新型冠状病毒肺炎患者外周血T淋巴细胞亚群变化

doi:10.3877/cma.j.issn.1674-1358.2021.02.005

目的

探讨新型冠状病毒肺炎（COVID-19）患者外周血T淋巴细胞亚群水平及其临床意义。

方法

选择2020年1月至2020年3月中山大学附属第五医院感染科收治的93例COVID-19患者为研究组，随机选取2019年4月至2020年3月本院健康随访者92例为对照组，比较两组研究对象外周血白细胞、淋巴细胞、CD3⁺ T、CD4⁺ T和CD8⁺ T淋巴细胞水平。根据《新型冠状病毒肺炎诊疗方案（试行第七版）》中的临床分型标准，将COVID-19患者分为轻型、普通型、重型和危重型，分别比较各组患者入院时和入院治疗2周时外周血白细胞、淋巴细胞、CD3⁺ T、CD4⁺ T及CD8⁺ T淋巴细胞水平，采用Spearman相关系数检验分析以上各指标与疾病严重程度的相关性。

结果

COVID-19患者外周血中淋巴细胞（t = 3.94、P < 0.001）、CD3⁺ T（t = 3.33、P = 0.001）、CD4⁺ T（t = 3.73、P < 0.001）、CD8⁺ T（t = 2.18、P = 0.031）淋巴细胞计数显著低于对照组，差异具有统计学意义；COVID-19患者外周血中白细胞[（5.38 ± 2.97）× 10⁹/L]较对照组[（5.92 ± 1.16）× 10⁹/L]降低，但差异无统计学意义（t = 1.23、P = 0.222）。入院治疗2周时COVID-19患者白细胞计数较入院时显著升高（5.90 ± 1.96）× 10⁹/L vs. （5.38 ± 2.97）× 10⁹/L，差异有统计学意义（t = -3.47、P = 0.001），而淋巴细胞、T淋巴细胞亚群较入院时差异均无统计学意义（P均> 0.05）。入院时外周血白细胞、T淋巴细胞、CD3⁺ T、CD4⁺ T、CD8⁺ T细胞计数水平在不同严重程度患者间存在差异，且与疾病严重程度呈负相关（P均< 0.05）；治疗2周时不同临床分型患者外周血T淋巴细胞、CD3⁺ T、CD8⁺ T细胞计数水平多组间差异有统计学意义，亦与疾病严重程度呈负相关（P均< 0.05）。

结论

COVID-19患者外周血T淋巴细胞亚群存在不同程度表达失衡，与疾病严重程度呈负相关。检测外周血T淋巴细胞亚群水平对COVID-19诊断及病情严重程度评估具有重要意义。

关键词: 新型冠状病毒肺炎, 淋巴细胞, T淋巴细胞亚群, 免疫功能

Objective

To investigate the expression of peripheral T lymphocyte subsets of patients with coronavirus disease 2019 (COVID-19).

Methods

Total of 93 patients with COVID-19 admitted to Infection Department of the Fifth Affiliated Hospital of Sun Yat-Sen University from January 2020 to March 2020 were selected as research group, while 92 healthy follow-up individuals from April 2019 to March 2020 were randomly selected as control group. The levels of peripheral blood white blood cell (WBC), lymphocytes, CD3+ T, CD4+ T and CD8+ T lymphocytes were compared between the two groups. According to the clinical classification criteria in "New Coronavirus Pneumonia Diagnosis and Treatment Plan (Trial Seventh Edition)" , patients with COVID-19 were divided into mild group, ordinary group, severe group and critical group. WBC, lymphocytes, CD3+ T, CD4+ T and CD8+ T lymphocytes were compared between each group at admission and at two weeks after admission, and the correlation between above the indexes and severity of the disease was analyzed by Spearman correlation coefficient, respectively.

