Scientific Report 2003-2004 - Cleveland Clinic Lerner Research ...

THE M. SIEMIONOWLABORATORYRESEARCH FELLOWSYavuz Demir, M.D.Selahattin Ozmen, M.D.Maciej Zielinskii, M.D.POSTDOCTORAL FELLOWSDariusz Izycki, M.D., Ph.D.TECHNOLOGY ASSISTANTSJennifer Mule, B.S.Emilia SierkoMEDICAL STUDENTSKrzysztof Siemionow, M.D.Howard YoungCOLLABORATORSTatiana Byzova, Ph.D.. 1Paul E. DiCorleto, Ph.D. 2Robert L. Fairchild, Ph.D. 3David Hicks, M.D. 4Jaroslaw Maciejewski, MD., Ph.D. 51Dept. of Mole. Cardiology, CCF2Dept. of Cell Biology, CCF3Dept. of Immunology, CCF4Dept. of Anat. Pathology, CCF5Taussig Cancer Center, CCFMaria Siemionow, M.D.,Ph.D., D.Sc.The Microsurgery Laboratory of theDepartment of Plastic and ReconstructiveSurgery has a broad research focus andincludes studies related to the followingcategories:TransplantationThe major focus of our MicrosurgeryLaboratory has been on induction of tolerance incomposite tissue allografts. CTAs comprise acombination of skin, subcutaneous tissue,neurovascular tissue, and mesenchymal tissuesuch as bone, muscle, fascia and cartilage (e.g.,the hand, knee joint or larynx). Although“nonvital to life,” these tissues are structurally,functionally and aesthetically important to thosewho specialize in functional restoration ofmusculoskeletal defects. Most attempts atcomposite tissue transplantation have beenunsuccessful, which illustrates the difficultbarrier associated with vascularized allograftscomposed of a variety of tissues. Severalexperimental designs of tolerance induction havebeen reported. Side effects related to theseprotocols limit their use to only carefully selectedapplications.Our recent approach to induce tolerance isbased on the pivotal role of T cells in allograftrejection. To create a window of immunologicalincompetence, we are investigating the possibilityof specifically eliminating alpha-beta-T-cellreceptor-positive cells, which confer the abilityto reject allograft tissues. We achieved significantdepletion of this T-cell population at theend of immunodepleting therapy and observedthe potential for repopulation of the recipient Tcells’ repertoire once the treatment protocol wasstopped. This allowed for over 700 days ofallograft survival without chronic immunosuppression.The functional outcome of CTAs isassessed by our standardized technique, includingOrtak, T., Oke, R., Unsal, M., Carnevale, K., and M. Siemionow (2001) A model ofvascular thymus transplantation in athymic rats. Transplant. Proc. 33:372-374.Meirer, R., Babuccu, O., Unsal, M., Nair, D.R., Gurunluoglu, R., Skugor, B., Meirer, B.,and M. Siemionow (2002) Effect of chronic cyclosporine administration on peripheral nerveregeneration: a dose-response study. Ann. Plastic Surg. 49:96-103.Byzova, T.V., Goldman, C.K., Jankau, J., Chen, J., Cabrera, G., Achen, M.G., Stacker,S.A., Carnevale, K.A.., Siemionow, M., Deitcher, S.R., and P.E. DiCorleto (2002)Adenovirus encoding vascular endothelial growth factor-D induces tissue-specific vascularpatterns in vivo. Blood 99:4434-4442.Siemionow, M., and K. Ozer (2002) Advances in composite tissue allograft transplantationas related to the hand and upper extremity. J. Hand Surg. [Am] 27:565-580.The Department of ImmunologyMicrosurgery Studies Focus onInduction of Transplant Tolerance andReturn of Functionclinical tests and electrophysiological methods.We evaluate the hemodynamics of the rejectingand surviving allografts at the microcirculatorylevel using our intravital microscopy system.Microvascular permeability is monitoredfollowing FITC albumin injection underfluorescence microscopy.Our newest approach is directed towardevaluating the role of bone-marrow-derived stemand proprietor cells in tolerance inductionfollowing vascularized bone-marrow transplantation.These findings will increase our understandingof mechanisms involved in CTA rejection,tolerance induction, development of GVHD andoptimization of clinically applicable treatmentprotocols.MicrocirculationOur work focuses on ischemia-reperfusioninjury and the hemodynamic effects of TNFalpha,VEGF 165 and angiopoietin 1 on thecremaster muscle’s microcirculation. Ourintravital microscopy system measures RBCvelocity, vessel diameters, capillary density andleukocyte endothelial interactions (rolling,sticking, transmigrating leukocytes), andendothelial edema index as we evaluate vascularpermeability. The new cremaster muscletransplantation model was established and istested in TNF-alpha Receptor I, II and I + IIknock-out mouse models.Nerve RegenerationWe are evaluating different surgicaltechniques used for enhancing nerve regeneration.We are studying the effect of Cyclosporine A onnerve degeneration, as well as the effect ofdifferent enhancing factors (such as DHEA andVEGF 165) on nerve regeneration in normal anddiabetic rats, using the standard clinical andfunctional tests, such as somatosensory evokedpotentials, motor evoked potentials, walkingtrack analysis, pin-prick test, and toe spread test.Nerve morphometry of EM sections is assessed byour computerized system, which measures totalnumber of myelinated axons, axon diameters,cross sectional area and myelin thickness.Wound HealingThis category involves the induction ofangiogenesis in abdominal skin flaps and a limbischemia model by the recombinant adenovirusVEGF 165. The effect of pre-operative vs. postoperativeradiation on wound healing is studiedon the rat TRAM flap model.96