diagnosis. The sensitivity, specificity and other statistical indexes of Lsa63-ELISAs were also determined.
Results:
Among 220 serum samples, 30% (n = 65) had positive MAT responses, and also 38% (n = 84) and 40.9% (n = 90) showed positive reaction to IgG and IgM rLsa63-ELISA, respectively. The sensitivity, specificity and accuracy were 93.8%, 81.29 % and 85.0 for IgM-Lsa63- ELISA and 83.07, 80, 64 and 81.36 for IgG-Lsa63- ELISA, respectively.
Conclusions:
Our results demonstrated that the sensitivity and specificity of Lsa63-ELISAs are promising for the detection of Leptospira serovars.
