Organ transplantation: historical perspective and current practice

Biomaterial-enhanced treg cell immunotherapy: A promising approach for transplant medicine and autoimmune disease treatment

Regulatory T cells (Tregs) are crucial for preserving tolerance in the body, rendering Treg immunotherapy a promising treatment option for both organ transplants and autoimmune diseases. Presently, organ transplant recipients must undergo lifelong immunosuppression to prevent allograft rejection, while autoimmune disorders lack definitive cures. In the last years, there has been notable advancement in comprehending the biology of both antigen-specific and polyclonal Tregs. Clinical trials involving Tregs have demonstrated their safety and effectiveness. To maximize the efficacy of Treg immunotherapy, it is essential for these cells to migrate to specific target tissues, maintain stability within local organs, bolster their suppressive capabilities, and ensure their intended function's longevity. In pursuit of these goals, the utilization of biomaterials emerges as an attractive supportive strategy for Treg immunotherapy in addressing these challenges. As a result, the prospect of employing biomaterial-enhanced Treg immunotherapy holds tremendous promise as a treatment option for organ transplant recipients and individuals grappling with autoimmune diseases in the near future. This paper introduces strategies based on biomaterial-assisted Treg immunotherapy to enhance transplant medicine and autoimmune treatments.

Therapy with regulatory T-cell infusion in autoimmune diseases and organ transplantation: A review of the strengths and limitations

In the last decade, cell therapies have revolutionized the treatment of some diseases, earning the definition of being the "third pillar" of therapeutics. In particular, the infusion of regulatory T cells (Tregs) is explored for the prevention and control of autoimmune reactions and acute/chronic allograft rejection. Such an approach represents a promising new treatment for autoimmune diseases to recover an immunotolerance against autoantigens, and to prevent an immune response to alloantigens. The efficacy of the in vitro expanded polyclonal and antigen-specific Treg infusion in the treatment of a large number of autoimmune diseases has been extensively demonstrated in mouse models. Similarly, experimental work documented the efficacy of Treg infusions to prevent acute and chronic allograft rejections. The Treg therapy has shown encouraging results in the control of type 1 diabetes (T1D) as well as Crohn's disease, systemic lupus erythematosus, autoimmune hepatitis and delaying graft rejection in clinical trials. However, the best method for Treg expansion and the advantages and pitfalls with the different types of Tregs are not fully understood in terms of how these therapeutic treatments can be applied in the clinical setting. This review provides an up-to-date overview of Treg infusion-based treatments in autoimmune diseases and allograft transplantation, the current technical challenges, and the highlights and disadvantages of this therapeutic approaches."

Two sides to every story: Reappraising the early history of liver transplantation at Addenbrooke's Hospital, Cambridge

Over the course of the past six decades, liver transplantation has evolved to become the treatment of choice for chronic end-stage liver disease and some cases of acute hepatic failure. Currently, more than 34,000 liver transplants are conducted worldwide per annum, and overall one year survival rates exceed 90%. However, the early years of human liver transplantation were beset by failure. Eyewitness reports from this period make for tragic, yet compelling reading. Volume 12 of The History of Anaesthesia Society Proceedings contains one such account, written by Dr Elizabeth Gibbs. This outlined the experience of single-handedly anaesthetising the recipient of the first liver transplant to be undertaken at Addenbrooke's Hospital, Cambridge, UK, in June 1967. Despite the best efforts of the team, the patient died from uncontrollable haemorrhage 19 hours after the start of the procedure. While this tragic outcome might have been expected in the early days of liver transplantation, Gibbs included an unsettling postscript in her paper. This stated that all of the patient's records had apparently been 'lost', and the date of the first Cambridge liver transplant was publicly reported as 2 May 1968, some 11 months after the events described. This article outlines the results of research aimed at critically appraising this postscript. In doing so a number of unexpected discoveries were made. These highlight some important lessons for medical historians and demonstrate that if you look hard enough, there really are two sides to every story.

Analysis on the change of gut microbiota and metabolome in lung transplant patients

Previous studies have shown that the gut microbiota and its metabolites are associated with the success of organ transplantation. However, the specific changes in the gut microbiota of lung transplant patients remain unclear. Hence, this study aimed to elucidate the interplay between the gut microbiota, metabolome, and lung transplantation outcomes. Using 16S metagenomics sequencing and untargeted metabolic profiling, we conducted a comprehensive analysis of gut microbial and metabolic alterations in lung transplant recipients relative to non-transplant group. Our findings revealed the predominance of Enterococcus and Streptococcus genera within the lung transplant cohort, accompanied by the significant reduction in Bacteroides, Epulopiscium, Faecalibacterium, and Prevotella abundance. In addition, a significant reduction in ATRA (all-trans retinoic acid) levels and suppression of IgA production were observed in lung transplant recipients, which were found to be closely associated with the Enterococcus genus. It was speculated that the association might have implications for the prognosis of lung transplant patients. Notably, the differences in gut microbial composition and metabolomic profiles between successful transplant recipients and those experiencing chronic rejection were not statistically significant. These novel insights shed light on the putative implications of the gut microbiota and metabolome in shaping lung transplantation outcomes, and provide a foundation for future investigations and targeted therapeutic interventions.

IMPORTANCE

This study has profound implications for lung transplantation as it uncovers the important role of gut microbiota and metabolome in shaping transplantation outcomes. The identification of dominant bacterial genera, such as Enterococcus and Streptococcus, within the lung transplant cohort, along with the significant decrease in Bacteroides, Epulopiscium, Faecalibacterium, and Prevotella abundance, reveals potential microbial imbalances associated with lung transplantation. In addition, a significant reduction in ATRA (all-trans retinoic acid) levels and suppression of IgA production were observed in lung transplant recipients, which were found to be closely associated with the Enterococcus genus. It was speculated that the association might have implications for the prognosis of lung transplant patients. These findings hold immense clinical significance as they lay the groundwork for future research and targeted therapeutic interventions. Understanding the impact of the gut microbiota and metabolome on lung transplantation outcomes offers promising avenues for improving transplantation patient prognosis.

Anxiety and Somatoform Syndromes Predict Transplant-Focused Internet Use in the Course of an Organ Transplantation

Background: e-Health interventions are increasing in the field of organ transplantations; however, the literature lacks evidence regarding needs, attitudes, and preferences of organ recipients and donors during the course of an organ transplantation. Methods: In a cross-sectional study, 70 subjects were assessed using self-rated and validated questionnaires, such as the PRIME MD Patient Health Questionnaire (PHQ-D) and the Essen Resource Inventory (ERI). Group differences and a multiple linear regression were also applied. Results: Organ recipients had significantly higher scores for depression (U = 245.00, z = -2.65, p = 0.008, Cohen's d = 0.32), somatoform (U = 224.50, z = -2.99, p = 0.003, Cohen's d = 0.37), and stress syndromes (U = 266.00, z = -2.25, p = 0.008, Cohen's d = 0.27). They also named the internet and apps as resources to find information regarding organ transplants (U = 177.50, z = -2.07, p = 0.017, Cohen's d = 0.28; Z = -2.308, p = 0.021) and preferred to use apps to monitor the physical condition (Z = -2.12, p = 0.034) significantly more than organ donors. Anxiety and somatoform syndromes were significant predictors to search for information regarding the transplant process (F[6,38] = 3.98, p < 0.001; R2 = 0.386). Conclusions: e-Health interventions are promising in accompanying the course of an organ transplant for patients to be informed and educated. Predominantly, potential organ recipients might benefit from apps to record physical parameters. However, anxiety syndromes might hinder patients from searching for information about the transplant process, while somatoform syndromes might enable patients who are searching for such information.

