Mikroenkapsüle edilen paratiroid hücrelerinin omentuma naklinde hiperterminin etkisi / The effect of hyperthermia on the transplantation of microencapsulated parathyroid cells to the omentum

Abstract

Hypoparathyroidism is an endocrine disorder characterized by high phosphorus and low levels of calcium and parathormone. Injury of the parathyroid glands during thyroid or other head and neck surgeries, or complete removal of the parathyroid glands (associated with the surgical method that should be applied especially in secondary and tertiary hyperparathyroidism, while accidentally occurring in thyroidectomy) are the most common causes of hypoparathyroidism. As a conventional treatment, calcium, vitamin D, phosphate and magnesium preparations are used. There are also recombinant parathormone drugs. However, animal studies have shown that long-term treatment is also associated with the development of bone tumors. In addition, not every patient can access it due to its high costs. The most physiological and potential definitive treatment for persistent hypoparathyroidism is to restore parathyroid tissue to regenerate calcium homeostasis. Therefore, the most effective, permanent and viable treatment method is parathyroid cell transplantation. In the literature, three basic techniques for parathyroid transplantation have been described: direct transplantation, transplantation of cultured cells and transplantation of microencapsulated cells. Direct transplantation technique is the oldest technique and is not preferred today due to the fact that it requires permanent immunosuppression, and has low success rate and survival. In the transplantation of cultured cells, the success rate is limited and the survival is not very long. Both the failure to increase the success rate and the lack of long survival in successful transplants are explained by the presence of immune defense cells. The highest success rate without permanent immunosuppression is achieved by microencapsulation techniques. Already the highest success rate is observed after the application of microencapsulation.With this process, parathyroid cells can be transferred to the omentum by microencapsulating with various bio-compatible materials in order to protect them from the immune system. As BVU Parathyroid Transport Unit, in vivo and in vitro studies related to microencapsulation have been completed and microencapsulation transplantation has been carried out to patients since 2016. With the microencapsulation method, the survival time is extended. However, as shown in our studies, fibrosis is seen around the capsules over time, and the capsules may therefore lose their efficiency. In this study; it is aimed to increase the efficiency of the microencapsulation technique and to optimize the transplantation process. For this purpose, the efficiencies of the capsules will be tested by in vivo conditions and at different temperatures and data will be provided for human parathyroid transplantation in the later period according to the results to be obtained.