Title: Human Milk Retains Important Immunologic Properties After Defatting.
In: Journal of Parenteral and Enteral Nutrition 2020 Jul;44(5):904-911. doi: 10.1002/jpen.1722. Epub 2019 Oct 9.
Authors: Brittany Anne Jackson MD, Brigid Ellen Gregg MD, Sara Denise Tutor RDN, Jennifer Rachelle Bermick MD, Kate Peterson Stanley MD.
Abstract "Background: In neonatal chylothorax, thoracic lymphatic drainage is ineffective. The resultant effusions often require drainage, leading to a loss of immune components. Affected infants can be managed with formula or defatted human milk feedings low in long‐chain triglycerides to decrease lymph production. We hypothesized that there is no significant difference in the immunological profile or antibacterial effect of full‐fat and defatted human milk. Methods: Milk from lactating mothers was divided into 1 aliquot that was defatted via centrifugation with the full‐fat aliquot as control. Macronutrient content was analyzed with mid‐infrared spectroscopy. Flow cytometry was used to measure immune cell populations. Lactoferrin, lysozyme, immunoglobulin (Ig)A, and IgG values were determined using enzyme‐linked immunosorbent assay. The antibacterial properties were determined by inoculating paired full‐fat and defatted milk samples with Escherichia coli or Streptococcus pneumoniae bacteria and performing colony counts. Results: Compared with full‐fat milk, defatted milk demonstrated decreased total energy and fat and increased carbohydrate concentrations. Defatted milk demonstrated a significant decrease in all immune cell populations. There was no difference in IgA, IgG, lysozyme, or lactoferrin concentrations. Both aliquots demonstrated equivalent growth inhibition of E. coli and S. pneumoniae. Conclusions: Unexpectedly, defatted human milk contained significantly less leukocytes than full‐fat milk. IgA, IgG, lysozyme, and lactoferrin concentrations were preserved. The ability of defatted milk to inhibit bacterial growth was unaffected, suggesting that the antibacterial benefits of human milk remain after the defatting process. Further investigation regarding the clinical effect of leukocyte loss in defatted milk is warranted." Abstract only: https://onlinelibrary.wiley.com/doi/abs/10.1002/jpen.1722
Title: Origins of human milk microbiota: new evidence and arising questions.
In: Gut Microbes 2020 Nov 9;12(1):1667722. doi: 10.1080/19490976.2019.1667722. Published online: 04 Nov 2019.
Authors: Shirin Moossavi, Meghan B Azad.
Abstract: "Human milk contains a diverse community of bacteria. The growing appreciation of commensal microbes and increasing availability of high-throughput technology has set the stage for a theory-driven approach to the study of milk microbiota, and translation of this knowledge to improve maternal and child health. We recently profiled the milk microbiota of healthy Canadian mothers and applied theory-driven causal modeling, finding that mode of breast milk feeding (nursing directly at the breast vs. pumping and feeding breast milk from a bottle) was significantly associated with milk microbiota composition. This observation could reflect an increased exposure to pumps and/or a decreased exposure to the infant mouth. Either way, it provides evidence for the retrograde mechanism of milk inoculation. Here, we discuss the implications of this research and related controversies, and raise new questions about the origins and function of milk bacteria."
Open access: https://www.tandfonline.com/doi/full/10.1080/19490976.2019.1667722
Title: Early versus Delayed Fortification of Human Milk in Preterm Infants: A Systematic Review.
In: Neonatology 2020;117:24–32.
Authors: Alyahya W, Simpson J, Garcia AL, Mactier H, Edwards CA.
Abstract: "Expressed breast milk (EBM) is commonly supplemented with commercially prepared human milk fortifier to meet the additional nutritional needs of preterm infants. The optimal milk intake at which to introduce fortification is unknown. The objective of this systematic review was to compare the effect of early fortification (EF) versus that of delayed introduction of human milk fortifier (DF) on short-term outcomes including growth, feeding intolerance, length of hospital stay, and maturity at discharge in very-low-birth-weight infants. The search was carried out until March 2019 using 5 electronic databases (PubMed, Ovid Medline, Web of Science, Ovid Embase, and the Cochrane Library). The search was supplemented with a search of the clinical trial registry and reference lists. Eligible studies involved randomized controlled trials that had been designed to compare EF against DF using multi-nutrient fortifier for infants of a birth weight of <1,500 g who were fed exclusively or predominantly EBM. Four authors independently screened the studies for eligibility. A total of 1,972 articles were screened; 2 studies met the inclusion criteria and were included with a total number of participants of 171. The definition of EF and DF was not consistent between the 2 studies. There was no significant impact of EF versus DF on all outcomes. In conclusion, current data are limited and do not provide evidence on the optimal time to start fortification. The definition of EF and DF needs to be agreed upon and further larger randomized controlled trials are required."
Open access: https://www.karger.com/Article/FullText/501279