Transplant immunology
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Transplant immunology · Aug 2020
EditorialImmediate impact of COVID-19 on transplant activity in the Netherlands.
The rapid emergence of the COVID-19 pandemic is unprecedented and poses an unparalleled obstacle in the sixty-five year history of organ transplantation. Worldwide, the delivery of transplant care is severely challenged by matters concerning - but not limited to - organ procurement, risk of SARS-CoV-2 transmission, screening strategies of donors and recipients, decisions to postpone or proceed with transplantation, the attributable risk of immunosuppression for COVID-19 and entrenched health care resources and capacity. The transplant community is faced with choosing a lesser of two evils: initiating immunosuppression and potentially accepting detrimental outcome when transplant recipients develop COVID-19 versus postponing transplantation and accepting associated waitlist mortality. ⋯ Worrisome, there was a significant decrease in organ donation numbers affecting all organ transplant services. In addition, there was a detrimental effect on transplantation numbers in children with end-organ failure. Ongoing efforts focus on mitigation of not only primary but also secondary harm of the pandemic and to find right definitions and momentum to restore the transplant programs.
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Transplant immunology · Jun 2019
Observational StudyPrevalence of antibodies to lung self-antigens (Kα1 tubulin and collagen V) and donor specific antibodies to HLA in lung transplant recipients and implications for lung transplant outcomes: Single center experience.
For patients with end stage lung disease, lung transplantation (LT) remains the only definitive treatment option. Long term survival post LT is limited by acute and chronic allograft dysfunction. Antibodies to lung self-antigens Kα1Tubulin and collagen V (autoantibodies) have been implicated in adverse outcomes post LT. The aim of our study was to determine the prevalence of autoantibodies in pre- and post-transplant sera, evaluate the impact on post-transplant outcomes. ⋯ In our cohort, we observed a high prevalence of autoantibodies and DSA in lung transplant recipients. Pre-transplant autoantibodies were associated with de novo development of DSA along with a decrease in BOS-free survival. Limitations to our study include the small sample size and single center enrollment, along with limited time for follow-up.
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Transplant immunology · Feb 2019
Regulatory effects of dermal papillary pluripotent stem cells on polarization of macrophages from M1 to M2 phenotype in vitro.
The M1:M2 macrophage ratio is important for spinal cord injury (SCI) repair. Bone marrow mesenchymal stem cells (BMSCs) can alter macrophage activation, promoting M1 to M2 macrophage conversion and SCI repair; however, clinical BMSC applications have limitations. Previously, we found DPCs to be superior to BMSCs in promoting tissue repair after SCI, which we hypothesized to be mediated by M1 to M2 macrophage conversion. ⋯ The number of CD206-expressing M2 macrophages also increased. These findings demonstrate that DPCs reprogram macrophages to an anti-inflammatory M2 phenotype, which could improve adverse inflammatory microenvironments and promote tissue repair. Thus, DPCs may be an interesting alternative cell source and merit further investigation in applications for SCI therapy.
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Transplant immunology · Jun 2018
Persistent accumulation of circulating monocytic myeloid-derived suppressor cells contributes to post-infectious immunosuppression in renal transplant recipients with bacterial infection: A pilot study.
Post-infectious immunosuppression is disadvantageous to patients' long-term outcomes, especially in transplant recipients receiving large doses of immunosuppressants. A growing body of evidence indicates the immunoregulatory ability of myeloid-derived suppressor cells (MDSCs). We herein investigate the characteristics of monocytic-MDSCs (M-MDSCs) in a cohort of renal transplant recipients with/without infection to clarify the potential involvement in post-infectious immunosuppression. ⋯ Circulating M-MDSCs underwent significant and persistent increases after bacterial infection in renal transplant recipients, contributing to post-infectious immunodeficiency. Therefore, special attention should be given to M-MDSCs during the monitoring of immune status and infection management.
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Transplant immunology · Sep 2016
A chronic renal rejection model with a fully MHC-mismatched rat strain combination under immunosuppressive therapy.
The Fischer-to-Lewis (LEW) rat model of kidney transplantation is a widely accepted and well-characterized model of chronic rejection. In contrast to transplantation in a clinical setting, however, the absence of treatment with immunosuppressants and only minor mismatch of major histocompatibility complexes (MHCs) are critical discrepancies. Here, we established a rat model of chronic rejection using fully MHC-mismatched strains in which kidney disease progresses even under immunosuppressive therapy. ⋯ We established an allograft rejection model with impaired renal function and typical histopathological changes of chronic rejection in fully MHC-mismatched rats by controlling administration of an immunosuppressant. These findings suggest that this model more accurately reflects transplantation in a clinical setting than existing models and enables the evaluation of therapeutic agents.