黑料网

Organ transplantation; Donor selection; HLA matching; Expanded criteria donors; Living donors; Deceased donors; Immunological compatibility; Graft survival; Recipient outcomes; Donor characteristics

Introduction

Organ transplantation has become a life-saving therapy for patients with end-stage organ failure. However, the success of transplantation is significantly influenced by the careful selection of appropriate donors [1]. The ideal donor is one who minimizes the risk of immunological rejection, transmits no infectious diseases, and provides a high-quality organ with optimal function. Donor selection involves a comprehensive evaluation process, considering various factors such as donor age, medical history, cause of death (in deceased donors), organ function, and immunological compatibility with the recipient [2].

The type of donor, whether deceased or living, also influences the selection process. Deceased donors can be classified as brain-dead donors (DBD) or donation after circulatory death (DCD) donors. Each type has specific criteria and considerations. Living donation, primarily for kidney and liver transplantation, offers the advantage of planned surgery and shorter ischemic time, but requires careful evaluation of the donor's health and psychological well-being [3].

Description

Immunological compatibility between the donor and recipient is a crucial determinant of transplant success. Human leukocyte antigens (HLA), a group of genes on chromosome 6 that play a key role in the immune response, are routinely matched between donors and recipients [4]. Better HLA matching is generally associated with reduced risk of rejection and improved graft survival, particularly in kidney transplantation. However, with advancements in immunosuppressive therapies, the importance of perfect HLA matching has somewhat diminished, especially in other organ transplants like heart and liver.

Donor age is another important factor. While younger donors are generally preferred due to better organ quality, the increasing shortage of organs has led to the acceptance of older donors, known as expanded criteria donors (ECD) [5]. ECDs, which include donors older than 60 years or donors aged 50-59 with specific comorbidities, present a higher risk of primary graft dysfunction and other complications. Careful evaluation of organ function and recipient risk factors is essential when considering ECDs.

Donor medical history, including pre-existing conditions such as hypertension, diabetes, and infections, also plays a critical role in donor selection. Transmission of infections from the donor to the recipient is a serious complication. Thorough screening for infectious diseases, including HIV, hepatitis B, and hepatitis C, is mandatory for all potential donors [6].

Discussion

The impact of donor selection on transplant outcomes varies depending on the organ transplanted. In kidney transplantation, HLA matching remains a significant factor, with better matches associated with improved long-term graft survival. In liver transplantation, donor age and steatosis (fatty liver) are important considerations. In heart and lung transplantation, donor age, ischemic time, and lung function are critical factors [7].

The use of ECDs has expanded the donor pool and allowed more patients to receive transplants. However, it is crucial to carefully balance the benefits of expanding the donor pool with the potential risks associated with using ECD organs. Careful recipient selection and tailored immunosuppressive strategies are essential when using ECDs.

Living donation offers several advantages, including shorter ischemic time, planned surgery, and the opportunity for pre-emptive transplantation (before the recipient requires dialysis). However, ensuring donor safety and preventing coercion are paramount [8]. Thorough medical and psychological evaluation of potential living donors is crucial.

The development of new technologies, such as machine perfusion for organ preservation, has allowed for better assessment of organ viability and function before transplantation. This can help to improve donor selection by identifying organs that are more likely to function well after transplantation [9].

Future research should focus on several key areas to further refine donor selection strategies. Developing more accurate and non-invasive methods for assessing organ quality and function is crucial. Further research is needed to better understand the impact of donor genetics and epigenetics on transplant outcomes. The use of artificial intelligence and machine learning to analyze large datasets of donor and recipient information can help to develop more sophisticated donor-recipient matching algorithms [10].

Developing strategies to mitigate the risks associated with ECDs is also an important area of research. This includes exploring new preservation techniques, optimizing immunosuppressive strategies, and developing biomarkers to predict graft function. Further research is needed to develop more targeted and personalized approaches to donor selection, taking into account individual recipient characteristics and risk factors.

Conclusion

Donor selection plays a crucial role in determining the success of organ transplantation. Careful evaluation of donor characteristics, immunological compatibility, and organ function is essential to minimize the risk of complications and optimize graft and recipient outcomes. The use of ECDs and living donation has expanded the donor pool and allowed more patients to receive transplants. Continued research and innovation in donor selection strategies, including the development of new technologies and personalized approaches, will further improve transplant success rates and enhance the lives of transplant recipients.

Acknowledgement

None

Conflict of Interest

None

References

1. Zielińska K, Kukulski L, Wróbel M, Przybyłowski P, Rokicka D, et al. (2022) Carbohydrate Metabolism Disorders in Relation to Cardiac Allograft Vasculopathy (CAV) Intensification in Heart Transplant Patients According to the Grading Scheme Developed by the International Society for Heart and Lung Transplantation (ISHLT). Ann Transplant 27: 933420.

Indexed at, Google Scholar, Crossref

2. Raffa GM, Di Gesaro G, Sciacca S, Tuzzolino F, Turrisi M, et al. (2016) Heart transplant program at IRCCS-ISMETT: Impact of mechanical circulatory support on pre- and post -transplant survival. Int J Cardiol 219: 358-361.

Indexed at, Google Scholar, Crossref

3. Kitamura S (2012) Heart transplantation in Japan: a critical appraisal for the results and future prospects. Gen Thorac Cardiovasc Surg 60: 639-644.

Indexed at, Google Scholar, Crossref

4. Delgado JF, Reyne AG, de Dios S, López-Medrano F, Jurado A, et al. (2015) Influence of cytomegalovirus infection in the development of cardiac allograft vasculopathy after heart transplantation. J Heart Lung Transplant 3:1112-1119.

Indexed at, Google Scholar, Crossref

5. Wever-Pinzon O, Edwards LB, Taylor DO, Kfoury AG, Drakos SG, et al. (2017) Association of recipient age and causes of heart transplant mortality: Implications for personalization of post-transplant management-An analysis of the International Society for Heart and Lung Transplantation Registry. J Heart Lung Transplant 36: 407-417.

Indexed at, Google Scholar, Crossref

6. Saczkowski R, Dacey C, Bernier PL (2010) Does ABO-incompatible and ABO-compatible neonatal heart transplant have equivalent survival. Interact Cardiovasc Thorac Surg 10: 1026-1033.

Indexed at, Google Scholar, Crossref

7. Jeewa A, Manlhiot C, Kantor PF, Mital S, McCrindle BW, et al. (2014) Risk factors for mortality or delisting of patients from the pediatric heart transplant waiting list. J Thorac Cardiovasc Surg 147: 462-468.

Indexed at, Google Scholar, Crossref

8. Conway J, Manlhiot C, Kirk R, Edwards LB, McCrindle BW, et al. Mortality and morbidity after retransplantation after primary heart transplant in childhood: an analysis from the registry of the International Society for Heart and Lung Transplantation. J Heart Lung Transplant 33: 241-251.

Indexed at, Google Scholar, Crossref

9. R D Vanderlaan, C Manlhiot, L B Edwards, J Conway, B W McCrindle, et al. (2015) Risk factors for specific causes of death following pediatric heart transplant: An analysis of the registry of the International Society of Heart and Lung Transplantation. Pediatr Transplant 19: 896-905.

Indexed at, Google Scholar, Crossref

10. Sivathasan C, Lim CP, Kerk KL, Sim DK, Mehra MR, et al. (2017) Mechanical circulatory support and heart transplantation in the Asia Pacific region. J Heart Lung Transplant 36: 13-18.

Indexed at, Google Scholar, Crossref