Results

Lymphocytes (t = 3.94, P < 0.001), CD3+ T (t = 3.33, P = 0.001), CD4+ T (t = 3.73, P < 0.001), CD8+ T (t = 2.18, P = 0.031) lymphocytes in COVID-19 patients were significantly lower than those in control group. Leukocytes of the patients with COVID-19 [(5.38 ± 2.97) × 109/L] was lower than that of control group [ (5.92 ± 1.16) × 109/L], but with no significant difference (t = 1.23, P = 0.222). Leukocytes of 93 patients with COVID-19 at two weeks after treatment were significantly higher than those at admission [(5.90 ± 1.96) × 109/L vs. (5.38 ± 2.97) × 109/L)], with significant difference (t =-3.47, P = 0.001), but there were no significant differences in lymphocytes and T lymphocyte subsets (all P > 0.05). The levels of leukocyte, T lymphocyte, CD3+ T, CD4+ T and CD8+ T lymphocytes at admission varied depending on the severity of the disease, and were negatively correlated with disease severity (all P < 0.05). The levels of T lymphocyte, CD3+ T and CD8+ T cell at two weeks of treatment were statistically different in patients with different clinical types, and were also negatively correlated with the severity of the disease (all P < 0.05).

Conclusions

There were imbalance expression of T lymphocyte subsets in patients with COVID-19, which were negatively correlated with the severity of the disease. The detection of peripheral T lymphocyte subsets was of great significance for the diagnosis and severity evaluation of COVID-19.

Key words: Coronavirus disease 2019, Lymphocytes, T lymphocyte subsets, Immune function

表1 一般资料

组别	例数	性别（例）		平均年龄（ ± s，岁）
组别	例数	男	女	平均年龄（ ± s，岁）
对照组	92	45	47	45.76 ± 11.34
感染组	93	40	53	47.73 ± 15.39
统计量		χ² = 3.756		t = 0.99
P值		0.053		0.322

表1 一般资料

组别	例数	性别（例）		平均年龄（ ± s，岁）
组别	例数	男	女	平均年龄（ ± s，岁）
对照组	92	45	47	45.76 ± 11.34
感染组	93	40	53	47.73 ± 15.39
统计量		χ² = 3.756		t = 0.99
P值		0.053		0.322

表2 COVID-19患者入院时外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

	例数	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
对照组	92	5.92 ± 1.16	2.07 ± 0.51	1 288 ± 339	739 ± 197	441 ± 152	1.80 ± 0.62
感染组	93	5.38 ± 2.97	1.64 ± 0.68	1 049 ± 464	573 ± 270	374 ± 179	1.69 ± 0.69
t值		1.23	3.94	3.33	3.73	2.18	0.94
P值		0.222	< 0.001	0.001	< 0.001	0.031	0.349

表2 COVID-19患者入院时外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

	例数	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
对照组	92	5.92 ± 1.16	2.07 ± 0.51	1 288 ± 339	739 ± 197	441 ± 152	1.80 ± 0.62
感染组	93	5.38 ± 2.97	1.64 ± 0.68	1 049 ± 464	573 ± 270	374 ± 179	1.69 ± 0.69
t值		1.23	3.94	3.33	3.73	2.18	0.94
P值		0.222	< 0.001	0.001	< 0.001	0.031	0.349

表3 入院时与入院治疗2周时COVID-19患者外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

检测时间	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
入院时	5.38 ± 2.97	1.64 ± 0.68	1 049 ± 464	573 ± 270	374 ± 179	1.69 ± 0.69
入院2周时	5.90 ± 1.96	1.65 ± 0.55	1 054 ± 359	590 ± 232	380 ± 156	1.71 ± 0.65
t值	-3.47	-0.22	0.98	0.84	0.40	0.65
P值	0.001	0.823	0.332	0.402	0.692	0.516

