Question

please answer questions 4,5,6 only; if possible! thank you!

4. In patients with severe COVID-19, explain how having fewer of the cell type identified in question 3 could result in more severe symptoms of the disease. woolrollo enolhogona older 5. Briefly explain the function of the following proteins found in Table 2: a. C-reactive protein (CRP) b. Tumor necrosis factor-a (TNF-a) c. Interleukin 6 (IL-6) 6. Increased expression one of these three proteins (CRP, TNF-a, IL-6) may be responsible for the differences in cell types found between mild and severe patients. Which protein is it, and why?

Answer 1

Question 4

In patients with severe COVID 19 infection, it is seen that the neutrophils are more in number. But the lymphocytes are markedly reduced in numbers, hence there is a high neutrophil to lymphocyte ratio. Lymphocytes are the cells that cause viral clearance normally. Cytotoxic T cells destroy the virus infected cell, which is then phagocytosed. In severely infected cases, this process is not occurring. Also the collateral damage caused by neutrophils continue to occur.

Question 5

​​​​​​Functions of CRP

It is an acute phase reactant protein. It binds to the surface of microorganisms and act as a stimulator of classical pathway of complement. It also functions as opsonin for phagocytosis.

Question 6

IL 6 is elevated in those with severe disease. It causes exhaustion of cytotoxic T cells. It also prevents the development of regulatory T cells. It promotes release of other cytokines causing a cytokine storm. Added to this, the binding of virus to the ACE2 receptors inhibit interferon 3 activity, which normally destroys the virus.