Human organ transplantation: background and consequences

Joseph Murray: Pioneering Plastic Surgeon and Father of the First Organ Transplant

Dr. Joseph Murray was a plastic surgeon who is best known for performing the first successful human organ transplant. After graduating from Harvard Medical School and completing a surgical internship at Peter Bent Brigham Hospital, Murray enlisted in the US Army Medical Corp and spent 5 years at Valley Forge General Hospital treating World War II soldiers injured in combat. He treated hundreds of burn victims with skin grafts and took an interest in the variable process of graft rejection based on both the patient's relation to the graft donor and the patient's level of immunocompetency. His work at Valley Forge set the stage for his research investigating the feasibility of kidney transplantation and immunosuppression. He went on to perform the first successful kidney transplant between identical twins in 1954, between fraternal twins in 1959, and between an unrelated donor and recipient in 1962. For his efforts, he was awarded the 1990 Nobel Prize in Medicine.

A Short History of Skin Grafting in Burns: From the Gold Standard of Autologous Skin Grafting to the Possibilities of Allogeneic Skin Grafting with Immunomodulatory Approaches

Due to groundbreaking and pioneering developments in the last century, significant improvements in the care of burn patients have been achieved. In addition to the still valid therapeutic standard of autologous split-thickness skin grafting, various commercially available skin substitutes are currently available. Significant progress in the field of tissue engineering has led to the development of promising therapeutic approaches. However, scientific advances in the field of allografting and transplant immunology are of great importance. The achievement of various milestones over the past decades has provided thought-provoking impulses in the field of skin allotransplantation. Thus, biologically viable skin allotransplantation is still not a part of the clinical routine. The purpose of this article is to review the achievements in burn surgery with regards to skin allotransplantation in recent years.

Immune cell function assays in the diagnosis of infection in pediatric liver transplantation: an open-labeled, two center prospective cohort study

BACKGROUND

Limited studies have been performed in assessment of immune status of pediatric liver transplants (PLTs). We conducted this study to evaluate Cylex immune cell function assay in diagnosis of infection and its potential clinical application in Chinese infant PLTs.

METHODS

In this prospective cohort study, 227 infant PLTs from two medical centers were enrolled, and 216 completed the study. Cylex ATP values were measured before and after liver transplantation (LT) at week 1, 2, 3, 4, 8, 12 and 24 respectively. Accordingly, patients' clinical records, including demographic data, liver function results, tacrolimus dosages and concentrations were collected and analyzed.

RESULTS

One hundred and sixty of 216 PLTs (74.1%) were diagnosed infection based on the parameters including abnormal vital signs, imaging changes, and pathogens detection, while 44 (20.4%) were clinically stable and 12 (5.6%) experienced acute rejection. The median Cylex ATP value in infant PLTs post-surgery reduced significantly in infection group compared to stable group (median, 137 vs. 269 ng/mL, P<0.001). Receiver operating characteristic (ROC) curve analysis determined that the cut-off value of Cylex ATP was 152 ng/mL in diagnosis of infection [area under the curve (AUC): 0.784, 95% CI: 0.720-0.848]. Meanwhile, Cylex ATP value showed no correlation to tacrolimus dosage, blood concentration, dose-normalized concentration/dose ratio or Kaup index. However, it tended to correlate weakly with the white blood cell (WBC) number (R =0.462, P<0.0001) and lymphocyte counts (R =0.363, P<0.0001).

CONCLUSIONS

In this study, we demonstrated that low Cylex ATP represented partly over-immunosuppression and had diagnostic value in infant PLTs with infections, which might assist individualized immunosuppression in PLT patients.

The Freemartin Cattle and Clinical Transplantation: From the Ancients to Modern Day

This historical retrospective explores the study of the freemartin condition and its impact on the discovery of immunologic tolerance and the field of transplant surgery-from the ancient Romans, to early modern anatomists Valsalva, Scarpa, and Hunter, to contemporary immunologists Owen, Medawar, and Billingham, and to legendary transplant surgeon Joseph Murray. The legacy of freemartin cattle in the understanding of acquired tolerance and transplant immunology represents generations of scientific inquiry guided by careful observation and occasional serendipity, and the present-day immunologists and surgeons exploring immune transplant tolerance owe much to the history of the freemartin, several millennia in the making.

