Nanoparticles-to-Antibodies in Novel in vitro Booster Vaccine Strategy
A new study stimulates human B cells with nanoparticles to result in proliferation, differentiation and antibody production
A group of researchers from the US. and U.K. have developed a novel, in vitro booster vaccine strategy that allows for antigen-specific human B cell activation and differentiation. Their approach stimulates human B cells in culture with streptavidin polystyrene nanoparticles coated with a mixture of antibodies and toll-like receptor (TLR) ligands.
After only a few days of culture, this stimulation results in antigen-specific B cell proliferation, differentiation of B cells into plasma cells and subsequent antibody production. The strategy could be used to produce therapeutic antibodies more quickly, as well as evaluate the immunogenicity of candidate antigens for new vaccines. The study was published July 24 in the Journal of Experimental Medicine.
B cells protect the body from infectious agents through surface B cell receptors (BCRs), which detect pathogen-derived antigens. TLR ligands like CpG can also cause B cell proliferation and differentiation, even without BCR signaling. But methods of expanding human B cell populations in vitro using CpG have been plagued by high cost and labor-intensive protocols. Also, they depend on donors who have been previously infected or vaccinated.
The authors created nanoparticles conjugated to both CpG and antigen to simulate human B cells. Using cells from healthy donors, the authors validated their nanoparticle approach with a wide range of infectious targets including tetanus toxoid, proteins from several subtypes of influenza A, and the HIV envelope protein gp120. B cells responded by producing monoclonal antibodies in vitro.