Product safety in human milk banking: Development of a cell-based biosensor for screening pathogens and toxins in donated human milk
Human milk (HM) provides a unique blend of nutrition, immune stimulating and protective components to the newborn baby. It is particularly important for babies born preterm to be fed with HM where possible as it protects from devastating conditions such as necrotizing enterocolitis (Lucas et al. 1994). It is often difficult for new mothers of preterm infants to establish a good HM supply due to the stress and medical conditions associated with the early delivery and ongoing stress related to having a baby resident in a neonatal intensive care unit, as well as the requirement to mechanically pump breast milk.
HM banking is an initiative that seeks to support breastfeeding by providing pasteurized donated HM to the mothers of premature babies. This allows maternal supplies to be supplemented where required and replaces the use of cows’ milk based formula. The provision of HM to premature babies has been associated with improved infant outcomes. Currently in Perth, as a part of the quality control process for donor milk, all donated milk is screened by assessing representative pre- and post-pasteurization samples using culture based techniques. Whilst this is an effective method for eliminating samples contaminated with known pathogens or with an unacceptably high bacterial load, the efficacy of pasteurization in the removal of bacterial products such as heat-stable toxins is unknown.
In this study, cell culture based methods will be used to evaluate the effect of pasteurized milk on cell health and metabolism to simulate the effect of ingestion by premature babies. These “biosensor” cell-based assays will be optimized to rapidly assess HM samples and importantly will assess the efficacy and safety of alternative non-heat based treatment options such as ultra-violet light. It is anticipated that the use of biosensor assessment methodologies will provide a more quantitative measure of product safety and will lead to a better understanding of HM safety, possibly increase the efficiency of HM Banking (making more cost effective) and potentially improve the outcomes for very vulnerable premature babies.
Why my research is important
Milk banks currently only use conventional culture to assess donations. This new whole cell approach aims to measure the effect of the sample on a biologically relevant cell type to assess the effect on the infant gut. This method will help to develop and optimise a cell based culture biosensor to reliably detect bacterial toxins in donor human milk (DHM) to establish an objective measure of safety.