Peripheral innate and adaptive immune cells during COVID-19: Functional neutrophils, pro-inflammatory monocytes, and half-dead lymphocytes.

BACKGROUND: A better understanding of innate and adaptive cells in COVID-19 is necessary for the development of effective treatment methods and vaccines. METHODS: We studied phenotypic features of innate and adaptive immune cells, oxidative burst, phagocytosis, and apoptosis. One hundred and three patients with COVID-19 were grouped according to their clinical features into the categories of mild (35%), moderate (40.8%), and severe (24.3%). RESULTS: Monocytes were CD16+ pro-inflammatory monocytes and tended to shed their HLA-DR, especially in severe cases (p < 0.01). Neutrophils were mature and functional, although a decline of their CD10 and CD16 was observed (p < 0.01). No defect was found in the reactive oxygen species production and their apoptosis. The percentage of natural killer cells was in the normal range, whereas the percentages of CD8+ NK and CD56+ T lymphocytes were found to be high (p < 0.01). Although the absolute numbers of all lymphocyte subsets were low and showed a tendency for a gradual decrease in accordance with the disease progression, the most decreased absolute number was that of B lymphocytes, followed by CD4+ T cells in the severe cases. The percentages of double-negative T cells; HLA-DR+ CD3+ and CD28- CD8+ subsets were found to be significantly increased. Importantly, we demonstrated the increased baseline activation of caspase-3 and increased lymphocyte apoptosis. CONCLUSION: We suggest that SARS-CoV-2 primarily affects the lymphocytes and not the innate cells. The increased baseline activation of Caspase-3 could make the COVID-19 lymphocytes more vulnerable to cell death. Therefore, this may interrupt the crosstalk between the adaptive and innate immune systems.

The impact of ultrasonography-guided fine needle aspiration of no palpable supraclavicular lymph nodes on diagnosis and staging in advanced lung cancer.

Diagnosis and accurate staging of lung cancer is essential for selection of appropriate curative or palliative therapy and affects patient prognosis. Both invasive and non-invasive procedures are used for this purpose. We aimed to assess the frequency of no palpable supraclavicular lymph node metastases in lung cancer patients with enlarged mediastinal lymph nodes, and their impact on diagnosis and staging using ultrasound in this study. Lung cancer patients with no palpable supraclavicular lymph nodes and at least 2 enlarged mediastinal lymph nodes on computerized tomography underwent supraclavicular ultrasound examination. Ultrasound-guided fine needle aspiration (US-guided FNA) was performed when enlarged lymph nodes were present. Supraclavicular lymph node metastasis was confirmed cytologically via US-guided FNA in 16 (40%) of 40 patients. Upper paratracheal lymphadenomegaly was significantly higher in patients with supraclavicular metastases than in those without. No statistical significant differences were observed in the stage, cell types, and metastases of patients with or without supraclavicular metastases. In 3 patients US-guided FNA was used for diagnosis. More than one-third of lung cancer patients with enlarged mediastinal lymph nodes had supraclavicular lymph node metastases in present study. US-guided FNA is an easier, safer, and less invasive procedure than standard techniques used to diagnose lung cancer patients with enlarged mediastinal lymph nodes.