Department of Laboratory Medicine, First Hospital of Shanxi Medical University, Taiyuan 030001, China.
Department of Respiratory and Critical Medicine, First Hospital of Shanxi Medical University, Taiyuan 030001, China.
Biomed Res Int. 2020 Nov 26;2020:7570981. doi: 10.1155/2020/7570981. eCollection 2020.
To investigate the immune status of people who previously had COVID-19 infections, we recruited two-week postrecovery patients and analyzed circulating cytokine and lymphocyte subsets. We measured levels of total lymphocytes, CD3 T cells, CD4 T cells, CD8 T cells, CD19 B cells, and CD56 NK cells and the serum concentrations of interleukin- (IL-) 1, IL-4, IL-6, IL-8, IL-10, transforming growth factor beta (TGF-), tumor necrosis factor alpha (TNF-), and interferon gamma (IFN-) by flow cytometry. We found that in most postrecovery patients, levels of total lymphocytes (66.67%), CD3 T cells (54.55%), CD4 T cells (54.55%), CD8 T cells (81.82%), CD19 B cells (69.70%), and CD56 NK cells (51.52%) remained lower than normal, whereas most patients showed normal levels of IL-2 (100%), IL-4 (80.88%), IL-6 (79.41%), IL-10 (98.53%), TNF- (89.71%), IFN- (100%), and IL-17 (97.06%). Compared to healthy controls, two-week postrecovery patients had significantly lower absolute numbers of total lymphocytes, CD3 T cells, CD4 T cells, CD8 T cells, CD19 B cells, and CD56 NK cells, along with significantly higher levels of IL-2, IL-4, IL-6, IL-10, TNF-, IFN-, and IL-17. Among postrecovery patients, T cells, particularly CD4 T cells, were positively correlated with CD19 B cell counts. Additionally, CD8 T cells were positively correlated with CD4 T cells and IL-2 levels, and IL-6 positively correlated with TNF- and IFN-. These correlations were not observed in healthy controls. By ROC curve analysis, postrecovery decreases in lymphocyte subsets and increases in cytokines were identified as independent predictors of rehabilitation efficacy. These findings indicate that the immune system gradually recovers following COVID-19 infection; however, the sustained hyperinflammatory response for more than 14 days suggests a need to continue medical observation following discharge from the hospital. Longitudinal studies of a larger cohort of recovered patients are needed to fully understand the consequences of the infection.
为了研究先前感染过 COVID-19 的人的免疫状况，我们招募了两周恢复期的患者，并分析了循环细胞因子和淋巴细胞亚群。我们通过流式细胞术测量了总淋巴细胞、CD3 T 细胞、CD4 T 细胞、CD8 T 细胞、CD19 B 细胞和 CD56 NK 细胞的水平，以及白细胞介素（IL）-1、IL-4、IL-6、IL-8、IL-10、转化生长因子-β（TGF-β）、肿瘤坏死因子-α（TNF-α）和干扰素-γ（IFN-γ）的血清浓度。我们发现，在大多数恢复期患者中，总淋巴细胞（66.67%）、CD3 T 细胞（54.55%）、CD4 T 细胞（54.55%）、CD8 T 细胞（81.82%）、CD19 B 细胞（69.70%）和 CD56 NK 细胞（51.52%）的水平仍低于正常水平，而大多数患者的 IL-2（100%）、IL-4（80.88%）、IL-6（79.41%）、IL-10（98.53%）、TNF-α（89.71%）、IFN-γ（100%）和 IL-17（97.06%）水平正常。与健康对照组相比，两周恢复期患者的总淋巴细胞、CD3 T 细胞、CD4 T 细胞、CD8 T 细胞、CD19 B 细胞和 CD56 NK 细胞的绝对数量明显较低，而 IL-2、IL-4、IL-6、IL-10、TNF-α、IFN-γ和 IL-17 的水平明显较高。在恢复期患者中，T 细胞，特别是 CD4 T 细胞，与 CD19 B 细胞计数呈正相关。此外，CD8 T 细胞与 CD4 T 细胞和 IL-2 水平呈正相关，IL-6 与 TNF-α和 IFN-γ呈正相关。这些相关性在健康对照组中未观察到。通过 ROC 曲线分析，发现淋巴细胞亚群减少和细胞因子增加是康复疗效的独立预测因素。这些发现表明，免疫系统在 COVID-19 感染后逐渐恢复；然而，超过 14 天的持续过度炎症反应表明出院后需要继续进行医学观察。需要对更大队列的康复患者进行纵向研究，以全面了解感染的后果。
