Immunoglobulin G4-related immune responses to common food antigens in patients with ulcerative colitis and Crohn's disease

Association Between Inflammatory Bowel Disease and Viral Infections

Chronic inflammatory gastrointestinal diseases such as Crohn's disease (CD) and ulcerative colitis (UC) are known as inflammatory bowel disorders (IBD). Patients with inflammatory bowel illnesses are more susceptible to viral infections. In people with IBD, viral infections have emerged as a significant issue. Viral infections are often difficult to identify and have a high morbidity and fatality rate. We reviewed studies on viral infections and IBD, concentrating on Cytomegalovirus (CMV), SARS-CoV-2, Epstein-Barr virus (EBV), enteric viruses, and hepatitis B virus (HBV). Also, the effect of IBD on these viral infections is discussed. These data suggest that patients with IBD are more likely to get viral infections. As a result, practitioners should be aware of the increased risk of viral infections in inflammatory bowel disease patients.

New Insights on CD8+ T Cells in Inflammatory Bowel Disease and Therapeutic Approaches

CD8⁺ T cells are involved in the pathogenesis of inflammatory bowel disease (IBD), a complex multifactorial chronic disease. Here, we present an overview of the current research with the controversial findings of CD8⁺ T cell subsets and discuss some possible perspectives on their therapeutic value in IBD. Studies on the role of CD8⁺ T cells in IBD have contradictory outcomes, which might be related to the heterogeneity of the cells. Recent data suggest that cytotoxic CD8⁺ T cells (Tc1) and interleukin (IL) 17-producing CD8⁺ (Tc17) cells contribute to the pathogenesis of IBD. Moreover, subsets of regulatory CD8⁺ T cells are abundant at sites of inflammation and can exhibit pro-inflammatory features. Some subsets of tissue resident memory CD8⁺ T cells (Trm) might be immunosuppressant, whereas others might be pro-inflammatory. Lastly, exhausted T cells might indicate a positive outcome for patients. The function and plasticity of different subsets of CD8⁺ T cells in health and IBD remain to be further investigated in a challenging field due to the limited availability of mucosal samples and adequate controls.