Question

Hyper-IgM syndrome is a rare genetic disease caused by a loss-of-function mutation in the gene that codes for the CD40L protein. What are the two most likely direct effects of CD40L deficiency?

Increased recruitment of neutrophils into inflamed tissue.

Reduced recruitment of neutrophils into inflamed tissue.

Reduced phagocytic function of macrophages.

A failure of the germinal center reaction.

A loss of IFN-γ function.

Answer 1

Reduced phagocytic function of macrophages

A loss of IFN-y function

CD40L deficiency tends to cause Hyper IgM syndrome and is due to loss of function in the gene encoding the CD40L protein. During this syndrome, the immune syndrome does not function properly due to irregularity in the maturation of the immune process and cells. Due to the deficiency in the CD40L proteins, it tends to reduce the activity of macrophage as they are not able to get right signal from the CD40L. Also, due to the deficiency in the CD40L, it is not able to activate the IFN-y as the CD40L stimulation is required for the production of the IFN-y