Question

How would a macrophage deficiency likely affect a person’s innate and adaptive defenses?

Short answer

A macrophage deficiency would affect a person’s innate and adaptive defenses by causing frequent infections and poor innate responses. Macrophages are attributed to protecting the host from infection and are key components of the innate immune system.

Step-by-step solution

Macrophages

Macrophages are antigen-presenting cells that actively phagocytose large particles. They possess receptors that attach to polysaccharides found on the surface of foreign cells and work as innate immune cells through phagocytosis.

Therefore, they are crucial in presenting antigens obtained from phagocytosed infectious organisms, including bacteria and parasites.

Helper T cells

A helper T cell refers to a type of lymphocyte that stimulates B cells to produce antibodies. It is the essential cells in adaptive immunity that play a significant role in the immune system.

Phagocytosis helps macrophages present antigens and promotes helper T cells, which interact with antigen fragments on the surface of antigen-presenting cells.

Innate and adaptive responses

Infections caused by macrophage deficiency result in poor innate responses because of diminished phagocytosis and reduced inflammation. The other cause will be poor adaptive responses because of the absence of macrophages to present antigens to helper T cells.