Immunoabsorbent nanoparticles based on a tobamovirus displaying protein A.
Earlier attempts to express peptides longer than 20 aa on the surface of tobamoviruses such as tobacco mosaic virus have failed. Surprisingly, we found that a functional fragment of protein A (133 aa) can be displayed on the surface of a tobamovirus as a C-terminal fusion to the coat protein via a 15-aa linker. The macromolecular nature of these nanoparticles allowed the design of a simple protocol for purification of mAbs with a recovery yield of 50% and > 90% product purity. The extremely dense packing of protein A on the nanoparticles (> 2,100 copies per viral particle) results in an immunoadsorbent with a binding capacity of 2 g mAb per g. This characteristic, combined with the high level of expression of the nanoparticles (> 3 g adsorbent per kg of leaf biomass), provides a very inexpensive self-assembling matrix that could meet the criteria for a single-use industrial immunoadsorbent for antibody purification.
Werner
Stefan
S
Icon Genetics and University of Halle, Biocenter, Weinbergweg 22, D-06120 Halle (Saale), Germany.
Marillonnet
Sylvestre
S
Hause
Gerd
G
Klimyuk
Victor
V
Gleba
Yuri
Y
D000911:Antibodies, Monoclonal / Q000302:isolation & purification / Q000378:metabolism; D036022:Capsid Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000648:ultrastructure; D049329:Nanostructures / Q000648:ultrastructure; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000648:ultrastructure; D013205:Staphylococcal Protein A / Q000235:genetics / Q000378:metabolism*; D017898:Tobamovirus / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D014771:Virion / Q000302:isolation & purification / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D036022:Capsid Proteins; D011993:Recombinant Fusion Proteins; D013205:Staphylococcal Protein A