Antigenic components of Gnathostoma spinigerum recognized by infected human sera by two-dimensional polyacrylamide gel electrophoresis and immunoblotting.

Antigenic components of Gnathostoma spinigerum larval extract were revealed by two-dimensional gel electrophoresis (2-DE) and immunoblot analysis using sera from patients with 6 proven cases of gnathostomiasis, 5 presumptive cases of gnathostomiasis, 3 proven cases of angiostrongyliasis, 3 proven cases of cysticercosis, and pooled sera from healthy adults. By the 2-DE, the larval extract was highly complex and consisted of more than 75 polypeptides. Immunoblotting analysis of this larval extract after reaction with each of 6 proven gnathostomiasis sera revealed various numbers of antigenic spots ranging from 30 to 70 spots at the approximate molecular masses of less than 14.4 to more than 94 kDa with isoelectric points (pI) of less than 4.65 to 9.6. Antigenic spots at the approximate molecular mass of more than 30 kDa were recognized with the proven angiostrongyliasis, proven cysticercosis and healthy control sera but these sera did not react with the spots at approximate molecular masses of 23-25 kDa with pI of 8.3-8.5. The reacted spots, which consisted of at least 1 to 2 spots, were unique for the recognition of gnathostomiasis sera. Five out of 6 (83.3%) proven and 4 out of 5 (80%) presumptive gnathostomiasis sera reacted with these specific spots.