Development of a Monoclonal Antibody to a Vibriophage as a Proxy for Vibrio cholerae Detection

• Authors: Md Abu Sayeed, University of Florida; Taylor Paisie, University of Florida; Meer Taifur Alam, University of Florida; Afsar Ali, University of Florida; Andrew Camilli, Tufts University; Jens Wrammert, Emory University; Ashraful Islam Khan, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b); Firdausi Qadri, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b); Marco Salemi, University of Florida; Gleen J Morris, University of Florida; Eric J Nelson, University of Florida
• Journal Title: INFECTION AND IMMUNITY
• Volume: Volume 90, Number 8
• Publisher: AMER SOC MICROBIOLOGY | 2022-07-18, Pages e0016122-e0016122
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1128/iai.00161-22
• Subjects: Health Sciences, Pathology; Health Sciences, Immunology; Biology, Microbiology
• Keywords: Science & Technology; Life Sciences & Biomedicine; Immunology; Infectious Diseases; bacteriophage; vibriophage; phage; ICP1; Vibrio cholerae; cholera; Bangladesh; rapid diagnostic tests (RDT); diarrhea; DENGUE VIRUS-INFECTION; PROTECTIVE ANTIGENS; RAPID DETECTION; DIAGNOSIS; STOOL; O139; SURVEILLANCE; EPIDEMICS; RESPONSES; DISEASES

Abstract

Cholera is an acute watery, diarrheal disease that causes high rates of morbidity and mortality without treatment. Early detection of the etiologic agent of toxigenic Vibrio cholerae is important to mobilize treatment and mitigate outbreaks. Monoclonal antibody (mAb) based rapid diagnostic tests (RDTs) enable early detection in settings without laboratory capacity. However, the odds of an RDT testing positive are reduced by nearly 90% when the common virulent bacteriophage ICP1 is present. We hypothesize that adding a mAb for the common, and specific, virulent bacteriophage ICP1 as a proxy for V. cholerae to an RDT will increase diagnostic sensitivity when virulent ICP1 phage is present. In this study, we used an in-silico approach to identify immunogenic ICP1 protein targets that were conserved across disparate time periods and locations. Specificity of targets to cholera patients with known ICP1 was determined, and specific targets were used to produce mAbs in a murine model. Candidate mAbs to the head protein demonstrated specificity to ICP1 by Enzyme linked immunosorbent assay (ELISA) and an ICP1 phage neutralization assay. The limit of detection of the final mAb candidate for ICP1 phage particles spiked into cholera stool matrix was 8 × 105 PFU by Western blotting analysis. This mAb will be incorporated into a RDT prototype for evaluation in a future diagnostic study to test the guiding hypothesis behind this study.