Characterization of IVIG Products by Mass Spectrometry
As the demand for IVIG grows and IVIG is used to treat more patients with both immune deficiencies and autoimmune disorders, there is an increased need to provide higher yield, higher purity, and better characterized products. Haemtech has been a leader in IVIG analysis by ELISA and functional assays, and now we have added the power of mass spectrometry to our services. We use LC-MS and LC-MS/MS methods to characterize IVIG products – both finished drug substance/product samples and process intermediates.
IVIG Impurity Analysis by LC-MS/MS
Many methods such as immunoassays and activity assays are used to assess IVIG purity with respect to specific contaminants (e.g., IgA, IgM, Factor XIa, plasmin). These assays are targeted. Mass spectrometry is untargeted. Another way to think of it - mass spectrometry is multiplexed without the need to generate the antibodies needed for immunoassays.
The question often asked is, “Polyclonal IVIG has thousands of different antibodies in it. How can the mass spectrometer find impurities in such a complex product?”
Our answer: Sure, IVIG is a complex product, but we have state-of-the-art instrumentation and have developed methods that cut through the complexity and enable us to detect contaminant proteins (CPs) in IVIG products that are in the 10 parts-per-million range (on a mole- or mass-basis).
We have shown our methods work with multiple commercial IVIG products sold in the United States.
We have also worked with groups that are developing new purification methods for IVIG, enabling them to gain a deeper understanding of the impurities at each step of the process. If someone knows exactly where important impurities are eluting off their column, and understands the fundamental properties of these impurities such as MW and pI, the purification process can be more rationally refined to eliminate those impurities – optimizing both yield and purity.
Contaminant proteins we typically identify and quantitate in a single injection of an IVIG sample include the following:
- IgA, IgM, IgD, IgE
- Complement proteins
- Coagulation-related proteins
- ApoH or Beta-2-Glycoprotein 1
- Many more, depending on the type of sample
Contact us if you would like to hear more about IVIG contaminant protein analysis by mass spectrometry.
IVIG Glycosylation Analysis
Several studies have been published demonstrating that the glycosylation of antibodies in IVIG preparations may play an important role in treatment of autoimmune disorders or infectious disease.
- Controlled tetra-Fc sialylation of IVIg results in a drug candidate with consistent enhanced anti-inflammatory activity
- Afucosylated IgG characterizes enveloped viral responses and correlates with COVID-19 severity
The methods we use for characterizing glycosylation of recombinant proteins can also be used for IVIG products. Contact us if you are interested in exploring this with your samples.
For more information, please contact us.