Innate Immune Determinants of Graft-Versus-Host Disease and Bidirectional Immune Tolerance in Allogeneic Transplantation

The success of tissue transplantation from a healthy donor to a diseased individual (allo-transplantation) is regulated by the immune systems of both donor and recipient. Developing a state of specific non-reactivity between donor and recipient, while maintaining the salutary effects of immune function in the recipient, is called “immune (transplantation) tolerance”. In the classic early post-transplant period, minimizing bidirectional donor ←→ recipient reactivity requires the administration of immunosuppressive drugs, which have deleterious side effects (severe immunodeficiency, opportunistic infections, and neoplasia, in addition to drug-specific reactions and organ toxicities). Inducing immune tolerance directly through donor and recipient immune cells, particularly via subsets of immune regulatory cells, has helped to significantly reduce side effects associated with multiple immunosuppressive drugs after allo-transplantation. The innate and adaptive arms of the immune system are both implicated in inducing immune tolerance. In the present article, we will review innate immune subset manipulations and their potential applications in hematopoietic stem cell transplantation (HSCT) to cure malignant and non-malignant hematological disorders by inducing long-lasting donor ←→ recipient (bidirectional) immune tolerance and reduced graft-versus-host disease (GVHD). These innate immunotherapeutic strategies to promote long-term immune allo-transplant tolerance include myeloid-derived suppressor cells (MDSCs), regulatory macrophages, tolerogenic dendritic cells (tDCs), Natural Killer (NK) cells, invariant Natural Killer T (iNKT) cells, gamma delta T (γδ-T) cells and mesenchymal stromal cells (MSCs).

Pretransplant defunctionalized bladder-overrated condition?

AIMS

The objective of this study was to evaluate the expression of bladder receptors in patients with defunctionalized bladder (DB) and to assess voiding behavior after refunctionalization.

METHODS

A total of 68 pretransplant patients were divided in two groups: DB (diuresis <300 mL/24 h; n = 33) and NDB (non-DB; diuresis ≥300 mL/24 h; n = 35). A sample of mucosa and detrusor at the site of the future ureteral implantation was collected. The following receptors were assessed by real-time polymerase chain reaction (qRT-PCR): M₂ , M₃ , α_1D , β₃ , P2X₂ , P2X₃ , TRPV1, TRPV4, TRPA1, and TRPM8. At 3, 6, and 12 months after transplant patients answered IPSS and ICIQ-OAB questionnaires and filled a 3-day 24 h frequency/volume chart (FVC) at 6 and 12 months.

RESULTS

The expression of all receptors in the mucosa and in the detrusor was similar in both groups, except from α_1D , which was overexpressed in the detrusor of DB relatively to NDB group. ICIQ-OAB symptom score was similar between the groups at 3, 6, and 12 months. There was a reduction of this score in both groups with time. The same pattern was found for IPSS score. Bother scores were similar between groups. No difference was observed for all FVC parameters between DB and NDB patients.

CONCLUSION

Gene expression of bladder receptors involved in micturition control was similar in patients with or without DB. Bladder behavior had a similar pattern independently of pretransplant residual diuresis. These findings question the relevance of the term DB in pretransplant patients.

Transplant tolerance: new insights and strategies for long-term allograft acceptance

One of the greatest advances in medicine during the past century is the introduction of organ transplantation. This therapeutic strategy designed to treat organ failure and organ dysfunction allows to prolong the survival of many patients that are faced with no other treatment option. Today, organ transplantation between genetically dissimilar individuals (allogeneic grafting) is a procedure widely used as a therapeutic alternative in cases of organ failure, hematological disease treatment, and some malignancies. Despite the potential of organ transplantation, the administration of immunosuppressive drugs required for allograft acceptance induces severe immunosuppression in transplanted patients, which leads to serious side effects such as infection with opportunistic pathogens and the occurrence of neoplasias, in addition to the known intrinsic toxicity of these drugs. To solve this setback in allotransplantation, researchers have focused on manipulating the immune response in order to create a state of tolerance rather than unspecific immunosuppression. Here, we describe the different treatments and some of the novel immunotherapeutic strategies undertaken to induce transplantation tolerance.

Twin Transplants; Twin Study Summary; Human Interest Topics

An overview of the nature and success of organ transplantation in monozygotic (MZ) twins is presented. Recent timely examples demonstrate the unique donor–recipient relationship shared by MZ co-twins. Next, a recent analysis of MZ co-twin differences in the epigenetic profile and associations with differences in life history factors is presented. This work has been the focus of considerable attention by scientists and the media. The final section of this column summarizes information and events concerning twins' longevity, screen careers, older parenting of twins and the origin of the word ‘twin’.

The endogenous pro-resolving mediators lipoxin A4 and resolvin E1 preserve organ function in allograft rejection

Allograft rejection remains a major limitation to successful solid organ transplantation. Here, we investigated the biosynthesis and bioactions of the pro-resolving mediators lipoxin A(4) and resolvin E1 in host responses to organ transplantation. In samples obtained during screening bronchoscopy after human lung transplantation, bronchoalveolar lavage fluid levels of lipoxin A(4) were increased in association with the severity of allograft rejection that was graded independently by clinical pathology. Lipoxin A(4) significantly inhibited calcineurin activation in human neutrophils, and lipoxin A(4) stable analogs prevented acute rejection of vascularized cardiac and renal allografts. Transgenic animals expressing human lipoxin A(4) receptors revealed important sites of action in host tissues for lipoxin A(4)'s protective effects. Resolvin E1 displays counter-regulatory actions for leukocytes, in part, via increased lipoxin A(4) biosynthesis, yet RvE1 administered (1μg, iv) to donor (days -1 and 0) and recipient mice (days -1, 0 and +4) was even more potent than a lipoxin stable analog (1μg, iv) in prolonging renal allograft survival (median survival time=74.0 days with RvE1 and 37.5 days with a LXA(4) analog). Together, these results highlight the potential for pro-resolving mediators in prolonging survival of solid organ transplants.

