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How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections

BACKGROUND: The germinal center (GC) reaction leads to antibody affinity maturation and generation of memory B cells, but its underlying mechanisms are poorly understood. To assemble this puzzle, several key pieces of information are needed, one in particular being the number of participating B cell...

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Autores principales: Faro, Jose, Or-Guil, Michal
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3633029/
https://www.ncbi.nlm.nih.gov/pubmed/23734629
http://dx.doi.org/10.1186/1471-2105-14-S6-S8
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author Faro, Jose
Or-Guil, Michal
author_facet Faro, Jose
Or-Guil, Michal
author_sort Faro, Jose
collection PubMed
description BACKGROUND: The germinal center (GC) reaction leads to antibody affinity maturation and generation of memory B cells, but its underlying mechanisms are poorly understood. To assemble this puzzle, several key pieces of information are needed, one in particular being the number of participating B cell clones. Since this clonal diversity cannot be observed directly, earlier studies resorted to interpreting two types of available experimental data: Immunohistology of GCs containing two phenotypically distinct B-cell populations, and antibody gene sequences of small B-cell samples from GCs. Based on a simple model, investigators concluded that a typical GC was seeded by 2-8 B cells, endorsing the current notion that GCs are oligoclonal from the onset. RESULTS: A re-evaluation of these data showed that the used simple model is not statistically consistent with the original data. From an analysis of the experimental system, we propose a new model for estimating GC clonal diversity, including the initially neglected sampling and measurement errors, and making more general assumptions. Consistency analysis with the new model yielded an estimation of sampling and measurement errors in the experimental data of 10-11% for one B-cell population and 62-64% for the other population, and an average number of 19-23 seeder B cells. An independent analysis of antibody gene sequences of small B-cell samples from GCs, using an adapted Yule estimator of diversity, yielded a minimum estimation of 20-30 GC founder B cells, confirming the previous results. CONCLUSIONS: Our new experimental-based model provides a highly improved method to estimate the clonal diversity of GCs from inmunohistochemistry data of chimeric animals. Calculations based on this model, and validated by an independent approach, indicate that GCs most likely contain broadly varying numbers of different B cell clones, averaging 5- to 10-fold more clones than previously estimated. These findings, in line with recent results showing that GC sizes and life times are also subject to high variability, dramatically change the picture of GC dynamics.
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spelling pubmed-36330292013-04-25 How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections Faro, Jose Or-Guil, Michal BMC Bioinformatics Proceedings BACKGROUND: The germinal center (GC) reaction leads to antibody affinity maturation and generation of memory B cells, but its underlying mechanisms are poorly understood. To assemble this puzzle, several key pieces of information are needed, one in particular being the number of participating B cell clones. Since this clonal diversity cannot be observed directly, earlier studies resorted to interpreting two types of available experimental data: Immunohistology of GCs containing two phenotypically distinct B-cell populations, and antibody gene sequences of small B-cell samples from GCs. Based on a simple model, investigators concluded that a typical GC was seeded by 2-8 B cells, endorsing the current notion that GCs are oligoclonal from the onset. RESULTS: A re-evaluation of these data showed that the used simple model is not statistically consistent with the original data. From an analysis of the experimental system, we propose a new model for estimating GC clonal diversity, including the initially neglected sampling and measurement errors, and making more general assumptions. Consistency analysis with the new model yielded an estimation of sampling and measurement errors in the experimental data of 10-11% for one B-cell population and 62-64% for the other population, and an average number of 19-23 seeder B cells. An independent analysis of antibody gene sequences of small B-cell samples from GCs, using an adapted Yule estimator of diversity, yielded a minimum estimation of 20-30 GC founder B cells, confirming the previous results. CONCLUSIONS: Our new experimental-based model provides a highly improved method to estimate the clonal diversity of GCs from inmunohistochemistry data of chimeric animals. Calculations based on this model, and validated by an independent approach, indicate that GCs most likely contain broadly varying numbers of different B cell clones, averaging 5- to 10-fold more clones than previously estimated. These findings, in line with recent results showing that GC sizes and life times are also subject to high variability, dramatically change the picture of GC dynamics. BioMed Central 2013-04-17 /pmc/articles/PMC3633029/ /pubmed/23734629 http://dx.doi.org/10.1186/1471-2105-14-S6-S8 Text en Copyright © 2012 Faro and Or-Guil; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Proceedings
Faro, Jose
Or-Guil, Michal
How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title_full How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title_fullStr How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title_full_unstemmed How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title_short How oligoclonal are germinal centers? A new method for estimating clonal diversity from immunohistological sections
title_sort how oligoclonal are germinal centers? a new method for estimating clonal diversity from immunohistological sections
topic Proceedings
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3633029/
https://www.ncbi.nlm.nih.gov/pubmed/23734629
http://dx.doi.org/10.1186/1471-2105-14-S6-S8
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