Characterisation of the protein matrix of quality control sera by a high resolution two-dimensional electrophoresis...

A high resolution two-dimensional electrophoresis technique (Iso-Dalt) has been employed to characterise the protein components of freshly drawn human serum and various human- and animal-based quality control sera. This technique allows a direct comparison to be made between the protein components of different materials. Similarities have been demonstrated between the protein components (protein matrix) of freshly drawn human serum and human-, equine- and bovine-based control sera, though some differences existed between sera from these three sources, mainly in the acidic high molecular weight quadrant and the lipoprotein and haptoglobin regions. The Iso-Dalt technique also revealed differences in the protein matrices of the various human-based quality control sera tested. Differences attributable to manufacturing technique were also discernible by inspection of the two-dimensional maps of the protein matrices. Although characterisation and comparison of protein components of the matrix of serum is difficult, the Iso-Dalt technique has proved a valuable tool in this characterisation and the subsequent assessment of the similarity of quality control sera to human serum. This type of information is valuable when considering the suitability of human- or animal-based sera for use in internal and external quality control procedures.