The tissue macrophage is derived from :
A
Eosinophil
B
Helper T cell
C
Lymphocyte
D
Monocyte
Correct Answer: Monocyte
Macrophages that reside in adult healthy tissues either derive from circulating monocytes or are established before birth and then maintained during adult life independently of monocytes. By contrast, most of the macrophages that accumulate at diseased sites typically derive from circulating monocytes.