Santinelli Letizia, Lazzaro Alessandro, Sciarra Francesca, Maddaloni Luca, Frasca Federica, Fracella Matteo, Moretti Sonia, Borsetti Alessandra, Bugani Ginevra, Alessandri Francesco, Zullino Veronica, Ruberto Franco, Pugliese Francesco, Sorrentino Leonardo, Gianfrilli Daniele, Isidori Andrea, Venneri Mary Anna, Mastroianni Claudio M, Ceccarelli Giancarlo, d'Ettorre Gabriella
Department of Public Health and Infectious Diseases, Sapienza University of Rome, 00185 Rome, Italy.
Department of Experimental Medicine, Sapienza University of Rome, 00185 Rome, Italy.
Pathogens. 2023 Mar 11;12(3):442. doi: 10.3390/pathogens12030442.
SARS-CoV-2 related immunopathology may be the driving cause underlying severe COVID-19. Through an immunophenotyping analysis on paired bronchoalveolar lavage fluid (BALF) and blood samples collected from mechanically ventilated patients with COVID-19-associated Acute Respiratory Distress Syndrome (CARDS), this study aimed to evaluate the cellular immune responses in survivors and non-survivors of COVID-19.
A total of 36 paired clinical samples of bronchoalveolar lavage fluid (BALF) mononuclear cells (BALF-MC) and peripheral blood mononuclear cells (PBMC) were collected from 18 SARS-CoV-2-infected subjects admitted to the intensive care unit (ICU) of the Policlinico Umberto I, Sapienza University Hospital in Rome (Italy) for severe interstitial pneumonia. The frequencies of monocytes (total, classical, intermediate and non-classical) and Natural Killer (NK) cell subsets (total, CD56 and CD56), as well as CD4 and CD8 T cell subsets [naïve, central memory (TCM) and effector memory (TEM)], and those expressing CD38 and/or HLADR were evaluated by multiparametric flow cytometry.
Survivors with CARDS exhibited higher frequencies of classical monocytes in blood compared to non-survivors ( < 0.05), while no differences in the frequencies of the other monocytes, NK cell and T cell subsets were recorded between these two groups of patients ( > 0.05). The only exception was for peripheral naïve CD4 T cells levels that were reduced in non-survivors ( = 0.04). An increase in the levels of CD56 ( = 0.012) and a decrease in CD56 ( = 0.002) NK cell frequencies was also observed in BALF-MC samples compared to PBMC in deceased COVID-19 patients. Total CD4 and CD8 T cell levels in the lung compartment were lower compared to blood ( = 0.002 and < 0.01, respectively) among non-survivors. Moreover, CD38 and HLA-DR were differentially expressed by CD4 and CD8 T cell subsets in BALF-MC and in PBMC among SARS-CoV-2-infected patients who died from COVID-19 ( < 0.05).
These results show that the immune cellular profile in blood and pulmonary compartments was similar in survivors and non-survivors of COVID-19. T lymphocyte levels were reduced, but resulted highly immune-activated in the lung compartment of patients who faced a fatal outcome.
与严重急性呼吸综合征冠状病毒2（SARS-CoV-2）相关的免疫病理学可能是重症2019冠状病毒病（COVID-19）的潜在驱动因素。通过对从患有COVID-19相关急性呼吸窘迫综合征（CARDS）的机械通气患者采集的配对支气管肺泡灌洗液（BALF）和血液样本进行免疫表型分析，本研究旨在评估COVID-19幸存者和非幸存者的细胞免疫反应。
从意大利罗马萨皮恩扎大学医院翁贝托一世综合医院重症监护病房（ICU）收治的18例因严重间质性肺炎感染SARS-CoV-2的患者中，共采集了36对支气管肺泡灌洗液（BALF）单核细胞（BALF-MC）和外周血单核细胞（PBMC）的临床样本。通过多参数流式细胞术评估单核细胞（总数、经典型、中间型和非经典型）和自然杀伤（NK）细胞亚群（总数、CD56和CD56）的频率，以及CD4和CD8 T细胞亚群[初始型、中枢记忆（TCM）和效应记忆（TEM）]，以及表达CD38和/或人类白细胞抗原DR（HLADR）的细胞频率。
与非幸存者相比，患有CARDS的幸存者血液中经典单核细胞的频率更高（<0.05），而在这两组患者中，其他单核细胞、NK细胞和T细胞亚群的频率没有差异（>0.05）。唯一的例外是外周初始CD4 T细胞水平在非幸存者中降低（= 0.04）。与PBMC相比，在已故COVID-19患者的BALF-MC样本中还观察到CD56 NK细胞频率增加（= 0.012）和CD56 NK细胞频率降低（= 0.002）。在非幸存者中，肺组织中总的CD4和CD8 T细胞水平低于血液（分别为= 0.002和<0.01）。此外，在死于COVID-19的SARS-CoV-2感染患者中，BALF-MC和PBMC中的CD4和CD8 T细胞亚群对CD38和HLA-DR的表达存在差异（<0.05）。
这些结果表明，COVID-19幸存者和非幸存者血液和肺组织中的免疫细胞谱相似。T淋巴细胞水平降低，但在面临致命结局的患者的肺组织中高度免疫激活。
