Science and Research Branch, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran.
Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Arch Iran Med. 2022 Feb 1;25(2):127-132. doi: 10.34172/aim.2022.22.
Severe cases of coronavirus disease 2019 (COVID-19) often experience hyper-inflammatory reactions, acute respiratory distress syndrome (ARDS), blood clotting, and organ damage. The most prominent immunopathology of advanced COVID-19 is cytokine release syndrome, or "cytokine storm" which is attributed to a defect of immune-regulating mechanisms. This study aimed to evaluate the role of regulatory T cells (Tregs) as one of the main cells that maintain immune homeostasis.
A systematic search was performed on PubMed, Scopus and Google Scholar. All English articles related to Treg's role in COVID-19 were extracted and evaluated by two researchers independently. Study eligibility was assessed based on modified Evidence-based librarianship (EBL) checklist.
Nineteen eligible studies comparing Treg cells in COVID-19 patients with the control group or comparing alterations of this cell in severe and moderate patients were evaluated. Currently, there is no consensus regarding the increase or decrease of Tregs in COVID-19 patients compared to the control group. However, it was observed that Tregs in severe COVID-19 patients were significantly lower than moderate patients, resulting in uncontrolled inflammation and cytokine storm.
Regulatory T cells can be one of the determinants of disease severity and prognosis in patients with COVID-19 by inhibiting rampant inflammation and preventing cytokine storms.
严重的 2019 冠状病毒病（COVID-19）病例常经历过度炎症反应、急性呼吸窘迫综合征（ARDS）、凝血和器官损伤。COVID-19 晚期最突出的免疫病理学表现为细胞因子释放综合征，或“细胞因子风暴”，这归因于免疫调节机制的缺陷。本研究旨在评估调节性 T 细胞（Treg）作为维持免疫稳态的主要细胞之一的作用。
在 PubMed、Scopus 和 Google Scholar 上进行了系统检索。提取并由两名研究人员独立评估了所有与 Treg 在 COVID-19 中的作用相关的英文文章。根据改良的循证图书馆学（EBL）检查表评估研究的合格性。
评估了 19 项比较 COVID-19 患者与对照组 Treg 细胞或比较重症和轻症患者该细胞变化的合格研究。目前，与对照组相比，COVID-19 患者 Treg 细胞是否增加或减少尚无共识。然而，观察到重症 COVID-19 患者的 Treg 细胞明显低于轻症患者，导致炎症失控和细胞因子风暴。
调节性 T 细胞可通过抑制过度炎症和预防细胞因子风暴成为 COVID-19 患者疾病严重程度和预后的决定因素之一。
