IMMUNOLOGY2026™ Conference Recordings For Attendees-Immune Cell Derived 1,25(OH)2D3: A Critical Defense Against Influenza Infection

Immune Cell Derived 1,25(OH)2D3: A Critical Defense Against Influenza Infection

Video Transcription

Video Summary

Nicole Froehlich described research on how immune cells locally produce active vitamin D (1,25D) via the enzyme CYP27B1 to protect against influenza A infection. She explained that while circulating vitamin D status is usually measured by 25D, immune cells can also activate vitamin D locally, especially after activation. Using mouse models, her lab compared wild type mice, whole-body CYP27B1 knockouts, kidney-specific knockouts (DECO), and T cell-specific knockouts. Whole-body knockouts had worse illness, higher viral loads, reduced CD8 T cell granzyme B responses, and increased lethality. In contrast, DECO mice, which lacked renal but not immune-cell CYP27B1, showed no major illness difference from wild type, indicating local rather than systemic vitamin D activation was key. T cell-specific knockouts had worse symptoms and reduced CD8 cytotoxic function, highlighting an important T cell role. She concluded that local vitamin D metabolism in immune cells supports antiviral immunity and may inform future supplementation strategies.

Meta Tag

Date April 16, 2026 1:30 PM - 1:45 PM

Room 104AB

Session CD8+ T Cell and NK Cell Mediated Antiviral Immunity

Speaker Nicole Froelich

Track Viral Immunology (VIR)

Year 2026

Keywords

vitamin D

CYP27B1

influenza A

immune cells

CD8 T cells

April 16, 2026 1:30 PM - 1:45 PM

104AB

CD8+ T Cell and NK Cell Mediated Antiviral Immunity

Nicole Froelich

Viral Immunology (VIR)

2026