scholarly journals The Microbiome, Systemic Immune Function, and Allotransplantation

2015 ◽  
Vol 29 (1) ◽  
pp. 191-199 ◽  
Author(s):  
Anoma Nellore ◽  
Jay A. Fishman

SUMMARYDiverse effects of the microbiome on solid organ transplantation are beginning to be recognized. In allograft recipients, microbial networks are disrupted by immunosuppression, nosocomial and community-based infectious exposures, antimicrobial therapies, surgery, and immune processes. Shifting microbial patterns, including acute infectious exposures, have dynamic and reciprocal interactions with local and systemic immune systems. Both individual microbial species and microbial networks have central roles in the induction and control of innate and adaptive immune responses, in graft rejection, and in ischemia-reperfusion injury. Understanding the diverse interactions between the microbiome and the immune system of allograft recipients may facilitate clinical management in the future.

2020 ◽  
Vol 21 (2) ◽  
pp. 631 ◽  
Author(s):  
Lina Jakubauskiene ◽  
Matas Jakubauskas ◽  
Bettina Leber ◽  
Kestutis Strupas ◽  
Philipp Stiegler ◽  
...  

In recent decades, solid organ transplantation (SOT) has increased the survival and quality of life for patients with end-stage organ failure by providing a potentially long-term treatment option. Although the availability of organs for transplantation has increased throughout the years, the demand greatly outweighs the supply. One possible solution for this problem is to extend the potential donor pool by using extended criteria donors. However, organs from such donors are more prone to ischemia reperfusion injury (IRI) resulting in higher rates of delayed graft function, acute and chronic graft rejection and worse overall SOT outcomes. This can be overcome by further investigating donor preconditioning strategies, graft perfusion and storage and by finding novel therapeutic agents that could reduce IRI. relaxin (RLX) is a peptide hormone with antifibrotic, antioxidant, anti-inflammatory and cytoprotective properties. The main research until now focused on heart failure; however, several preclinical studies showed its potentials for reducing IRI in SOT. The aim of this comprehensive review is to overview currently available literature on the possible role of RLX in reducing IRI and its positive impact on SOT.


2021 ◽  
Vol 22 (3) ◽  
pp. 1181
Author(s):  
Natalie Vallant ◽  
Bynvant Sandhu ◽  
Karim Hamaoui ◽  
Maria Prendecki ◽  
Charles Pusey ◽  
...  

Mesenchymal Stromal Cells (MSC) have been shown to exhibit immuno-modulatory and regenerative properties at sites of inflammation. In solid organ transplantation (SOT), administration of MSCs might lead to an alleviation of ischemia-reperfusion injury and a reduction of rejection episodes. Previous reports have suggested ‘MSC-preconditioning’ of macrophages to be partly responsible for the beneficial effects. Whether this results from direct cell-cell interactions (e.g., MSC trans-differentiation at sites of damage), or from paracrine mechanisms, remains unclear. Immunosuppressive capacities of MSCs from donors of different age and from genetically modified donor animals, often used for in-vivo experiments, have so far not been investigated. We conducted an in vitro study to compare paracrine effects of supernatants from MSCs extracted from young and old wild-type Wystar-Kyoto rats (WKY-wt), as well as young and old WKY donor rats positive for the expression of green fluorescent protein (WKY-GFP), on bone marrow derived macrophages (BMDM). Expression levels of Mannose receptor 1 (Mrc-1), Tumor necrosis factor α (TNFα), inducible NO synthase (iNos) and Interleukin-10 (IL-10) in BMDMs after treatment with different MSC supernatants were compared by performance of quantitative PCR. We observed different expression patterns of inflammatory markers within BMDMs, depending on age and genotype of origin for MSC supernatants. This must be taken into consideration for preclinical and clinical studies, for which MSCs will be used to treat transplant patients, aiming to mitigate inflammatory and allo-responses.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Wei Li ◽  
Zihui Meng ◽  
Yuliang Liu ◽  
Rakesh P. Patel ◽  
John D. Lang

