Q8 of 70 Page 55

What are interferons? How do interferons check infection of new cells?

Interferons are a group of natural proteins released by the host cell in the presence of any virus, tumour cells and parasites etc. In classic cases the viral infected cell releases interferon which heightens the antiviral response of the nearby cells.

Interferons check infection of new cells as:


1. Interferons inhibit viral replication within the host cells.


2. Which in turn activates the natural killer cells and macrophages .


3. This increases the presentation of antigens to lymphocytes.


4. Now, these antigens multiply and remove the pathogen.


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