The Purification of 67kDa Antigen from AWA of Schistosoma japonicum and Its Application in Diagnosis and assessment of curative effect

Objective To evaluate the specificity and sensitivity of SjAWA67 in detecting specific antibodies in sera of patients with schistosomiasis japonica and in assessing therapeutic efficacy. Methods A major antigenic protein of 67kDa was purified from adult worm antigen of schistosoma japonicum (SjAWA) by SDS - PAGE and electric elution. SjAWA67 - ELISA was used to determine the specific IgG in sera of healthy individuals, patients with schistosomiasis japonica at different time after chemotherapy and patients with other parasitic diseases. Results SjAWA67 - ELISA was as sensitive and specific as SjSEA - ELISA. The negative conversion rate of IgG detected by SjAWA67 3 months after treatment was 45.5% , being significantly higher than 31.8% by AWA - ELISA and 11 .4% by SjSEA - ELISA respectively,and in addition,the parameter detected by SjAWA67 12 months after treatment was 90.9% , being significantly higher than 72.7% by AWA - ELISA and 52. 3% by SjSEA - ELISA respectively. Conclusion SjAWA67 is useful antigen for immunodiagnosis of schistosomiasis japonica.