Knowledge and Attitudes Toward Organ Donation Among Tunisian Adults: Results of a National Survey

OBJECTIVES

Attitudes and knowledge toward organ donation can influence a person's willingness to donate. The aim of this study was to assess attitudes and knowledge regarding organ donation among Tunisian adults.

MATERIALS AND METHODS

We conducted a crosssectional survey at the national level from January 23 to February 15, 2017, among 1026 Tunisian adults. We used a standardized questionnaire to collect data by phone call. We performed statistical analyses with Stata software (version 11).

RESULTS

The study included 495 male and 531 female participants. Forty-one percent of participants were 18 to 30 years old. In total, 81.7% had heard about organ donation. Fewer than half of respondents (47.8%) were aware that organ donation is regulated. In total, 80.7% accepted to donate their organs after death, and 32.2% had mentioned their opinion to relatives or friends. Only 1% had added their donor status on their national identity cards.

CONCLUSIONS

Tunisian adults seem to have positive attitudes regarding organ donation. However, the proportion of respondents who included their donor status on their national identity cards was low. It is important to enhance information and education on organ donation in an effort to mitigate the shortage of organs.

Emerging strategies to bypass transplant rejection via biomaterial-assisted immunoengineering: Insights from islets and beyond

Novel transplantation techniques are currently under development to preserve the function of impaired tissues or organs. While current technologies can enhance the survival of recipients, they have remained elusive to date due to graft rejection by undesired in vivo immune responses despite systemic prescription of immunosuppressants. The need for life-long immunomodulation and serious adverse effects of current medicines, the development of novel biomaterial-based immunoengineering strategies has attracted much attention lately. Immunomodulatory 3D platforms can alter immune responses locally and/or prevent transplant rejection through the protection of the graft from the attack of immune system. These new approaches aim to overcome the complexity of the long-term administration of systemic immunosuppressants, including the risks of infection, cancer incidence, and systemic toxicity. In addition, they can decrease the effective dose of the delivered drugs via direct delivery at the transplantation site. In this review, we comprehensively address the immune rejection mechanisms, followed by recent developments in biomaterial-based immunoengineering strategies to prolong transplant survival. We also compare the efficacy and safety of these new platforms with conventional agents. Finally, challenges and barriers for the clinical translation of the biomaterial-based immunoengineering transplants and prospects are discussed.

Barriers to Organ Donation: A Qualitative Study of Intensive Care Nurses' Experiences

BACKGROUND

An increasing number of patients affected by organ failure can be treated with organ transplantation. The need for organs available for transplantation is critical and patients die while on the transplant list. Intensive care unit (ICU) nurses are essential in facilitating organ donation through their ceaseless bedside care for potential organ donors and their families.

AIMS AND OBJECTIVES

The aim of this study was to describe the challenges faced by ICU nurses in the organ donation process.

DESIGN

A descriptive qualitative study design was used.

METHOD

Semistructured individual interviews of 9 ICU nurses from 1 university hospital were performed. Data were analyzed using Malterud's systematic text condensation.

RESULTS

Three themes describe the core of the results: (1) practical tasks, (2) challenging care for the next of kin, and (3) ethical and emotional challenges.

CONCLUSIONS

Practical tasks represent challenges in the organ donation process that are not previously revealed. Actions to address these challenges should be prioritized to promote organ donation. Simulation-based training may optimize practical aspects of the organ donation process and implementation of simulation-based training should be assessed by future research.

Properties of Poly (Lactic-co-Glycolic Acid) and Progress of Poly (Lactic-co-Glycolic Acid)-Based Biodegradable Materials in Biomedical Research

In recent years, biodegradable polymers have gained the attention of many researchers for their promising applications, especially in drug delivery, due to their good biocompatibility and designable degradation time. Poly (lactic-co-glycolic acid) (PLGA) is a biodegradable functional polymer made from the polymerization of lactic acid (LA) and glycolic acid (GA) and is widely used in pharmaceuticals and medical engineering materials because of its biocompatibility, non-toxicity, and good plasticity. The aim of this review is to illustrate the progress of research on PLGA in biomedical applications, as well as its shortcomings, to provide some assistance for its future research development.

Evaluating the Performance of a Nonelectronic, Versatile Oxygenating Perfusion System across Viscosities Representative of Clinical Perfusion Solutions Used for Organ Preservation

Introduction: On the United States' Organ Transplantation Waitlist, approximately 17 people die each day waiting for an organ. The situation continues to deteriorate as the discrepancy between harvested organs and the number of patients in need is increasing. Static cold storage is the clinical standard method for preserving a harvested organ but is associated with several drawbacks. Machine perfusion of an organ has been shown to improve preservation quality as well as preservation time over static cold storage. While there are machine perfusion devices clinically available, they are costly and limited to specific organs and preservation solutions. This study presents a versatile oxygenating perfusion system (VOPS) that supplies oxygen and pulsatile perfusion. Materials and Methods: Experiments evaluated the system's performance with a human kidney mimicking hydraulic analog using multiple compressed oxygen supply pressures and aqueous solutions with viscosities ranging from 1 to 6.5 cP, which simulated viscosities of commonly used organ preservation solutions. Results and Conclusions: The VOPS produced mean flow rates ranging from 0.6 to 28.2 mL/min and perfusion pressures from 4.8 to 96.8 mmHg, which successfully achieved the desired perfusion parameters for human kidneys. This work provides evidence that the VOPS described herein has the versatility to perfuse organs using many of the clinically available preservation solutions.

Foxp3+ regulatory T cell therapy for tolerance in autoimmunity and solid organ transplantation

Regulatory T cells (Tregs) are critical for tolerance in humans. The exact mechanisms by which the loss of peripheral tolerance leads to the development of autoimmunity and the specific role Tregs play in allograft tolerance are not fully understood; however, this population of T cells presents a unique opportunity in the development of targeted therapeutics. In this review, we discuss the potential roles of Foxp3+ Tregs in the development of tolerance in transplantation and autoimmunity, and the available data regarding their use as a treatment modality.

Classic and Current Opinions in Human Organ and Tissue Transplantation

Graft tolerance is a pathophysiological condition heavily reliant on the dynamic interaction of the innate and adaptive immune systems. Genetic polymorphism determines immune responses to tissue/organ transplantation, and intricate humoral and cell-mediated mechanisms control these responses. In transplantation, the clinician's goal is to achieve a delicate equilibrium between the allogeneic immune response, undesired effects of the immunosuppressive drugs, and the existing morbidities that are potentially life-threatening. Transplant immunopathology involves sensitization, effector, and apoptosis phases which recruit and engages immunological cells like natural killer cells, lymphocytes, neutrophils, and monocytes. Similarly, these cells are involved in the transfer of normal or genetically engineered T cells. Advances in tissue transplantation would involve a profound knowledge of the molecular mechanisms that underpin the respective immunopathology involved and the design of precision medicines that are safe and effective.

