Interleukin-8 and Its Receptors in Human Milk from Mothers of Full-Term and Premature Infants

Abstract

In addition to its nutritional benefits, human milk also has bioactive elements. Limited immunological functions of newborns are supported and altered by the immunological elements of mother milk. Chemokines are of importance among these immune factors. Interleukin-8 (IL-8) has been demonstrated in mother's milk, and its receptors, CXC chemokine receptors (CXCR)-1 and CXCR-2, were detected on cells, responsible for immunological reactions and mammary glandular cells. The soluble forms of these receptors are yet to be described in human milk. In this study, it was aimed to assess the IL-8 levels and the concentrations of its receptors in colostrum and mature mother's milk in regard to preterm and term delivery. The results of this study indicated a decline in IL-8 levels with the lactation stage, but no difference was observed between term and preterm mother's milk. Regarding the CXCR-1 and CXCR-2, the concentrations of these receptors were similar in both colostrum and mature milk. Furthermore, there was not any significant difference between term and preterm mother's milk. In conclusion, this is the first study to investigate the concentrations of CXCR-1 and CXCR-2 with the levels of IL-8 in colostrum and mature human milk of term and preterm newborns. The alterations in IL-8 levels were similar in some of the studies reported. CXCR-1 and CXCR-2 levels did not demonstrate any significant difference. Further studies are required to investigate the soluble forms of these receptors and their relation to IL-8 with larger cohort.

Profile of pro-inflammatory cytokines in colostrum of nursing mothers at the extremes of reproductive age

“…age, we observed that there were no significant differences between the nursing mothers. Similarly, previous data showed no differences regarding IL-8 levels between term and preterm mother's milk [27]. Additionally, our results may reflect those from Munblit et al [13], who reported that cytokines are present at much lower levels than growth factors in breast milk, and that the cytokine decline over time was less consistent, suggesting that the role of IL-8 is constant during breastfeeding.…”

“…Breast milk has a protective role against neonatal sepsis, probably mediated by antimicrobial components and modulation of the neonatal immune system. Chemokines in human milk, such as IL-8, and their receptors CXC chemokine receptors (CXCR)-1 and CXCR-2, can activate the immune system of the neonate against invading pathogens [18,26,27]. In our study, when comparing the concentration of IL-8 in colostrum at the extremes of maternal…”

What’s Normal? Immune Profiling of Human Milk from Healthy Women Living in Different Geographical and Socioeconomic Settings

“…The production of IL8 by neonatal cells is reduced compared with adult cells (64) but, as with other immune factors, this developmental delay may be compensated for by ingesting human milk. A recent study reported that IL8 levels decline with stage of lactation (65). This is in contrast with our data since the mean concentration of this chemokine in KE samples (median: 74-day postpartum) was greater than in SW samples (median: 42-day postpartum).…”

A Review of the Immunomodulating Components of Maternal Breast Milk and Protection Against Necrotizing Enterocolitis

“…IL-8 expression by macrophages, endothelial cells, and epithelial cells provides chemotactic activity for a neutrophil-dependent response to acute inflammation, such as in sepsis and NEC. A decline in IL-8 levels in breast milk occurs with the advancement in lactational stage [69,70]. Although one study found no difference in breast milk IL-8 expression in mothers of infants of different gestational ages [63], others have identified higher IL-8 levels in the breast milk of mothers of preterm infants [69].…”