Human milk anti-inflammatory component contents during acute mastitis

Mastitis is a common complication of human lactation. We examined milk spec imens from eight women with clinical mastitis to determine their content of anti-inflammatory components. Antioxidant activity (spontaneous cytochrome c reducing activity), selected pro-inflammatory cytokines (IL-6, IL-1 beta ), selected endogenous cytokine control molecules (sIL-6R, sIL-1RII, and sT NFRI), lactoferrin, Na+:K+ ratios, and milk bioactivities that cause sheddi ng of sIL-1RII from human polymorphonuclear leukocytes (PMN), suppress PMN aggregation, and suppress PMN adherence responses were not increased compar ed to normal milks. Neither the bioactivities that deplete PAIN intracellul ar Ca2+ stores nor those that block Ca2+ influx into fMLP-stimulated PMN we re significantly increased in mastitis milks. In contrast, levels of TNF al pha, sTNFRII, and IL-1RA and bioactivities that cause shedding of sTNFRI fr om human PMN were significantly increased compared to normal milks. Mastiti s milk has the same anti-inflammatory components and characteristics of nor mal milk, with elevations in selected components/activities that may help p rotect the nursing infant from developing clinical illness due to feeding o n mastitis milk. (C) 2001 Academic Press.