表3 入院时与入院治疗2周时COVID-19患者外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

检测时间	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
入院时	5.38 ± 2.97	1.64 ± 0.68	1 049 ± 464	573 ± 270	374 ± 179	1.69 ± 0.69
入院2周时	5.90 ± 1.96	1.65 ± 0.55	1 054 ± 359	590 ± 232	380 ± 156	1.71 ± 0.65
t值	-3.47	-0.22	0.98	0.84	0.40	0.65
P值	0.001	0.823	0.332	0.402	0.692	0.516

表4 不同临床分型患者入院时与入院2周时外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

组别		例数	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
轻型		5
	入院时		5.03 ± 1.47	1.89 ± 0.90	1 386 ± 235	723 ± 186	566 ± 76	1.29 ± 0.35
	入院2周时		6.43 ± 1.14	2.00 ± 0.44	1 149 ± 203	610 ± 160	476 ± 79	1.30 ± 0.36
	t值		-2.60	-0.48	3.66	5.30	1.94	-0.12
	P值		0.060	0.653	0.035	0.013	0.148	0.910
普通型		65
	入院时		5.24 ± 1.84	1.75 ± 0.69	1 134 ± 436	617 ± 258	400 ± 169	1.69 ± 0.70
	入院2周时		5.73 ± 1.96	1.74 ± 0.56	1 109 ± 342	611 ± 240	399 ± 139	1.63 ± 0.63
	t值		-2.00	0.12	1.42	1.34	0.89	0.33
	P值		0.050	0.903	0.164	0.187	0.380	0.740
重型		18
	入院时		4.72 ± 1.43	1.34 ± 0.37	854 ± 387	486 ± 245	302 ± 145	1.75 ± 0.65
	入院2周时		6.01 ± 1.84	1.40 ± 0.35	977 ± 351	579 ± 203	343 ± 184	1.92 ± 0.62
	t值		-2.34	-0.61	-1.15	-1.02	-1.37	0.25
	P值		0.032	0.552	0.279	0.336	0.205	0.807
危重型		5
	入院时		9.98 ± 10.39	1.08 ± 0.67	254 ± 120	147 ± 73	89 ± 58	1.85 ± 0.97
	入院2周时		7.28 ± 2.86	0.97 ± 0.34	417 ± 126	279 ± 104	112 ± 19	2.50 ± 0.78
	t值		0.58	0.60	-2.11	-1.76	-3.63	-0.51
	P值		0.594	0.584	0.170	0.221	0.068	0.663
F₁值			4.95	3.37	7.66	5.56	7.67	0.55
P₁值			0.003	0.022	< 0.001	0.002	< 0.001	0.648
F₂值			1.14	5.78	4.41	2.04	4.56	3.04
P₂值			0.339	0.001	0.007	0.117	0.006	0.035

