Albumin and IgG Depletion From Serum/Plasma for Proteomics

• IgG removal >90% (70-80% of total Immunoglobulins removed)
• Albumin removal >95%
• Seamless and simple < 1 hour protocol
• Low abundance enrichment equivalent to immuno-affinity
• Disposable, cost-effective, no column regeneration or cross-contamination
• Works for most species tested including human, sheep, rat, mouse, bovine
• On-bead protocols improve workflow and efficiency, especially suited to targeted proteomics
• Suitable for LC-MS, 1 and 2D Gels, ELISAs, Enzyme and other Functional Assays.

The classical plasma proteins generally fall into functional categories, forming the vast majority of the mid-to-high abundance proteome. In serum, these sub-proteomes by mass content are: Albumin 50-60%; Immunoglobulins 10-20%; Transport Proteins (Transferrin, Apo) 5-10%; Complement related Proteins 3-5%; Protease Inhibitors 2-5%; and all others 2-5%. While these sub-proteomes are required for normal body homeostasis, they nevertheless can become dysfunctional during acute-phase and chronic stimuli.

So, depending on the needs of the investigation, it can be valuable to consider that one or more of these categorical sub-proteomes is simply background noise whereby depletion is beneficial. While in other cases, these same categorical sub-proteomes might provide new data and information and consequently, should not be depleted. Different AlbuVoid™, AlbuVoid™ PLUS and AlbuSorb™ PLUS workflows support different proteomic biases as outlined in the following Table.

Products and digest conditions produce different sub-proteome windows of observation. So, depending on the needs of the investigation, it can be valuable to consider that one or more of these categorical sub-proteomes is simply background noise whereby depletion is beneficial. While in other cases, these same categorical sub-proteomes might provide new data and information and consequently, should not be depleted. Categorically the acute-phase sub-proteomes differentiated in disease may vary greatly from those associated with chronic sub-proteomes. So there is great benefit in having options to enrich or deplete one or more of these sub-proteomes.

BSG"s Albumin and IgG Removal Kits offer many such options:

• The "PLUS" products substantially deplete Immunoglobulins through separations at the protein level.
• The variable regions of Immunoglobulins are extremely heterogeneous, generating a background noise across the full LC gradient. On-bead digestion (BASP™) with AlbuVoid™ substantially reduces the influence of such Ig peptide features. So in addition to workflow simplicity, BASP™ can be advantageous utilized in targeted proteomic workflows whenever the target proteins do not require strong denaturing conditions.
• With the exception of Immunoglobulins whereby FASP generates many more spectral features, both strong denaturing conditions (FASP) and on-bead digest (BASP™) conditions produce similar protein profiles.
• Both Apolipoproteins and heavily glycosylated proteins (i.e., α1-Acid Glycoprotein) bind poorly to AlbuVoid™. For quantitative studies within these classes of proteins, AlbuSorb™ PLUS is recommended.
• The Complement sub-proteome is especially enriched by AlbuVoid™ PLUS. The digest conditions may bias towards one or more functional sub-populations, likely due to conformational transitions and protein-protein interactions (i.e., Factor Bb, Properdin) that occur upon activation. This needs further investigation.
• The low abundance sub-proteome is enriched 5+ fold with AlbuVoid™ and 4+ fold with AlbuSorb™ PLUS.