Recent advances in basic and applied science for the control of taeniasis/cysticercosis in Asia.

Detection of seven specific bands by immunoblot (IB) using glycoproteins (GPs) purified by lentil-lectin affinity chromatography has been the gold-standard for neurocysticercosis (NCC) serodiagnosis since 1989. However, due to the presence of contaminants, it was impossible to apply the GPs to ELISA. Our group at Asahikawa Medical College (AMC) succeeded in purifying the GPs by preparative isoelectric focusing; these higher quality GPs were suitable for ELISA. Based on the results of both IB and ELISA testing, developed at AMC for a field survey in Irian Jaya, it became evident that that area had pandemic NCC. We found many NCC patients, pigs full of cysts, and one dog infected with two cysts: these findings were based on serology. Recently, we conducted another survey to detect of the worm carriers of T. solium. Three of the 38 local people were positive by copro-antigen specific to Taenia species; these three patients expelled segments of Taenia spp and these were confirmed as those of T. solium by mitochondrial DNA analysis. When viable eggs of any taeniid species could be obtained, they can be developed into metacestodes in NOD-scid mice; it then becomes possible to analyze morphological dynamics, metacestode antigenicity, the efficacy of new metacestocidal drugs, and mitochondrial DNA. Mitochondrial DNA analysis of the specimens obtained in Irian Jaya was compared with that of other isolates worldwide. T. solium is now divided into two genotypes: the Asian type, and the Africa-American type. Some aspects of the pathological differences between the Asian and Africa-American types and the antigenic components of these two types are discussed.

Differential serodiagnosis of cystic and alveolar echinococcosis using native and recombinant antigens in Japan.

Our group at Asahikawa Medical College has established differential serodiagnosis for zoonotic larval cestodiases such as alveolar echinococcosis (AE), cystic echinococcosis (CE) and neurocysticercosis (NCC) using purified specific antigens. In this brief review, we introduce (a) four imported CE cases in Japan, easily identified serologically, (b) most recent advances in serology for differentiation of AE and monitoring of prognosis of AE in Japan. It includes application of affinity purified Em18 and prototype of a recombinant Em18 antigen. Serology using affinity purified Em18 antigens is showing much higher sensitivity for detection of AE cases which are usually undetectable by the ongoing serology for AE authorized in Hokkaido, Japan. As serology for AE, CE or NCC is still not popular in the majority of Asian countries, we expect that this review paper stimulates researchers who are interested in serology or serodiagnosis for these larval cestodiases including AE, CE and NCC.