02629nas a2200301   4500000000100000008004100001260003000042653002500072653002000097653002600117653003100143653001200174100001500186700002200201700001400223700001800237700001400255700001200269700001400281700001900295700001500314700001200329245011300341856008000454300000900534520177000543022001402313       2026                            d  c02/2026bACS Publications10aMycobacterium leprae10aContact Tracing10aDiagnostic techniques10aEpidemiological Monitoring10aleprosy1 ade Jesus A1 aArreguin-Campos R1 aMyndrul V1 ade Oliveira A1 aMenezes C1 aBueno L1 aEersels K1 avan Grinsven B1 aFujiwara R1 aCleij T00aDetection of Anti- Antibodies in Leprosy Contacts Using a Label-Free Approach with the Heat-Transfer Method.  uhttps://pubs.acs.org/doi/pdf/10.1021/acssensors.5c04885?ref=article_openPDF  a1-113 a<p>Early detection of Mycobacterium leprae infection is essential to interrupt leprosy transmission and guide prophylactic interventions. Current diagnostic strategies rely largely on clinical signs, and laboratory tools lack sensitivity to detect asymptomatic individuals, who can play a critical role in disease transmission and evolve to disease as well. In this study, we report the development of a heat-transfer method (HTM)-based biosensor employing a newly designed multiepitope protein receptor, capable of detecting anti-M. leprae antibodies in human serum, with sensitivity for leprosy contacts. The protein, initially tested in ELISA assays, was then immobilized on aluminum chips, and its successful attachment and functionality were confirmed using FTIR, EDX, ELISA-like, and confocal fluorescence assays. Evaluation of the sensor was performed using an HTM transducing platform, where thermal measurements revealed a clear response to antibody binding that is serum dilution-dependent as it is in established methods such as ELISA. The biosensor distinguished serum from M. leprae-exposed individuals from that of non-exposed controls and a tuberculosis sample, with effect sizes up to four times higher. Notably, responses were comparable to the ones obtained using ELISA at similar serum dilution. These findings demonstrate, for the first time, the feasibility of using a thermal biosensing platform to detect specific antibodies in a clinically relevant scenario, paving the way for a sensitive, low-cost, and point-of-care tool for early leprosy detection and contact surveillance. This strategy addresses the critical challenge of identifying M. leprae exposure and holds potential for broader application in infectious disease diagnostics.</p>  a2379-3694