Huang Mingxiang, Wang Yao, Ye Jing, Da Hongqiang, Fang Sufang, Chen Lizhou
Fuzhou Pulmonary Hospital & Fujian Medical University Clinical Teaching Hospital, Fuzhou, China.
Ann Transl Med. 2020 Sep;8(18):1145. doi: 10.21037/atm-20-5479.
In December 2019, an outbreak of coronavirus disease 2019 (COVID-19), caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), occurred in Wuhan City, Hubei Province, China. The coronavirus has spread throughout the world, posing a severe threat to human health. By using flow cytometry, here we observed the dynamic changes of peripheral blood T lymphocyte subsets in COVID-19 patients, with an attempt to explore their roles in the pathogenesis of COVID-19 and their impacts on prognosis.
Eighty-nine COVID-19 patients were divided into a moderate group (n=70) and the severe/critical group (n=19) according to the disease severity. Furthermore, the severe/critical patients were divided into the improved group (n=14) and unimproved group (n=5) according to the outcomes. The absolute peripheral blood lymphocytes counts and subsets, including CD45+, CD3+, CD4+, and CD8+, in the acute phase, and flow cytometry measured the recovery phase for all patients. Then, the results were compared with those in the normal control group.
The absolute counts of lymphocytes, T lymphocytes, and their subsets decreased during the acute phase in COVID-19 patients, especially in the severe/critical group. The T-lymphocyte count reached the lowest point on the 14th day in the severe/critical group. It rose with fluctuations to the normal level in the improved group as the immune function recovered; in the unimproved group, however, the T-lymphocyte count remained at a low level or even continued to decrease. The percentages of CD4+ and CD8+ T lymphocytes showed no visible change in the improved group; however, the percentage of CD8+ T cells dropped in the unimproved group, resulting in higher CD4+/CD8+ ratio.
T lymphocytes count, and their subsets can be used for monitoring the immune functions and predicting the prognosis of COVID-19 patients.
2019年12月，中国湖北省武汉市爆发了由新型严重急性呼吸综合征冠状病毒2（SARS-CoV-2）引起的2019冠状病毒病（COVID-19）。该冠状病毒已在全球传播，对人类健康构成严重威胁。在此，我们通过流式细胞术观察了COVID-19患者外周血T淋巴细胞亚群的动态变化，试图探讨它们在COVID-19发病机制中的作用及其对预后的影响。
89例COVID-19患者根据疾病严重程度分为中度组（n=70）和重度/危重组（n=19）。此外，重度/危重症患者根据预后分为好转组（n=14）和未好转组（n=5）。对所有患者在急性期进行外周血淋巴细胞绝对计数及包括CD45+、CD3+、CD4+和CD8+在内的亚群分析，并在恢复期采用流式细胞术检测。然后，将结果与正常对照组进行比较。
COVID-19患者急性期淋巴细胞、T淋巴细胞及其亚群的绝对计数下降，尤其是在重度/危重组。重度/危重组T淋巴细胞计数在第14天达到最低点。随着免疫功能恢复，好转组T淋巴细胞计数波动上升至正常水平；然而，在未好转组，T淋巴细胞计数仍处于低水平甚至继续下降。好转组CD4+和CD8+T淋巴细胞百分比无明显变化；然而，未好转组CD8+T细胞百分比下降，导致CD4+/CD8+比值升高。
T淋巴细胞计数及其亚群可用于监测COVID-19患者的免疫功能并预测其预后。
