RUDN University Doctors: Macrophages Can Help Treat Patients with Severe COVID-19
RUDN University doctors summarized and analysed research data on the role of macrophages in COVID-19. Scientists have concluded that monitoring the activity of macrophages can become a method of treating patients who have developed acute respiratory distress syndrome in COVID-19. The results are published in Frontiers in Immunology.
One of the complications of SARS-CoV-2 infection is the acute respiratory distress syndrome (ARDS). With ARDS, there is shortness of breath, dry cough, chest pain, bluish skin color and other symptoms. ARDS together with blood clotting disorders, edema and pneumonia, is the effect of massive activation of macrophages—immune cells that destroy foreign particles. RUDN doctors summarised data from about 200 studies to determine the role of macrophages in the development of COVID-19 complicated by ARDS.
"Activation of immune cells provides elimination of the viruses but its excessive infiltration and functioning can lead to tissues injury. Lung autopsies of patients who died of COVID-19 reveal extensive cellular infiltration with the predominance of macrophages. We focused on the role of macrophages in COVID-19, as pathogenesis of the new coronavirus infection, especially in cases complicated by ARDS. Identification of cellular and molecular mechanisms related to the role of macrophages in ARDS is highly relevant for the development of potential treatment strategies for COVID-19", said Anna Kosyerva, Ph.D., associate professor of the Department of Histology, Cytology and Embryology of the RUDN University.
Doctors have studied about 200 papers on this topic. The scientists analysed the role of two types of lung macrophages separately. The first is macrophages that emerged from monocytes and entered the lungs with the blood. Additionally, doctors evaluated the role of monocytes themselves. The second group of macrophages includes alveolar macrophages, which are constantly located in the lungs, and do not "travel" with blood through the body.
RUDN University researchers concluded that the severity of the disease depends by the ratio of alveolar and monocyte-derived macrophages. The second important factor is what function macrophages perform at the moment: pro-inflammatory or anti-inflammatory. Doctors called the control of this balance a possible direction for COVID-19 therapy. For example, in the early stages of ARDS, lung macrophages take on a pro-inflammatory role. Therefore, to reduce the severity of inflammation at this stage, it is necessary to reprogram macrophages genetically or chemically for anti-inflammatory function. The next stage is the opposite—the involved macrophages switch from pro-inflammatory to anti-inflammatory. The final phase of the ARDS will depend on the delicate balance of these two functions. It will also determine the severity of the ARDS. There are potential ways to control the functioning of macrophages but they are not in the wide clinical practice.
"The use of cell therapy with reprogrammed macrophages for the treatment of ARDS may be successful in COVID-19. Switching macrophage polarization from pro-inflammatory to anti-inflammatory phenotype in the early phase of ARDS can alleviate the enormous production of pro-inflammatory cytokines thereby preventing a cytokine storm and reducing mortality in patients with coronavirus infections. Efficient techniques of macrophage modification (safe and otherwise suitable for clinical purposes) are under way", said Anna Kosyerva, Ph.D., associate professor of the Department of Histology, Cytology and Embryology of the RUDN University.
More information:
Anna Kosyreva et al, The Role of Macrophages in the Pathogenesis of SARS-CoV-2-Associated Acute Respiratory Distress Syndrome, Frontiers in Immunology (2021). DOI: 10.3389/fimmu.2021.682871
Provided by RUDN University
