Biodistribution, migration and homing of systemically applied mesenchymal stem/stromal cells

Table 1 Common themes in MSC biodistribution research

Theme	Targeted tissues (possible mechanism)	References
Increased homing after intra-arterial delivery compared with intravenous delivery?	Kidney	[33, 34]
	Joints	[32]
	Stroke	[30]
	Other (many) tissues	[31]
Side effects of intra-arterial versus intravenous delivery?	Incorporation into vessel wall	[23, 35]
	Obstruction of microvessels	[38]
	Vascular occlusion	[39]
Targeting of vessel wall and vessel-associated tissues?	Lungs, lymph nodes, intestine	[47]
Targeting of tissues for regeneration	Myocardium	[18, 48–55]
	Beta1 integrins	[48, 49]
	CCL2, monocytes	[52]
	Kidney	[33, 56–63]
	Gut and liver	[64–67]
	Skin	[44, 68–71]
	CCL21	[44]
	JAM-A	[68]
	Brain	[72–75]
	P/E selectin (CD44)	[73]
	CXCR4/flk-1/EPO-R	[74]
Homing to bone marrow	Bone marrow	[76–81]
	HCELL/E-selectin	[15]
	Subendothelial localization	[79]
Biodistribution to the immune system?	Macrophages	[37, 41, 42]
	Dendritic cells	[38]
	T cells	[39]
	Unknown target cells
	Idoleamine desoxygenase	[43]
	Prostaglandin E2	[37, 41]
Elimination mechanisms?	Antibody formation	[6]
	Phagocytes	[102]
Influence of radiation on homing?	Increased in brain, heart, bone marrow, and muscles	[43, 82]
Homing in malignancies?	Tumor	[83–85, 87–92]
	Mediated by CCL25	[88]
	Mediated by sodium iodide symporter under the control of RANTES/CCL-5 promoter	[87]
	Homed MSCs form tumor-associated fibroblasts	[90]
Formation of microvesicles	Microvesicles may contribute to/be part of MSC biodistribution	[14, 63, 93–97]
Formation of microvesicles	Mediated by horizontal transfer of microRNAs	[96]

ISSN: 1757-6512