MARKERS OF TISSUE DAMAGE AFTER SARS-CoV-2-INFECTION:serum Chemokines

SARS-CoV-2 infection of the upper respiratory tract continues to cause hundreds of deaths every day worldwide.Most of the efforts, however, continues to concentrate on avoiding transmission of the virus and on vaccination to prevent infection transmission.Both measures seem not to be enough. What is the clinical consequence of the entry of the virus into the nose? Flu-like symptoms and fever of different lenght at first.In the second phase respiratory distress can develop,which is the most important reason to seek help in the emergency room of an hospital even when the virus titer in the nose has already started to decrease. Laboratory changes such as moderate elevation of serum level of inflammation markers,like C-reactive protein,interleukin-6 and interleukin-8 but not of the classical sign of bacterial infections,increase of granulocyte number, are the characteristics of this viral infection. The main acute-phase mediator Interleukin-6 , responsible for the increase of serum level of the chemokine interleukin-8, mainly produced by the main liver cell,the largest cell of the body the hepatocyte, are considered to be „pro-inflammatory“ mediators.This definition is not appropriate and suggests that therapeutic interventions with the aim to inhibt their production,such as corticosteroids administration should be helpful to cure the acute viral infection.However the opposite is true. Interleukin-6,massively produced at the site of tissue damage,and reaching the liver trough the blood circulation, is one of the main component of the defence apparatus of the body aiming to eliminate the cause of tissue damage and to initiate the repair process by inducing a massive change of protein synthesis in the liver („acute-phase modus“).These proteins are called „positive acute-phase proteins“.Beside coagulation- ,complement- proteins and anti proteases, chemokines like interleukin-8 belong to the different groups of those proteins each with a special task,locally at the site of tissue damage and systemically (e.g.production of granulocytes in the bone marrow) within the defence system.In some cases an acute phase situation can take place within the liver itself when the clearance capacity of the hepatic tissue macrophages is overwhelmed and massive cytokine and chemokine-production is started in the liver.Also in these cases is inhibition of this production not the appropriate therapeutic measure to clear the cause of tissue damage which can even simply be dehydration and hypoxia after the virus being already eliminated.As corticosteroid therapy is sometimes initiated at an early time after infection,suppression of release of acute-phase cytokines by macrophages, may even cause a delay of viral clearance.The same holds true for the attempts to reduce the effect of interleukin-6 by administration of specific antibodies. https://lnkd.in/eGa2SpBe Interleukin-6-Production Is Responsible for Induction of Hepatic Synthesis of Several Chemokines as Acute-Phase Mediators in Two Animal Models: Possible Significance for Interpretation of Laboratory Changes in Severely Ill Patients

Interleukin-6-Production Is Responsible for Induction of Hepatic Synthesis of…

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