Michael Affolter, Nestlé Research Centre, Switzerland
Michael Affolter1, Clara L. Garcia-Rodenas1, Gerard Vinyes-Pares2, Rosemarie Jenni1, Iris Roggero1, Ornella Avanti-Nigro1, Carlos Antonio De Castro1, Ai Zhao3, Yumei Zhang3, Peiyu Wang4, Sagar K. Thakkar1, and Laurent Favre1
1. Nestlé Research Center, Nestec Ltd., Switzerland;
2. Nestlé Research Center Beijing, Nestec Ltd., People’s Republic of China;
3. Department of Nutrition and Food Hygiene, Peking University, People’s Republic of China;
4. Department of Social Medicine and Health Education, Peking University, People’s Republic of China
Human breast milk protein composition may be impacted by lactation stage or factors related to geographical location. The present study aimed at 1) implementing a high-throughput protein quantification technique to 2) assessing the temporal changes of major breast milk proteins over lactation stages in a large cohort of urban mothers in China .
Various approaches have been exploited to identify and quantify milk proteins. Chromatographic or electrophoretic methods have been used to profile major milk proteins whereas immunobased techniques, i.e. ELISA or antibody arrays, were the method of choice for quantitative analysis of individual proteins. More recently, targeted LC-MS techniques have been developed to separate and quantify specific milk proteins. As the low throughput nature of these methodologies is often the limiting factor for application to larger numbers of samples, an innovative microfluidic chip-based method (LabChip) has been implemented and validated for the present analysis. 450 breast milk samples covering 8 months of lactation were analyzed for α-lactalbumin, lactoferrin, serum albumin, total caseins, immunoglobulins (IgA, IgM and IgG) and transforming growth factors (TGF) 1 and 2 content either by the microfluidic chip- or ELISA-based quantitative methods.
Results will be presented for all measured proteins and method performance criteria will be discussed for this novel approach. The combination of results from total protein measurements and total casein content determination allowed also an estimation of the whey to casein ratio present in the milk. Despite some limitations in the quantification of individual caseins with the microfluidic system, we believe that the minimal sample preparation and the 96-well sample format ideally combines speed and robustness of the analysis process and thus paves the way for a new technological standard for the measurement of proteins in future studies addressing breast milk protein composition.
 Michael Affolter, Clara L. Garcia-Rodenas, Gerard Vinyes-Pares, Rosemarie Jenni, Iris Roggero, Ornella Avanti-Nigro, Carlos Antonio De Castro, Ai Zhao, Yumei Zhang, Peiyu Wang, Sagar K.Thakkar and Laurent Favre, Temporal Changes of Protein Composition in Breast Milk of Chinese Urban Mothers and Impact of Caesarean Section Delivery, Nutrients 2016, 8, 504; doi:10.3390/nu8080504.Download PDF