Porcine Deltacoronavirus Infection Disrupts the Intestinal Mucosal Barrier and Inhibits Intestinal Stem Cell Differentiation to Goblet Cells via the Notch Signaling Pathway.

Goblet cells and their secreted mucus are important elements of the intestinal mucosal barrier, which allows host cells to resist invasion by intestinal pathogens. Porcine deltacoronavirus (PDCoV) is an emerging swine enteric virus that causes severe diarrhea in pigs and causes large economic losses to pork producers worldwide. To date, the molecular mechanisms by which PDCoV regulates the function and differentiation of goblet cells and disrupts the intestinal mucosal barrier remain to be determined. Here, we report that in newborn piglets, PDCoV infection disrupts the intestinal barrier: specifically, there is intestinal villus atrophy, crypt depth increases, and tight junctions are disrupted. There is also a significant reduction in the number of goblet cells and the expression of MUC-2. In vitro, using intestinal monolayer organoids, we found that PDCoV infection activates the Notch signaling pathway, resulting in upregulated expression of HES-1 and downregulated expression of ATOH-1 and thereby inhibiting the differentiation of intestinal stem cells into goblet cells. Our study shows that PDCoV infection activates the Notch signaling pathway to inhibit the differentiation of goblet cells and their mucus secretion, resulting in disruption of the intestinal mucosal barrier. IMPORTANCE The intestinal mucosal barrier, mainly secreted by the intestinal goblet cells, is a crucial first line of defense against pathogenic microorganisms. PDCoV regulates the function and differentiation of goblet cells, thereby disrupting the mucosal barrier; however, the mechanism by which PDCoV disrupts the barrier is not known. Here, we report that in vivo, PDCoV infection decreases villus length, increases crypt depth, and disrupts tight junctions. Moreover, PDCoV activates the Notch signaling pathway, inhibiting goblet cell differentiation and mucus secretion in vivo and in vitro. Thus, our results provide a novel insight into the mechanism underlying intestinal mucosal barrier dysfunction caused by coronavirus infection.

The impact of recent chemotherapy on immunity in 2 COVID-19 cases with gastrointestinal tumors: A case report.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a rapidly emerging infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2. Currently, more than 100 million cases of COVID-19 have been confirmed worldwide, with over 2.4 million mortalities. The pandemic affects people of all ages but older individuals and those with severe chronic illnesses, including cancer patients, are at higher risk. PATIENT CONCERNS: The impact of cancer treatment on the progression of COVID-19 is unclear. Therefore, we assessed the effects of chemotherapy on COVID-19 outcomes for 2 cancer patients. On January 24, 2020, a level I response to a major public health emergency was initiated in Hubei Province, China, which includes Enshi Autonomous Prefecture that has a population of 4.026 million people. As of April 30, 2020, 252 confirmed cases of COVID-19 and 11 asymptomatic carriers were identified in Enshi. DIAGNOSIS: Among the confirmed cases and asymptomatic carriers, 2 patients were identified who were previously diagnosed with malignant tumors, including one with hepatocellular carcinoma and the other with cardia carcinoma. INTERVENTIONS: These 2 patients were receiving or just completed chemotherapy at the time of their COVID-19 diagnosis. OUTCOMES: Both patients were followed and presented favorable outcomes. The positive outcomes for these 2 patients could be partially explained by their recent chemotherapy that impacted their immune status. Also, their relatively younger ages and lack of comorbidities were likely factors in their successful recovery from COVID-19. CONCLUSIONS: Anticancer treatment might enhance a patient's ability to respond favorably to COVID-19 infection. However, anticancer treatment is likely to impact immune function differently in different individuals, which can influence disease outcomes.

A retrospective analysis from a single center for 60 COVID-19 patients with asymptomatic, mild to moderate, and severe conditions in Wuxi, China.

ABSTRACT: The aim of this study was to retrospectively analyze the clinical data of COVID-19 patients with different severity during February 2020 in Wuxi, China.The present retrospective study included a total of 60 cases who were diagnosed as COVID-19 patients and hospitalized in the Wuxi Fifth People's Hospital during February 2020 to March 2020. Among all patients 14 cases were asymptomatic, 25 cases were with mild stage, 13 cases were with moderate stage, and 8 cases were with severe stage. Basic clinical data as well as clinical characteristics, including temperature, respiratory rate, heart rate, blood gas analysis data, whole blood test data, and the prognosis condition, were collected and analyzed. Statistical analysis was conducted in different severity stage patients.Among the patients, the median temperature gradually increased from the asymptomatic to the severe patients and the median age increased from the mild to the severe patients with statistical difference. The hospitalization duration was the highest in severe patients. Higher heart rate, as well as lower oxygen partial pressure and oxygenation index were observed in severe patients than the other groups. Besides, higher CRP and globulin levels after admission were found in severe patients, and were gradually increased from the asymptomatic patients to the severe patients. On the contrary, the lymphocyte ratio and count was significant lower in severe patients. We also observed higher D-Dimer levels in the severe patients and the difference was statistical. Among all patients, 2 cases (3.33%) died and other patients were all cured after treatment.Statistical difference was mainly found mainly in age, hospitalization duration, temperature, CRP levels, O2 partial pressure and oxygenation index, globulin, lymphocyte ratio, and D-Dimer in patients with different severity. The higher CRP levels, lower O2 partial pressure and oxygenation index, higher globulin, lower lymphocyte ratio, and higher D-Dimer might be associated with the patients' severity.