Patient-reported outcomes evaluation and assessment of facilitators and barriers to physical activity in the Transplantoux aerobic exercise intervention

Background

Transplantoux’s MVT exercise intervention prepares organ transplant recipients to cycle or hike up France’s Mont Ventoux. We aimed to assess (i) MVT’s effects on patient-reported outcomes (PROs) and (ii) perceived barriers and facilitators to physical activity.

Methods

Using a hybrid design, a convenience sample of transplant recipients participating in MVT (n = 47 cycling (TxCYC); n = 18 hiking (TxHIK)), matched control transplant recipients (TxCON, n = 213), and healthy MVT participants (HCON, n = 91) completed surveys to assess physical activity (IPAQ), health-related quality of life (HRQOL; SF-36 and EuroQol VAS), mental health (GHQ-12), and depressive symptomatology, anxiety, and stress (DASS-21) at baseline, then after 3, 6 (Mont Ventoux climb), 9, and 12 months. TxCYC and TxHIK participated in a 6-month intervention of individualized home-based cycling/hiking exercise and a series of supervised group training sessions. Barriers and facilitators to physical activity (Barriers and Motivators Questionnaire) were measured at 12 months.

Results

Regarding PROs, except for reducing TxHIK stress levels, MVT induced no substantial intervention effects. For both TxCYC and TxHIK, between-group comparisons at baseline showed that physical activity, HRQOL, mental health, depressive symptomatology and stress were similar to those of HCON. In contrast, compared to TxCYC, TxHIK, and HCON, physical activity, HRQOL and mental health were lower in TxCON. TxCON also reported greater barriers, lower facilitators, and different priority rankings concerning physical activity barriers and facilitators.

Conclusion

Barely any of the PROs assessed in the present study responded to Transplantoux’s MVT exercise intervention. TxCON reported distinct and unfavorable profiles regarding PROs and barriers and facilitators to physical activity. These findings can assist tailored physical activity intervention development.

Trial registration

Clinical trial notation: The study was approved by the University Hospitals Leuven’s Institutional Review Board (B322201523602).

Immune response associated with ischemia and reperfusion injury during organ transplantation

Background

Ischemia and reperfusion injury (IRI) is an ineluctable immune-related pathophysiological process during organ transplantation, which not only causes a shortage of donor organs, but also has long-term and short-term negative consequences on patients. Severe IRI-induced cell death leads to the release of endogenous substances, which bind specifically to receptors on immune cells to initiate an immune response. Although innate and adaptive immunity have been discovered to play essential roles in IRI in the context of organ transplantation, the pathway and precise involvement of the immune response at various stages has not yet to be elucidated.

Methods

We combined “IRI” and “organ transplantation” with keywords, respectively such as immune cells, danger signal molecules, macrophages, neutrophils, natural killer cells, complement cascade, T cells or B cells in PubMed and the Web of Science to search for relevant literatures.

Conclusion

Comprehension of the immune mechanisms involved in organ transplantation is promising for the treatment of IRI, this review summarizes the similarities and differences in both innate and adaptive immunity and advancements in the immune response associated with IRI during diverse organ transplantation.

Location of organ procurement and distribution organisation decisions and their impact on kidney allocations: a developing country perspective

Managing organ transplant networks is a complex task. It intertwines between locating the organ procurement and distribution organization (OPDO) (long-term decision) and allocating organs to the suitable destination (short-term decision). The literature lacks deliberation on the effect of those long-term decisions on short-term ones under the influence of clinical and non-clinical factors. This paper addresses this gap using a k-sum model for locational choice, and a discrete simulation approach for the allocation procedure for a real-life case study from a developing economy perspective. The study explores the trade-off between efficiency (distance-centric models) and equity (the result of time-centric allocation models). Our analysis of the efficiency of locational models and equity of the allocation policies reveal strong inter-dependence of both these decisions, a significant finding of this research. These findings offer an integrated model for high-level decision-makers, which can be used during the locational planning stage and provide input to design standard operating procedures for transplantation schemes.

Deceased Donor Characteristics and Kidney Transplant Outcomes

Kidney transplantation is the therapy of choice for people living with kidney failure who are suitable for surgery. However, the disparity between supply versus demand for organs means many either die or are removed from the waiting-list before receiving a kidney allograft. Reducing unnecessary discard of deceased donor kidneys is important to maximize utilization of a scarce and valuable resource but requires nuanced decision-making. Accepting kidneys from deceased donors with heterogenous characteristics for waitlisted kidney transplant candidates, often in the context of time-pressured decision-making, requires an understanding of the association between donor characteristics and kidney transplant outcomes. Deceased donor clinical factors can impact patient and/or kidney allograft survival but risk-versus-benefit deliberation must be balanced against the morbidity and mortality associated with remaining on the waiting-list. In this article, the association between deceased kidney donor characteristics and post kidney transplant outcomes for the recipient are reviewed. While translating this evidence to individual kidney transplant candidates is a challenge, emerging strategies to improve this process will be discussed. Fundamentally, tools and guidelines to inform decision-making when considering deceased donor kidney offers will be valuable to both professionals and patients.

Management of Atopic Dermatitis: The Role of Tacrolimus

Atopic dermatitis (AD) is a long-lasting inflammatory dermatological condition characterized by itchy, eczematous, sparsely tiny blisters that hold a clear watery substance. Additionally, the diseased skin can suppurate, occasionally with weeping with thickening of the affected skin. This is considered one of the top skin disorders involving both children and adult populations globally. The principal therapeutic intervention for AD is long-standing topical glucocorticoids, which have been used for several decades. Corticosteroid therapy brings several adverse drug effects (ADRs), including irreversible skin atrophy. Tacrolimus belongs to the class of calcineurin inhibitors, which is a type of immunomodulator possessing promising efficacy in treating AD. Topical tacrolimus is an effective and safe non-corticosteroid substitute treatment for AD. We reviewed the available literature to compare and institute the safety, efficacy, and effectiveness of tacrolimus when equated to corticosteroid therapy in managing AD.

Adhesive anastomosis for organ transplantation

The recent development of tough tissue adhesives has stimulated intense interests among material scientists and medical doctors. However, these adhesives have seldom been tested in clinically demanding surgeries. Here we demonstrate adhesive anastomosis in organ transplantation. Anastomosis is commonly conducted by dense sutures and takes a long time, during which all the vessels are occluded. Prolonged occlusion may damage organs and even cause death. We formulate a tough, biocompatible, bioabsorbable adhesive that can sustain tissue tension and pressurized flow. We expose the endothelial surface of vessels onto a gasket, press two endothelial surfaces to the adhesive using a pair of magnetic rings, and reopen the bloodstream immediately. The time for adhesive anastomosis is shortened compared to the time for sutured anastomosis. We have achieved adhesive anastomosis of a great vein in transplanting the liver of a pig. After the surgery, the adhesive is absorbed, the vein heals, and the pig lives for over one month.

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Use tough hydrogel to achieve adhesive anastomosis of a great vein in porcine liver transplantation.

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The time for adhesive anastomosis is shortened compared to the time for sutured anastomosis.

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The tough hydrogel can be bioabsorbed and enable the vessel to heal.