表4 不同临床分型患者入院时与入院2周时外周血白细胞、淋巴细胞和T淋巴细胞亚群水平（ ± s）

组别		例数	白细胞（× 10⁹/L）	淋巴细胞（× 10⁹/L）	CD3⁺ T细胞（个/μl）	CD4⁺ T细胞（个/μl）	CD8⁺ T细胞（个/μl）	CD4⁺/CD8⁺ T
轻型		5
	入院时		5.03 ± 1.47	1.89 ± 0.90	1 386 ± 235	723 ± 186	566 ± 76	1.29 ± 0.35
	入院2周时		6.43 ± 1.14	2.00 ± 0.44	1 149 ± 203	610 ± 160	476 ± 79	1.30 ± 0.36
	t值		-2.60	-0.48	3.66	5.30	1.94	-0.12
	P值		0.060	0.653	0.035	0.013	0.148	0.910
普通型		65
	入院时		5.24 ± 1.84	1.75 ± 0.69	1 134 ± 436	617 ± 258	400 ± 169	1.69 ± 0.70
	入院2周时		5.73 ± 1.96	1.74 ± 0.56	1 109 ± 342	611 ± 240	399 ± 139	1.63 ± 0.63
	t值		-2.00	0.12	1.42	1.34	0.89	0.33
	P值		0.050	0.903	0.164	0.187	0.380	0.740
重型		18
	入院时		4.72 ± 1.43	1.34 ± 0.37	854 ± 387	486 ± 245	302 ± 145	1.75 ± 0.65
	入院2周时		6.01 ± 1.84	1.40 ± 0.35	977 ± 351	579 ± 203	343 ± 184	1.92 ± 0.62
	t值		-2.34	-0.61	-1.15	-1.02	-1.37	0.25
	P值		0.032	0.552	0.279	0.336	0.205	0.807
危重型		5
	入院时		9.98 ± 10.39	1.08 ± 0.67	254 ± 120	147 ± 73	89 ± 58	1.85 ± 0.97
	入院2周时		7.28 ± 2.86	0.97 ± 0.34	417 ± 126	279 ± 104	112 ± 19	2.50 ± 0.78
	t值		0.58	0.60	-2.11	-1.76	-3.63	-0.51
	P值		0.594	0.584	0.170	0.221	0.068	0.663
F₁值			4.95	3.37	7.66	5.56	7.67	0.55
P₁值			0.003	0.022	< 0.001	0.002	< 0.001	0.648
F₂值			1.14	5.78	4.41	2.04	4.56	3.04
P₂值			0.339	0.001	0.007	0.117	0.006	0.035

表5 COVID-19患者临床分型与白细胞和外周血T淋巴细胞亚群水平的相关性

时间		轻型、普通型、重型、危重型
时间		白细胞	淋巴细胞	CD3⁺ T细胞	CD4⁺ T细胞	CD8⁺ T细胞	CD4⁺/CD8⁺ T
入院时
	r值	-0.013	-0.305	-0.449	-0.393	-0.460	0.152
	P值	0.900	0.003	< 0.001	< 0.001	< 0.001	0.190
入院2周时
	r值	0.065	-0.401	-0.260	-0.169	-0.366	0.360
	P值	0.534	< 0.001	0.032	0.169	0.002	0.003

表5 COVID-19患者临床分型与白细胞和外周血T淋巴细胞亚群水平的相关性

时间		轻型、普通型、重型、危重型
时间		白细胞	淋巴细胞	CD3⁺ T细胞	CD4⁺ T细胞	CD8⁺ T细胞	CD4⁺/CD8⁺ T
入院时
	r值	-0.013	-0.305	-0.449	-0.393	-0.460	0.152
	P值	0.900	0.003	< 0.001	< 0.001	< 0.001	0.190
入院2周时
	r值	0.065	-0.401	-0.260	-0.169	-0.366	0.360
	P值	0.534	< 0.001	0.032	0.169	0.002	0.003

