Fig. 2

Fate of the IP injected mesenchymal stem cells in the peritoneal cavity. a Changes in the numbers of single GFP-positive cells and total single cells in the peritoneal cavity after intraperitoneal administration of GFP-MSC into BALB/c mice. The cells were recovered by a 5 ml wash of the peritoneal cavity with PBS. The resulting lavage was gently mixed and the single cells counted in a hemocytometer (n = 4, mean ± SEM). b Fluorescent images of single GFP-MSC in the hemocytometer chamber; magnification 20×. c Total number of human cells in pellets of peritoneal lavage (PLP), random sampling of about 25 mg or about 10 % of mesentery (MT), omentum (OM), jejunal lymph nodes (JLN) and spleen (SP). To collect PLP, peritoneal lavage was collected by washing the peritoneal cavity first with 1 ml and then with 5 ml of sterile PBS. The two samples of lavage were centrifuged at 500 × g for 5 min and the pellets were combined. Human cells in the samples were assayed by real-time RT-PCR for human GAPDH mRNA normalized to total eukaryotic 18S. Data points represent arithmetic means ± SEM, n = 3–5. Insert indicates human cell numbers in the spleen and jejunal lymph nodes. Note dramatic differences in cell numbers between the insert and the large panel. GFP green fluorescent protein, MSC mesenchymal stem cells