Living donor kidney paired exchange: An observational study

Background

Kidney transplantation is the treatment of choice for patients with end-stage renal disease (ESKD). Kidney paired donation (KPD) provides the chance to match an incompatible donor/recipient pair with another donor and recipient in a similar condition. We aimed to compare the outcomes of pair exchange kidney transplantation with traditional live donor kidney transplantation in our context.

Method

A review of medical records of 62 patients (31 pairs) who underwent two-way conventional living kidney pair exchange from July 2016 to June 2021 was done. The control group was considered those 62 patients who had undergone classic live donor kidney transplantation (LDKT) during the study period. The patient's demographics, intraoperative and postoperative variables including delayed graft function, length of hospital stay, graft survival, patient survival, and rejections rates were compared between the groups (KPD and LDKT).

Results

The majority of recipients were male (77.4 and 80.6%) while donors were female (77.4 and 69.4%) in KPD and the LDKT groups. Mean ages were 37 years (range: 19–59) and 37 years (range: 17–65) for the recipient's in KPD and the LDKT. KPD transplantation was performed in 62 recipients to avoid blood group incompatibility. There were no significant differences in outcomes comprising delayed graft function (1.6 and 3.2%), graft survival (100% in both groups), patient survival (95.2 and 96.8%), and rejections rates (1.6 and 1.6%) between KPD and LDKT group (P > 0.005). The length of stay was similar (5.9 and 5.7 days) in KPD and LDKT groups (P > 0.005).

Conclusions

The outcomes of KPD were comparable with classic LDKT in terms of delayed graft function, length of hospital stay, graft survival, patient survival, and rejections rates in our study. Therefore, the kidney paired donation program should be encouraged and promoted in centers where the ABO-incompatible transplant is expensive with added risk and the rate of deceased donor transplantation is very low.

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Kidney paired donation (KPD) provides the chance to match for an incompatible donor/recipient pair with another donor and recipient in a similar condition.

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The outcomes of KPD were comparable with classic live donor kidney transplantation (LDKT) in this study.

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KPD program should be promoted in centers where the ABO incompatible transplant is expensive with added risk and the rate of deceased donor transplantation is very low.

Impact of novel microbial secondary metabolites on the pharma industry

Abstract

Microorganisms are remarkable producers of a wide diversity of natural products that significantly improve human health and well-being. Currently, these natural products comprise half of all the pharmaceuticals on the market. After the discovery of penicillin by Alexander Fleming 85 years ago, the search for and study of antibiotics began to gain relevance as drugs. Since then, antibiotics have played a valuable role in treating infectious diseases and have saved many human lives. New molecules with anticancer, hypocholesterolemic, and immunosuppressive activity have now been introduced to treat other relevant diseases. Smaller biotechnology companies and academic laboratories generate novel antibiotics and other secondary metabolites that big pharmaceutical companies no longer develop. The purpose of this review is to illustrate some of the recent developments and to show the potential that some modern technologies like metagenomics and genome mining offer for the discovery and development of new molecules, with different functions like therapeutic alternatives needed to overcome current severe problems, such as the SARS-CoV-2 pandemic, antibiotic resistance, and other emerging diseases.

Key points

• Novel alternatives for the treatment of infections caused by bacteria, fungi, and viruses.

• Second wave of efforts of microbial origin against SARS-CoV-2 and related variants.

• Microbial drugs used in clinical practice as hypocholesterolemic agents, immunosuppressants, and anticancer therapy.

A New Generation of Cell Therapies Employing Regulatory T Cells (Treg) to Induce Immune Tolerance in Pediatric Transplantation

Kidney transplantation is the most common solid organ transplant and the preferred treatment for pediatric patients with end-stage renal disease, but it is still not a definitive solution due to immune graft rejection. Regulatory T cells (Treg) and their control over effector T cells is a crucial and intrinsic tolerance mechanism in limiting excessive immune responses. In the case of transplants, Treg are important for the survival of the transplanted organ, and their dysregulation could increase the risk of rejection in transplanted children. Chronic immunosuppression to prevent rejection, for which Treg are especially sensitive, have a detrimental effect on Treg counts, decreasing the Treg/T-effector balance. Cell therapy with Treg cells is a promising approach to restore this imbalance, promoting tolerance and thus increasing graft survival. However, the strategies used to date that employ peripheral blood as a Treg source have shown limited efficacy. Moreover, it is not possible to use this approach in pediatric patients due to the limited volume of blood that can be extracted from children. Here, we outline our innovative strategy that employs the thymus removed during pediatric cardiac surgeries as a source of therapeutic Treg that could make this therapy accessible to transplanted children. The advantageous properties and the massive amount of Treg cells obtained from pediatric thymic tissue (thyTreg) opens a new possibility for Treg therapies to prevent rejection in pediatric kidney transplants. We are recruiting patients in a clinical trial to prevent rejection in heart-transplanted children through the infusion of autologous thyTreg cells (NCT04924491). If its efficacy is confirmed, thyTreg therapy may establish a new paradigm in preventing organ rejection in pediatric transplants, and their allogeneic use would extend its application to other solid organ transplantation.

Biological Predictors of De Novo Tumors in Solid Organ Transplanted Patients During Oncological Surveillance: Potential Role of Circulating TERT mRNA

Background

De novo tumors are a major cause of morbidity and mortality after long-term solid organ transplantation. Chronic immunosuppression strongly affects solid organ transplanted (SOT) patients' immune system by promoting immune evasion strategies and reactivations of viruses with oncogenic potential, ultimately leading to cancer onset. In this scenario, an oncological Surveillance Protocol integrated with biobanking of peripheral blood samples and evaluation of immunovirological and molecular parameters was activated for SOT patients at CRO-IRCCS Aviano, with the aim of identifying suitable biomarkers of cancer development.

Methods

An exploratory longitudinal study was designed based on two serial peripheral blood samples collected at least three months apart. Forty nine SOT patients were selected and stratified by tumor onset during follow-up. Spontaneous T-cell responses to EBV, CMV and tumor associated antigens, EBV-DNA and CMV-DNA loads, and circulating TERT mRNA levels were investigated.

Results

Significantly higher levels of circulating TERT mRNA were observed 3.5-23.5 months before and close to the diagnosis of cancer as compared to tumor-free patients. Plasmatic TERT mRNA levels >97.73 copies/mL at baseline were significantly associated with the risk of developing de novo tumors (HR=4.0, 95%C.I. = 1.4-11.5, p=0.01). In particular, the risk significantly increased by 4% with every ten-unit increment in TERT mRNA (HR=1.04, 95%C.I. = 1.01-1.07, p=0.01).

Conclusions

Although obtained in an exploratory study, our data support the importance of identifying early biomarkers of tumor onset in SOT patients useful to modulate the pace of surveillance visits.

