Aims/hypothesis: We sought to establish if stem cells contained in cord blood cell allografts have the capacity to differentiate into insulin-expressing beta cells in humans. Methods: We studied pancreases obtained at autopsy from individuals (n=11) who had prior opposite-sex cord blood transplants to reconstitute haematopoiesis. Pancreatic tissue sections were stained first by XY-fluorescence in situ hybridisation and then insulin immunohistochemistry. Pancreases obtained at autopsy from participants without cord blood cell infusions served as controls (n=11). Results: In the men with prior transplant of female cord blood, there were 3.4±0.3% XX-positive insulin-expressing islet cells compared with 0.32±0.05% (p<0.01) in male controls. In women with prior transplant of male cord blood cells we detected 1.03±0.20% XY insulin-expressing islet cells compared with 0.03±0.03 in female controls (p<0. 001). Conclusions/interpretation: Cord blood stem cells have the capacity to differentiate into insulin-expressing cells in non-diabetic humans. It remains to be established whether these cells have the properties of beta cells.
Bibliographical noteFunding Information:
Acknowledgements Studies were supported by grants from the National Institute of Health (DK059579) and the Larry Hillblom Foundation. We thank E. Manesso for her statistical advice, J. Jang for help in image acquisition and K. Linzmeier for her help in measuring the nuclear diameter. We are grateful to H. Cox and R. Galasso from the Larry Hillblom Islet Research Center and M. Torres and S. Cucueco from the Cytogenetics Laboratory for their excellent technical support and acknowledge the support and excellent suggestions of our colleagues at the Larry Hillblom Islet Research Center, A. Bhushan, T. Gurlo and S. Georgia.
- Beta cell
- Cord blood cell
- Stem cell