ABSTRACT
OBJECTIVE: To explore the relationship between the hemolymph phenol oxidase and melanization of oocysts. METHODS: Anopheles stephensi-Plasmodium yoelii system was used to determine the activity of monophenol oxidase (MPO) and o-diphenol oxidase (o-DPO) in the hemolymph collected from 4 groups of mosquitoes by polyacrylamide gel electrophoresis (PAGE) followed by density scanning. The 4 groups of mosquitoes were: non-blood-fed (N), normal-blood-fed (B), infected-blood-fed (I) and nitroquine-administrated (D), respectively. RESULTS: No significant difference was found in the activities of MPO and o-DPO between groups N and B. The activities of MPO and o-DPO were not obviously modified in group I, but were significantly increased on day 10 and decreased on day 15 after blood feeding in the group D as compared with those in the groups N and B. CONCLUSION: The alteration in the mosquito hemolymph PO activity coincided at each time point with the melanization of Plasmodium yoelii oocysts.
Subject(s)
Anopheles/enzymology , Hemolymph/enzymology , Insect Vectors/enzymology , Monophenol Monooxygenase/metabolism , Plasmodium yoelii/physiology , Animals , Anopheles/parasitology , Electrophoresis, Polyacrylamide Gel , Insect Vectors/parasitology , Oocysts/physiologyABSTRACT
OBJECTIVE: To analyse the soluble antigens of different developmental stages of Pagumogonimus skrjabini and develop a specific and sensitive serodiagnostic method for pagumogonimiasis. METHODS: The soluble antigens of P. skrjabini of various stages were separated by SDS-PAGE. The specific antigen of the adult fluke was recognized immunologically by immunoblot assay. The protein bands between 10-30 kDa purified by SDS-PAGE and electrophoretic elution were used in dot-ELISA. RESULTS: Using dot-ELISA, the soluble antigens of adult were recognized by sera infected with P. skrjabini. More reactive bands appeared at 10-30 kDa, but major protein bands were at 22, 24 and 26 kDa. However, using sera from patients infected with other trematodes including schistosome and Clonorchis, cross-reaction bands appeared within 60 to 90 kDa. When compared with ELISA of crude adult antigens for detecting 28 suspected patients, there was no significant difference between the two methods. The sera of 38 patients with other diseases were also detected by the two tests. No cross-reaction occurred with the purified adult antigen dot-ELISA while 13.2% (5/38) of the sera cross-reacted in ELISA of crude adult antigens. CONCLUSION: Dot-ELISA using 10-30 kDa antigen might be a specific and sensitive serodiagnostic method for diagnoing pagumogonimiasis.
