Designing and structure evaluation of multi-epitope vaccine against ETEC and EHEC, an in silico approach

Abstract

Diarrheal diseases represent a major health problem in developing countries. Several viruses and bacterial agents, such as Enterotoxigenic Escherichia coli (ETEC) and Enterohemorrhagic Escherichia coli (EHEC) are responsible for human enteric infections. In humans, EHEC infections result in bloody or non-bloody diarrhea, which may be complicated by haemorrhagic colitis and haemolytic uraemic syndrome (HUS). Infection by ETEC is accompanied by a non inflammatory watery diarrhea. E. coli follows a common strategy of infection: colonization on a mucosal site, evasion of host defenses, multiplication, and host damage. Intimin, Stx, Lt and Cfa proteins are the virulence factors expressed by these strains. Antibiotic treatment is generally not recommended for most cases of diarrhea, since antibiotic usage may lead to antibiotic resistance in ETEC and may also change the intestinal flora. We hypothesized that the chimeric forms of these effectors as vaccine candidates would reduce the colonization of bacteria. This study is based on an in silico analysis of chimeric protein structure and its stability and solubility. The secondary and tertiary structures of selected domains were also predicted. Moreover, T and B cell epitopes were mapped. Protein structure Prediction showed that each domain of antigen was separated completely also stable for recombinant expression. We believe that this chimeric vaccine candidate is effective for prevention of bacteria caused diarrheal diseases.

Towards the first multi-epitope recombinant vaccine against Crimean-Congo hemorrhagic fever virus: A computer-aided vaccine design approach

“…Although not much time has passed since the introduction of the first report about computational vaccine design, in the recent years, a lot of progress has been made in this regard. Subsequently, numerous vaccines were developed based on computational approaches that include efficient vaccine against Toxoplasma gondii [31], Rickettsia prowazekii [32], Streptococcus pneumoniae [33], Leishmania infantum [34], Chlamydia pneumoniae [35], Brucella abortus [36], Staphylococcus aureus [15], Escherichia coli [37], Vibrio cholera [38], Human immunodeficiency virus-1 [39], Hepatitis C virus [40] and many others. In many empirical studies, the efficacy of computationally designed vaccines is approved [34,39,41,42].…”

In silico Designing of an Epitope-Based Vaccine Against Common E. coli Pathotypes

“…We can divide these studies into two main categories, firstly, studies that just predicted single B and T cell epitopes of protein candidates of certain pathotypes of E. coli such as Khan and Kumar (77) and Mehla and Ramana (78). Secondly, more advanced studies that designed and validated a multitope vaccine through a computational approach such as (79), where the vaccine was designed based on Intimin, Stx, Lt, and Cfa proteins and directed against ETEC and EHEC, Another study (80), the vaccine was designed based on IutA and FimH proteins and directed against UPEC, a third study (81), the vaccine was designed based on the bacterial type-3 secretion system and directed against extraintestinal pathogenic E. coli. In the current study, we followed the approach of the second group of studies but at the same time, we introduced two unique points that greatly affect the design and the potential application.…”