Our new paper with Brian Geisbrecht lab is published this week in the Journal of Immunology. Congratulations Alec! In this project, we studied an immune evasion mechanism of the human bacterial pathogen Streptococcus agalactiae (also known as Group B Streptococcus or GBS). More specifically, we investigated the mechanism by which a surface protein called β protein recruits complement Factor H (FH) using biochemical and structural approaches and we studied the consequences of these interactions on immune evasion using functional studies.
We found
β binds to FH via a helical bundle motif located within its B75KN region.
β binds to FH in a manner that retains the complement regulatory activities of FH.
β enhances resistance to phagocytosis and killing, but not in an FH-dependent manner.
Group B Streptococcus Surface Protein β: Structural Characterization of a Complement Factor H–Binding Motif and Its Contribution to Immune Evasion
Xin Xu*, Alexander L. Lewis Marffy*, Andrew Keightley, Alex J. McCarthy and Brian V. Geisbrecht
*equal contribution
https://www.jimmunol.org/content/208/5/1232