Question

Which of the following is true regarding DAF and MCP?

a. Inactivate C3b on a pathogen surface
b. Stabilizes C3 convertase on a pathogen surface
c. Disrupts the C3 convertase on a human cell surface by cleaving it making it inactive
d. Is not involved in complement

Answer 1

The correct option is c. DAF cleaves and inactivates the C3 convertase on the surface of a human cell, while MCP stabilizes the C3 convertase on the surface of a pathogen.

Step-by-step explanation:

DAF (Decay Accelerating Factor) and MCP (Membrane Cofactor Protein) are two proteins involved in the complement system, which is a part of the immune response. The complement system helps to identify and eliminate pathogens from the body.

Option C is true regarding DAF and MCP. DAF cleaves and inactivates the C3 convertase enzyme on the surface of a human cell, preventing excessive complement activation and damage to host cells. MCP stabilizes the C3 convertase on the surface of a pathogen, promoting the efficient activation of the complement system against the pathogen.