Liver ischemia-reperfusion injury is a major cause of primary graft non-function or initial function failure post-transplantation. In this study, we examined the effects of sodium nitrite supplementation on liver IRI in either Lactated Ringer's (LR) solution or University of Wisconsin (UW) solution. The syngeneic recipients of liver grafts were also treated with or without nitrite by intra-peritoneal injection. Liver AST and LDH release were significantly reduced in both nitrite-supplemented LR and UW preservation solutions compared to their controls. The protective effect of nitrite was more efficacious with longer cold preservation times. Liver histological examination demonstrated better preserved morphology and architecture with nitrite treatment. Hepatocellular apoptosis was significantly reduced in the nitrite-treated livers compared their controls. Moreover, liver grafts with extended cold preservation time of 12 to 24 hours demonstrated improved liver tissue histology and function post-reperfusion with either the nitrite-supplemented preservation solution or in nitrite-treated recipients. Interestingly, combined treatment of both the liver graft and recipient did not confer protection. Thus, nitrite treatment affords significant protection from cold ischemic and reperfusion injury to donor livers and improves liver graft acute function post-transplantation. The results from this study further support the potential for nitrite therapy to mitigate ischemia-reperfusion injury in solid organ transplantation.


2020 ◽  
Vol 21 (18) ◽  
pp. 6607
Author(s):  
Mindaugas Kvietkauskas ◽  
Viktorija Zitkute ◽  
Bettina Leber ◽  
Kestutis Strupas ◽  
Philipp Stiegler ◽  
...  

In solid organ transplantation (Tx), both survival rates and quality of life have improved dramatically over the last few decades. Each year, the number of people on the wait list continues to increase, widening the gap between organ supply and demand. Therefore, the use of extended criteria donor grafts is growing, despite higher susceptibility to ischemia-reperfusion injury (IRI) and consecutive inferior Tx outcomes. Thus, tools to characterize organ quality prior to Tx are crucial components for Tx success. Innovative techniques of metabolic profiling revealed key pathways and mechanisms involved in IRI occurring during organ preservation. Although large-scale trials are needed, metabolomics appears to be a promising tool to characterize potential biomarkers, for the assessment of graft quality before Tx and evaluate graft-related outcomes. In this comprehensive review, we summarize the currently available literature on the use of metabolomics in solid organ Tx, with a special focus on metabolic profiling during graft preservation to assess organ quality prior to Tx.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Pascal Rowart ◽  
Pauline Erpicum ◽  
Olivier Detry ◽  
Laurent Weekers ◽  
Céline Grégoire ◽  
...  

Ischemia/reperfusion injury (IRI) represents a worldwide public health issue of increasing incidence. IRI may virtually affect all organs and tissues and is associated with significant morbidity and mortality. Particularly, the duration of blood supply deprivation has been recognized as a critical factor in stroke, hemorrhagic shock, or myocardial infarction, as well as in solid organ transplantation (SOT). Pathophysiologically, IRI causes multiple cellular and tissular metabolic and architectural changes. Furthermore, the reperfusion of ischemic tissues induces both local and systemic inflammation. In the particular field of SOT, IRI is an unavoidable event, which conditions both short- and long-term outcomes of graft function and survival. Clinically, the treatment of patients with IRI mostly relies on supportive maneuvers since no specific target-oriented therapy has been validated thus far. In the present review, we summarize the current literature on mesenchymal stromal cells (MSC) and their potential use as cell therapy in IRI. MSC have demonstrated immunomodulatory, anti-inflammatory, and tissue repair properties in rodent studies and in preliminary clinical trials, which may open novel avenues in the management of IRI and SOT.


2019 ◽  
Vol 20 (8) ◽  
pp. 823-828 ◽  
Author(s):  
Songjie Cai ◽  
Jing Zhao ◽  
Takuya Ueno ◽  
Anil Chandraker

Siglecs are mammalian sialic acid (Sia) recognizing immuno-globulin-like receptors expressed across the major leukocyte lineages, and function to recognize ubiquitous Sia epitopes on the cell surface. Many Siglecs are inhibitory receptors expressed on innate immune cells, they also have a role in maintaining B cell tolerance as well as modulating the activation of conventional and plasmocytic dendritic cells. Through these and other roles they contribute directly and indirectly to the regulation of T cell function. Siglecs have been identified to play key roles in several forms of blood cancers, autoimmune and infection deceases. So far as we know, there’s no Siglecs related research works on solid organ transplantation. In this review, we describe our understanding of the potential roles of Siglecs in the regulation of immune cell function, which may be crosslinked to allo-rejection and ischemia-reperfusion injury.


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