New vaccine platforms are crucial to address complex parasitic infections such as cutaneous leishmaniasis. Self-amplifying mRNA (SAM) based vaccines represent the next generation nucleic acid-based platform. In the present study, we compared the expression levels of PpSP15-LmSTI1 fusion gene in BHK-21 cells following transfection with Semliki Forest virus (SFV)-derived SAM, SFV-derived plasmid DNA (pSFV-PD) and conventional plasmid DNA (pcDNA3.
View Article and Find Full Text PDFA newly described coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative agent of coronavirus disease 2019 (COVID-19), has infected over 2.3 million people, led to the death of more than 160,000 individuals and caused worldwide social and economic disruption. There are no antiviral drugs with proven clinical efficacy for the treatment of COVID-19, nor are there any vaccines that prevent infection with SARS-CoV-2, and efforts to develop drugs and vaccines are hampered by the limited knowledge of the molecular details of how SARS-CoV-2 infects cells.
View Article and Find Full Text PDFLinear B-cell epitopes ((93)AKEFEAAAL(101) and (66)PQLTDVLN(73)) of CfaB were genetically fused to ltb-(gly)5-cfaB(1-25). Sera of rabbits immunized with fusion proteins reacted strongly with solid-phase bound ETEC bacteria bearing CFA/I fimbriae. Sera failed to agglutinate or inhibit hemagglutination promoted by CFA/I-positive strain which may be due to solvent inaccessibility of epitope residues on intact fimbriae.
View Article and Find Full Text PDFBackground: Toll-like receptor-5 (TLR-5) is a member of TLRs family and responsible for bacterial flagellin recognition. The activation of TLR-5 with flagellin leads to initiation of signaling cascades, which in turn results in transcription of pro-inflammatory cytokines. Regarding the critical role of TLR-5 agonists and antagonists in activation of innate immune responses, an increasing number of studies have focused on their therapeutic applications in drug and vaccine design.
View Article and Find Full Text PDFThe new generation of vaccines against infectious diseases is based on recombinant fusion proteins. Flagellin (FliC) of enteroaggregative Escherichia coli (EAEC) could be considered as a potent adjuvant in designing new vaccines. However, because of its large size, incorporation of this protein with a vaccine antigen might negatively influence recognition of the vaccine epitopes by the immune system.
View Article and Find Full Text PDFEnteroaggregative Escherichia coli (EAEC) is an important cause of acute and chronic diarrhea worldwide. It has been shown that flagellin (FliC), a major bacterial surface protein of EAEC, causes IL-8 release from certain epithelial cell lines via activation of TLR-5. Based on the ability of this protein to activate innate immunity, flagellin can be considered as a potent adjuvant in new vaccines and adjuvant effects of native or recombinant forms of flagellin have been demonstrated.
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