AUTHOR=Nandakumar Kutty Selva , Collin Mattias , Happonen Kaisa E. , Lundström Susanna L. , Croxford Allyson M. , Xu Bingze , Zubarev Roman A. , Rowley Merrill J. , Blom Anna M. , Kjellman Christian , Holmdahl Rikard 

TITLE=Streptococcal Endo-β-N-Acetylglucosaminidase Suppresses Antibody-Mediated Inflammation In Vivo

JOURNAL=Frontiers in Immunology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2018.01623

DOI=10.3389/fimmu.2018.01623

ISSN=1664-3224

ABSTRACT=<p>Endo-β-<italic>N</italic>-acetylglucosaminidase (EndoS) is a family 18 glycosyl hydrolase secreted by <italic>Streptococcus pyogenes</italic>. Recombinant EndoS hydrolyzes the β-1,4-di-<italic>N</italic>-acetylchitobiose core of the N-linked complex type glycan on the asparagine 297 of the γ-chains of IgG. Here, we report that EndoS and IgG hydrolyzed by EndoS induced suppression of local immune complex (IC)-mediated arthritis. A small amount (1 µg given i.v. to a mouse) of EndoS was sufficient to inhibit IgG-mediated arthritis in mice. The presence of EndoS disturbed larger IC lattice formation both <italic>in vitro</italic> and <italic>in vivo</italic>, as visualized with anti-C3b staining. Neither complement binding <italic>in vitro</italic> nor antigen-antibody binding <italic>per se</italic> were affected. Thus, EndoS could potentially be used for treating patients with IC-mediated pathology.</p>