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.

中文翻译：

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持续跟踪COVID-19患者的免疫状况

背景

COVID-19威胁着全世界的人类健康。我们旨在调查具有临床进展的COVID-19患者的免疫状态的动态变化。

方法

从我们的研究中招募了61例COVID-19患者（42例轻度病例和19例严重病例，51例非继发感染为非感染组，10例继发细菌/真菌感染为感染组）和52例健康对照（HCs）医院。全自动血细胞分析仪和流式细胞仪分别检测白细胞分类，淋巴细胞亚群和细胞因子。

结果

入院后，与HCs相比，COVID-19患者的嗜酸性粒细胞和淋巴细胞亚群显着减少，而嗜中性粒细胞，单核细胞，嗜碱性粒细胞，IL-2，IL-6，IL-10和IFN-γ显着增加。CD3 ⁺ T和DN（CD3 ⁺ CD4 ^- CD8 ^- ）细胞出现持续下降，白细胞，嗜中性粒细胞，并与轻度组IL-10显示出严重的组中的持续增加。与非感染组相比，感染组中嗜酸性粒细胞，CD3 ⁺ T和CD4 ⁺ T细胞减少，但白细胞，嗜中性粒细胞，IL-6和IL-10却相反。此外，在严重的COVID-19患者组中，DN细胞与IL-10和DP（CD3 ⁺CD4 ⁺ CD8 ⁺细胞与IL-6呈负相关。淋巴细胞，嗜酸性粒细胞，CD3 ⁺ T细胞，CD4 ⁺ T细胞，IL-6和IL-10对COVID-19都有很好的诊断功效（AUC，0.905-0.975）。病情好转的COVID-19患者的实验室指标也显示随着时间的恢复趋势。

结论

COVID-19患者的免疫状态在每个阶段都不同，并且动态监测相关指标可以帮助预测疾病，并且可以避免细胞因子风暴。