AID Activity in B Cells Strongly Correlates with Polyclonal Antibody Affinity Maturation in-vivo Following Pandemic 2009-H1N1 Vaccination in Humans

PLoS Pathogens

Daniela Frasca¹  Bonnie Blomberg¹  Hana Golding²  Surender Khurana² 

[1] Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, Florida, United States of America;Division of Viral Products, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA), Bethesda, Maryland, United States of America

关键词: Vaccination;    immunization;    Antibodies;    B cells;    Antibody affinity;    Vaccines;    Elderly;    Influenza;    Blood plasma;   

DOI  :  10.1371/journal.ppat.1002920

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

The role of Activation-Induced Cytidine Deaminase (AID) in somatic hypermutation and polyclonal antibody affinity maturation has not been shown for polyclonal responses in humans. We investigated whether AID induction in human B cells following H1N1pdm09 vaccination correlated with in-vivo antibody affinity maturation against hemagglutinin domains in plasma of young and elderly individuals. AID was measured by qPCR in B cells from individuals of different ages immunized with the H1N1pdm09 influenza vaccine. Polyclonal antibody affinity in human plasma for the HA1 and HA2 domains of the H1N1pdm09 hemagglutinin was measured by antibody-antigen complex dissociation rates using real time kinetics in Surface Plasmon Resonance. Results show an age-related decrease in AID induction in B cells following H1N1pdm09 vaccination. Levels of AID mRNA before vaccination and fold-increase of AID mRNA expression after H1N1pdm09 vaccination directly correlated with increase in polyclonal antibody affinity to the HA1 globular domain (but not to the conserved HA2 stalk). In the younger population, significant affinity maturation to the HA1 globular domain was observed, which associated with initial levels of AID and fold-increase in AID after vaccination. In some older individuals (>65 yr), higher affinity to the HA1 domain was observed before vaccination and H1N1pdm09 vaccination resulted in minimal change in antibody affinity, which correlated with low AID induction in this age group. These findings demonstrate for the first time a strong correlation between AID induction and in-vivo antibody affinity maturation in humans. The ability to generate high affinity antibodies could have significant impact on the elucidation of age-specific antibody responses following vaccination and eventual clinical efficacy and disease outcome.

【 授权许可】

CC BY