The value of bovine colostrums is documented in clinical observations and supported by large database. An antibacterial effect and modulation of the immune response are accepted. The wide spectrum of the activity of a lactoferrin or a proline-rich polipeptide complex was confirmed in experimental and clinical studies. Moreover, a high concentration of immunoglobulins in bovine colostrum gives exceptional opportunity for use as a support in immunodeficiency treatment.

Breast-feeding decreases the risk of breast cancer in mothers and infection, allergy, and autoimmunity in infants. The presence of mediators of the innate immune system in human milk, including soluble defensins, cathelicidins, and toll-like receptors (TLRs), has not been researched thoroughly. The whey fractions of colostrum and transitional and mature milk (n = 40) from normal mothers (n = 18) and from mothers with autoimmune or allergic diseases (n = 22) were analyzed for defensins by competitive enzyme-linked immunosorbent assay, and expression of messenger RNA (mRNA) for defensins, TLRs, and cathelicidin-derived antimicrobial peptide (LL-37) by cells in breast milk was determined by semiquantitative reverse-transcription-polymerase chain reaction. In whey, human neutrophil-derived a-defensin 1 (HNP-1) and human beta-defensin 2 (HBD-2) were present in the highest concentrations (median, 33.0 and 31.3 microg/mL, respectively), human alpha-defensin 6 (HD-6) was present in moderate amounts (3.1 microg/mL), and HD-5 and HBD-1 were present in the lowest concentrations (2.4 and 1.7 microg/mL, respectively). There was great variability of defensin levels between subjects, but there was no relation to autoimmune or allergic diagnosis. HNP-1, HD-5, and HD-6 were present in significantly higher levels in colostrum than in mature milk. Regarding defensin mRNA expression in the breast milk cells, 95% of the samples (n = 41) were positive for HBD-1, 68% were positive for HD-5, 22% were positive for HBD-3, 15% were positive for HBD-2, 5% were positive for HBD-4, and 2% were positive for HD-6; 88% (14/16) were positive for HNP-1. Breast milk cells also expressed mRNA for TLR1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR9, CD14, and LL-37. Human breast milk contains high concentrations of multiple defensin proteins and cells in breast milk express mRNA for these defensins, multiple TLRs, and LL-37. The innate immune system in breast milk is complex and likely provides protection for maternal breast tissue and the developing digestive tract of newborns.

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J Pept Sci. 2010 Jan;16(1):21-30.

Colostrum and bioactive, colostral peptides differentially modulate the innate immune response of intestinal epithelial cells.

J√∏rgensen AL, Juul-Madsen HR, Stagsted J.

Department of Food Science, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark.

Human milk contains biological factors that are involved in a newborn’s growth and immune system regulation. By integrating standard biochemical experimental protocols with computational methods, the present study investigates the presence of heme oxygenase-1 (HO-1), a cytoprotective enzyme, in human milk at different levels of maturation and in milk formulae. Furthermore, we evaluated cytokine and glutathione S-transferase (GSH) levels. Samples were collected from colostrum (on Day 1 after birth), from transition milk (on Postdelivery Days 7 and 14) and from mature milk (on Day 30 after delivery) in 14 healthy women. HO-1 protein, GSH and cytokines levels were measured using enzyme-linked immunosorbent assay and flow cytometry. HO-1 protein levels were significantly higher in colostrum (1.33 ng/ml; 5th centile 0.92; 95th centile 2.38) and in transition milk at 14 days (0.97 ng/ml; 5th centile 0.87; 95th centile 1.45) than in mature milk (0.9 ng/ml; 5th centile 0.8; 95th centile 1.38). Levels of HO-1 in milk formulae were similar to those in colostrum. No significant differences in GSH content were observed in mature milk, transition milk and colostrum, whereas significantly higher GSH levels were observed in milk formulae. No significant levels of cytokines, with the exception of interleukin-8, were found. Computational studies on the possible interactions between HO-1 and CD91 were carried out by a battery of softwares, namely, GRAMM (version 1.03), DALI, CLUSTALW (version 2.0), PatchDock and FireDock, mutually counterchecking and validating each other. The computational results, the strong convergence (to the same “solution”) of which finally leads to an “experimental-like” character, showed that HO-1 may bind to CD91, thus suggesting its major role as a new chaperokine in immune response regulation. These findings, which connect and integrate biochemical data and computational data interpretation, represent a synergistic and powerful means of conducting biological research.

Breast feeding improves the health of children. The greatest significance is to host defense, prevention of autoimmunity, and development of the digestive system; however, the underlying mechanisms for these effects are not well understood. Based on recent evidence that cytokines might be important in these processes, we have used ELISA to quantitate the cytokines in human colostrum, transitional, and mature milk from mothers delivering preterm or at term. We also used reverse transcription PCR to test breast milk cells for the production of cytokine mRNA. No significant (< 10 pg/ml) GM-CSF, SCF, LIF, MIP-1 alpha, IL-2, IL-4, IL-11, IL-12, IL-13, IL-15, sIL-2R, or IFN-gamma was detected. And, in contrast to earlier studies using bioassays or RIA, no significant IL-1 beta, TNF-alpha, or IL-6 was present; nor was IL-10, which had been tested using less specific antibodies. We did confirm the presence of high levels of M-CSF, which remained high throughout lactation. Human milk contained latent, but not free, TGF-beta 1, and especially TGF-beta 2, both of which may be activated by gastric acid pH. High levels of IL-1RA were detected, and like activated TGF-beta, may protect against autoimmunity. Chemokines, particularly GRO-alpha and MCP-1, but also RANTES and IL-8, were present and could protect against infection. Maternal cells in breast milk expressed mRNA for MCP-1 (20/20), IL-8 (14/20), TGF-beta 1 (14/16), TGF-beta 2 (4/6), M-CSF (9/12), IL-6 (6/12) and IL-1 beta (7/12), and may be a source of these cytokines. mRNA for IL-2, IL-10, IFN-gamma, TNF-alpha was not detected and only weak expression was found for RANTES (1/18). There was considerable variability between individual women, and women delivering preterm had lower levels of several cytokines in colostrum than women delivering at term. Yet, cytokine levels remained high months to years into lactation, providing immunological benefit to the breastfed infant/child.