Overview of Three Proliferation Pathways (Wnt, Notch, and Hippo) in Intestine and Immune System and Their Role in Inflammatory Bowel Diseases (IBDs).

Inflammatory bowel disease (IBD) is a disorder, which involves the gastrointestinal (GI) tract consisting Crohn's disease (CD) and ulcerative colitis (UC). The etiology of this disease is not yet clear and, hence, there are numerous medications and treatments for patients with IBD, although a definite and permanent treatment is still missing. Therefore, finding novel therapeutic approaches are vital for curing patients with IBD. In the GI tract, there are various lineages of cells with different roles that their existence is necessary for the barrier function of intestinal epithelial cells (IECs). Therefore, signaling pathways, which manage the hemostasis of cell lineages in intestine, such as Wnt, Notch, and Hippo, could have crucial roles in regulation of barrier function in the intestine. Additionally, these signaling pathways function as a governor of cell growth, tissue homeostasis, and organ size. In patients with IBD, recent studies have revealed that these signaling pathways are dysregulated that it could result in depletion or excess of a cell lineage in the intestine. Moreover, dysregulation of these signaling pathways in different cell lineages of the immune system could lead to dysregulation of the immune system's responses in IBD. In this article, we summarized the components and signaling of Wnt, Notch, and Hippo pathways and their role in the intestine and immune system. Furthermore, we reviewed latest scientific literature on the crosstalk among these three signaling pathways in IBD. An overview of these three signaling pathways and their interactions in IBD could provide a novel insight for prospective study directions into finding efficient medications or treatments.

High prevalence of SARS-Coronavirus-2 in patients with inflammatory bowel disease and the role of soluble angiotensin converting Enzyme2.

Context: Patients with inflammatory bowel disease (IBD) were found to have the higher intestinal expression of Angiotensin-Converting Enzyme2 (ACE2) that could consequently increase susceptibility to COVID-19 infection.Objective: This study reports the outcomes of COVID-19 infection in a large cohort of IBD patients. We compare levels of serum ACE and IFN-α between COVID19 patients with and without IBD. We performed a cross-sectional retrospective multicenter study.Methods: We enrolled patients with IBD screened for SARS-COV-2 in six medical centres in Iran from June to November 2020. The blood samples were drawn to measure COVID-19 IgM and IgG, and serum levels of sACE2, sACE1, and interferon-α, regardless of suspicious symptoms have done the molecular test.Results: A total of 534 IBD patients were included in the study. Of these, 109 (20.0%) cases had detectable IgG and IgM against SARS-CoV-2. sACE2 levels were higher in IBD patients than controls, whereas ACE1and IFN-α levels were similar among groups.

Serological response to SARS-CoV-2 is attenuated in patients with inflammatory bowel disease and can affect immunization.

In this study we indicated that impaired serological responses to SARS-CoV-2 infection among patients with IBD, could have significant implications for this group of patients and should be considered in vaccination program.