Table 1.

Expressional markers used to determine cell populations and characteristics in flowcytometric analysis and single cell western blotting

Marker Name	Expression Profile	Reference
CD45	CD45 is expressed on all myeloid derived cells including interstitial and alveolar macrophages.	(32,33)
Siglec F	Siglec F is highly expressed on alveolar macrophages.	(32)
F4/80	F4/80 is expressed on lung macrophages including both alveolar and interstitial.	(32)
CD11b	CD11b is expressed in interstitial macrophages with lower expression in resident alveolar macrophages. Expression indicates a more migratory phenotype in alveolar macrophages but is characteristic of interstitial macrophages.	(34)
CD11c	CD11c is expressed on resident alveolar macrophages and is a marker of mature interstitial macrophages	(34,35)
MR (CD206)	MR is a profibrotic marker expressed on activated interstitial macrophages. It may also be expressed on alveolar macrophages, indicating M2 polarization.	(32,36)
Ly6C	Ly6C is a pro-inflammatory marker expressed on activated interstitial macrophages, eventually contributing to fibrosis. This marker may also be expressed on alveolar macrophages in a similar manner.	(37,38)
CD31	CD31 is an endothelial cell marker	(39)
SCA-1	SCA-1 is expressed on cells expressing stem cell like characteristics	(40)
CD44	CD44 is expressed on cells undergoing epithelial to mesenchymal transition leading to a pro-fibrotic phenotype	(41)
CD90	CD90 is a marker of proliferation that is expressed on mesenchymal stem cells	(42)
HMGB1	HMGB1 is a pro-inflammatory marker expressed on activated pulmonary macrophages, indicating active inflammation	(43)
ZEB-1	ZEB-1 is a pro-fibrotic marker involved in epithelial to mesenchymal transition and is indicative of fibrosis	(41)