ABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) is affecting the whole world and threatening human health. We aim to investigate the immunological characteristics of monocytes in critical patients with COVID-19. METHODS: The number and immune status of monocytes were detected by flow cytometry in 32 COVID-19 patients and 18 healthy individuals. RESULTS: In critical patients with COVID-19, the absolute number of total monocytes and CD16- monocytes was significantly decreased but CD16+ pro-inflammatory monocytes was increased compared to healthy controls. Antigen presentation potential of monocytes, as measured by HLA-DR expression, was suppressed, while their inflammatory phenotype (CD38 expression) was enhanced. Cytokine levels showed sustained increases in critical patients. And the levels of IL-6 were positively correlated with CD16+ monocytes number. IL-6 and IL-10 levels were negatively correlated with HLA-DR expression of monocytes. During the recovery of COVID-19 patients, the count and immune status of monocyte subsets were restored by degrees. HLA-DR+ monocytes possessed good sensitivity and specificity for predicting the incidence of critical patients with COVID-19. CONCLUSIONS: In critical patients with COVID-19, decline in number and HLA-DR expression of monocytes might lead to decreased antigen presentation potential and thus immunosuppression, while increased CD16+ pro-inflammatory monocytes might mediate hyperinflammation. HLA-DR+ monocytes might be a meaningful assisted indicator to predict the incidence of critical patients with COVID-19.
Subject(s)
COVID-19/immunology , Monocytes/immunology , ADP-ribosyl Cyclase 1/immunology , Aged , Antigen Presentation , COVID-19/blood , Case-Control Studies , Cytokines/immunology , Female , Flow Cytometry , HLA-DR Antigens/immunology , Humans , Inflammation/immunology , Male , Middle Aged , Phenotype , Receptors, IgG/immunologyABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) is posing a huge threat to human health worldwide. We aim to investigate the immune status of CD8+ T and NK cells in COVID-19 patients. METHODS: The count and immune status of lymphocytes were detected by flow cytometry in 32 COVID-19 patients and 18 healthy individuals. RESULTS: As the disease progression in COVID-19 patients, CD8+ T and NK cells were significantly decreased in absolute number but highly activated. After patients' condition improved, the count and immune status of CD8+ T and NK cells restored to some extent. GrA+CD8+ T and perforin+ NK cells had good sensitivity and specificity for assisting diagnosis of COVID-19. CONCLUSIONS: As the disease progression, the declined lymphocytes in COVID-19 patients might lead to compensatory activation of CD8+ T and NK cells. GrA+CD8+ T and perforin+ NK cells might be used as meaningful indicators for assisting diagnosis of COVID-19.
Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/diagnosis , Granzymes/genetics , Killer Cells, Natural/immunology , Perforin/genetics , Pneumonia, Viral/diagnosis , T-Lymphocytes, Cytotoxic/immunology , Aged , Aged, 80 and over , Betacoronavirus/immunology , Biomarkers/blood , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , CD4-Positive T-Lymphocytes/virology , COVID-19 , COVID-19 Testing , Case-Control Studies , China , Clinical Laboratory Techniques/methods , Coronavirus Infections/blood , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Disease Progression , Female , Gene Expression , Granzymes/blood , Granzymes/immunology , Humans , Killer Cells, Natural/pathology , Killer Cells, Natural/virology , Lymphocyte Activation , Lymphocyte Count , Male , Middle Aged , Pandemics , Perforin/blood , Perforin/immunology , Pneumonia, Viral/blood , Pneumonia, Viral/immunology , Pneumonia, Viral/pathology , Prognosis , ROC Curve , SARS-CoV-2 , Severity of Illness Index , T-Lymphocytes, Cytotoxic/pathology , T-Lymphocytes, Cytotoxic/virologyABSTRACT
BACKGROUND: COVID-19 is threating human health worldwide. We aim to investigate the dynamic changes of immune status in COVID-19 patients with clinical evolution. METHODS: Sixty-one COVID-19 patients (42 mild cases and 19 severe cases, 51 cases without secondary infection as non-infection group and 10 cases with secondary bacterial/fungal infection as infection group) and 52 healthy controls (HCs) were enrolled from our hospital. Leucocyte classification, lymphocyte subsets and cytokines were detected by full-automatic blood cell analyzer and flow cytometer, respectively. RESULTS: Upon admission, eosinophils and lymphocyte subsets decreased significantly, while neutrophils, monocytes, basophils, IL-2, IL-6, IL-10 and IFN-γ increased significantly in COVID-19 patients compared to HCs. CD3+ T and DN (CD3+CD4-CD8-) cells appeared sustained decline, leucocytes, neutrophils and IL-10 showed sustained increase in severe group compared to mild group. Compared with the non-infection group, we observed a depletion of eosinophils, CD3+ T and CD4+ T cells, but leucocytes, neutrophils, IL-6 and IL-10 on the contrary in the infection group. Besides, in severe group of COVID-19 patients, DN cells were negatively correlated with IL-10, and DP (CD3+CD4+CD8+) cells were negatively correlated with IL-6. Lymphocytes, eosinophils, CD3+ T cells, CD4+ T cells, IL-6 and IL-10 all had great diagnostic efficacy (AUC, 0.905-0.975) for COVID-19. The laboratory indicators of COVID-19 patients with improved condition also showed a recovery trend with time. CONCLUSIONS: The immune status of COVID-19 patients is different in each stage, and dynamic monitoring of related indicators can help predict the disease and may avoid cytokine storms.