DNA vaccination using schistosoma mansoni fimbrin gene on naive and infected praziquantel-treated mice

DNA immunization represents a promising vaccine strategy that has been reasonably successful, and will likely play a greater role in vaccine research development against Schistosoma mansoni [S. mansoni]. S. mansoni fimbrin [Smfim] gene which encodes a putative actin bundling tegumental and immunogenic protein has been cloned into the eukaiyotic expression vector pcDNAI/Amp and used for intra-muscular DNA vaccination of Swiss albino mice. Two experimental models were used to study its role on protection against S. mansoni infection in naive mice [model 1] and to explore its effect on infected praziquantel [PZQ]-treated mice [model 2] using different immunological, parasitological and histopathological parameters. In the first model, Smfim-vaccinated mice showed high anti-Smfim IgG titer and acquired a significant protection [43.2%; p< 0.01] with reduction of ova count in both hepatic and intestinal tissues [59.2% and 5 1.1% respectively, p< 0.01], significant reduction of granuloma count [24.1%; p< 0.01] and granuloma diameter [18.3%