图1 COVID-19患者临床分型与白细胞和外周血T淋巴细胞亚群水平的相关性

[1]	Jiang S, Xia S, Ying T, et al. A novel coronavirus (2019-nCoV) causing pneumonia-associated respiratory syndrome[J]. Cell Mol Immunol,2020,17(5):554-554.
[2]	Wang W, Tang J, Wei F. Updated understanding of the outbreak of 2019 novel coronavirus (2019-nCoV) in Wuhan, China[J]. J Med Virol,2020,92(4):441-447
[3]	World Health Organization. Coronavirus disease 2019 (COVID-19) situation report-62[EB/OL]. 2020-03-22. URL
[4]	Xu X, Chen P, Wang J, et al. Evolution of the novel coronavirus from the ongoing Wuhan outbreak and modeling of its spike protein for risk of human transmission[J]. Sci China Life Sci,2020,63(3):457-460.
[5]	Zhou P, Yang X, Wang X, et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin[J]. Nature,2020,579(7798):270- 273.
[6]	Li T, Qiu Z, Zhang L, et al. Significant changes of peripheral T lymphocyte subsets in patients with severe acute respiratory syndrome[J]. J Infect Dis,2004,189(4):648-651.
[7]	Wong R, Wu A, To K, et al. Haematological manifestations in patients with severe acute respiratory syndrome: retrospective analysis[J]. BMJ,2003,326(7403):1358-1362.
[8]	He Z, Zhao C, Dong Q, et al. Effects of severe acute respiratory syndrome (SARS) coronavirus infection on peripheral blood lymphocytes and their subsets[J]. Int J Infect Dis,2005,9(6):323-330.
[9]	Li T, Xie J, He Y, et al. Long-term persistence of robust antibody and cytotoxic T cell responses in recovered patients infected with SARS coronavirus[J]. PLoS One,2006,1(1):e24.
[10]	国家卫生健康委办公厅. 新型冠状病毒肺炎诊疗方案(试行第七版)[J]. 传染病信息,2020,33(1):1-6.
[11]	Avitan T, Drukker L, Pri-Chen H, et al. Fetal urine production rate in preterm premature rupture of membranes is associated with adverse neonatal outcome: A pilot study[J]. Gynecol Obstet Invest,2018,83(1):57-64.
[12]	Diao B, Wang C, Tan Y, et al. Reduction and functional exhaustion of T cells in patients with coronavirus disease 2019 (COVID-19)[J]. Front Immunol,11:821-827.
[13]	Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China[J]. JAMA,2020,323(11):1061-1069.
[14]	Chen N, Zhou M, Dong X, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study[J]. Lancet,2020,395(10223):507-513. Chen G, Wu D, Guo W, et al., Clinical and immunologic features in severe and moderate Coronavirus Disease 2019[J]. J Clin Invest,2020,130(5):2620-2629.
[15]	Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China[J]. Lancet, 2020,395(10223):497-506.
[16]	Zhu N, Zhang D, Wang W, et al. A novel coronavirus from patients with pneumonia in China, 2019[J]. N Engl J Med,2020,382(8):727-733.
[17]	Li Q, Guan X, Wu P, et al. Early Transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia[J]. N Engl J Med,2020,382(13):1199-1207.
[18]	Organization World Health. Coronavirus disease (COVID-19) advice for the public: Myth busters [EB/OL]. [2020-04-05]. URL
[19]	Emami A, Javanmardi F, Pirbonyeh N, et al. Prevalence of underlying diseases in hospitalized patients with COVID-19: a systematic review and Meta-analysis[J]. Arch Acad Emerg Med,2020,8(1):e35.
[20]	李太生. T淋巴细胞亚群和病毒感染[J]. 中华内科杂志,2011,50(12):995-998.
[21]	Chan J, Yuan S, Kok K, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster[J]. Lancet, 2020,395(10223):514-523.
[22]	Rokni M, Ghasemi V, Tavakoli Z. Immune responses and pathogenesis of SARS-CoV-2 during an outbreak in Iran: Comparison with SARS and MERS[J]. Rev Med Virol,2020,30(3):e2107.
[23]	侯可可, 张娜, 李桃, 等. 新型冠状病毒肺炎不同时期CT表现及中性粒细胞/淋巴细胞比值, T淋巴细胞亚群变化[J]. 放射学实践,2020,35(3):272-276.
[24]	Jiang W, Zeng Z, Fan D, et al. Decreased counts of T lymphocyte subsets predict prognosis in SARS-CoV-2-infected pneumonia in Wuhan, China: A retrospective study[J]. Lancet Respir Med,2020. [Preprint].

