title: A Tetraspecific VHH-Based Neutralizing Antibody Modifies Disease Outcome in Three Animal Models of Clostridium difficile Infection.
abstract: Clostridium difficile infection (CDI), a leading cause of nosocomial infection, is a serious disease in North America, Europe, and Asia. CDI varies greatly from asymptomatic carriage to life-threatening diarrhea, toxic megacolon, and toxemia. The incidence of community-acquired infection has increased due to the emergence of hypervirulent antibiotic-resistant strains. These new strains contribute to the frequent occurrence of disease relapse, complicating treatment, increasing hospital stays, and increasing morbidity and mortality among patients. Therefore, it is critical to develop new therapeutic approaches that bypass the development of antimicrobial resistance and avoid disruption of gut microflora. Here, we describe the construction of a single heteromultimeric VHH-based neutralizing agent (VNA) that targets the two primary virulence factors of Clostridium difficile, toxins A (TcdA) and B (TcdB). Designated VNA2-Tcd, this agent has subnanomolar toxin neutralization potencies for both C. difficile toxins in cell assays. When given systemically by parenteral administration, VNA2-Tcd protected against CDI in gnotobiotic piglets and mice and to a lesser extent in hamsters. Protection from CDI was also observed in gnotobiotic piglets treated by gene therapy with an adenovirus that promoted the expression of VNA2-Tcd.
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Diane J
authors.identifier: http://orcid.org/0000-0001-6606-4398
authors.initials: DJ
authors.lastname: Schmidt
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Gillian
authors.initials: G
authors.lastname: Beamer
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Tremblay
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Steele
authors.affiliation: Department of Animal Resources Science, Dankook University, Cheonan, Republic of Korea.
authors.forename: Hyeun Bum
authors.initials: HB
authors.lastname: Kim
authors.affiliation: School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Shanghai, People's Republic of China.
authors.forename: Yaunkai
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Michele
authors.initials: M
authors.lastname: Debatis
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Xingmin
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Radiation Oncology, Washington University, St. Louis, Missouri, USA.
authors.forename: Elena A
authors.initials: EA
authors.lastname: Kashentseva
authors.affiliation: Department of Radiation Oncology, Washington University, St. Louis, Missouri, USA.
authors.forename: Igor P
authors.initials: IP
authors.lastname: Dmitriev
authors.affiliation: Department of Radiation Oncology, Washington University, St. Louis, Missouri, USA.
authors.forename: David T
authors.initials: DT
authors.lastname: Curiel
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Shoemaker
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA saul.tzipori@tufts.edu.
authors.forename: Saul
authors.initials: S
authors.lastname: Tzipori
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000907:Antibodies, Bacterial / Q000627:therapeutic use*; D057134:Antibodies, Neutralizing / Q000627:therapeutic use*; D000992:Antitoxins / Q000627:therapeutic use*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors; D016360:Clostridioides difficile / Q000302:isolation & purification*; D003015:Clostridium Infections / Q000382:microbiology* / Q000628:therapy*; D004195:Disease Models, Animal; D004337:Drug Carriers; D004353:Drug Evaluation, Preclinical; D004768:Enterotoxins / Q000037:antagonists & inhibitors; D015316:Genetic Therapy / Q000379:methods; D008647:Mesocricetus; D008810:Mice, Inbred C57BL; D013552:Swine; D016896:Treatment Outcome
chemical_list: D000907:Antibodies, Bacterial; D057134:Antibodies, Neutralizing; D000992:Antitoxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004337:Drug Carriers; D004768:Enterotoxins; C041348:tcdA protein, Clostridium difficile; C031815:toxB protein, Clostridium difficile