Background: The development of long-term allograft survival and understanding the mechanism(s) by which it is induced are major goals of experimental transplantation. Studies by several different investigators have provided conflicting evidence for the role of interleukin (IL)-4 in the process of allograft rejection or long-term allograft survival. These studies examine the role of IL-4 in experimental cardiac allograft rejection and in inducing long-term allograft survival. A possible mechanism for long-term allograft maintenance via alternative allosensitization is discussed.
Methods: Adult IL-4-intact or IL-4-deficient (knockout, KO) C57BL/6 (B6) mice were transplanted with heterotopic DBA/2 cardiac allografts and immunosuppressed either with gallium nitrate (GN), or the anti-CD4 monoclonal antibody, GK1.5. Cellular allosensitization was assessed by testing the allograft recipients for donor-reactive delayed-type hypersensitivity (DTH) responses. The presence of antigen-driven suppressive mechanisms was assessed using a linked unresponsiveness (bystander suppression) DTH assay.
Results: In general, the results were the same with either GN or GK1.5. We observed that (1) IL-4 is not required for acute allograft rejection or allogeneic DTH responses in nonsuppressed mice, (2) IL-4 is required for long-term allograft survival in immunosuppressed mice, (3) immunosuppression creates a requirement for IL-4 in major histocompatibility complex self-restricted, but not allorestricted, DTH responses, and (4) the development of alloantigen-dependent linked DTH unresponsiveness (bystander suppression) in allograft recipients requires IL-4.
Conclusion: In summary, these studies demonstrate a common requirement for IL-4 during the development of long-term allograft survival and the concurrent development of alloantigen-dependent DTH down-regulation in cardiac allograft recipients after immunosuppression.
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http://dx.doi.org/10.1097/00007890-199805270-00012 | DOI Listing |
BMC Oral Health
January 2025
State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Implant Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
Purpose: This study aimed to evaluate the osteogenic performance of allograft particulate bone and cortical bone blocks combined with xenograft under bovine pericardium membranes, for treating different degrees of labial bone defects in the aesthetic zone.
Materials And Methods: Twenty-four patients with bone defects were divided into two groups based on defect severity (Terheyden 1/4 and 2/4 groups). The Terheyden 1/4 group received granular bone grafts alone, while the Terheyden 2/4 group received cortical bone blocks combined with granular bone grafts.
Microorganisms
December 2024
Cell Factory, Department of Mother and Child Health, Fondazione IRCCS Policlinico S. Matteo, 27100 Pavia, Italy.
Polyomavirus BK (BKPyV)-associated nephropathy (BKPyV-nephropathy) remains a significant cause of premature kidney allograft failure. In the absence of effective antiviral treatments, current therapeutic approaches rely on immunosuppression (IS) reduction, possibly at the risk of inducing alloimmunity. Therefore, we sought to explore the long-term effects of a tailored viro-immunologic surveillance and treatment program for BKPyV on the development of alloimmunity and kidney graft outcome.
View Article and Find Full Text PDFClin Oral Investig
January 2025
Department of Surgical Sciences and Integrated Diagnostics, Unit of Implant and Prosthetic Dentistry, University of Genoa, Largo R. Benzi 10 , 16121 , Genova, Italy.
Objectives: Successful implant therapy must also ensure the integration of the soft tissues around the crown/abutment emergence profile. The existing literature does not consistently agree on the necessity of a minimal amount of keratinized tissue (KT), though it appears advantageous for the long-term stability and aesthetics of implants. The purpose of this clinical retrospective study is to compare the effectiveness of amnion/chorion membrane and autogenous subepithelial connective tissue in increasing the keratinized mucosa and maintaining it over a 5-year follow-up.
View Article and Find Full Text PDFPLoS One
January 2025
Transplant Group, La Paz University Hospital Health Research Institute (IdiPAZ), Madrid, Spain.
Background: Intestinal transplantation (ITx) represents the only curative option for patients with irreversible intestinal failure. Nevertheless, its rejection rate surpasses that of other solid organ transplants due to the heightened immunological load of the gut. Regulatory T-cells (Tregs) are key players in the induction and maintenance of peripheral tolerance, suggesting their potential involvement in modulating host vs.
View Article and Find Full Text PDFJ Plast Reconstr Aesthet Surg
November 2024
Yale School of Medicine, Division of Reconstructive and Plastic Surgery, New Haven, CT, USA. Electronic address:
Background: The long-term stability of allograft or native bone in facial vascularized composite allograft (fVCA) recipients is unclear. This study quantified long-term bone volume changes in facial transplants.
Methods: Computed tomography scans of eight fVCA recipients (2011-2023) were analyzed with Materialise Mimics.
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