Dysregulated innate epithelial response to norovirus infection in intestinal organoids from patients with common variable immunodeficiency

Magdalena Neijd, Linköping University, Sweden

Magdalena Neijd, Division of Molecular Medicine and Virology, Linköping University, Sweden; Khalil Ettayebi, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA; Hoa Nguyen-Phuc, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA; Xi-Lei Zeng, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA; Åsa Nilsdotter-Augustinsson, Division of Inflammation and Infection, Linköping University, Sweden; Rikard Svernlöv, Department of Gastroenterology and Hepatology, Linköping University, Sweden; Lennart Svensson, Division of Molecular Medicine and Virology, Linköping University, Sweden; Johan Nordgren, Division of Molecular Medicine and Virology, Linköping University, Sweden; Sue E. Crawford, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA; Marie Hagbom, Division of Molecular Medicine and Virology, Linköping University, Sweden; Mary K. Estes, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA

Entry and Replication

Common variable immunodeficiency (CVID) is a primary immune deficiency characterized by impaired B-cell function and reduced immunoglobulin levels, leading to recurrent and long-lasting infections. Norovirus can cause chronic infections in CVID patients, potentially leading to malabsorption and increased mortality. While impaired adaptive immune responses are well-documented in CVID, the role of innate response in gastrointestinal infections is less explored.

To investigate the innate epithelial response, we infected secretor positive human intestinal enteroids from CVID patients (n=4) and immunocompetent individuals (n=2) with norovirus GII.3, GII.4, or stimulated with poly(I:C). Replication was analyzed by RTqPCR and transcriptional responses by whole genome RNA sequencing (RNA-Seq). No significant difference was seen in norovirus replication between CVID and immunocompetent enteroids, or in epithelial response observed after poly (I:C) stimulation. However, the RNA-Seq revealed that immunocompetent enteroids infected with GII.4 upregulated antiviral pathways while CVID enteroids exhibited responses mainly related to metabolic pathways. Several genes important for innate immune response, such as IFITM1, ZBP1, IFIT1 and HERC5, were significantly upregulated in immunocompetent but not in CVID enteroids. In contrast, GII.3 infection upregulated immune-specific genes and pathways in both CVID and immunocompetent enteroids, but the response was substantially lower in CVID.

Altogether, our study identifies several key differences in the epithelial response to norovirus infection, suggesting that an impaired innate immune response may contribute to more severe and prolonged norovirus infection in CVID patients.