Kidney transplantation in the context of renal replacement therapy

Kidney transplantation has dramatically evolved from a life-saving yet unproven therapy for patients with renal failure to a mature field that is the preferred treatment for those suffering from ESRD. Patients who receive a transplant experience a 68% lower risk of death compared with those waiting on dialysis for a transplant. This benefit is afforded to all patient subgroups including the elderly (> or =70 yr), and diabetics, who can gain 11 yr of extra life with transplantation. Prolonged transplant wait times result in a higher risk of death but this can be ameliorated with preemptive transplantation. Future challenges will focus on appropriate organ allocation and addressing long-term renal function and comorbid conditions so patients can enjoy the full benefits of transplantation.

Mini-incisions by lombotomy or subcostal access in living kidney donors: a randomized trial comparing pain, safety, and quality of life

OBJECTIVES

The aim of this study was to compare two mini-incision techniques and judge the impact on the quality of life, pain, and safety of living kidney donors.

PATIENTS AND METHODS

From March through September 2003, a prospective randomized study with 60 donors had nephrectomy performed - 30 through a lombotomy and another 30 patients underwent subcostal mini-incisions. The same anesthetic procedure was used for both groups. All patients were evaluated from baseline (T0) to day 90 after surgery. Pain evaluation included visual analog scale (VAS) and drug usage. To assess quality of life (QOL), the questionnaire SF-36 was used and surgical outcomes were also checked.

RESULTS

Sixty patients (41.6 +/- 8.9 yr old) were included in the protocol. Regarding incision length and blood loss, no statistical difference was observed. However, irrespective to the site of the mini-incision, patients with body mass index (BMI) higher than 25 kg/m(2) had significantly longer incision length as well as higher blood loss. There were no complications. No significant difference in tramadol or in pain perception was observed between groups. QOL was also not different between groups, however, there was a significant loss with subsequent return to baseline levels.

CONCLUSION

The position of the mini-incision (lombotomy or subcostal) has no significant impact on surgical outcomes, pain perception, and QOL of living kidney donors. Mini-incision techniques represent fast and safe approaches to perform nephrectomy in the healthy population. Special care must be taken in obese patients in order to minimize surgical complications.

The human genome and gene expression profiling

The mapping and sequencing of the human genome has generated a large resource for answering questions about human disease. This achievement is akin in scientific importance to developing the periodic table of elements. Plastic surgery has always been at the frontier medical research. This resource will help us to improve our understanding on the many unknown physiological and pathogical conditions we deal with daily, such as wound healing keloid scar formation, Dupuytren's disease, rheumatoid arthritis, vascular malformation and carcinogenesis. We are primed in obtaining both disease and normal tissues to use this resource and applying it to clinical use. This review is about the human genome, the basis of gene expression profiling and how it will affect our clinical and research practices in the future and for those embarking on the use of this new technology as a research tool, we provide a brief insight on its limitations and pitfalls.

Maintenance immunosuppression: new agents and persistent dilemmas

Since the approval of cyclosporine in 1983, only 3 drugs, mycophenolate mofetil, tacrolimus, and sirolimus, have been approved for maintenance immunosuppression in renal transplant recipients. All 3 agents decrease the incidence of early acute allograft rejection. An increase in intermediate and long-term graft survival has not been shown. However, survival data from these clinical trials should be interpreted with caution because the studies were not designed for this purpose. All 3 drugs have significant, albeit different, safety profiles. It remains to be seen whether, the lower incidence of hypertension and hyperlipidemia seen in tacrolimus-treated patients will reduce the incidence and severity of the cardiovascular disease experienced by renal transplant recipients. Sirolimus causes severe hyperlipidemia, and the long-term consequences both on the pathogenesis of cardiovascular disease and on lipid-associated renal injury have yet to be determined. Tacrolimus and mycophenolate mofetil appear to increase graft survival in pancreas-kidney recipients but their efficacy in another high-risk group, African-American recipients, has not yet been clearly shown. However, the trend toward improved graft survival in African-American recipients treated with tacrolimus is encouraging. Steroid-withdrawal remains a goal in the posttransplant period. The available data from steroid-withdrawal and steroid-avoidance clinical trials are mixed. Steroid withdrawal can be achieved in about 50% of patients on a cyclosporine-based immunosuppression regimen. Steroid-withdrawal under coverage of tacrolimus, mycophenolate mofetil or Neoral (Novartis Pharmaceuticals, East Hanover, NJ) may be more successful than that achieved in patients receiving Sandimmune (Novartis Pharmaceuticals). Further studies are needed in this area.