Protein A Ligands


Most of the world's commercial monoclonal antibodies are purified using native and recombinant Protein A ligands manufactured by Repligen.

Protein A is a critical component of proprietary products that are used every day in biopharmaceutical purification processes supporting the safe and effective production of important breakthrough drugs for diseases such as rheumatoid arthritis, breast cancer and multiple sclerosis.

Since 1985, Repligen Protein A ligands have been used in small- to large-scale purification and immunoprecipitation, or by OEM partners who use them as critical raw materials in the manufacure of their own proprietary products.  

Recombinant Protein A is expressed in Escherichia coli (E. coli) as opposed to the native protein extracted from Staphylococcus aureus. Repligen leverages its expertise in the optimization of E. coli fermentation and purification processes to deliver Protein A ligands that enable very high expression levels and yield in downstream purification.

Repligen supplies Protein A ligands in milligram to multi-kilogram quantities.  

NGL-Impact® A Ligand

A next generation ligand co-developed by Repligen, NGL-Impact® A ligand is a paradigm-changing solution that can deliver higher performance, lower cost Protein A resin for capture chromatography.

rSPA Ligand

Native Recombinant Staphylococcal Protein A Ligand (rSPA) is the most advanced non-mutant Protein A ligand available from Repligen. 

Native Protein A Ligand

Native Protein A is a purification ligand used to isolate IgG from crude protein mixtures.  It binds with high affinity to the Fc region of IgG's. When immobilized on a matrix, e.g; Sepharose, Protein A (native) can be used to isolate IgG from crude protein mixtures.