Role of Procoagulant Activity (PCA) in Allograft Rejection
Gary A. Levy, Edward H. Cole in Procoagulant Activity in Health and Disease, 2019
Allotransplantation of an organ creates an artificial situation in which the activity of normal and appropriately reacting defense mechanisms of the immune system results in allograft rejection.1 Rejection of an allograft is initiated by the recognition of graft histocompatibility antigens.2–4 Transplantation antigens are cell surface structures that constitute the major immunologic barrier to successful transplantation. The major transplantation antigens are coded by a set of closely linked loci called the major histocompatibility complex (MHC), which is located on chromosome 6 in humans and on chromosome 17 in mice.5–7 The transplantation antigens are referred to as human leukocyte antigens (HLA) in humans, H-2 antigens in mice, and RT antigens in rats.7,8 The rapidity of the rejection of organ grafts between individuals of the same species (allografts) has been demonstrated to be inversely proportional to the degree of histocompatibility between individuals.8–10 Grafts between different species (xenografts) are rejected more promptly, whereas grafts from identical twins (isografts) and from an individual to himself (autografts) survive indefinitely if the vascular supply has been reestablished.3,4
Lung Transplantation in the Rat *
Waldemar L. Olszewski in CRC Handbook of Microsurgery, 2019
Clinical lung transplantation has not reached the same success as transplantation of organs like kidney, heart, and liver. In only 4 of the 39 transplanted patients the graft functioned for 1 month and none functioned for 1 year.1 The most important cause of failure was rejection.2–4 An important feature of the lung is that, in contrast with most other organs, it contains a considerable amount of lymphoid tissue5 providing a large pool of passenger leukocytes augmenting the immunogenicity of a lung allograft.6 So one of the major problems in lung transplantation is an immunological one. To study the immunological aspects of lung allotransplantation an immunogenetically well-defined transplantation model is necessary. This can be achieved by the use of inbred rats instead of dogs or monkeys, commonly used in lung transplantation research. For this purpose we developed a technique in the rat for orthotopic left lung transplantation.7,8 This report compiles our experience with over 500 transplantations during a 4-year period.
Hieh-Dose Immunosuppressive Chemotherapy with Autologous Stem Cell Support for Chronic Autoimmune Thrombocytopenia
Richard K. Burt, Alberto M. Marmont in Stem Cell Therapy for Autoimmune Disease, 2019
Finally, the potential benefit of graft-vs.-autoimmunity effect that could be provided by allotransplantation may deserve further investigation. Marmont and colleagues treated a patient with Evans syndrome by allogeneic reduced intensity transplantation and graded incremental donor lymphocyte infusions.64 They were able to achieve donor chimerism associated with grade II graft-vs.-host disease and complete clinical and biological remission of autoimmunie cytolysis in this patient. Further case series and/or formal trials of this approach with longer follow-up will be needed in order to better assess whether such a mechanism may contribute to remission of AITP to justify the risks of allogeneic transplantation.
The effects of triptolide on the cellular activity of cryopreserved rat sciatic nerves and nerve regeneration after allotransplantation
Published in International Journal of Neuroscience, 2020
Yi Wang, Song Zhang, Zijian Li, Huanhuan Zeng, Hua Xian, Yingru Huang
Autologous nerve transplantation is the most commonly used method for treating peripheral nerve defects (particularly long-segment nerve defects). However, unforeseen issues, such as limited sources of nerves and the induction of new nerve defects, restrict the clinical application of this method. Allogeneic nerves may be the best substitute for autologous nerves because they maintain the same tissue structure as autologous nerves [1,2]. Successful in vitro preservation is required for the clinical application of allotransplantation. However, the ischemic, hypoxic and low-temperature environments encountered during the in vitro preservation of peripheral nerves can cause tissue and cell injury, resulting in the reduced activity or even death of Schwann cells (SCs). SCs are the major structural and functional cells in peripheral nerves; they secrete various neurotrophic factors and adhesion molecules and are important for axonal regeneration after nerve injury [3,4]. Therefore, the biological activities of SCs must be maintained after in vitro preservation of peripheral nerves.
The decellularized ovary as a potential scaffold for maturation of preantral ovarian follicles of prepubertal mice
Published in Systems Biology in Reproductive Medicine, 2021
Sanaz Alaee, Raheleh Asadollahpour, Abasalt Hosseinzadeh Colagar, Tahereh Talaei-Khozani
In decellularized tissues, the living cells of an organ are removed and the ECM is left nearly intact, explaining the trend toward their use in regenerative medicine. The lack of cells and low immunogenicity of these reconstructed tissues make them a good choice for allotransplantation and even xenotransplantation (Liu et al. 2017). The decellularization technique also provides a good vehicle for follicular development in constructing artificial ovaries. Therefore, the current study aimed to evaluate the potential of the decellularized ovary to support ovarian follicle growth and maturation while determining the efficiency of a xenosource of ECM in follicular maturation. For this purpose, preantral follicles of prepubertal mice cultured in 2D and decellularized ovaries of mature rats to reach the antral stage. Finally, follicle survival rate, antrum formation rate, oocyte maturation, and levels of estradiol and progesterone were evaluated in both culture systems. In addition, follicle diameters and expression of a major group of follicular growth genes including zona pellucida 2 (ZP2), growth/differentiation factor-9 (Gdf9), bone morphogenetic protein 6(Bmp6), and bone morphogenetic protein 15 (Bmp15) were evaluated in 2D and 3D systems and compared with the in vivo condition.
Immunological heterogeneity of healthy peripheral blood stem cell donors – preharvesting donor characteristics, additional heterogeneity induced by granulocyte colony-stimulating factor and possible importance for outcome after allotransplantation
Published in Expert Review of Hematology, 2018
Øystein Bruserud, Guro K. Melve, Tobias Gedde-Dahl, Tor Henrik Anderson Tvedt
An optimal selection of the stem cell donor is essential for outcome after allotransplantation, and among the established donor risk factors are major histocompatibility complex mismatches, female donor for male recipient, and killing immunoglobulin-like receptor genotype [1]. However, additional donor factors may also have an impact, including the mobilizing treatment with granulocyte colony-stimulating factor (G-CSF) and its heterogeneous effects on graft composition as well as the functional status of graft immunocompetent cells. The importance of administering graft versus host disease (GVHD) prophylaxis before or early after allotransplantation [1,2] clearly illustrates that the donor immunocompetent cells are infused during a time period that is critical with regard to immunoregulation and the risk of later developing severe immune-mediated complications.
Related Knowledge Centers
- Autotransplantation
- Cartilage
- Syngenic
- Tissue
- Xenotransplantation
- Organ Transplantation
- Cell
- Transplant Rejection
- Graft-Versus-Host Disease
- NON-Heart-Beating Donation