Keshavarz Fatemeh, Ghalamfarsa Farideh, Javdansirat Saeed, Hasanzadeh Sajad, Azizi Arsalan, Sabz Gholamabbas, Salehi Marziyeh, Ghalamfarsa Ghasem
Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran.
Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
Virusdisease. 2021 Dec;32(4):681-689. doi: 10.1007/s13337-021-00710-6. Epub 2021 Oct 2.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is a new virus that emerged in China and immediately spread around the world. Evidence has been documented that the immune system is impressively involved in the pathogenesis of this disease, especially in causing inflammation. One of the important components of the immune system is the complement system whose increased activity has been shown in inflammatory diseases and consequently damage caused by the activity of its components. In the present study, serum levels of C3 and C4 factors as well as the activity level of complement system in the classical pathway were measured by CH50 test in patients with SARS-CoV-2. Participants in the study consisted of 53 hospitalized patients whose real-time PCR test was positive for SARS-CoV-2. The mean age of these patients was 42.06 ± 18.7 years, including 40% women and 60% men. The most common symptoms in these patients were cough (70%), fever (59%), dyspnea (53%) and chills (53%), respectively. Analysis of biochemical and hematological test results revealed that 26 (49%) patients had lymphopenia, 34 (64%) patients were positive for C-reactive protein (CRP) and 26 (49%) patients had ESR and LDH levels significantly higher than normal. In addition, 27 patients (51%) had vitamin D deficiency. The mean CH50 activity level in COVID-19 patients was significantly reduced compared to healthy individuals (84.9 versus 169.9 U/ml, = < 0.0001). Comparison of the mean CH50 activity levels between different subgroups of patients indicated that COVID-19 patients with decreased peripheral blood lymphocyte count and positive CRP had a significant increase in activity compared to the other groups ( = 0.0002). The serum levels of C3 and C4 factors had no significant change between patients and healthy individuals. Conclusion: The activity level of complement system in the classical pathway decreases in COVID-19 patients compared to healthy individuals, due to increased activity of complement system factors in these patients.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）引发了2019冠状病毒病（COVID-19），它是一种在中国出现并迅速在全球传播的新型病毒。已有证据表明，免疫系统在这种疾病的发病机制中发挥着重要作用，尤其是在引发炎症方面。免疫系统的重要组成部分之一是补体系统，其活性增加已在炎症性疾病中得到证实，并因此导致其成分活性造成损害。在本研究中，通过CH50试验测量了SARS-CoV-2患者血清中C3和C4因子水平以及经典途径中补体系统的活性水平。该研究的参与者包括53名住院患者，他们的SARS-CoV-2实时PCR检测呈阳性。这些患者的平均年龄为42.06±18.7岁，其中女性占40%，男性占60%。这些患者最常见的症状分别是咳嗽（70%）、发热（59%）、呼吸困难（53%）和寒战（53%）。对生化和血液学检测结果的分析显示，26名（49%）患者出现淋巴细胞减少，34名（64%）患者C反应蛋白（CRP）呈阳性，26名（49%）患者的血沉（ESR）和乳酸脱氢酶（LDH）水平显著高于正常。此外，27名患者（51%）存在维生素D缺乏。与健康个体相比，COVID-19患者的平均CH50活性水平显著降低（84.9对169.9 U/ml，P<0.0001）。患者不同亚组之间平均CH50活性水平的比较表明，外周血淋巴细胞计数降低且CRP呈阳性的COVID-19患者与其他组相比活性显著增加（P=0.0002）。患者与健康个体之间C3和C4因子的血清水平无显著变化。结论：与健康个体相比，COVID-19患者经典途径中补体系统的活性水平降低，原因是这些患者补体系统因子的活性增加。
