Interferon(IFN)-based therapy for hepatitis C virus(HCV) infection has recently been replaced by IFNfree direct-acting antiviral(DAA)-based therapy, which has been established as a 1^(st) line therapy with high effica...Interferon(IFN)-based therapy for hepatitis C virus(HCV) infection has recently been replaced by IFNfree direct-acting antiviral(DAA)-based therapy, which has been established as a 1^(st) line therapy with high efficacy and tolerability due to its reasonable safety profile. Resistance-associated substitutions(RASs) have been a weakness of DAA-based therapy. For example, combination therapy with daclatasvir and asunaprevir(DCV/ASV) is less effective for HCV genotype 1-infected patients with Y93H as a nonstructural protein 5A RAS. However, the problem regarding RASs has been gradually overcome with the advent of recently developed DAAs, such as sofosbuvir-based regimens or combination therapy with glecaprevir and pibrentasvir. Despite the high efficiency of DAA-based therapy, some cases fail to achieve viral eradication. P32 deletion, an NS5A RAS, has been gradually noticed in patients with DCV/ASV failure. P32 deletion has been sporadically reported and the prevalence of this RAS has been considered to be low in patients with DCV/ASV failure. Thus, the picture of P32 deletion has not been fully evaluated. Importantly, currently-commercialized DAA-based combination therapy was not likely to be effective for patients with P32 deletion. Exploring and overcoming this RAS is essential for antiviral therapy for chronic hepatitis C.展开更多
Mycoplasma genitalium is the main causative agent for non-gonococcal and non-chlamydial urethritis. P32 is the putative surface-exposed membrane protein of M. genitalium and it has substaintial identity in amino acid ...Mycoplasma genitalium is the main causative agent for non-gonococcal and non-chlamydial urethritis. P32 is the putative surface-exposed membrane protein of M. genitalium and it has substaintial identity in amino acid sequence with adhesin protein P30 from M. pnewnoniae. Since M. pneumoniae mutants lacking P30 protein is defective in cytadherence, P32 protein has been proposed to be an essential adhesin implicated in the adherence of M. genitalium to host cells. The prokaryotic expression vector pET-30 ( + )/p32 was constructed in the present study, and the recombinant protein was expressed in E. coli and purified under denaturing condition. As demonstrated by the immunoblotting analysis, the recombinant protein could react with rabbit antisera against M. genitalium, and adherence inhibition assays were petformed with antisera against this recombinant protein. It was demonstrated that P32 protein apperared to be an adhesion protein of M. genitalium, thus providing the experimental basis for better understanding of the pathogenesis of M. genitalium infection and for the development of the related vaccines against the infection.展开更多
文摘Interferon(IFN)-based therapy for hepatitis C virus(HCV) infection has recently been replaced by IFNfree direct-acting antiviral(DAA)-based therapy, which has been established as a 1^(st) line therapy with high efficacy and tolerability due to its reasonable safety profile. Resistance-associated substitutions(RASs) have been a weakness of DAA-based therapy. For example, combination therapy with daclatasvir and asunaprevir(DCV/ASV) is less effective for HCV genotype 1-infected patients with Y93H as a nonstructural protein 5A RAS. However, the problem regarding RASs has been gradually overcome with the advent of recently developed DAAs, such as sofosbuvir-based regimens or combination therapy with glecaprevir and pibrentasvir. Despite the high efficiency of DAA-based therapy, some cases fail to achieve viral eradication. P32 deletion, an NS5A RAS, has been gradually noticed in patients with DCV/ASV failure. P32 deletion has been sporadically reported and the prevalence of this RAS has been considered to be low in patients with DCV/ASV failure. Thus, the picture of P32 deletion has not been fully evaluated. Importantly, currently-commercialized DAA-based combination therapy was not likely to be effective for patients with P32 deletion. Exploring and overcoming this RAS is essential for antiviral therapy for chronic hepatitis C.
基金National Natural Science Foundation of China(No.30570093).
文摘Mycoplasma genitalium is the main causative agent for non-gonococcal and non-chlamydial urethritis. P32 is the putative surface-exposed membrane protein of M. genitalium and it has substaintial identity in amino acid sequence with adhesin protein P30 from M. pnewnoniae. Since M. pneumoniae mutants lacking P30 protein is defective in cytadherence, P32 protein has been proposed to be an essential adhesin implicated in the adherence of M. genitalium to host cells. The prokaryotic expression vector pET-30 ( + )/p32 was constructed in the present study, and the recombinant protein was expressed in E. coli and purified under denaturing condition. As demonstrated by the immunoblotting analysis, the recombinant protein could react with rabbit antisera against M. genitalium, and adherence inhibition assays were petformed with antisera against this recombinant protein. It was demonstrated that P32 protein apperared to be an adhesion protein of M. genitalium, thus providing the experimental basis for better understanding of the pathogenesis of M. genitalium infection and for the development of the related vaccines against the infection.