T-cell Immunometabolism: Therapeutic Implications in Organ Transplantation

Although solid-organ transplantation has evolved steadily with many breakthroughs in the past 110 y, many problems remain to be addressed, and advanced therapeutic strategies need to be considered. T-cell immunometabolism is a rapidly advancing field that has gathered much attention recently, providing ample mechanistic insight from which many novel therapeutic approaches have been developed. Applications from the field include antitumor and antimicrobial therapies, as well as for reversing graft-versus-host disease and autoimmune diseases. However, the immunometabolism of T cells remains underexplored in solid-organ transplantation. In this review, we will highlight key findings from hallmark studies centered around various metabolic modes preferred by different T-cell subtypes (categorized into naive, effector, regulatory, and memory T cells), including glycolysis, glutaminolysis, oxidative phosphorylation, fatty acid synthesis, and oxidation. This review will discuss the underlying cellular signaling components that affect these processes, including the transcription factors myelocytomatosis oncogene, hypoxia-inducible factor 1-alpha, estrogen-related receptor alpha, and sterol regulatory element-binding proteins, along with the mechanistic target of rapamycin and adenosine monophosphate-activated protein kinase signaling. We will also explore potential therapeutic strategies targeting these pathways, as applied to the potential for tolerance induction in solid-organ transplantation.

The effect of immunosuppressive therapy after liver transplantation on activities of daily living and fear of death during the COVID-19 pandemic

BACKGROUND

In our study, we aimed to investigate the effect of immunosuppressive therapy after liver transplantation on activities of daily living and fear of death during the COVID-19 pandemic.

METHODS

This study was conducted as a cross-sectional study with the participation of 213 liver transplant patients hospitalized in the liver transplant center of a university hospital. The data analysis was performed with IBM SPSS (Statistical Package for the Social Sciences) Statistics 25.

RESULTS

Katz's Activities of Daily Living (ADL) were semi-independent and the total score was 11.07 ± 1.59, and the Death Attitude Profile-Revised (DAP-R) total score was 152.23 ± 5.34. It was determined that the DAP-R score was around 150 points in the minimum and maximum score ranges of Katz ADL after liver transplantation.

CONCLUSIONS

High fear of death threatens resilience and can make patients feel lonely, helpless, sad, abandoned and stressed. Clinicians should spend more time with their patients.

An overview of the efficacy and safety of everolimus in adult solid organ transplant recipients

As the risk of graft loss due to acute rejection has declined, the goal of post-transplant management has switched to long-term preservation of organ function. Minimizing calcineurin inhibitor (CNI)-related nephrotoxicity is a key component of this objective. Everolimus is a mammalian target of rapamycin inhibitor/proliferation-signal inhibitor with potent immunosuppressive and anti-proliferative effects. It has been widely investigated in large randomized clinical studies that have shown it to have similar anti-rejection efficacy compared with standard-of-care regimens across organ transplant indications. With demonstrated potential to facilitate the reduction of CNI therapy and preserve renal function, everolimus is an alternative to the current standard-of-care CNI-based regimens used in de novo and maintenance solid organ transplantation recipients. Here, we provide an overview of the evidence from the everolimus clinical study program across kidney, liver, heart, and lung transplants, as well as other key data associated with its use in CNI reduction strategies in adult transplant recipients.

Anti-angiogenic activity of azathioprine

Azathioprine (AZA) is the main drug used in immunomodulatory therapy in post-transplant patients or with autoimmune diseases. However, no study has evaluated the AZA angiogenic response. Therefore, this study investigated the effects of AZA on the angiogenic process through macroscopic, histological, and immunohistochemical analyses in chick embryo chorioallantoic membrane (CAM). Our results showed potent anti-angiogenic activity of AZA at the higher concentrations tested in the CAM assay. The histological analysis of CAM confirmed this effect, since AZA induced a significant reduction in all parameters evaluated. In addition, immunohistochemical evaluation of CAM revealed that AZA decreased TGF-β and VEGF levels, important cytokines involved in the angiogenic process. Therefore, the AZA anti-angiogenic effect identified in our study provides new information for the possible application of this drug in anticancer treatment.

Malignancy among adult heart transplant recipients following patient-tailored dosing of anti-thymocyte globulin: a retrospective, nested case-control study of individualized dosing

Post-transplant malignancy is diagnosed in approximately 18% of heart transplant patients and is a leading cause of death post-transplant. One modifiable risk factor is the type and amount of immunosuppression received. Contemporary rabbit anti-thymocyte globulin (rATG) dosing strategy using T-cell-guided dosing, and its effect on malignancy in heart transplant patients is unclear. This was a single-center, retrospective chart review of heart transplant recipients receiving rATG for induction. Patients diagnosed with malignancy post-transplant were matched 1:2 to controls using a nested case-control design. The primary endpoint was to determine the relative risk of rATG exposure with the actual incidence of malignancy post-transplant. The secondary endpoint was the impact of maintenance immunosuppression on malignancy risk. Of the 126 patients included in the study, 25 developed malignancy and were matched to 50 control patients. The median cumulative rATG dose in milligrams (mg) between groups was 365 mg in malignancy cases and 480 mg in controls (OR 0.90, 95% CI 0.75-1.08, P = 0.28). In both the univariate and multivariable analysis, there was no statistically significant difference in malignancy risk found with any maintenance immunosuppressant. The results of this study showed that patient-tailored rATG dosing strategies may not be associated with malignancy development as previously thought.

Comparison between slow and rapid freezing for adrenal gland cryopreservation and xenotransplantation

The aim of our study was to examine whether slow or rapid cryopreservation of adrenal xenografts affected xenotransplant outcome. Adrenal xenografts were got from newborn piglets (<24 h after birth). Receptor rats were randomly divided into four groups: a bilateral adrenalectomy group, fresh xenotransplantation group, rapid cryopreservation xenotransplantation group, and a slow cryopreservation xenotransplantation group. 30 days after xenotransplantation, the survival rates of rats in the fresh xenotransplantation group, rapid cryopreservation xenotransplantation group and slow cryopreservation xenotransplantation group were 80 %, 60 % and 60 %, respectively, which were significantly higher than 40 % of the bilateral adrenalectomy group. In addition, the survival rate of rats in the slow cryopreservation group was consistently significantly higher than that in the rapid cryopreservation group at 29 days after xenotransplantation. Morphological observation showed that there were a few medulla cells existed in the adrenal glands in the slow cryopreservation group after 30 days of xenotransplantation, but no medulla cells were found in the rapid cryopreservation group. The plasma cortisol level of rats in the fresh xenotransplantation group and the slow xenotransplantation group 30 days after xenotransplantation was significantly higher than that of the rapid cryopreservation group and bilateral adrenalectomy group (P < 0.05). The levels of liver glycogen and cholesterol in the xenotransplantation rats were increased relative to those of the bilateral adrenalectomy rats, and close to normal level. In conclusion, compared with rapidly frozen preserved grafts, slowly frozen preserved grafts not only ensure the structural integrity of adrenal tissues, but also have corresponding physiological functions, which provid a basic research opportunities for the preservation of xenografts and the treatment of adrenal corticosteroid deficiency. Moreover, these findings can provide evidence for xenotransplantation in the treatment of Addison's disease (adrenal cortex hormone deficiency).

