The Deleterious Effects of Shiga Toxin Type 2 Are Neutralized In Vitro by FabF8:Stx2 Recombinant Monoclonal Antibody

Author(s):Show less -

Luz, Daniela ^[1] ; Gomez, Fernando D. ^[2] ; Ferreira, Raissa L. ^[1] ; Melo, Bruna S. ^[1] ; Guth, Beatriz E. C. ^[3] ; Quintilio, Wagner ^[4] ; Moro, Ana Maria ^[4] ; Presta, Agostina ^[2] ; Sacerdoti, Flavia ^[2] ; Ibarra, Cristina ^[2] ; Chen, Gang ^[5] ; Sidhu, Sachdev S. ^[5] ; Amaral, Maria Marta ^[2] ; Piazza, Roxane M. F. ^[1]

Affiliation

^[1] Inst Butantan, Lab Bacteriol, BR-05503900 Sao Paulo - Brazil

^[2] Univ Buenos Aires, Fac Med, Dept Fisiol, Inst Fisiol Biofis Bernardo Houssay IFIBIO Ho, RA-1121 Buenos Aires, DF - Argentina

^[3] Univ Fed Sao Paulo, Dept Microbiol Imunol & Parasitol, BR-04023062 Sao Paulo - Brazil

^[4] Inst Butantan, Lab Biofarmacos, BR-05503900 Sao Paulo - Brazil

^[5] Univ Toronto, Terrence Donnelly Ctr Cellular & Biomol Res, Banting & Best Dept Med Res, Toronto, ON M5S 3E1 - Canada

• Document type: Journal article
• Source: TOXINS; v. 13, n. 11 NOV 2021.
• Web of Science Citations: 0

Abstract

Hemolytic Uremic Syndrome (HUS) associated with Shiga-toxigenic Escherichia coli (STEC) infections is the principal cause of acute renal injury in pediatric age groups. Shiga toxin type 2 (Stx2) has in vitro cytotoxic effects on kidney cells, including human glomerular endothelial (HGEC) and Vero cells. Neither a licensed vaccine nor effective therapy for HUS is available for humans. Recombinant antibodies against Stx2, produced in bacteria, appeared as the utmost tool to prevent HUS. Therefore, in this work, a recombinant FabF8:Stx2 was selected from a human Fab antibody library by phage display, characterized, and analyzed for its ability to neutralize the Stx activity from different STEC-Stx2 and Stx1/Stx2 producing strains in a gold standard Vero cell assay, and the Stx2 cytotoxic effects on primary cultures of HGEC. This recombinant Fab showed a dissociation constant of 13.8 nM and a half maximum effective concentration (EC50) of 160 ng/mL to Stx2. Additionally, FabF8:Stx2 neutralized, in different percentages, the cytotoxic effects of Stx2 and Stx1/2 from different STEC strains on Vero cells. Moreover, it significantly prevented the deleterious effects of Stx2 in a dose-dependent manner (up to 83%) in HGEC and protected this cell up to 90% from apoptosis and necrosis. Therefore, this novel and simple anti-Stx2 biomolecule will allow further investigation as a new therapeutic option that could improve STEC and HUS patient outcomes. (AU)

• FAPESP's process: 13/03160-9 - New strategies for recombinant antibodies generation against Stx1 and Stx2 toxins produced by Shiga toxin-producing E. coli
• Grantee: Daniela Luz Hessel da Cunha
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 19/24276-1 - Establishing efficient protocols and platforms for the obtainment of monoclonal biosimilar with a commercial interest: recombinant monoclonal antibodies anti-TNFa as a development model
• Grantee: Daniela Luz Hessel da Cunha
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/24659-5 - In vitro evaluation of the neutralizing capacity in human renal cell lines of recombinant Fab fragments against Shiga toxins
• Grantee: Raissa Lozzardo Ferreira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 18/13895-0 - Phage library for generation of recombinant antibodies: novel approaches for diagnosis and therapy of infections caused by different Escherichia coli pathotypes
• Grantee: Roxane Maria Fontes Piazza
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/17178-2 - OPTIMIZATION AND CHARACTERIZATION OF RECOMBINANT ANTIBODIES AND THEIR APPLICATION FOR DIAGNOSIS AND THERAPY OF SHIGA, HEAT-LABILE AND HEAT-STABLE ENTEROTOXINS
• Grantee: Roxane Maria Fontes Piazza
• Support Opportunities: Regular Research Grants