The Effects Of Irreversible Electroporation (ire) On Cells, Muscles And Nerves

BackgroundMicrowave ablation has been applied on limb salvage surgeries of malignant bone tumour. There is not such a discrepancy as mechanicalness out of run in conventional artificial prosthetic replacement. Microwave ablation in malignant bone tumour has developed a new way in biological reconstruction. But after thermal ablation on bone tumour, there is no osteoinductive in residual bone, and the revascilarization is a long and slow-moving procedure. Some patients may suffer bone fracture and will need long-term rehabilitation. We want to draw into new ablation therapy, irreversible electroporation (IRE) to solve these issues. The advantages of IRE include induced complete ablation with well-demarcated margin at cell level and preservation of vital structures and protein activity within ablationed zone. IRE may solve these problems and could expand the application of limb salvage surgeries.Objective We have designed three experiments to testify the efficacy of IRE respectively at cell and tissue level. We also observed the effects of IRE on nerves.Methods1.We applied IRE on human osteosarcoma cell line SOSP-9607. The pulse length was 100μs and the pulse interval was 100ms. We want to observe the effects of different electrical field strength and pulse numbers in IRE and to preliminarily measure the threshold value of IRE ablation on osteosarcoma cell by cell trypan blue staining, CCK-8 cytoactive detection and cell toluidine blue staining.2.We applied IRE on rat gastrocnemius muscles. The electrical field strength was approximate 3000V/cm, pulse length 100μs and the pulse number was 10. We want to observe the effects of IRE on muscle tissue and to testify the advantages of IRE compared with other forthcoming tumour ablation therapies by observation in general and HE staining.3.We applied IRE on rat sciatic nerves. The electrical field strength was approximate 3000V/cm, pulse length 100μs and the pulse number was 10. We want to observe the effects of IRE on nerves and nerve regeneration after IRE by SFI calculated with walking pace analysis, electrophysiological evaluation, sciatic nerve HE staining, transmission electron micrographs analysis, toluidine blue staining, and gastrocnemius muscles HE staining.Results1.IRE with 1000V/cm 60 pulses and 1500V/cm 30 pulses can completely destroy osteosarcoma cell SOSP-9607. There was no tumour cell proliferation after continuous incubation 24 hours by CCK-8 cytoactive detection and toluidine blue staining. Although only seldom cells survived immediately after IRE with 1000V/cm 30 pulses, there was a certain proliferation after continous incubation 24 hours in this group. IRE ablation is effective on cells.2.There was well-demarcated margin between ablation zone treated with IRE and normal tissue nor only in general but also at cell level in histology. Muscle cells suffered apoptosis and disintegration. The IRE ablation is effective on tissues. The results testify some advantages of IRE ablation on tissues, including effectiveness, inducing cell apoptosis, short time ablation, preservation of vital structures, no influence on vessels and distinctness of ablation zone.3.Rat sciatic nerves treated with IRE suffered temporary nerve function loss. But we found the nerves regained total regeneration and complete function 7 weeks after injury by electrophysiological evaluation, histologic and morphometric analysis and behavioral analysis.ConclusionsIRE may become an effective therapy on musculockeletal tumor. The application of IRE on bone tumour may expand the application of limb salvage therapy.