Depression, anxiety, and associated psychological outcomes in living organ transplant donors: A systematic review

With increasing demands for living organ donations, understanding the prevalence of depression and anxiety, which are the commonest psychiatric disorders in donors following organ transplantation, will serve to improve psychiatric care to safeguard donors' mental wellbeing. This descriptive systematic review examines all observational studies in English investigating prevalence of depression and anxiety in adult transplant donors using bibliographic databases. Sixty-two papers were included (kidney, n = 25; liver, n = 25; bone marrow, n = 7; uterus, n = 2; lung, n = 1; kidney and lung concurrently, n = 2). Post-transplantation depression and anxiety prevalence rates (Depression: 0-46.9%, Anxiety: 0-66.7%) did not differ significantly from pre-transplantation and were largely comparable to the general population. Other psychiatric disorders observed included bipolar disorder, conversion disorder, adjustment disorder and sleep disorder. Other psychological outcomes observed included lower quality of life, lower satisfaction of life and regret after donation. Pre-donation risk factors such as poor physical/psychological health status, and post-donation risk factors such as complicated post-surgical recovery and poor physical/psychological health in recipients were identified, predisposing donors to poor psychological outcomes. Individuals with risk factors should be monitored and provided with social support, psychoeducation, psychotherapy and long-term follow up. Future studies should adopt consistent methodological approaches to improve comparability between various studies. More research investigating poor psychological outcomes in other organ donors besides kidney and liver donors, donors who have past psychiatric history, unrelated and parent donors is warranted.

Recombinogenic, genotoxic, and cytotoxic effects of azathioprine using in vivo assays

Azathioprine (Aza) is a purine antimetabolite immunosuppressant that is widely employed for immunosuppressive therapy in post-transplant recipients or patients with autoimmune diseases. Chronic use of immunosuppressants might produce several side effects, including a high rate of neoplasms in these patients. Considering that genotoxic effects are associated with an increased risk of developing cancer, the aim of this study was to examine the recombinogenic, genotoxic, and cytotoxic effects of Aza using Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster, as well as comet and micronucleus assays in mouse bone marrow cells. Further, the adverse effects of Aza were determined in mouse hepatic and renal tissues using histopathological analysis. Data demonstrated that Aza induced significant increased genotoxicity in D. melanogaster and mouse bone marrow cells at all concentrations tested. Homologous recombination was the predominant genotoxic event noted for the first time to be initiated by Aza in SMART. In histopathological analysis, Aza did not show any marked toxic activity in mouse hepatic and renal tissues. Therefore, the high rate of neoplasms reported in patients with long-term use of Aza may be attributed, at least partially, to the genotoxic action of this drug.

Adoptive Transfer of Regulatory Immune Cells in Organ Transplantation

Chronic graft rejection remains a significant barrier to solid organ transplantation as a treatment for end-organ failure. Patients receiving organ transplants typically require systemic immunosuppression in the form of pharmacological immunosuppressants for the duration of their lives, leaving these patients vulnerable to opportunistic infections, malignancies, and other use-restricting side-effects. In recent years, a substantial amount of research has focused on the use of cell-based therapies for the induction of graft tolerance. Inducing or adoptively transferring regulatory cell types, including regulatory T cells, myeloid-derived suppressor cells, and IL-10 secreting B cells, has the potential to produce graft-specific tolerance in transplant recipients. Significant progress has been made in the optimization of these cell-based therapeutic strategies as our understanding of their underlying mechanisms increases and new immunoengineering technologies become more widely available. Still, many questions remain to be answered regarding optimal cell types to use, appropriate dosage and timing, and adjuvant therapies. In this review, we summarize what is known about the cellular mechanisms that underly the current cell-based therapies being developed for the prevention of allograft rejection, the different strategies being explored to optimize these therapies, and all of the completed and ongoing clinical trials involving these therapies.

Prednisone is genotoxic in mice and Drosophila melanogaster

Prednisone (PD) is one of the most commonly used corticosteroids in immunosuppressive therapy for patients with autoimmune diseases and transplants. Chronic use of corticosteroids is associated with several side effects and an increase in neoplasia. Since genotoxic effects are associated with an increased risk of cancer development, this study evaluated the genotoxic and cytotoxic activities of PD using the SMART/wing assay in Drosophila melanogaster and the micronucleus test and comet assay in mouse bone marrow cells. Further, the toxic effects of PD on mouse organ tissues were assessed using histopathological analyses. In the SMART/wing assay, PD showed a significant genotoxic activity at all concentrations tested (0.375, 0.75, 1.5, and 2.0 mg/mL) compared to the negative control (p < 0.05). The micronucleus test and comet assay also showed an elevated genotoxicity of PD at all treatment conditions (24, 48, and 120 h with doses ranging from 0.5 to 1.5 mg/kg) compared to the negative control (p < 0.05). The histopathological analyses did not show toxicity of PD in mouse cells and tissues. Therefore, our results demonstrate that PD is a potent genotoxic immunosuppressant in mice and D. melanogaster cells. Somatic recombination was the primary contributor (46%-82%) to the induced genotoxicity observed in the SMART test.

Optimal management of brain-dead organ donor

Maintaining a brain stem-dead (BSD) donor is specialized science. It is a daunting task as they are fragile patients who need to be handled with utmost care owing to extreme haemodynamically instability and need the best of monitoring for maintenance of organs. To ensure a successful transplant, a BSD donor first needs to be identified on time. This requires scrupulous monitoring of neurologically compromised patients who tend to be the most frequent organ donors. Once the donor is identified, an all-out effort should be made to legally obtain consent for the donation. This may require numerous sessions of counselling of the relatives. It needs to be performed tactfully, displaying the best of intentions. It is important to understand the physiology of a brain-dead individual. A cascade of changes occurs in BSD donor which result in a catastrophic plummeting of the clinical condition of the donor. All organ systems are involved in this clinical chaos, and best possible clinical support of all organ systems should be available and extended to the donor. Organ support includes cardiovascular, pulmonary, temperature, glycaemic, metabolic and hormonal. This article has been written as a follow-up article of previously published article on identifying an organ donor. It intends to give the reader a concept of what the BSD donor undergoes after brain death and as to how to maintain and preserve various organs for donation for successful transplantation of maximum organs.

Exploring new frontiers: Organ transplant anaesthesia or bariatric anaesthesia

Unlike previous years, Anaesthesiology today is a major speciality encompassing many areas of modern medicine. Advent of various surgical sub-specialities resulted into the emergence of anaesthesia sub-specialities, as every group of surgery has specific need. Choosing the best-suited speciality is a complex matter. For that, one needs to have an idea about each one of them. A postgraduate anaesthesiology student does not have adequate exposure to choose the speciality. This article will give an overview of two important sub-specialities i.e., Organ Transplant Anaesthesia and Bariatric Anaesthesia.

Experiences of Families Following Organ Donation Consent: A Qualitative Systematic Review

OBJECTIVE

This systematic review synthesizes qualitative evidence on the experiences of donor families after consent to organ donation.

METHODS

This robust, qualitative systematic review included an exhaustive search of electronic databases, including PubMed, Scopus, EBSCO PsycINFO, and CINAHL Complete. Manual searches of reference lists and gray literature were conducted to achieve a comprehensive identification of all relevant research. A qualitative study design served to capture the experiences of donor families after organ donation consent.

RESULTS

A total of 6 articles that met the eligibility criteria were identified and included in this review. Three key themes emerged from the primary research: 1. family members were ambivalent about consent due to the ambiguity of brain death; 2. conversations about donation requirements proved uncomfortable; and 3. support is needed after donation.

CONCLUSIONS

Family members demonstrated ongoing ambivalence and distress that lasted for weeks after organ donation due to the ambiguity of brain death. Some family members were unhappy with having been approached for a conversation about organ donation. Donor families were not always able to deal with the difficulties they faced after their decision about organ donation. Health care professionals should provide ongoing care and updated information to family members. This review helped to identify family members' needs for both psychological and financial assistance.

