Shift to Th2; reduced IFN-γ, increased IL-4 & IL-10. CD4+ helper cells can partially compensate via glycolytic reprogramming, resulting in less pronounced quantitative loss.
Impaired methylation-dependent stability of FOXP3 expression → impaired Treg differentiation → loss of peripheral tolerance; disproportionately affected due to constitutive methylation-dependence of FOXP3 expression.
Impact of vitamin B12 deficiency on lymphocyte subsets and humoral immunity. FOXP3: forkhead box P3; Treg: regulatory T cell.
Declarations
Acknowledgments
AI-Assisted Work Statement: During the preparation of this work, author(s) used ChatGPT for assistance in generating Figure 1. After using the tool, author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the publication.
The authors wish to sincerely thank the patients and clinicians of the Strasbourg B12 research group (CARE B12) at the Hôpitaux Universitaires de Strasbourg (HUS, France) for their invaluable contributions to this study.
Author contributions
EA: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. NLV: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. TL: Validation, Writing—review & editing, Supervision. All authors read and approved the submitted version.
Open Exploration maintains a neutral stance on jurisdictional claims in published institutional affiliations and maps. All opinions expressed in this article are the personal views of the author(s) and do not represent the stance of the editorial team or the publisher.
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