Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A

The first phase IIb safety and efficacy trial of a new tuberculosis vaccine since that for BCG was completed in October 2012. BCG-vaccinated South African infants were randomized to receive modified vaccinia virus Ankara, expressing the Mycobacterium tuberculosis antigen 85A (MVA85A), or placebo. MV...

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Main Authors:	Harris, Stephanie A., Satti, Iman, Matsumiya, Magali, Stockdale, Lisa, Chomka, Agnieszka, Tanner, Rachel, O'Shea, Matthew K., Manjaly Thomas, Zita-Rose, Tameris, Michele, Mahomed, Hassan, Scriba, Thomas J., Hanekom, Willem A., Fletcher, Helen A., McShane, Helen
Format:	Online
Language:	English
Published:	American Society for Microbiology 2014
Online Access:	https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4097435/

id	pubmed-4097435
recordtype	oai_dc
spelling	pubmed-40974352014-07-25 Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A Harris, Stephanie A. Satti, Iman Matsumiya, Magali Stockdale, Lisa Chomka, Agnieszka Tanner, Rachel O'Shea, Matthew K. Manjaly Thomas, Zita-Rose Tameris, Michele Mahomed, Hassan Scriba, Thomas J. Hanekom, Willem A. Fletcher, Helen A. McShane, Helen Vaccines The first phase IIb safety and efficacy trial of a new tuberculosis vaccine since that for BCG was completed in October 2012. BCG-vaccinated South African infants were randomized to receive modified vaccinia virus Ankara, expressing the Mycobacterium tuberculosis antigen 85A (MVA85A), or placebo. MVA85A did not significantly boost the protective effect of BCG. Cryopreserved samples provide a unique opportunity for investigating the correlates of the risk of tuberculosis disease in this population. Due to the limited amount of sample available from each infant, preliminary work was necessary to determine which assays and conditions give the most useful information. Peripheral blood mononuclear cells (PBMC) were stimulated with antigen 85A (Ag85A) and purified protein derivative from M. tuberculosis in an ex vivo gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISpot) and a Ki67 proliferation assay. The effects of a 2-h or overnight rest of thawed PBMC on ELISpot responses and cell populations were determined. Both the ELISpot and Ki67 assays detected differences between the MVA85A and placebo groups, and the results correlated well. The cell numbers and ELISpot responses decreased significantly after an overnight rest, and surface flow cytometry showed a significant loss of CD4+ and CD8+ T cells. Of the infants tested, 50% had a positive ELISpot response to a single pool of flu, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) (FEC) peptides. This pilot work has been essential in determining the assays and conditions to be used in the correlate study. Moving forward, PBMC will be rested for 2 h before assay setup. The ELISpot assay, performed in duplicate, will be selected over the Ki67 assay, and further work is needed to evaluate the effect of high FEC responses on vaccine-induced immunity and susceptibility to tuberculosis disease. American Society for Microbiology 2014-07 /pmc/articles/PMC4097435/ /pubmed/24828094 http://dx.doi.org/10.1128/CVI.00128-14 Text en Copyright © 2014 Harris et al. http://creativecommons.org/licenses/by/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution 3.0 Unported license (http://creativecommons.org/licenses/by/3.0/) .
repository_type	Open Access Journal
institution_category	Foreign Institution
institution	US National Center for Biotechnology Information
building	NCBI PubMed
collection	Online Access
language	English
format	Online
author	Harris, Stephanie A. Satti, Iman Matsumiya, Magali Stockdale, Lisa Chomka, Agnieszka Tanner, Rachel O'Shea, Matthew K. Manjaly Thomas, Zita-Rose Tameris, Michele Mahomed, Hassan Scriba, Thomas J. Hanekom, Willem A. Fletcher, Helen A. McShane, Helen
spellingShingle	Harris, Stephanie A. Satti, Iman Matsumiya, Magali Stockdale, Lisa Chomka, Agnieszka Tanner, Rachel O'Shea, Matthew K. Manjaly Thomas, Zita-Rose Tameris, Michele Mahomed, Hassan Scriba, Thomas J. Hanekom, Willem A. Fletcher, Helen A. McShane, Helen Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
author_facet	Harris, Stephanie A. Satti, Iman Matsumiya, Magali Stockdale, Lisa Chomka, Agnieszka Tanner, Rachel O'Shea, Matthew K. Manjaly Thomas, Zita-Rose Tameris, Michele Mahomed, Hassan Scriba, Thomas J. Hanekom, Willem A. Fletcher, Helen A. McShane, Helen
author_sort	Harris, Stephanie A.
title	Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
title_short	Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
title_full	Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
title_fullStr	Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
title_full_unstemmed	Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A
title_sort	process of assay selection and optimization for the study of case and control samples from a phase iib efficacy trial of a candidate tuberculosis vaccine, mva85a
description	The first phase IIb safety and efficacy trial of a new tuberculosis vaccine since that for BCG was completed in October 2012. BCG-vaccinated South African infants were randomized to receive modified vaccinia virus Ankara, expressing the Mycobacterium tuberculosis antigen 85A (MVA85A), or placebo. MVA85A did not significantly boost the protective effect of BCG. Cryopreserved samples provide a unique opportunity for investigating the correlates of the risk of tuberculosis disease in this population. Due to the limited amount of sample available from each infant, preliminary work was necessary to determine which assays and conditions give the most useful information. Peripheral blood mononuclear cells (PBMC) were stimulated with antigen 85A (Ag85A) and purified protein derivative from M. tuberculosis in an ex vivo gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISpot) and a Ki67 proliferation assay. The effects of a 2-h or overnight rest of thawed PBMC on ELISpot responses and cell populations were determined. Both the ELISpot and Ki67 assays detected differences between the MVA85A and placebo groups, and the results correlated well. The cell numbers and ELISpot responses decreased significantly after an overnight rest, and surface flow cytometry showed a significant loss of CD4+ and CD8+ T cells. Of the infants tested, 50% had a positive ELISpot response to a single pool of flu, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) (FEC) peptides. This pilot work has been essential in determining the assays and conditions to be used in the correlate study. Moving forward, PBMC will be rested for 2 h before assay setup. The ELISpot assay, performed in duplicate, will be selected over the Ki67 assay, and further work is needed to evaluate the effect of high FEC responses on vaccine-induced immunity and susceptibility to tuberculosis disease.
publisher	American Society for Microbiology
publishDate	2014
url	https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4097435/
_version_	1613113469874208768

Process of Assay Selection and Optimization for the Study of Case and Control Samples from a Phase IIb Efficacy Trial of a Candidate Tuberculosis Vaccine, MVA85A

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