Long-Term Quantitative Biodistribution and Side Effects of Human Mesenchymal Stem Cells (hMSCs) Engraftment in NOD/SCID Mice following Irradiation
Table 3
Levels of hMSC engraftment at 4 different time points after abdominal irradiation at 8.5 Gray.
Organs (positive per mice)
Days after irradiation
3 days
15 days
30 days
60 days
Brain
4/10 (40%)
10/10 (100%)
2/6 (33%)
1/10 (10%)
Heart
2/10 (20%)
5/10 (50%)
4/6 (67%)
4/10 (40%)
Lung
7/10 (70%)
10/10 (100%)
4/6 (67%)
2/10 (20%)
Liver
1/10 (10%)
10/10 (100%)
5/6 (83%)
0/10 (0%)
Spleen
3/10 (30%)
10/10 (100%)
5/6 (83%)
2/10 (20%)
Abdominal area
Kidney
3/10 (30%)
10/10 (100%)
4/6 (67%)
2/10 (20%)
Muscle
1/10 (10%)
2/10 (20%)
6/6 (100%)
1/6 (17%)
Stomach
1/10 (10%)
9/10 (90%)
5/6 (83%)
0/8 (0%)
Duodenum
0/10 (0%)
2/10 (20%)
2/6 (33%)
1/10 (10%)
Jejunum
1/10 (10%)
10/10 (100%)
4/6 (67%)
1/10 (10%)
Ileum
1/10 (10%)
1/10 (10%)
2/6 (33%)
1/10 (10%)
Cecum
0/10 (0%)
1/10 (10%)
1/6 (17%)
1/10 (10%)
Proximal colon
0/10 (0%)
1/10 (10%)
2/6 (33%)
3/10 (30%)
Distal colon
0/10 (0%)
1/10 (10%)
2/6 (33%)
2/10 (20%)
Posterior leg (right)
Skin
0/10 (0%)
1/10 (10%)
0/6 (0%)
0/10 (0%)
Muscle
1/10 (10%)
4/10 (40%)
2/6 (33%)
1/8 (12.5%)
Bone
1/10 (10%)
3/10 (30%)
5/6 (83%)
5/10 (50%)
Bone marrow
0/10 (0%)
10/10 (100%)
3/6 (50%)
4/8 (50%)
Blood
0/10 (0%)
3/10 (30%)
0/6 (0%)
0/10 (0%)
Number of positive organs
23/190
102/190
58/114
31/186
Frequency
12%
54%
51%
17%
The biodistribution of human cells is maximum at 15 days. hMSC engraftment is detectable from 3 days after irradiation to at least 60 days. hMSC engraftment varies from 12% of organs at day 3, 54% on D15, 51% on D30, to 17% at day 60. The homing of human cells appeared to increase up to day 15 and then decreased with time.