In JoVE (1)
Other Publications (9)
- BMJ (Clinical Research Ed.)
- QJM : Monthly Journal of the Association of Physicians
- PloS One
- Infectious Disease Clinics of North America
- Clinical and Vaccine Immunology : CVI
- Inflammatory Bowel Diseases
- The Journal of Antimicrobial Chemotherapy
- Nature Reviews. Gastroenterology & Hepatology
- Clinical and Experimental Gastroenterology
Articles by Tanya M. Monaghan in JoVE
A Protein Microarray Assay for Serological Determination of Antigen-specific Antibody Responses Following Clostridium difficile Infection Ola H. Negm1,2, Mohamed Hamed1,2, Tanya M. Monaghan3 1Breast Surgery Group, Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, Queen's Medical Centre, University of Nottingham, 2Medical Microbiology and Immunology Department, Faculty of Medicine, Mansoura University, 3Nottingham Digestive Diseases Centre and NIHR Nottingham Digestive Diseases Biomedical Research Centre, School of Medicine, Queen's Medical Centre, University of Nottingham This article describes a simple protein microarray method for profiling humoral immune responses to a 7-plex panel of highly purified Clostridium difficile antigens in human sera. The protocol can be extended for the determination of specific antibody responses in preparations of polyclonal intravenous immunoglobulin.
Other articles by Tanya M. Monaghan on PubMed
Circulating Antibody and Memory B-Cell Responses to C. Difficile Toxins A and B in Patients with C. Difficile-associated Diarrhoea, Inflammatory Bowel Disease and Cystic Fibrosis PloS One. | Pubmed ID: 24058568 C. difficile infection (CDI) is rarely reported in cystic fibrosis (CF) patients despite frequent hospitalisations and antibiotic usage. Conversely, the prevalence of CDI in inflammatory bowel disease (IBD) has received increased attention. We investigated components of the IgG-specific humoral immune response to C. difficile toxins A and B in patients with C. difficile-associated diarrhoea (CDAD), IBD patients with CDI, CF patients and healthy controls. Serum anti-toxin IgG was determined by ELISA. Circulating antigen-activated B-cells were investigated using Alexa Fluor 488-labelled toxin A and assessed by flow cytometry. Following induction of differentiation of memory B-cells, toxin A- and B-specific antibody secreting cells (ASCs) were quantified using ELISpot. We present the first data showing levels of serum anti-toxin A and B antibodies were significantly higher in patients with CF (without a history of CDI) than in CDAD patients and were stably maintained over time. Notably, the CDAD patients were significantly older than the CF patients. We also show that circulating toxin A-specific memory B-cells (IgD-negative) can be detected in CDAD patients [0.92 (0.09-1.78)%], and were prominent (5.64%, 1.14%) in two CF patients who were asymptomatic carriers of C. difficile. There was correlation between toxin A- and B-specific ASCs, with significantly higher proportions of the latter seen. In some with CDAD, high serum antibody levels were seen to only one of the two toxins. Mucosal secretion of toxin-specific IgG was detected in an additional group of IBD patients with no history of CDI. We conclude that enhanced and stable humoral immune responses to toxins A and B may protect CF and some IBD patients against CDI. The impaired ability to generate strong and/or sustained toxin-specific antibody and memory B-cell responses may increase susceptibility of older patients to CDI and highlight the need to investigate the role of immune senescence in future studies.
New Perspectives in Clostridium Difficile Disease Pathogenesis Infectious Disease Clinics of North America. | Pubmed ID: 25573674 Clostridium difficile is associated with a spectrum of clinical manifestations ranging from asymptomatic carriage to severe life-threatening pseudomembranous colitis. Current perspectives indicate that C difficile pathogenesis is a multifactorial disease process dictated by pathogenic toxin production, gut microbial dysbiosis, and altered host inflammatory responses. This article summarizes recent findings underpinning the cellular and molecular mechanisms regulating bacterial virulence and sheds new light on the critical roles of the host immune response, intestinal microbiota, and metabolome in mediating disease pathogenesis.
