MPS vs system of macrophages

MPS and system of macrophages both are nouns.

Word	Noun	Adjective	Verb	Adverb
MPS	Yes	No	No	No
system of macrophages	Yes	No	No	No

As nouns, MPS and system of macrophages are synonyms defined as:

MPS and system of macrophages: a widely distributed system of free and fixed macrophages derived from bone marrow

Other synonyms of MPS include mononuclear phagocyte system.

MPS (noun)	system of macrophages (noun)
a widely distributed system of free and fixed macrophages derived from bone marrow	a widely distributed system of free and fixed macrophages derived from bone marrow