Exposure to environmental bacteria may have differing effects on tumour necrosis factor‐α and interleukin‐6‐producing capacity in infancy

Abstract

Exposure to Gram-negative bacteria and their components may be associated with down-regulated immune responses in early infancy, indicated as an impaired production of pro-inflammatory cytokines following mitogen stimulation. Gram-positive bacteria and their constituents seem to have opposite effects. Of the measured markers, exposure to bioactive endotoxin appears to have the strongest impact on T-helper type 1 responses.