Virology Research Center, National Research Institute of Tuberculosis and Lung diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Pediatric Infectious Disease Research Center, Pediatrics Center of Excellence, Children's Medical Center Hospital, Tehran University of Medical Sciences, Dr. Gharib Street, Keshavarz Boulevard, Tehran, Iran.
BMC Infect Dis. 2021 Jul 5;21(1):646. doi: 10.1186/s12879-021-06278-2.
Although there are a growing number of studies on evaluating lymphocyte subset counts as prognostic factors for COVID-19 disease severity, the lymphocyte subsets' analyses of both IgM and IgG responders and non-responders during the periods after onset of symptoms, have not been conducted yet. So, this study aimed to evaluate immune cell profiling of COVID-19 patients with and without antibody responses.
In this cross-sectional study, the levels of peripheral lymphocyte subsets were measured using flow cytometry in 53 patients with positive SARS-CoV-2 RT-PCR, for whom antibody testing of COVID-19 was performed.
The white blood cell, neutrophil, and lymphocyte counts consistently decreased in the IgM and IgG non-responder group, while the differences in the median value between the two study groups were found to be statistically significant only in terms of neutrophil counts (P = 0.024 for IgM response and p-value = 0.046 for IgG response, respectively). Moreover, the level of neutrophil-to-lymphocyte ratio was observed to be significantly lower in the IgM or IgG non-responder group compared to the IgM or IgG responder group (3.6 ± 3.1 vs. 6.3 ± 4.2; p-value = 0.021). The patients with IgM antibody response had a significantly lower CD20 lymphocytes (11% versus 15% in the groups without IgM antibody response, p-value = 0.031), The percentages of NK cells and CD4 T cells significantly increased in the patients with IgG antibody response compared to those without IgG antibody response (13% versus 10%, p-value = 0.028, and 41.5% versus 34%; p-value = 0.03, respectively). Moreover, the patients who produced IgM or IgG antibody had significantly higher percentages of total T lymphocytes (64% versus 54%; p-value = 0.017), CD4 T cells (41% versus 34%; p-value = 0.038), and NK cells (13% versus 9%, p-value = 0.023) compared to the group with no serological response. No significant difference was observed in the percentage of other lymphocyte subsets, including CD8 T cells, T cells, and CD19 B cells.
Our results suggest that the total T cells, CD4 T cells, and NK cells percentages are linked to serological response. Moreover, our findings suggested that neutrophil absolute counts and neutrophil-to-lymphocyte ratio may be valuable predictors of IgM or IgG antibody response.
虽然有越来越多的研究评估淋巴细胞亚群计数作为 COVID-19 疾病严重程度的预后因素，但尚未对症状出现后 IgM 和 IgG 应答者和无应答者的淋巴细胞亚群进行分析。因此，本研究旨在评估有和无抗体应答的 COVID-19 患者的免疫细胞特征。
在这项横断面研究中，对 53 例 SARS-CoV-2 RT-PCR 阳性患者进行了外周血淋巴细胞亚群的流式细胞术检测，对这些患者进行了 COVID-19 抗体检测。
IgM 和 IgG 无应答组的白细胞、中性粒细胞和淋巴细胞计数持续下降，而两组间中位数的差异仅在中性粒细胞计数方面具有统计学意义（IgM 应答时为 P=0.024，IgG 应答时为 p 值=0.046）。此外，与 IgM 或 IgG 应答组相比，IgM 或 IgG 无应答组的中性粒细胞与淋巴细胞比值显著降低（3.6±3.1 比 6.3±4.2；p 值=0.021）。有 IgM 抗体应答的患者的 CD20 淋巴细胞明显较低（有 IgM 抗体应答组为 11%，无 IgM 抗体应答组为 15%，p 值=0.031），有 IgG 抗体应答的患者的 NK 细胞和 CD4 T 细胞百分比明显高于无 IgG 抗体应答的患者（13%比 10%，p 值=0.028 和 41.5%比 34%；p 值分别为 0.03 和 0.03）。此外，产生 IgM 或 IgG 抗体的患者的总 T 淋巴细胞（64%比 54%；p 值=0.017）、CD4 T 细胞（41%比 34%；p 值=0.038）和 NK 细胞（13%比 9%；p 值=0.023）的百分比明显高于无血清学反应的患者。其他淋巴细胞亚群（包括 CD8 T 细胞、T 细胞和 CD19 B 细胞）的百分比无显著差异。
我们的结果表明，总 T 细胞、CD4 T 细胞和 NK 细胞百分比与血清学反应有关。此外，我们的研究结果表明，中性粒细胞绝对值和中性粒细胞与淋巴细胞比值可能是 IgM 或 IgG 抗体反应的有价值预测指标。
