Abstract
Background Colostrum is the first milk that supplies newborns with immune supporting peptides. Due to its heterogeneous and variable characteristic, standardized assays for assessment of its biological activities are a challenge. Current set of studies were aimed to investigate the immune activity of bovine colostrum blends and different fractions as well as validate a method to assess variability across different lots.
Methods Immune activity of a bovine colostrum blend and different fractions was evaluated by their ability to enhance PBMC-mediated killing of K562 cells. K562 cell killing was assessed by flow cytometry using DAPI. PBMCs derived from multiple healthy donors were initially investigated. Sample from the highest responder was used for subsequent studies. Different lots of product were assessed.
Results Bovine colostrum blend and different fractions similarly reduced K562 cells number and these effects were generally greater than IL-2 control. Despite consistently effective at enhancing PBMCs-mediated K562 killing, the degree of the effect was significantly variable across different lots. These biological effects were dependable on the solubility of the product.
Conclusion Assessment of PBMC-mediated killing of K562 cells by flow cytometry using DAPI is a reliable method for measuring immune activity of bovine colostrum and different fractions as long as product is well dissolved into solution and the same biological sample from a single donor is used for investigation of batch-to-batch variability.
- Copyright © 2019 by The American Association of Immunologists, Inc.