PURPOSE: About 15% of patients with common variable immunodeficiency (CVID) develop a small intestinal enteropathy, which resembles celiac disease with regard to histopathology but evolves from a distinct, poorly defined pathogenesis that has been linked in some cases to chronic norovirus (NV) infection. Interferon-driven inflammation is a prominent feature of CVID enteropathy, but it remains unknown how NV infection may contribute. METHODS: Duodenal biopsies of CVID patients, stratified according to the presence of villous atrophy (VA), IgA plasma cells (PCs), and chronic NV infection, were investigated by flow cytometry, multi-epitope-ligand cartography, bulk RNA-sequencing, and RT-qPCR of genes of interest. RESULTS: VA development was connected to the lack of intestinal (IgA+) PC, a T helper 1/T helper 17 cell imbalance, and increased recruitment of granzyme+CD8+ T cells and pro-inflammatory macrophages to the affected site. A mixed interferon type I/III and II signature occurred already in the absence of histopathological changes and increased with the severity of the disease and in the absence of (IgA+) PCs. Chronic NV infection exacerbated this signature when compared to stage-matched NV-negative samples. CONCLUSIONS: Our study suggests that increased IFN signaling and T-cell cytotoxicity are present already in mild and are aggravated in severe stages (VA) of CVID enteropathy. NV infection preempts local high IFN-driven inflammation, usually only seen in VA, at milder disease stages. Thus, revealing the impact of different drivers of the pathological mixed IFN type I/III and II signature may allow for more targeted treatment strategies in CVID enteropathy and supports the goal of viral elimination.

• Klíčová slova
• CVID, Cytotoxic T cell response, Duodenum, Interferon response genes, Norovirus, Villous atrophy,
• MeSH
• atrofie komplikace   patologie   MeSH
• běžná variabilní imunodeficience * komplikace   imunologie   MeSH
• CD8-pozitivní T-lymfocyty MeSH
• imunoglobulin A MeSH
• infekce viry z čeledi Caliciviridae * imunologie   MeSH
• interferony MeSH
• lidé MeSH
• Norovirus * fyziologie   MeSH
• zánět komplikace   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• imunoglobulin A MeSH
• interferony MeSH