Diagnosis of early paragonimiasis is difficult because parasitological evidence is not easily obtained. Antibody tests have been proposed as a good substitute for classical diagnostic techniques. Using the crude extracts of Paragonimus westermani eggs, metacercariae, 4- and 7-week juveniles, and 16-week adults as antigens, we observed the early antibody responses. Sera were obtained from 4 experimental cats, fed 50 metacercariae each, at intervals until 13 weeks post-infection. Antibody (IgG) responses were identified by ELISA using extracts of 4-week juveniles, followed by those of 7- and 16-week worms. Antibody responses were minimal against the metacercarial extracts. Antibodies to P. westermani egg extracts were elevated after 10 weeks post-infection. In immunoblot analysis, more than nine protein bands in 4-week juveniles reacted with the early infection sera. Antigenic proteins in adult worms were different from those of juveniles. After four weeks of infection, 32 and 35 kDa bands in the adult extracts were increasingly reactive. Egg specific proteins at 28, 46 and 94 kDa were reactive only after 10 weeks. Antigenic components reacting to the early infection sera changed during the maturation stages of P. westermani; almost all juvenile antigens were replaced by adult antigen components.
Fig. 1 Antibody levels in the sera of early experimental cat paragonimiasis (mean-S.D., n=4) measured against five different antigenic preparations of P. westermani.
Fig. 2 Analysis of the crude extracts of different stages of P. westermani as seen by SDS-PAGE (Coomassie blue stained). Mr, molecular weight in kDa; MC*, metacercariae.
Fig. 3 Immunoblot analysis of the crude extracts of eggs (lanes Egg), 4-week old juveniles (lanes 4-wk) and 16-week old adults (lanes 16-wk) using the cat sera collected until 13-week of infection. Top indicates infection age of the examined sera. Mr, molecular weight in kDa. The experimental cat sera (n=4) were pooled, diluted at 1:400 in Tris-HCI containing 2% casein (w/v) and probed overnight. A 1:1,000 diluted peroxidase conjugated anti-cat IgG was used as a secondary antibody.
Cho SY, Kim SI, Kang SY, Kong Y, Han SK, Shim YS, Han YC. Antibody changes in paragonimiasis patients after praziquantel treatment as observed by ELISA and immunoblot. Korean J Parasitol 1989;27(1):15–21.
Chung YB, Kong Y, Yang HJ, Kang SY, Cho SY. Cysteine protease activities during maturation stages of Paragonimus westermani. J Parasitol 1997;83(5):902–907.
Huer B, Kim SI, Kang SY, Cho SY. Electrophoretic patterns of proteins from Paragonimus westermani in early developmental stages. Korean J Parasitol 1985;23(2):189–196.
Im JG, Kong Y, Shin YM, Yang SO, Song JG, Han MC, Kim CW, Cho SY, Ham EK. Pulmonary paragonimiasis: clinical and experimental studies. Radiographics 1993;13(3):575–586.
Indrawati I, Chaicumpa W, Setasuban P, Ruangkunaporn Y. Studies on immunodiagnosis of human paragonimiasis and specific antigen of Paragonimus heterotremus. Int J Parasitol 1991;21(4):395–401.
Itoh M, et al. Jpn J Parasitol 1988;37:575–586.
Joo KH, Hong SC, Chung MS, Rim HJ. [Analysis of antigenic specificities of Paragonimus westermani developmental stages using immunoblot technique]. Korean J Parasitol 1989;27(1):1–7.
Kang SY, Cho MS, Chung YB, Kong Y, Cho SY. A cysteine protease of Paragonimus westermani eggs. Korean J Parasitol 1995;33(4):323–330.
Kang SY, Kong Y, Cho SY. Component proteins in crude extract of adult Paragonimus westermani purified by immunoaffinity chromatography using monoclonal antibodies. Korean J Parasitol 1991;29(4):363–369.
Kim SH, Kong Y, Kim SI, Kang SY, Cho SY. Immunoblot observation of antigenic protein fractions in Paragonimus westermani reacting with human patients sera. Korean J Parasitol 1988;26(4):239–243.
Kong Y, Park CY, Kang SY, Cho SY. Tissue origin of soluble component proteins in saline extract of adult Paragonimus westermani. Korean J Parasitol 1992;30(2):91–100.
Maleewong W, Wongkham C, Intapan P, Pariyanonda S, Morakote N. Excretory-secretory antigenic components of Paragonimus heterotremus recognized by infected human sera. J Clin Microbiol 1992;30(8):2077–2079.
Slemenda SB, Maddison SE, Jong EC, Moore DD. Diagnosis of paragonimiasis by immunoblot. Am J Trop Med Hyg 1988;39(5):469–471.
Sugiyama H, Sugimoto M, Akasaka K, Horiuchi T, Tomimura T, Kozaki S. Characterization and localization of Paragonimus westermani antigen stimulating antibody formation in both the infected cat and rat. J Parasitol 1987;73(2):363–367.
Toscano C, et al. Trop Dis Bull 1995;92:R1–R26.
Yokogwa M, et al. Jpn J Parasitol 1962;11:117–122.
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