Mesenchymal stem cells can affect solid organ allograft survival.
ABSTRACT It has recently been recognized that mesenchymal stem cells (MSCs) isolated from adult bone marrow are able to modify the alloimmune response in vitro and in vivo. MSCs can be expanded into large quantities in culture, thereby facilitating potential future applications in solid organ transplantation. To develop novel MSC-based antirejection treatments, the mechanism behind the immunomodulatory ability of MSCs has to be elucidated further. At present, a variety of possible in vitro effects of MSCs on immune system effector cells have been reported, but little is known about their in vivo properties. Here, we discuss recent findings regarding the influence of MSCs on different effector cell populations in vitro and summarize the available data describing their in vivo properties.
- Urology 01/2011; 78(3). · 2.42 Impact Factor
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ABSTRACT: Purpose To expand the limited donor pool, lung retrieval from non-heart-beating donors (NHBD) was introduced clinically. However, primary graft dysfunction with surfactant inactivation due to I/R-injury is a major cause of early mortality. Furthermore, donor-derived mesenchymal stem cell (MSC) expansion and fibrotic differentiation in the allograft results in deleterious bronchiolitis obliterans syndrome (BOS). Therefore, pretreatment of NHBD with recipient-specific bone-marrow-(BM)-derived MSC might improve postischemic surfactant function and reduce incidence of BOS by numerous parakrine, immunomodulating and tissue-remodeling properties especially on type-II-pneumocytes. Methods and Materials Asystolic pigs (n=5/group) were ventilated for 3h of warm ischemia (groups 1-3). 50x106 BM-MSC, each, were administered in pulmonary artery (group 2) or nebulized endobronchially (group 3) prior to preservation. After left-lung-transplantation grafts were reperfused for 4h. Hemodynamics (PVR), pO2/FiO2 and dynamic compliance (DLC) were compared to lungs without pretreatment (group 1) and sham-controls (Sham). To prove and localize the Texas-red labelled MSCs in the lung, PCR was performed and cryosections were counter-stained with WGA and DAPI. Intra-alveolar edema was determined sterologically. Statistics comprised ANOVA with repeated measurements. Results PVR and DLC were superior in endobronchially pretreated MSC lungs as compared to endovascular MSC application and lungs without pretreatment. Oxygenation was worst after endovascular pretreatment. Stereology revealed low intrapulmonary edema in all groups (p>0.05), successful MSC application was proven by PCR. MSC were localized in alveola and capillaries. Conclusions Intrapulmonary deposition of BM-MSC in NHBD is feasible, but only endobronchial application optimizes DLC and PVR postoperatively. Due to immunomodulatory and paracrine effects on epithelial restitution, autologous-BM-MSC-based donor pretreatment for prevention or attenuation of limiting BOS is very promising in LTx.Journal of Cardiothoracic Surgery 09/2014; 32(4):S15–S16. · 0.90 Impact Factor
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ABSTRACT: An adaptive space-time processing system for dynamic spatial channels in a CDMA mobile communications network is presented. The proposed system consists of an adaptive sensor array that estimates the desired directions and waveforms, followed by adaptive linear equalizers that refine the waveform estimates by compensating for the mobile radio uplink channel. Capacity gains are achieved through code reuse, which is made possible by performing the spatial processing after the codes have been decorrelated with one another. Simulation results for a two sensor array in a variety of interference scenarios are presented in the form of bit error rate curves.Proceedings - ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing 01/1995; 3:1749-1752.