RESUMEN
Some biological and biochemical characteristics of metacercaria of Euparagonimus ce-nocopiosus obtained from crabs in the mountainous area of south Anhui, were compared with those of Paragonimus westermani from the same batch of crabs.The metacercariae of E. cenocopiosus prefer the location in heart rather than in the muscle of crabs. The average infection rate of crabs was 42.8% by E. cenocopiosus, while that by P. westermani was 100%. The infection rate of rats with E. cenocopiosus was 3/6 and 10/10 with P. westermani and the recovery rate of worm of these two species was 4.5-8.8% and 22-72.2% respectively. The number and pattern of protein bands of metacercaria of these two species by disc-PAGE and IEF technics were different.
RESUMEN
Objective To screen and identify the recombinants from the cDNA library of the adult Paragonimus west-ermani (PwA) for immunodiagnosis and immunoprophylaxis. Methods PwA cDNA library was screened with the PwA antigen immunized rabbit sera(IRS) pre-absorbed by the extract of E. coli XLl-Blue. The recombinants from positive clones were amplified by PCR, sequenced and cut off by KpnI/BarnHI and, then sub-cloned into pRESETB vector. The fusion protein was expressed,analysed by SDS-PAGE and identified by Western blotting with immune rabbit serum against worm antigen of Paragonimus westerrnani. Results The inserted cDNA fragment from the positive clone Pw-2 was about 800 bp, which contained an open reading frame(ORF) encoding Pw pre-procathepsin L belonging to cysteinase family. Expression product of Pw-2 was a fusion protein of 32 kDa, which can be recognized by immune rabbit serum against worm antigen of Paragonimus 晈esterrnani. Conclusion A recombinant plasmid Pw-2 encodes Pw pre-procathepsin L is constructed.
