Development of a recombinant construct as an immunogenic target for leptospirosis using LipL41 and molecular adjuvants

Introduction: Leptospirosis, an infectious disease that can spread from animals to humans, requires the development of a safe and effective vaccine. The immunogenic characteristics of LipL41, a conserved outer membrane protein of Leptospira, have been identified as a promising vaccine candidate. In this study, a recombinant DNA construct, pTR-EGFP-LipL41, incorporating the LipL41 gene and hGMCSF adjuvant in the pTR600 vector with a cytomegalovirus (CMV) promoter, was designed and evaluated. Methods: The Chinese hamster ovary (CHO) cell line was transfected with pTR-EGFP-LipL41 and pTR-EGFP-hGMCSF-LipL41 using Lipofectamine 2000, and fluorescence microscopy analyzed their expression. Results: The expression analysis demonstrated successful expression of pTR-EGFP-LipL41 and pTR-EGFP-hGMCSF-LipL41 in CHO cells. In vitro analysis of cell lines further assessed the expression of chemokines and cytokines, and molecular docking analyses were conducted to investigate interactions between various adjuvants (hGMCSF, hIgGFc, and hC3d) and LipL41. Docking studies uncovered key interactions between LipL41 and other adjuvants. The constructed recombinant DNA and molecular adjuvants exhibited a robust immunogenic response. Conclusion: Further evaluation in suitable animal models may establish its effectiveness as a productive and safe immunogenic molecule against leptospiral infection.