Elevated CD39+T-Regulatory Cells and Reduced Levels of Adenosine Indicate a Role for Tolerogenic Signals in the Progression from Moderate to Severe COVID-19.

Viral infections trigger inflammation by controlling ATP release. CD39 ectoenzymes hydrolyze ATP/ADP to AMP, which is converted by CD73 into anti-inflammatory adenosine (ADO). ADO is an anti-inflammatory and immunosuppressant molecule which can enhance viral persistence and severity. The CD39-CD73-adenosine axis contributes to the immunosuppressive T-reg microenvironment and may affect COVID-19 disease progression. Here, we investigated the link between CD39 expression, mostly on T-regs, and levels of CD73, adenosine, and adenosine receptors with COVID-19 severity and progression. Our study included 73 hospitalized COVID-19 patients, of which 33 were moderately affected and 40 suffered from severe infection. A flow cytometric analysis was used to analyze the frequency of T-regulatory cells (T-regs), CD39+ T-regs, and CD39+CD4+ T-cells. Plasma concentrations of adenosine, IL-10, and TGF-ß were quantified via an ELISA. An RT-qPCR was used to analyze the gene expression of CD73 and adenosine receptors (A1, A2A, A2B, and A3). T-reg cells were higher in COVID-19 patients compared to healthy controls (7.4 ± 0.79 vs. 2.4 ± 0.28; p < 0.0001). Patients also had a higher frequency of the CD39+ T-reg subset. In addition, patients who suffered from a severe form of the disease had higher CD39+ T-regs compared with moderately infected patients. CD39+CD4+ T cells were increased in patients compared to the control group. An analysis of serum adenosine levels showed a marked decrease in their levels in patients, particularly those suffering from severe illness. However, this was paralleled with a marked decline in the expression levels of CD73. IL-10 and TGF-ß levels were higher in COVID-19; in addition, their values were also higher in the severe group. In conclusion, there are distinct immunological alterations in CD39+ lymphocyte subsets and a dysregulation in the adenosine signaling pathway in COVID-19 patients which may contribute to immune dysfunction and disease progression. Understanding these immunological alterations in the different immune cell subsets and adenosine signaling provides valuable insights into the pathogenesis of the disease and may contribute to the development of novel therapeutic approaches targeting specific immune mechanisms.

Body Mass Index as a Major Prognostic Contributing Factor in COVID-19: A Multicentral Egyptian Study.

Background: Extreme body mass index (BMI) is an influential pathophysiological risk factor for serious illnesses following lower respiratory tract infection. The purpose of the current study was to examine how the BMI of Coronavirus disease-19 (COVID-19) patients affects their prognosis. Methods: Two hundred patients with COVID-19 admitted to Al-Azhar, Qena, Aswan, and Sohag University hospitals in Egypt were included and categorized into four groups according to their BMI. The diagnosis was made according to a real-time reverse transcription-polymerase chain reaction (rRT-PCR) positive result for the SARS-CoV-2 nucleic acid in swabs from upper respiratory tract. A detailed history, clinical examination, and outcomes (disease severity and complications, hospital stay, ICU admission, mortality) were recorded for all patients. SPSS version 24 software was used for data analysis. Results: Average age of participants (19-90 years old), 92 (46%) males and 108 females (54%). ICU admission was significantly higher among underweight patients (75%) and obese patients (78.6%). The majority of underweight (62.5%) and obese (57.1%) patients had critical disease. Invasive mechanical ventilation (MV) is frequently used in underweight (50%) and obese patients (42.9%) patients. Adult respiratory distress syndrome (ARDS), cardiac, neurological, and hematological complications, and incidence of myalgia and bed sores were most frequent among obese and overweight patients. Acute kidney injury was significantly higher among underweight patients (37.5%) and obese patients (28.6%) than among other classes (p=0.004). Frequency of endocrine complications was significantly higher in underweight patients than that in other classes (p=0.01). The majority of underweight (75%) and obese patients (50%) deteriorated and died, whereas the majority of normal-weight patients (90.3%) and overweight patients (75.8%) improved and were discharged (p< 0.001). Conclusion: Body mass index is a major contributing factor to the outcome of patients with COVID-19, and patients with extreme of body mass index were associated with the worst prognosis.

First Report on Abnormal Renal Function in Acute Hepatitis E Genotype 1 Infection.

Impaired renal functions have been reported with Hepatitis E virus (HEV) infections, especially with genotypes 3 and 4. These complications were reported during the acute and chronic phases of infection. HEV genotype 1 causes acute infection, and the effect of HEV-1 infections on renal functions is not known. We examined the kidney function parameters in the serum of HEV-1 patients (AHE, n = 31) during the acute phase of infection. All of the included patients developed an acute self-limiting course of infection, without progression to fulminant hepatic failure. We compared the demographic, laboratory, and clinical data between AHE patients with normal kidney function parameters and those with abnormal renal parameters. Out of 31 AHE patients, 5 (16%) had abnormal kidney function tests (KFTs) during the acute phase of infection. Three patients had abnormal serum urea and creatinine, and two patients had either abnormal urea or creatinine. Four out of five patients had an estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m2. AHE patients with abnormal KFTs were older and had a lower level of albumin, but a slightly elevated alanine transaminase (ALT) compared to AHE patients with normal KFTs. There were no significant differences between the two groups in terms of age, sex, liver transaminase levels, and the viral load. Similarly, the clinical presentations were comparable in both groups. Interestingly, these KFTs in patients with abnormal renal parameters returned to normal levels at the recovery. The serum creatinine level was not correlated with patients' age or liver transaminase levels, but it was significantly negatively correlated with albumin level. In conclusion, this study is the first report that evaluated KFTs in patients during the acute phase of HEV-1 infections. Impaired KFTs in some AHE patients resolved at convalescence. KFTs and renal complications should be monitored during HEV-1 infections.

Non-alcoholic fatty liver disease is associated with decreased bone mineral density in upper Egyptian patients.

Nonalcoholic fatty liver disease (NAFLD) has been linked with a number of extra hepatic diseases and could be a potential risk factor of decreasing bone mineral density. To determine whether Upper Egyptian patients with NAFLD are at risk of developing osteoporosis. Cross sectional study was done on a total 100 individuals; 50 patients diagnosed with NAFLD (based on ultrasound imaging) crossed-matched with 50 individuals without NAFLD based on age, sex and body mass index. Bone mineral density, serum calcium and phosphorus levels, serum parathyroid hormone, serum vitamin D and fasting insulin level were assessed. Osteoporosis was prevalent in NAFLD patients versus to controls (19/50 vs. 0/50; P < 0.001). There was significant decrease in bone mineral density in NAFLD patients than controls (- 2.29 ± 0.4 vs. - 1.53 ± 0.1; P < 0.001). There was a statistical significance decrease in serum vitamin D and calcium levels in NAFLD patients than controls. Furthermore, vitamin D levels in the NAFLD group was a predictor for osteoporosis (OR 0.614; 95% CI 0.348-0.825). Patients with NAFLD tend to have a significant decrease in bone density, vitamin D, and serum calcium levels than controls.