Recognition of enteropathogenic Escherichia coli virulence determinants by human colostrum and serum antibodies

Area of Science:

• Immunology
• Microbiology
• Pediatrics

Background:

• Enteropathogenic Escherichia coli (EPEC) is a significant cause of diarrheal disease globally.
• Virulence factors like intimin and secreted proteins (EspA, EspB) are crucial for EPEC pathogenesis.
• The role of maternal antibodies transferred through breast milk in protecting neonates against EPEC is of public health importance, especially in endemic regions.

Purpose of the Study:

• To investigate the presence of antibodies against EPEC virulence factors in human colostrum and sera from Mexican mothers and their children.
• To analyze the infant antibody response to EPEC antigens from birth to 6 months of age.

Main Methods:

• Human colostrum and infant sera were collected at birth and 6 months.
• Antibodies against EPEC bundle-forming pilus (BfpA) and chromosomal virulence factors (intimin, EspA, EspB) were detected.
• Immunoglobulin A (IgA) in colostrum and Immunoglobulin G (IgG) in sera were analyzed.

Main Results:

• A high prevalence of IgA antibodies against EPEC virulence factors (EspA, intimin, EspB, BfpA) was found in colostrum samples.
• Infant IgG responses to EspA and intimin decreased from birth to 6 months.
• Infant IgG responses to BfpA significantly increased from 9% at birth to 71% at 6 months.
• Antibodies against EPEC intimin cross-reacted with intimin from enterohemorrhagic E. coli.

Conclusions:

• EPEC virulence factors, particularly BfpA and Esps, induce an antibody response in neonates.
• Breastfeeding plays a vital role in providing passive immunity against EPEC infections.
• These findings support the importance of breastfeeding in preventing diarrheal diseases in regions where EPEC is endemic.