N-Glycan Characterization of Cow Milk Immunoglobulins by CE-LIF

Alternative glycosylation of different glycoproteins and their role in various diseases attracts the attention of scientists and recent publications are reporting continuously about new findings in this area [1]. Bovine and human milk derived oral immunoglobulin preparations were used to treat gastrointestinal infections until the beginning of 2000s [2]. Furthermore, diet derived IgG could affect human innate immune system responses in a long term manner [3]. Albeit, N-glycan research in a well-studied field including immunoglobulins derived from cow milk and other animal sources, but still have some questions to be clarified [4]. In this study we have analyzed the IgG and IgA molecules captured from organic and non-organic cow milk colostrum (from local farms in Hungary) using protein G and IgA specific Z-domain variant Ni-IMAC columns. The glycan structures were released by PNGaseF digestion and labeled with a charged fluorophore aminopyrene trisulfonate (APTS), followed by purification with magnetic beads [5]. Analysis of the labeled glycans were carried out in an automated capillary electrophoresis system. Alterations in the N-glycan structures were found between organic and non-organic cow colostrum immunoglobulin samples, which could be the consequence of the different antibiotic or other treatments of the animals. Detailed structural characterization of the N-glycans found in both sample types will be given in a comprehensive comparable manner.