The association of decreased HLA-G+ immune cell frequencies with critical COVID-19 patients.

INTRODUCTION: COVID-19 (coronavirus disease-2019) is an infectious disease caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Immune dysregulation causes inflammation and massive production of inflammatory mediators that worsen the patients' status. Here, regulatory immune cells may ameliorate inflammation and improve the severity of the disease. MATERIALS AND METHODS: A total of 76 participants were enrolled in this study and divided into 3 groups as follows: patients with moderate/severe COVID-19 (n = 25), patients with critical COVID-19 (n = 26), and healthy controls (n = 25). After blood collection, peripheral blood mononuclear cells (PBMCs) were isolated and stained by FITC-conjugated anti-CD4 monoclonal antibodies (mABs), PE-conjugated anti-HLA-G mABs, PerCPCy5.5-conjugated anti-CD14 mABs, and APC-conjugated anti-CD8 mABs. RESULTS: Critical COVID-19 patients had a significantly lower frequency of CD4+ HLA-G+ T lymphocytes compared with moderate/severe COVID-19 patients (p value < 0.001; SMD, -1.27; 95% CI [-1.86, -0.66]) and healthy controls (p value < 0.05; SMD, -0.69; 95% CI [-1.25, -0.12]). Critical COVID-19 patients had a significantly lower frequency of CD14+ HLA-G+ monocytes compared with moderate/severe COVID-19 patients (p value < 0.001; SMD, -2.09; 95% CI [-2.77, -1.41]) and healthy controls (p value < 0.05; SMD, -0.83; 95% CI [-1.40, -0.25]). However, there was no difference between the groups regarding the frequency of CD8+ HLA-G+ T lymphocytes. CONCLUSION: The increased amount of immunomodulatory HLA-G+ cells may reduce the severity of the disease in moderate/severe COVID-19 patients compared with critical COVID-19 patients.

Linkage of Lambda Interferons in Protection Against Severe COVID-19.

The most recently discovered interferon (IFN) family, type III IFNs or lambda IFNs (IFN-λs) are caused by viral infection and act in mucosal barriers, such as the respiratory tract. In this study, we assessed the serum levels of IFN-λs in new coronavirus disease-2019 (COVID-19) patients. Sixty-four COVID-19 patients were enrolled in this study. All cases were divided into the intensive care unit (ICU) and non-ICU groups according to their symptoms. Fourteen samples of healthy controls were also included. The serum levels of IFN-λ1 and IFN-λ2 were analyzed by specific enzyme-linked immunosorbent assay (ELISA) kits. The concentrations of IFN-λ1 and IFN-λ2 induced in the serum of non-ICU patients (836.7 ± 284.6 and 798.8 ± 301.5 pg/mL, respectively) were higher than found in ICU patients (81.57 ± 34.25 and 48.32 ± 28.13 pg/mL, respectively) (P = 0.004 and P = 0.006, respectively) and healthy controls (85.57 ± 33.63 and 65.82 ± 21.26 pg/mL, respectively) (P = 0.03 and P = 0.04, respectively). Meanwhile, no significant differences were found in the concentration of both cytokines between the ICU patients and healthy controls. We conclude that higher levels of IFN-λs are associated with decreased clinical manifestations in COVID-19 patients. These cytokines could be a promising therapeutic agent to avoid the overwhelming consequences of COVID-19.

An investigation of risk factors of in-hospital death due to COVID-19: a case-control study in Rasht, Iran.

BACKGROUND: Identifying the non-survived patients' characteristics compared to survived subjects and introducing the critical risk factors of COVID-19 mortality would help enhance patients' prognosis and treatment. METHODS: In the current case-control study, medical records of 103 non-survived COVID-19 patients (cases) and 147 sex-matched survivors (controls) who admitted to Razi University Hospital in Rasht, Guilan, Northern Iran from April 21 to August 21, 2020, were explored. Data on demographic, anthropometric, clinical, and laboratory assessment was extracted from the electronic medical records. To estimate the association between variables of interest and mortality odds due to COVID-19 logistic regression was carried out. RESULTS: The patients who died (mean age = 62.87 years) were older than the discharged patients (57.33 years; P value = 0.009). According to the results of multivariable regression adjusted for potential confounders, elevated BMI (OR = 2.49; 95% CI = 1.15-5.41), higher CRP levels (OR = 2.28; 95% CI = 1.08-4.78), increased FBS levels (OR = 2.88; 95% CI = 1.35-6.17), higher levels of total cholestrol (OR = 2.55; 95% CI = 1.19-5.45) and LDL (OR = 2.27; 95% CI = 1.07-4.79), elevated triglyceride (OR = 5.14; 95% CI = 2.28-11.56), and raised levels of D-dimer (OR = 5.68; 95% CI = 2.22-14.49) were identified as independent risk factors of COVID-19 mortality. No significant association was detected regarding HDL level, QTc interval or heart size, and COVID-19 fatality odds. CONCLUSION: The present findings demonstrated that obesity, higher levels of CRP, blood sugar, D-dimer, and lipid markers were likely to be predictive factors of COVID-19-related mortality odds.