Development of Lateral Flow Immunochromatographic Assay with Anti-Pythium insidiosum Antibodies for Point-of-Care Testing of Vascular Pythiosis

Abstract The pathogenic oomycete Pythium insidiosum causes a fatal infectious illness known as pythiosis, impacting humans and certain animals in numerous countries in the tropics and subtropics. Delayed diagnosis is a primary factor contributing to the heightened morbidity and mortality associated with the disease. Several new serodiagnostic methods have been developed to improve the identification of pythiosis. However, these assays provide only indirect evidence of pythiosis and are not readily available in the commercial market. Here, we have developed an affordable point-of-care test (POCT) kit based on an immunochromatographic assay for the direct detection of P. insidiosum antigens. Our recent findings reveal that the lateral flow sandwich immunological testing cassette can accurately identify vascular pythiosis antigens using a small volume of patient’s plasma, accomplishing 100% accuracy and a limit of detection (LOD) of 8 ng/mL. This prototype cartridge represents a significant stride toward the advancement of enriched POCT for pythiosis serodiagnosis.