Although organ transplants have been applied for decades, outcomes of somatic cell transplants remain disappointing, presumably due to lack of appropriate supporting stromal cells. Thus, cotransplantation with liver stromal cells, hepatic stellate cells (HSC), achieves long-term survival of islet allografts in mice by way of induction of effector T cell apoptosis and generation of regulatory T (Treg) cells. In this study we provide evidence both in vitro and in vivo that HSC can promote generation of myeloid-derived suppressor cells (MDSC). HSC-induced MDSC demonstrate potent immune inhibitory activity. Induction of MDSC is dependent on an intact interferon gamma signaling pathway in HSC and is mediated by soluble factors, suggesting that the specific tissue stromal cells, such as HSC, play a crucial role in regulating immune response by way of inflammation-induced generation of MDSC. Large amounts of MDSC can be propagated in vitro from bone marrowderived myeloid precursor cells under the influence of HSC. Conclusion: Cotransplantation with in vitro generated MDSC can effectively protect islet allografts from host immune attack. Local delivery of potent immune suppressor cells for cell transplants holds great clinical application potential. (HEPATOLOGY 2011;53:1007-1019

Adjunctive HBOT improved wound healing in persons with DFU. Therapy also reduced the risk of amputation of the affected limb. We assert that at least 20 HBOT sessions are required to be effective.