TY - JOUR
T1 - IgG Binds Escherichia coli Serine Protease EspP and Protects Mice From E. coli O157:H7 Infection
AU - Tontanahal, Ashmita
AU - Sperandio, Vanessa
AU - Kovbasnjuk, Olga
AU - Loos, Sebastian
AU - Kristoffersson, Ann Charlotte
AU - Karpman, Diana
AU - Arvidsson, Ida
N1 - Funding Information:
The Swedish Research Council (2021-02200, 2017-01920 and K2015-99X-22877-01-6), The Knut and Alice Wallenberg Foundation (Wallenberg Clinical Scholar 2015.0320), Skåne Centre of Excellence in Health, The IngaBritt and Arne Lundberg’s Research Foundation, Olle Engkvist Byggmästare Foundation (all to DK). VS was supported by NIH grants: AI053067, AI154597, and AI155398. OK was supported by NIH grant P01 AI125181. SL was supported by a research fellowship from the Deutsche Forschungsgemeinschaft (LO 2021/2–1). The funding sources had no involvement in planning and carrying out any aspect of the project.
Funding Information:
The authors thank Charlotte Welinder at the Center for Translational Proteomics at the Medical Faculty, Lund University for assistance in sample preparation and mass spectrometry analysis. Lund University?s Bioimaging Centre (LBIC) is acknowledged for providing experimental resources. Dr. Harris Bernstein, NIDDK, NIH Bethesda MD is gratefully acknowledged for providing the EspP plasmid. Dr. Erik Johansson Khalessi carried out preliminary experiments (not included herein) as part of his master?s thesis. The authors thank Professor James Nataro, University of Maryland, for helpful advice.
Publisher Copyright:
Copyright © 2022 Tontanahal, Sperandio, Kovbasnjuk, Loos, Kristoffersson, Karpman and Arvidsson.
PY - 2022/2/18
Y1 - 2022/2/18
N2 - Shiga toxin-producing Escherichia coli O157:H7 is a virulent strain causing severe gastrointestinal infection, hemolytic uremic syndrome and death. To date there are no specific therapies to reduce progression of disease. Here we investigated the effect of pooled immunoglobulins (IgG) on the course of disease in a mouse model of intragastric E. coli O157:H7 inoculation. Intraperitoneal administration of murine IgG on day 3, or both on day 3 and 6, post-inoculation improved survival and decreased intestinal and renal pathology. When given on both day 3 and 6 post-inoculation IgG treatment also improved kidney function in infected mice. Murine and human commercially available IgG preparations bound to proteins in culture filtrates from E. coli O157:H7. Bound proteins were extracted from membranes and peptide sequences were identified by mass spectrometry. The findings showed that murine and human IgG bound to E. coli extracellular serine protease P (EspP) in the culture filtrate, via the IgG Fc domain. These results were confirmed using purified recombinant EspP and comparing culture filtrates from the wild-type E. coli O157:H7 strain to a deletion mutant lacking espP. Culture filtrates from wild-type E. coli O157:H7 exhibited enzymatic activity, specifically associated with the presence of EspP and demonstrated as pepsin cleavage, which was reduced in the presence of murine and human IgG. EspP is a virulence factor previously shown to promote colonic cell injury and the uptake of Shiga toxin by intestinal cells. The results presented here suggest that IgG binds to EspP, blocks its enzymatic activity, and protects the host from E. coli O157:H7 infection, even when given post-inoculation.
AB - Shiga toxin-producing Escherichia coli O157:H7 is a virulent strain causing severe gastrointestinal infection, hemolytic uremic syndrome and death. To date there are no specific therapies to reduce progression of disease. Here we investigated the effect of pooled immunoglobulins (IgG) on the course of disease in a mouse model of intragastric E. coli O157:H7 inoculation. Intraperitoneal administration of murine IgG on day 3, or both on day 3 and 6, post-inoculation improved survival and decreased intestinal and renal pathology. When given on both day 3 and 6 post-inoculation IgG treatment also improved kidney function in infected mice. Murine and human commercially available IgG preparations bound to proteins in culture filtrates from E. coli O157:H7. Bound proteins were extracted from membranes and peptide sequences were identified by mass spectrometry. The findings showed that murine and human IgG bound to E. coli extracellular serine protease P (EspP) in the culture filtrate, via the IgG Fc domain. These results were confirmed using purified recombinant EspP and comparing culture filtrates from the wild-type E. coli O157:H7 strain to a deletion mutant lacking espP. Culture filtrates from wild-type E. coli O157:H7 exhibited enzymatic activity, specifically associated with the presence of EspP and demonstrated as pepsin cleavage, which was reduced in the presence of murine and human IgG. EspP is a virulence factor previously shown to promote colonic cell injury and the uptake of Shiga toxin by intestinal cells. The results presented here suggest that IgG binds to EspP, blocks its enzymatic activity, and protects the host from E. coli O157:H7 infection, even when given post-inoculation.
KW - Escherichia coli O157:H7
KW - EspP
KW - Shiga toxin
KW - hemolytic uremic syndrome
KW - immunoglobulin G
KW - mouse
UR - http://www.scopus.com/inward/record.url?scp=85125838014&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85125838014&partnerID=8YFLogxK
U2 - 10.3389/fimmu.2022.807959
DO - 10.3389/fimmu.2022.807959
M3 - Article
C2 - 35250980
AN - SCOPUS:85125838014
VL - 13
JO - Frontiers in Immunology
JF - Frontiers in Immunology
SN - 1664-3224
M1 - 807959
ER -