Subject(s)
Central Nervous System/virology , Forkhead Transcription Factors/immunology , SARS-CoV-2/physiology , T-Lymphocytes, Regulatory/immunology , Animals , CD4 Antigens/immunology , COVID-19/complications , COVID-19/immunology , COVID-19/virology , Central Nervous System/immunology , Central Nervous System Diseases/complications , Central Nervous System Diseases/immunology , Central Nervous System Diseases/virology , Humans , Interleukin-2 Receptor alpha Subunit/immunology , Neuropilin-1/immunology , SARS-CoV-2/immunologyABSTRACT
The severe cases of Coronavirus Disease 2019 (COVID-19) frequently exhibit excessive inflammatory responses, acute respiratory distress syndrome (ARDS), coagulopathy, and organ damage. The most striking immunopathology of advanced COVID-19 is cytokine release syndrome or "cytokine storm" that is attributable to the deficiencies in immune regulatory mechanisms. CD4+FoxP3+ regulatory T cells (Tregs) are central regulators of immune responses and play an indispensable role in the maintenance of immune homeostasis. Tregs are likely involved in the attenuation of antiviral defense at the early stage of infection and ameliorating inflammation-induced organ injury at the late stage of COVID-19. In this article, we review and summarize the current understanding of the change of Tregs in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and discuss the potential role of Tregs in the immunopathology of COVID-19. The emerging concept of Treg-targeted therapies, including both adoptive Treg transfer and low dose of IL-2 treatment, is introduced. Furthermore, the potential Treg-boosting effect of therapeutic agents used in the treatment of COVID-19, including dexamethasone, vitamin D, tocilizumab and sarilumab, chloroquine, hydroxychloroquine, azithromycin, adalimumab and tetrandrine, is discussed. The problems in the current study of Treg cells in COVID-19 and future perspectives are also addressed.
Subject(s)
CD4 Antigens/immunology , COVID-19/immunology , COVID-19/therapy , Forkhead Transcription Factors/immunology , T-Lymphocytes, Regulatory/immunology , COVID-19/virology , Cytokine Release Syndrome , Humans , SARS-CoV-2/isolation & purificationABSTRACT
BACKGROUND: We observe changes of the main lymphocyte subsets (CD16+CD56ãCD19ãCD3ãCD4ãand CD8) in COVID-19-infected patients and explore whether the changes are associated with disease severity. METHODS: One-hundred and fifty-four cases of COVID-19-infected patients were selected and divided into 3 groups (moderate group, severe group and critical group). The flow cytometry assay was performed to examine the numbers of lymphocyte subsets. RESULTS: CD3+, CD4+ and CD8 + T lymphocyte subsets were decreased in COVID-19-infected patients. Compared with the moderate group and the sever group, CD3+, CD4+ and CD8+ T cells in the critical group decreased greatly (P < 0.001, P = 0.005 or P = 0.001). CONCLUSIONS: Reduced CD3+, CD4+, CD8+ T lymphocyte counts may reflect the severity of the COVID-19. Monitoring T cell changes has important implications for the diagnosis and treatment of severe patients who may become critically ill.