Question

A lot of attention has been dedicated to the so-called "cytokine storm" that can occur in patients with COVID-19. What are cytokines, and what is a cytokine storm? Why are they potentially life-threatening? What is one potential therapeutic that is being developed to combat the cytokine storm?

Answer 1

Ans- Cytokine is a generic term for any low molecular weight soluble protein or glycoprotein released by one cell population (macrophages) which acts as an intracellular mediator. It includes monokines , lymphokines, interleukins, interferons .

* Cytokine Storm : A severe immune reaction in which the body releases too many cytokines into the blood too quickly.  This production of these cytokines in uncontrolled or abrupt way is described as as a “cytokine storm ” .

* Cytokine storm results in vasolidation leading to low blood pressure ,  triggers a flood of white blood cells to enter infection site (the lungs , as in case of Covid 19) , battle between White blood cells and viral infected cells leads to accumulation of dead cells and fluid , subsequently resulting in organ failure.The hyperactivated macrophages leads to the destruction of the hematopoietic stem cells in the bone marrow, which leads to anemia. Heightened interleukin1b results in fever and organ failure. The excessive tumor necrosis factor causes massive death of the cells lining the blood vessels, leading to clotting thus hampering blood circulation.

* One strategy for the treatment of COVID is to  break  the vicious cycle of the “cytokine storm.” This can be done by using antibodies to block the primary mediators of the storm , like IL6, or its receptor, which is present on the cells of the body.

*  Tumor necrosis factor can be inhibited with the use of approved antibody drugs like Humira or Remicade, with a soluble receptor such as Enbrel which binds to tumor necrosis factor and prevents it from triggering inflammation.