[1]	徐保平, 彭怀文, 喻怀斌, 王晓涛. 新型冠状病毒肺炎继发糖尿病酮症酸中毒合并肝门静脉积气一例[J/OL]. 中华实验和临床感染病杂志(电子版), 2024, 18(04): 250-255.
[2]	丁丁, 杨云川, 马翔, 马中正, 霍俊一, 周磊. 术前C-反应蛋白-白蛋白-淋巴细胞比值在肝细胞癌预后中的价值评估[J/OL]. 中华普通外科学文献(电子版), 2024, 18(04): 261-265.
[3]	赖全友, 高远, 汪建林, 屈士斌, 魏丹, 彭伟. 三维重建技术结合腹腔镜精准肝切除术对肝癌患者术后CD4+、CD8+及免疫球蛋白水平的影响[J/OL]. 中华普外科手术学杂志(电子版), 2024, 18(06): 651-654.
[4]	刘春军, 严方方, 王宝锋, 常婷婷, 郭红红, 李志强. 替加环素联合人免疫球蛋白治疗XDRAB致VAP 的疗效分析[J/OL]. 中华肺部疾病杂志(电子版), 2024, 17(05): 797-800.
[5]	董学峰, 常乐, 蔡振煜. 血清ESR、CRP及PLR、MLR联合诊断结缔组织相关性间质性肺炎的意义[J/OL]. 中华肺部疾病杂志(电子版), 2024, 17(03): 430-433.
[6]	尹炳驿, 张楚楚, 刘艺, 林洪生. 益气清金汤加味治疗晚期非小细胞肺癌的临床分析[J/OL]. 中华肺部疾病杂志(电子版), 2024, 17(03): 462-465.
[7]	刘敏思, 李荣, 李媚. 基于GGT与Plt比值的模型在HBV相关肝细胞癌诊断中的作用[J/OL]. 中华肝脏外科手术学电子杂志, 2024, 13(06): 831-835.
[8]	伍细蓉, 徐立文, 陈亚琼. 基于LPR和FARI构建肝衰竭患者生存预后模型[J/OL]. 中华肝脏外科手术学电子杂志, 2024, 13(05): 675-681.
[9]	何慧玲, 鲁祖斌, 冯嘉莉, 梁声强. 术前外周血NLR和PLR对结肠癌术后肝转移的影响[J/OL]. 中华肝脏外科手术学电子杂志, 2024, 13(05): 682-687.
[10]	施麟宵, 洪兰兰, 阳柳, 芶碧珍, 刘畅, 吴欣. 钠-葡萄糖协同转运蛋白2 抑制剂治疗原发性膜性肾病的疗效及其对Th1/Th2 的影响[J/OL]. 中华肾病研究电子杂志, 2024, 13(05): 261-267.
[11]	崔健, 夏青, 林云, 李光玲, 李心娜, 王位. 血小板与淋巴细胞比值、免疫球蛋白、心肌酶谱及心电图对中老年肝硬化患者病情及预后的影响[J/OL]. 中华消化病与影像杂志(电子版), 2024, 14(05): 400-406.
[12]	崔秋子, 姚红曼, 艾迎春. 监测NLR、PLR、CAR、白蛋白、血钙及血糖指标水平对急性胰腺炎患者急性肾损伤的预测价值分析[J/OL]. 中华消化病与影像杂志(电子版), 2024, 14(03): 244-248.
[13]	高静, 夏婷婷. 血清乳酸脱氢酶、中性粒细胞/淋巴细胞比值、血浆纤维蛋白原/前白蛋白比值对晚期结直肠癌患者姑息化疗效果与不良反应的评价[J/OL]. 中华消化病与影像杂志(电子版), 2024, 14(03): 203-207.
[14]	江小珍, 陈秀贤, 陈宗威. 培门冬酶化疗后发生极重度高三酰甘油的分析和治疗[J/OL]. 中华临床实验室管理电子杂志, 2024, 12(03): 184-186.
[15]	席静妮, 李娜, 张琪. 中性粒细胞与淋巴细胞比值对老年重症社区获得性肺炎进展为脓毒症的预测价值[J/OL]. 中华老年病研究电子杂志, 2024, 11(03): 28-31.

阅读次数

全文

摘要

选择文件类型/文献管理软件名称

选择包含的内容

T lymphocyte subsets in peripheral blood of patients with coronavirus disease 2019

模态框（Modal）标题

选择文件类型/文献管理软件名称

选择包含的内容

T lymphocyte subsets in peripheral blood of patients with coronavirus disease 2019