Knowledge and Attitudes about Organ Donation among Patient Companion at a Tertiary Hopsital in Ethiopia

BACKGROUND

Worldwide, the supply of organs continues to be much less than the demand. Many studies identify poor knowledge and negative attitude about organ donation for this. The purpose of this study was to assess knowledge and attitude towards organ donation and associated factors among people who accompany patient during hospital visit at tertiary hospital in Ethiopia.

METHODS

A hospital-based cross-sectional study was conducted from March 1st to May 31, 2019, at a tertiary hospital and the only transplant center in Ethiopia. The patient companions were interviewed with structured questionnaires. Descriptive statistics were presented and factors associated with good knowledge and favorable attitude were assessed using Binary logistic regression.

RESULTS

A total of 414 patient companion participated in the study. The mean age of the respondents was 35±13years, and 252(60.9%) were males. Forty-four (10.6%) of the study participants had good knowledge about organ donation. Male gender was significantly associated with improved knowledge (AOR=2.127 95% CI: 1.036, 4.368). A favorable attitude towards donation was found in 219(52.9%) of the study participants. Participants who had completed secondary education were more likely to have unfavorable attitude towards organ donation (AOR =0.498, 95% CI: 0.290, 0.857).

CONCLUSION

Knowledge about organ donation was found to be poor, and attitudes towards organ donation were found to be unfavorable among patient companions at a major medical center in Ethiopia. Strategies focused on education of the general public and broad dissemination of information on the benefits of organ donation will be critical for improving the organ donor pool.

Social representations and interface layout: A new way of enhancing persuasive technology applied to organ donation

Although campaigns promoting organ donation have proved their effectiveness, increasing the number of people who explicitly agree to become donors is still difficult. Based on the social marketing notion of persuasive technology, we reasoned that it was timely to focus on the design of this persuasive technology and to analyze its contribution in particularly challenging contexts such as organ donation. More specifically, the originality of the present study lay in the way we linked the field of persuasive technology to the theory of social representations, and combined them with an analysis of the ergonomic aspects of interface layout. This study had two complementary goals. The first was to determine whether the sociocognitive salience of the central elements of social representations (i.e., the most frequent and important themes related to the subject-here, organ donation-for individuals), can be used to achieve persuasive outcomes. The second was to determine whether interface layout, in terms of information location and background characteristics (color and contrast), can strengthen the persuasive impact. University students (N > 200) were exposed to a computer screen displaying a message involving either central or peripheral elements of the social representations of organ donation (status), placed either in the middle or on one side of the screen (location), and shown against either a white or a blue background (background). Eye-tracking data were recorded, in addition to self-reported data. In line with the elaboration likelihood model, results showed that participants who were exposed to central (vs. peripheral) elements of the social representations of organ donation followed the central route in processing information. Moreover, they had stronger attitudes, and more of them stated that they were actual organ donors. Importantly, however, at least for some variables, these status-related effects were not independent of the interface layout. More specifically, the persuasive impact of the central elements was enhanced when the information was displayed in the middle (vs. the side) of the screen and when it was displayed on a white (vs. blue) background. We discuss the theoretical and practical issues raised by these results.

Plasma Acute Phase Proteins as Predictors of Chronic Lung Allograft Dysfunction in Lung Transplant Recipients

Cumulating reports suggest that acute phase proteins (APPs) have diagnostic and prognostic value in different clinical conditions. Among others, APPs are proposed to serve as markers that help to control the outcome of transplant recipients. Here, we questioned whether plasma concentrations of APPs mirror the development of chronic lung allograft dysfunction (CLAD). We performed blinded analysis of serial plasma samples retrospectively collected from 35 lung transplanted patients, of whom 25 developed CLAD and 10 remained stable during the follow-up period of 3 to 4.5 years. Albumin (ALB), alpha1-antitrypsin (AAT), high sensitivity C-reactive protein (CRPH), antithrombin-3 (AT3), ceruloplasmin (CER), and alpha2-macroglobulin (A2MG) were measured by the nephelometric method. We found that within the first six months post-transplantation, levels of A2MG, CER and AAT were higher in stable patients relative to those who later developed CLAD. Moreover, in stable patient’s plasma CRPH levels decreased during the follow-up period whereas opposite, in those developing CLAD, the CRPH gradually increased. The ALB levels became significantly lower at the end of the follow-up period in CLAD relative to a stable group. A logistic regression model based on A2MG, CER and AT3 at cut-offs levels of ≥175.5 mg/dL, ≥37.8 mg/dL and ≥27.35 mg/dL enabled to discriminate between stable and CLAD patients with a sensitivity of 87.5%, 100% and 62.5%, and specificity of 65.9%, 72.7% and 79.5%, respectively. We identified A2MG (below 175.5 mg/dL) as an independent predictor of CLAD (hazard ratio 11.5, 95% CI (1.5–91.3), p<0.021). Our findings suggest that profiles of certain APPs may help to predict the development of lung dysfunction at the very early stages after transplantation.

Comparison of Standard and Modified Standard Organ Procurement Techniques for Deceased Donors

OBJECTIVES

This study aimed to compare the impact of deceased-donor organ procurement techniques (standard versus modified standard) on biochemical outcomes after liver transplant.

MATERIALS AND METHODS

From February 2006 to December 2013, organs were recovered from 105 consecutive deceased donors by our transplant team. All organ procurement procedures were performed by a pioneer surgeon experienced in organ recovery from deceased donors. Donors were divided into those who had the abdominothoracic approach, which is referred to as the standard technique, and those who had the abdominal approach, which is referred to as the modified standard technique. Both groups were compared in terms of age, sex, weight, height, body mass index, liver graft weight, cross-clamping time, cold ischemia time, and liver function tests in recipients over the first 3 postoperative days.

RESULTS

Our study group included 66 male and 39 female donors, with an age range of 1 to 93 years (median of 44 y, means ± standard deviation of 43.8 ± 23.7 y). Among the deceased donors, 73 underwent the modified standard technique and 32 underwent the standard technique. There were no statistically significant differences between groups in terms of age, sex, weight, height, body mass index, graft weight, cold ischemia time, and liver function tests in recipients over the first 3 postoperative days. We observed a statistically significant difference between groups in terms of cross-clamping time (P < .001).

CONCLUSIONS

Except for the decreased cross-clamping time, the modified standard technique for deceased organ retrieval had no effect on clinical outcomes in recipients after liver transplant. However, this retrospective study requires additional prospective investigations to more fully understand the differences.

A Versatile Open-Source Printhead for Low-Cost 3D Microextrusion-Based Bioprinting

Three-dimensional (3D) bioprinting promises to be essential in tissue engineering for solving the rising demand for organs and tissues. Some bioprinters are commercially available, but their impact on the field of Tissue engineering (TE) is still limited due to their cost or difficulty to tune. Herein, we present a low-cost easy-to-build printhead for microextrusion-based bioprinting (MEBB) that can be installed in many desktop 3D printers to transform them into 3D bioprinters. We can extrude bioinks with precise control of print temperature between 2-60 °C. We validated the versatility of the printhead, by assembling it in three low-cost open-source desktop 3D printers. Multiple units of the printhead can also be easily put together in a single printer carriage for building a multi-material 3D bioprinter. Print resolution was evaluated by creating representative calibration models at different temperatures using natural hydrogels such as gelatin and alginate, and synthetic ones like poloxamer. Using one of the three modified low-cost 3D printers, we successfully printed cell-laden lattice constructs with cell viabilities higher than 90% after 24-h post printing. Controlling temperature and pressure according to the rheological properties of the bioinks was essential in achieving optimal printability and great cell viability. The cost per unit of our device, which can be used with syringes of different volume, is less expensive than any other commercially available product. These data demonstrate an affordable open-source printhead with the potential to become a reliable alternative to commercial bioprinters for any laboratory.

