Supaporn Nuamtanongสุภาพร น่วมทะนงParon Dekumyoyพารณ ดีคำย้อยPoom Adisakwattanaภูมิ อดิศักดิ์วัฒนาMahidol University. Faculty of Tropical Medicine. Department of Helminthology2015-07-062021-08-172015-07-062021-08-172015-07-062014https://repository.li.mahidol.ac.th/handle/123456789/63165Joint International Tropical Medicine Meeting 2014: 3D perspectives on tropical medicine: drivers, diversity and determination the 8th seminar on food-and water-borne parasitic zoonoses: 2-4 December 2014: Centara Grand Bangkok Convention Center at Central World, Bangkok, Thailand. Bangkok: Faculty of Tropical Medicine, Mahidol University; 2014. p. 248.Gnathostoma spinigerum infection is a serious health problem occurring in several countries, including Thailand. The gold standard for diagnosis is currently detection of antibody- specific 24 kDa antigens with immunoblotting. However, this technique requires lengthy antigen preparation, and experience to interpret correctly. In this study, recombinant antigen, cathepsin L (GsCatL), of G.spinigerum was evaluated as an immunodiagnostic tool. Several previous studies suggested cathepsin L as a potential antigen for the diagnosis of helminthic infections. Initially, GsCatLcDNA was cloned into a prokaryotic expression vector and then expressed as recombinant GsCatL (rGsCatL) in Escherichia coli. The rGsCatL expressed at the molecular size of 48 kDa was purified and evaluated with gnathostomiasis-, other helminthic infected-and healthy sera using immunoblot and indirect ELISA. The results showed that rGsCatL cross-reacted with all sera by immunoblot with lowsensitivity (25.7%) and specificity (41%). The indirect ELISA also exhibited the same result as immunoblotting. These results suggest that rGsCatLusing a prokaryotic expression system is not suitable for diagnosis of gnathostomiasis. However, a eukaryotic expression system still needs to be verified for correct conformational structure through further evaluation.engMahidol UniversityGnathostoma spinigerumCathepsin LImmunoblotIndirect ELISAProceeding Poster