• 1*Manar Mohammed Abd AL- Hassan, 2Izzat Abdulsatar Al-Rayahi, 3Hind Jaber Hassoon Author


The complement system plays a significant role in the human innate immune system during the COVID-19 pandemic exhibits several protective effects against the virus in order to eliminate cellular debris, induced inflammation. On the other hand, it plays a significant role in the pathogenesis of COVID-19, primarily through its involvement in multi-organ dysfunction and increasing the likelihood of adverse clinical outcomes. In order to confirm that the complement system contributes to COVID-19 pathogenicity, it is essential to measure the concentration of complement system proteins in COVID-19 patient sera compared to healthy individuals. This study aims to evaluate and quantify the level of C1q, C3, C4, and Properdin between the patients diagnosed with COVID-19 and control groups, specifically focusing on the statistically significant variations in patients' outcomes compared to the non-significant changes. This study measured classical pathway activation markers (C1q, C3, C4, and Properdin) in 70 Iraqi patients with COVID-19 as well as 20 healthy controls. Levels were assessed by the ELISA technique in Medical City hospitals in Baghdad between December 2022 and May 2023. Patients infected with SARS-COV-2 reported decreased levels of (C1q, C3, and C4) in their blood when compared with controls, as shown in Figure 1. In addition, C1q, C3, and C4 levels showed a notable disparity between their levels in the sera of patients in comparison to the healthy control (p=0.0164), (p=0.0282), (p=0.0454) respectively, with no statistically significant difference seen in Properdin levels between the study groups (p=0.8837). Based on the available evidence, this work represents the initial investigation of C1q, C3, C4, and Properdin in COVID-19 patients in Iraq. In conclusion, according to the complement level in serum, there was a highly significant disparity between patients with COVID-19 and the control group, except for Properdin level. It might be due to the classical pathway's hyperactivation and complement protein consumption during infection.




How to Cite

COMPLEMENT LEVEL CHANGES AMONG IRAQI COVID-19 PATIENTS. (2024). Romanian Journal of Diabetes, Nutrition and Metabolic Diseases, 31(1).