Escherichia coli (E. coli) is a Gram-negative bacterium that belongs to the family Enterobacteriaceae. While E. coli can stay as an innocuous resident in the digestive tract, it can cause a group of symptoms ranging from diarrhea to live threatening complications. Due to the increased rate of antibiotic resistance worldwide, the development of an effective vaccine against E. coli pathotypes is a major health priority. In this study, a reverse vaccinology approach along with immunoinformatics has been applied for the detection of potential antigens to develop an effective vaccine. Based on our screening of 5,155 proteins, we identified lipopolysaccharide assembly protein (LptD) and outer membrane protein assembly factor (BamA) as vaccine candidates for the current study. The conservancy of these proteins in the main E. coli pathotypes was assessed through BLASTp to make sure that the designed vaccine will be protective against major E. coli pathotypes. The multitope vaccine was constructed using cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and B cell lymphocyte (BCL) epitopes with suitable linkers and adjuvant. Following that, it was analyzed computationally where it was found to be antigenic, soluble, stable, and non-allergen. Additionally, the adopted docking study, as well as all-atom molecular dynamics simulation, illustrated the promising predicted affinity and free binding energy of this constructed vaccine against the human Toll-like receptor-4 (hTLR-4) dimeric state. In this regard, wet lab studies are required to prove the efficacy of the potential vaccine construct that demonstrated promising results through computational validation.

Helicobacter pylori, previously known as Campylobacter pylori, is the most famous causative agent of stomach ulcer, duodenal ulcer, gastritis, and gastric cancer and it has a direct relation with other gastric malignancies. It is a ubiquitous organism that is present in a percent of 30-100% of the global population. This percentage varies according to different geographical locations. Clinical manifestation, transmission, method of diagnosis, management of the infection, and even the treatment differs from region to region. In this review, we are concentrating on the above-mentioned factors that affect H. pylori infection epidemiology and we are directing the spotlight towards the epidemiology of this bacterium in Egypt. We have summarized different tools of diagnosis and the most famous modes of transmission of this infection in Egypt and mentioned our recommendations for future research investigation in these aspects. For example, using pulsedfield gel electrophoresis and next-generation sequencing for the full genomic characterization of H. pylori samples from this geographical area.