Determinação do potencial do polissacarídeo O157 como antígeno vacinal contra a Escherichia coli produtora de toxina Shiga (STEC)

Abstract

Diarrheal diseases persist as a global concern due to their significant impact on health. Diarrhea, responsible for the death of 370,000 children worldwide in 2019, ranks as the second leading cause of mortality in children under five. Diverse factors, such as infections by parasitic, viral, or bacterial pathogens, trigger episodes of diarrhea, with Escherichia coli standing out, associated with hemolytic-uremic syndrome (HUS). The E. coli O157:H7 serotype, known for its Shiga toxin production, is linked to gastrointestinal infections and HUS, particularly in children. Treatment primarily involves supportive measures, as antibiotic exposure can exacerbate symptoms, increasing the risk of HUS and other complications. Due to this serotype's association with foodborne outbreaks, strict surveillance in food production, sanitation practices, and processes is essential to prevent infections caused by these pathogens. This study evaluates the potential of O157 polysaccharide as a vaccine candidate against Shiga toxin-producing E. coli (STEC). Results indicate that antibodies generated against O157 polysaccharide could recognize E. coli O157:H7 even in the presence of a capsule. They also assisted the complement system in lysing these bacteria and inhibited their adherence to human epithelial cells. In summary, the findings suggest that O157 polysaccharide could be considered a promising antigen in vaccine formulations against Shiga toxin-producing E. coli.