Fig. 4.

Selective recruitment of hMSCs by metastatic loci. The recruitment of hMSCs towards liver and lung with or without metastatic disease was compared and detected by fluorescence signal by harvesting the mice organs on Day 56 after orthotopic tumor engraftment. The neuroblastoma metastasis in liver (n = 3, representative results) and lung (n = 3) was detectable by bio-luminescence using in vivo imaging system, (a, c). Liver metastatic loci could be directly observed in gross tumors ex vivo, representative results (b). hMSCs could be selectively attracted by liver (a) and lung (c) invaded by neuroblastoma cells. None could be detected in the liver (a) and lung (c) without tumor metastasis, representative results