Immunomodulatory effects of pre-irradiated extremity allograft in the rodent model

From Lab to Limb: Unraveling Translational Insights and Significance of Animal Models in Lower Extremity Transplantation

The advancements in medicine throughout the twentieth century have been largely attributed to animal studies. The initial step in researching an animal disease is to establish a model closely resembling the clinical circumstances in humans. Consequently, an excellent animal model is essential for almost any experimental research. The aim of this review is to evaluate the current research on animal models for lower extremity transplantation (LET) and determine how pertinent and significant these models are for therapeutic settings. To bring the reader up to date from an allotransplantation standpoint, we also review, assess, and highlight the noteworthy and intriguing results of the clinical cases performed so far and various animal models. The discussion of their clinical applicability and practicality in the present and future has shed light on the experience with vascularized composite allotransplantation (VCA) around the globe.

Use of FK506 and bone marrow mesenchymal stem cells for rat hind limb allografts

Dark Agouti rat donor hind limbs were orthotopically transplanted into Lewis rat recipients to verify the effects of bone marrow mesenchymal stem cells on neural regeneration and functional recovery of allotransplanted limbs in the microenvironment of immunotolerance. bone marrow mesenchymal stem cells were intramuscularly (gluteus maximus) injected with FK506 (tacrolimus) daily, and were transplanted to the injured nerves. Results indicated that the allograft group not receiving therapy showed severe rejection, with transplanted limbs detaching at 10 days after transplantation with complete necrosis. The number of myelinated axons and Schwann cells in the FK506 and FK506 + bone marrow mesenchymal stem cells groups were significantly increased. We observed a lesser degree of gastrocnemius muscle degeneration, and increased polymorphic fibers along with other pathological changes in the FK506 + bone marrow mesenchymal stem cells group. The FK506 + bone marrow mesenchymal stem cells group showed significantly better recovery than the autograft and FK506 groups. The results demonstrated that FK506 improved the immune microenvironment. FK506 combined with bone marrow mesenchymal stem cells significantly promoted sciatic nerve regeneration, and improved sensory recovery and motor function in hind limb allotransplant.