Front Neurol . Young COVID-19 Patients Show a Higher Degree of Microglial Activation When Compared to Controls

[tetano]

Front Neurol


. 2022 Jun 16;13:908081.
doi: 10.3389/fneur.2022.908081. eCollection 2022.
Young COVID-19 Patients Show a Higher Degree of Microglial Activation When Compared to Controls


Jakob Matschke ¹ , Henri Lahann ¹ , Susanne Krasemann ¹ , Hermann Altmeppen ¹ , Susanne Pfefferle ² , Giovanna Galliciotti ¹ , Antonia Fitzek ³ , Jan-Peter Sperhake ³ , Benjamin Ondruschka ³ , Miriam Busch ⁴ , Natalie Rotermund ⁴ , Kristina Schulz ⁴ , Christian Lohr ⁴ , Matthias Dottermusch ¹ , Markus Glatzel ¹



Affiliations

• PMID: 35785352
• PMCID: PMC9243237
• DOI: 10.3389/fneur.2022.908081

Abstract

The severe acute respiratory syndrome-corona virus type 2 (SARS-CoV-2) is the cause of human coronavirus disease 2019 (COVID-19). Since its identification in late 2019 SARS-CoV-2 has spread rapidly around the world creating a global pandemic. Although considered mainly a respiratory disease, COVID-19 also encompasses a variety of neuropsychiatric symptoms. How infection with SARS-CoV-2 leads to brain damage has remained largely elusive so far. In particular, it has remained unclear, whether signs of immune cell and / or innate immune and reactive astrogliosis are due to direct effects of the virus or may be an expression of a non-specific reaction of the brain to a severe life-threatening disease with a considerable proportion of patients requiring intensive care and invasive ventilation activation. Therefore, we designed a case-control-study of ten patients who died of COVID-19 and ten age-matched non-COVID-19-controls to quantitatively assess microglial and astroglial response. To minimize possible effects of severe systemic inflammation and / or invasive therapeutic measures we included only patients without any clinical or pathomorphological indication of sepsis and who had not been subjected to invasive intensive care treatment. Our results show a significantly higher degree of microglia activation in younger COVID-19 patients, while the difference was less and not significant for older COVID-19 patients. The difference in the degree of reactive gliosis increased with age but was not influenced by COVID-19. These preliminary data warrants further investigation of larger patient cohorts using additional immunohistochemical markers for different microglial phenotypes.

Keywords: COVID-19; SARS-CoV-2; astrocytes; microglia; nervous system; neuroinflammation; neuropathology.