"While we found that the microbiome of breast-fed infants is significantly enriched in genes associated with 'virulence,' including resistance to antibiotics and toxic compounds, we also found a correlation between bacterial pathogenicity and the expression of host genes associated with immune and defense mechanisms," said Robert Chapkin of Texas A&M University.
Iddo Friedberg of Miami University in Ohio said that the differences in virulence genes probably do not reflect an infection. "The breast-fed babies had a larger complement of gram-negative bacteria than the formula-fed babies. Gram-negative bacteria have genes that, although classified as 'virulent,' can activate the immune system but not cause an infection in the process. We are now studying this finding in greater depth," he said.
"The findings show that human milk feeding promotes the beneficial microbe population in the gut and crosstalk between these bacteria and the immune system of the infant and are helping us to define exactly why breast is best," said U of I scientist Sharon Donovan.
|Contact: Phyllis Picklesimer|
University of Illinois College of Agricultural, Consumer and Environmental Sciences