Development and Characterization of a Luminescence-Based High-Throughput Serum Bactericidal Assay (L-SBA) to Assess Bactericidal Activity of Human Sera against Nontyphoidal Salmonella

Aruta, Maria Grazia; Simone, Daniele De; Dale, Helen; Chirwa, Esmelda; Kadwala, Innocent; Mbewe, Maurice; Banda, Happy; Gordon, Melita A.; Pizza, Mariagrazia; Scorza, Francesco Berlanda; Nyirenda, Tonney S.; Canals, Rocı́o; Rossi, Omar; Collaborators, On Behalf Of The Vacc-iNTS Consortium

doi:10.3390/mps5060100

Cited by 2 publications

(2 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Enteritidis and S . Typhimurium in serum samples by using an iNTS standard sera [ 28 ]. Performing the correlation among the level of antibodies and antibody functionality from serum samples and clearance from the disease might allow us to define a protective threshold or correlate of protection, which could speed up vaccine development.…”

Section: Discussionmentioning

confidence: 99%

“…Unlike some other platforms, an ELISA format is easily transferred and accessible to resource-limiting settings, where the iNTS disease is endemic. We have also recently presented a high-throughput method to evaluate the ability to kill S. Enteritidis and S. Typhimurium in serum samples by using an iNTS standard sera [28]. Performing the correlation among the level of antibodies and antibody functionality from serum samples and clearance from the disease might allow us to define a protective threshold or correlate of protection, which could speed up vaccine development.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of Enzyme-Linked Immunosorbent Assay (ELISA) for Quantification of Antibodies against Salmonella Typhimurium and Salmonella Enteritidis O-Antigens in Human Sera

Aruta,

Lari,

De Simone

et al. 2023

BioTech

Self Cite

View full text Add to dashboard Cite

Nontyphoidal Salmonella (NTS) is a leading cause of morbidity and mortality caused by enteric pathogens worldwide in both children and adults, and vaccines are not yet available. The measurement of antigen-specific antibodies in the sera of vaccinated or convalescent individuals is crucial to understand the incidence of disease and the immunogenicity of vaccine candidates. A solid and standardized assay used to determine the level of specific anti-antigens IgG is therefore of paramount importance. In this work, we presented the characterization of a customized enzyme-linked immunosorbent assay (ELISA) with continuous readouts and a standardized definition of EU/mL. We assessed various performance parameters: standard curve accuracy, dilutional linearity, intermediate precision, specificity, limits of blanks, and quantification. The simplicity of the assay, its high sensitivity and specificity coupled with its low cost and the use of basic consumables and instruments without the need of high automation makes it suitable for transfer and application to different laboratories, including resource-limiting settings where the disease is endemic. This ELISA is, therefore, fit for purpose to be used for quantification of antibodies against Salmonella Typhimurium and Salmonella Enteritidis O-antigens in human samples, both for vaccine clinical trials and large sero-epidemiological studies.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Characterization of Enzyme-Linked Immunosorbent Assay (ELISA) for Quantification of Antibodies against Salmonella Typhimurium and Salmonella Enteritidis O-Antigens in Human Sera

Aruta,

Lari,

De Simone

et al. 2023

BioTech

Self Cite

View full text Add to dashboard Cite

show abstract

Serum susceptibility of Escherichia coli and its association with patient clinical outcomes

Poteete,

Cox,

Ruffin

et al. 2024

PLoS ONE

View full text Add to dashboard Cite

The innate immune system eliminates bloodstream pathogens such as Escherichia coli in part through complement protein deposition and subsequent bacterial death (i.e., “serum killing”). Some E. coli strains have developed mechanisms to resist serum killing, though the extent of variation in serum killing among bloodstream infection (BSI) isolates and the clinical impact of this variation is not well understood. To address this issue, we developed a novel assay that uses flow cytometry to perform high throughput serum bactericidal assays (SBAs) with E. coli BSI isolates (n = 183) to define the proportion of surviving bacteria after exposure to serum. We further determined whether E. coli resistance to serum killing is associated with clinical outcomes (e.g., in-hospital attributable mortality, in-hospital total mortality, septic shock) and bacterial genotype in the corresponding patients with E. coli BSI. Our novel flow cytometry-based SBA performed similarly to a traditional SBA, though with significantly decreased hands-on bench work. Among E. coli BSI isolates, the mean proportion that survived exposure to 25% serum was 0.68 (Standard deviation 0.02, range 0.57–0.93). We did not identify associations between E. coli resistance to serum killing and clinical outcomes in our adjusted models. Together, this study describes a novel flow cytometry-based approach to the bacterial SBA that allowed for high-throughput testing of E. coli BSI isolates and identified high variability in resistance to serum killing among a large set of BSI isolates.

show abstract

Development and Characterization of a Luminescence-Based High-Throughput Serum Bactericidal Assay (L-SBA) to Assess Bactericidal Activity of Human Sera against Nontyphoidal Salmonella

Cited by 2 publications

References 42 publications

Characterization of Enzyme-Linked Immunosorbent Assay (ELISA) for Quantification of Antibodies against Salmonella Typhimurium and Salmonella Enteritidis O-Antigens in Human Sera

Characterization of Enzyme-Linked Immunosorbent Assay (ELISA) for Quantification of Antibodies against Salmonella Typhimurium and Salmonella Enteritidis O-Antigens in Human Sera

Serum susceptibility of Escherichia coli and its association with patient clinical outcomes

Contact Info

Product

Resources

About