Profiling Humoral Immune Responses to Clostridium Difficile-Specific Antigens by Protein Microarray Analysis Clinical and Vaccine Immunology : CVI. | Pubmed ID: 26178385 Clostridium difficile is an anaerobic, Gram-positive, and spore-forming bacterium that is the leading worldwide infective cause of hospital-acquired and antibiotic-associated diarrhea. Several studies have reported associations between humoral immunity and the clinical course of C. difficile infection (CDI). Host humoral immune responses are determined using conventional enzyme-linked immunosorbent assay (ELISA) techniques. Herein, we report the first use of a novel protein microarray assay to determine systemic IgG antibody responses against a panel of highly purified C. difficile-specific antigens, including native toxins A and B (TcdA and TcdB, respectively), recombinant fragments of toxins A and B (TxA4 and TxB4, respectively), ribotype-specific surface layer proteins (SLPs; 001, 002, 027), and control proteins (tetanus toxoid and Candida albicans). Microarrays were probed with sera from a total of 327 individuals with CDI, cystic fibrosis without diarrhea, and healthy controls. For all antigens, precision profiles demonstrated
Pathogenesis of Clostridium Difficile Infection and Its Potential Role in Inflammatory Bowel Disease Inflammatory Bowel Diseases. | Pubmed ID: 26199993 Colonization with toxigenic Clostridium difficile may be associated with a wide spectrum of clinical presentation ranging from asymptomatic carriage to mild diarrhea to life-threatening colitis. Over the last 15 years, there has been a marked increase in the incidence of C. difficile infection, which predominantly affects elderly patients on antibiotics. More recently, there has been significant interest in the association between inflammatory bowel disease (IBD) and C. difficile infection. This review article discusses in some detail current knowledge of the mechanisms by which C. difficile toxins may mediate mucosal inflammation, together with the role of cell wall components of the microorganism in disease pathogenesis. Innate and adaptive host responses to C. difficile toxins and other components are described and include consideration of the potential role of known mucosal changes in IBD that may lead to an enhanced inflammatory response in the presence of C. difficile infection. Recent studies, which have characterized resident microbiota that may mediate protection against colonization by C. difficile, including their mechanisms of action, are also discussed. This includes the role of bile acids and 7α-dehydroxylase-expressing bacteria, such as Clostridium scindens. Recent studies suggest a higher carriage rate of C. difficile in patients with IBD. It is anticipated that future studies will determine the role of dysbiosis in IBD in predisposing to colonization with C. difficile.
Potential of Lactoferrin to Prevent Antibiotic-induced Clostridium Difficile Infection The Journal of Antimicrobial Chemotherapy. | Pubmed ID: 26759363 Clostridium difficile infection (CDI) is a global healthcare problem. Recent evidence suggests that the availability of iron may be important for C. difficile growth. This study evaluated the comparative effects of iron-depleted (1% Fe(3+) saturated) bovine apo-lactoferrin (apo-bLf) and iron-saturated (85% Fe(3+) saturated) bovine holo-lactoferrin (holo-bLf) in a human in vitro gut model that simulates CDI.
Clostridium Difficile Infection: Epidemiology, Diagnosis and Understanding Transmission Nature Reviews. Gastroenterology & Hepatology. | Pubmed ID: 26956066 Clostridium difficile infection (CDI) continues to affect patients in hospitals and communities worldwide. The spectrum of clinical disease ranges from mild diarrhoea to toxic megacolon, colonic perforation and death. However, this bacterium might also be carried asymptomatically in the gut, potentially leading to 'silent' onward transmission. Modern technologies, such as whole-genome sequencing and multi-locus variable-number tandem-repeat analysis, are helping to track C. difficile transmission across health-care facilities, countries and continents, offering the potential to illuminate previously under-recognized sources of infection. These typing strategies have also demonstrated heterogeneity in terms of CDI incidence and strain types reflecting different stages of epidemic spread. However, comparison of CDI epidemiology, particularly between countries, is challenging due to wide-ranging approaches to sampling and testing. Diagnostic strategies for C. difficile are complicated both by the wide range of bacterial targets and tests available and the need to differentiate between toxin-producing and non-toxigenic strains. Multistep diagnostic algorithms have been recommended to improve sensitivity and specificity. In this Review, we describe the latest advances in the understanding of C. difficile epidemiology, transmission and diagnosis, and discuss the effect of these developments on the clinical management of CDI.
High Prevalence of Subclass-specific Binding and Neutralizing Antibodies Against Toxins in Adult Cystic Fibrosis Sera: Possible Mode of Immunoprotection Against Symptomatic Infection Clinical and Experimental Gastroenterology. | Pubmed ID: 28765714 Despite multiple risk factors and a high rate of colonization for , the occurrence of infection in patients with cystic fibrosis is rare. The aim of this study was to compare the prevalence of binding toxin-specific immunoglobulin (Ig)A, IgG and anti-toxin neutralizing antibodies in the sera of adults with cystic fibrosis, symptomatic infection (without cystic fibrosis) and healthy controls.