Nanotechnology Applications in Transplantation Medicine

A recent technological advance that shows promise for applications in health care, including transplantation medicine, is the implementation of nanoparticles. Nanoparticles can be composed of a variety of organic or inorganic materials and confer many advantages over conventional treatments available, such as low toxicity, low-effective dosage required, and a high degree of manipulability. Although also used for imaging and diagnostics, nanoparticles' utility as a drug or genetic delivery system is of particular interest in transplantation medicine. Currently, researchers are exploring options to integrate nanoparticles into both diagnostics and therapy for both grafts ex-situ before transplantation and for patients following transplantation. These studies have demonstrated that nanoparticles can mitigate damage to organs and patients through a large variety of mechanisms-ranging from the induction of cellular genetic changes to the enhancement of immunosuppressive drug delivery. Specifically, with the advent of machine perfusion preservation ex vivo, treatment of the graft became a very attractive approach and nanoparticles have great potential. However, before nanoparticles can be translated into clinical use, their short-term and long-term toxicity must be thoroughly characterized, especially with regards to their interactions with other biological molecules present in the human body.

Mitochondria as Therapeutic Targets in Transplantation

Advances in surgical procedures, technology, and immune suppression have transformed organ transplantation. However, the metabolic changes that occur during organ retrieval, storage, and implantation have been relatively neglected since the developments many decades ago of cold storage organ preservation solutions. In this review we discuss how the metabolic changes that occur within the organ during transplantation, particularly those associated with mitochondria, may contribute to the outcome. We show how a better understanding of these processes can lead to changes in surgical practice and the development of new drug classes to improve the function and longevity of transplanted grafts, while increasing the pool of organs available for transplantation.

Immunosuppression in uterine transplantation

Uterine transplantation (UTx) is the only effective treatment for uterine infertility patients to become genetic mothers. After decades of research, the surgical methods of UTx are very developed. There are numerous factors that affect the results of UTx, such as selection of the donor uterus before transplantation, immunosuppressive therapy post-transplantation, rejection monitoring, and immune tolerance. Studies have shown that immune rejection is a crucial factor affecting the survival rate after organ transplantation. Unlike liver or kidney transplantation, the aim of UTx is to obtain a functional uterus that is able to support successful pregnancy and birth of a healthy fetus. Because of the unique purpose of UTx, its immunosuppressive program is relatively specialized. Some immunosuppressive agents can cause perinatal complications, and inducing immune tolerance is necessary to resolve these side effects. Further understanding of the immune mechanism of UTx and the continuous development of new immunosuppressive agents, combined with the application of assisted reproductive technology, will be more conducive to the realization of UTx to breed offspring.

Cellular Mechanisms of Rejection of Optic and Sciatic Nerve Transplants: An Observational Study

Background.

Organ transplantation is a standard therapeutic strategy for irreversible organ damage, but the utility of nerve transplantation remains generally unexplored, despite its potential benefit to a large patient population. Here, we aimed to establish a feasible preclinical mouse model for understanding the cellular mechanisms behind the rejection of peripheral and optic nerves.

Methods.

We performed syngenic and allogenic transplantation of optic and sciatic nerves in mice by inserting the nerve grafts inside the kidney capsule, and we assessed the allografts for signs of rejection through 14 d following transplantation. Then, we assessed the efficacy of CTLA4 Ig, Rapamycin, and anti-CD3 antibody in suppressing immune cell infiltration of the nerve allografts.

Results.

By 3 d posttransplantation, both sciatic and optic nerves transplanted from BALB/c mice into C57BL/6J recipients contained immune cell infiltrates, which included more CD11b⁺ macrophages than CD3⁺ T cells or B220⁺ B cells. Ex vivo immunogenicity assays demonstrated that sciatic nerves demonstrated higher alloreactivity in comparison with optic nerves. Interestingly, optic nerves contained higher populations of anti-inflammatory PD-L1⁺ cells than sciatic nerves. Treatment with anti-CD3 antibody reduced immune cell infiltrates in the optic nerve allograft, but exerted no significant effect in the sciatic nerve allograft.

Conclusions.

These findings establish the feasibility of a preclinical allogenic nerve transplantation model and provide the basis for future testing of directed, high-intensity immunosuppression in these mice.

Paired kidney exchange transplantation - pushing the boundaries

The scarcity of living organ donors makes it imperative to develop newer innovations to optimize and maximize the utilization of the available pool. ABO and HLA sensitization are important immunological barriers in renal transplant and can potentially lead to rejection of almost one-third of the willing living donors. Paired kidney exchange (PKE) is a rapidly growing method used to overcome these barriers and has grown in popularity over the last three decades since its introduction in 1986. Evolution of the matching strategies and use of complex algorithms has led to increase in the number of possible matches thereby benefiting multiple recipients. The use of altruistic donors and compatible pairs has also helped in increasing the possible exchanges. This review provides an in-depth analysis of the evolution, the present global scenario, and the future of PKE. It also discusses the recent trends of advanced donation, trans-organ paired exchange and global kidney exchange and the associated ethical concerns.

Effectiveness of Interventional Strategies in Modulating Knowledge and Attitude of Health Care Professionals for Promoting Organ Donation: A Study in Tertiary Care Public Hospital of North India

Objective:

To evaluate the impact of interventional “educational module” on knowledge and attitude regarding organ donation amongst resident doctors and nurses in the Institute of National Importance.

Study Design:

Interventional and prospective.

Methods:

We devised an interactive educational module covering various aspects of organ donation through a series of audiovisual lectures and information booklets. Resident doctors and nurses posted in those areas of the 1948-bedded Postgraduate Institute of Medical Education and Research (PGIMER), where head injury patients were treated and were subject to intervention using this module. The pre and postinterventional scores of their knowledge and attitude regarding organ donation were compared to find out impact of the intervention.

Results:

A total of 242 nurses and 87 resident doctors participated in this research. Higher knowledge score was observed preintervention amongst doctors as compared to nurses. Significant improvement was seen in total knowledge scores of both groups postintervention. Doctors had better scores for the “concept of organ donation,” while nurses were more familiar with “procedures and protocols.” Both had low knowledge about “clinical criteria for brain death” and “legal issues” preintervention which improved significantly postintervention. The positive impact of intervention was also observed on attitude in both categories. A significant impact of intervention was observed on overall propensity of doctors and nurses to promote organ donation, for pledging their own organs and for counseling of the patient/attendants on this cause.

Conclusion:

Scientifically designed educational modules have a promising role in improving awareness and attitude of health care professionals regarding organ donation and their propensity to be prospective donors, effective counselors, and advocates of organ donation.