title: Engineered Lactobacillus rhamnosus GG expressing IgG-binding domains of protein G: Capture of hyperimmune bovine colostrum antibodies and protection against diarrhea in a mouse pup rotavirus infection model.
abstract: Rotavirus-induced diarrhea causes more than 500,000 deaths annually in the world, and although vaccines are being made available, new effective treatment strategies should still be considered. Purified antibodies derived from hyperimmune bovine colostrum (HBC), from cows immunized with rotavirus, were previously used for treatment of rotavirus diarrhea in children. A combination of HBC antibodies and a probiotic strain of Lactobacillus (L. rhamnosus GG) was also found to be more effective than HBC alone in reducing diarrhea in a mouse model of rotavirus infection. In order to further improve this form of treatment, L. rhamnosus GG was engineered to display surface expressed IgG-binding domains of protein G (GB1, GB2, and GB3) which capture HBC-derived IgG antibodies (HBC-IgG) and thus target rotavirus. The expression of IgG-binding domains on the surface of the bacteria as well as their binding to HBC-IgG and to rotavirus (simian strain RRV) was demonstrated by Western blot, flow cytometry, and electron microscopy. The prophylactic effect of engineered L. rhamnosus GG and anti-rotaviral activity of HBC antibodies was evaluated in a mouse pup model of RRV infection. The combination therapy with engineered L. rhamnosus GG (PG3) and HBC was significantly more effective in reducing the prevalence, severity, and duration of diarrhea in comparison to HBC alone or a combination of wild-type L. rhamnosus GG and HBC. The new therapy reduces the effective dose of HBC between 10 to 100-fold and may thus decrease treatment costs. This antibody capturing platform, tested here for the first time in vivo, could potentially be used to target additional gastrointestinal pathogens.
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Immunology and Transfusion Medicine, Karolinska Institute at Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden.
authors.forename: Gökçe
authors.initials: G
authors.lastname: Günaydın
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Immunology and Transfusion Medicine, Karolinska Institute at Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden.
authors.forename: Ran
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Immunology and Transfusion Medicine, Karolinska Institute at Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden.
authors.forename: Lennart
authors.initials: L
authors.lastname: Hammarström
authors.affiliation: Department of Laboratory Medicine, Division of Clinical Immunology and Transfusion Medicine, Karolinska Institute at Karolinska University Hospital, Huddinge, SE-14186 Stockholm, Sweden. Electronic address: harold.marcotte@ki.se.
authors.forename: Harold
authors.initials: H
authors.lastname: Marcotte
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology; D002417:Cattle; D003126:Colostrum / Q000276:immunology*; D003967:Diarrhea / Q000628:therapy* / Q000821:virology; D004195:Disease Models, Animal; D005260:Female; D007074:Immunoglobulin G / Q000276:immunology; D052201:Lacticaseibacillus rhamnosus; D051379:Mice; D008807:Mice, Inbred BALB C; D012400:Rotavirus Infections / Q000276:immunology / Q000628:therapy*; D019562:Viral Load
chemical_list: D000914:Antibodies, Viral; D001426:Bacterial Proteins; D007074:Immunoglobulin G
keywords: GB1-3; HBC; HBC-IgG; Hyperimmune bovine colostrum; IgG; IgG-binding domains GB1, GB2, and GB3 of protein G; Lactobacillus rhamnosus GG; Neonatal mouse model; Probiotic; Protein G; RRV; Rotavirus; hyperimmune bovine colostrum; hyperimmune bovine colostrum derived-IgG antibodies; immunoglobulin G; rhesus rotavirus