Xenotransplantation of mitochondria: A novel strategy to alleviate ischemia-reperfusion injury during ex vivo lung perfusion

BACKGROUND

Ischemia-reperfusion injury (IRI) plays a crucial role in the development of primary graft dysfunction (PGD) following lung transplantation. A promising novel approach to optimize donor organs before transplantation and reduce the incidence of PGD is mitochondrial transplantation.

METHODS

In this study, we explored the delivery of isolated mitochondria in 4 hours ex vivo lung perfusion (EVLP) before transplantation as a means to mitigate IRI. To provide a fresh and viable source of mitochondria, as well as to streamline the workflow without the need for donor muscle biopsies, we investigated the impact of autologous, allogeneic, and xenogeneic mitochondrial transplantation. In the xenogeneic settings, isolated mitochondria from mouse liver were utilized while autologous and allogeneic sources came from pig skeletal muscle biopsies.

RESULTS

Treatment with mitochondrial transplantation increased the P/F ratio and reduced pulmonary peak pressure of the lungs during EVLP, compared to lungs without any mitochondrial transplantation, indicating IRI mitigation. Extensive investigations using advanced light and scanning electron microscopy did not reveal evidence of acute rejection in any of the groups, indicating safe xenotransplantation of mitochondria.

CONCLUSIONS

Future work is needed to further explore this novel therapy for combating IRI in lung transplantation, where xenotransplantation of mitochondria may serve as a fresh, viable source to reduce IRI.

Engineering considerations in the design of tissue specific bioink for 3D bioprinting applications

Over eight million surgical procedures are conducted annually in the United Stats to address organ failure or tissue losses. In response to this pressing need, recent medical advancements have significantly improved patient outcomes, primarily through innovative reconstructive surgeries utilizing tissue grafting techniques. Despite tremendous efforts, repairing damaged tissues remains a major clinical challenge for bioengineers and clinicians. 3D bioprinting is an additive manufacturing technique that holds significant promise for creating intricately detailed constructs of tissues, thereby bridging the gap between engineered and actual tissue constructs. In contrast to non-biological printing, 3D bioprinting introduces added intricacies, including considerations for material selection, cell types, growth, and differentiation factors. However, technical challenges arise, particularly concerning the delicate nature of living cells in bioink for tissue construction and limited knowledge about the cell fate processes in such a complex biomechanical environment. A bioink must have appropriate viscoelastic and rheological properties to mimic the native tissue microenvironment and attain desired biomechanical properties. Hence, the properties of bioink play a vital role in the success of 3D bioprinted substitutes. This review comprehensively delves into the scientific aspects of tissue-centric or tissue-specific bioinks and sheds light on the current challenges of the translation of bioinks and bioprinting.

Using data envelopment analysis and the bootstrap method to evaluate organ transplantation efficiency in Brazil

Brazil has the most extensive public program for organ transplantation in the world, and the Brazilian National Health System (SUS) provides full coverage of all costs involved in organ donation, transplants, and post-transplant. Despite the relevance of the subject and the shortage of organs for transplants, transplantation process efficiency assessments are still uncommon in Brazil and abroad. This study aims to evaluate the efficiency of the Brazilian states and the Federal District in transforming potential organ donors into actual donations. We applied data envelopment analysis (DEA) in conjunction with the bootstrap technique, using organ transplantation data from 2018. The bootstrap methods applied (bootstrap technique, the bootstrap-biased scores of efficiency, and the bootstrap bias-corrected scores of efficiency) allow to obtain a confidence interval for DEA scores and provide greater robustness to studies based on DEA methodology. The bootstrap bias-corrected model indicates that there is significant room for improvement in terms of converting potential donors into actual donors. The mean corrected score is 0.55, signalizing that altogether the Brazilian states could maximize in 45% the number of transplanted organs without necessarily increasing the pool of potential donors. The study provides insights into the Brazilian processes of organ donation and transplantation, helping to identify locations in need of resource allocation improvements. Given the scarcity of studies with a joint application of DEA and bootstrap techniques in this crucial health activity, we also intend to methodologically contribute to this type of benchmark analysis, emphasizing the importance of considering measurement errors, randomness, and bias at DEA models.

Transportation of Donated Hearts by Drone in Comparison to Road-Bound Vehicles in Mexico City

Background:

Organ transportation between hospitals has many challenges since the harvested organ needs to be transplanted to the recipient within an optimal time frame. It is important to transfer the organ from the donor to the recipient site quickly and professionally.

Aim:

The aim of this research is to investigate whether the transportation of donated hearts by drones is more efficient than transportation using road-bound vehicles.

Methods:

A simulation using MatLab software was performed to calculate the heart transportation time between three different hospitals in Mexico City by road-bound vehicles and by drones. This simulation was performed to demonstrate how congestion and traffic in Mexico City prevent healthy hearts from being transplanted to patients on time. The 24-hour period was divided into four 5-hour periods and these were chosen to be: Period 1 (22:00-03:00), Period 2 (04:00-09:00), Period 3 (10:00-15:00) and Period 4 (16:00-21:00).

Results:

The time it took to travel between the hospitals by car within each of the 5-hour periods was calculated. It was observed that, in period 2, a high volume of traffic was present causing road-bound vehicles to take a longer time to deliver hearts to hospitals. All hospitals were within reach of each other if the hearts were to be transported by drone and the delivery time by drone in all cases was less than 1.88 hours, which is the optimum time for the harvested heart to be transported without risk from the donor to the recipient.

Conclusion:

Using drones will increase the safety of transplants, reduce the heart transplantation waiting list and eventually, heart transplantation may be possible in different areas of the city at rush hour times.

Evaluation on the Use of Italian High-Speed Rail to Support Transportation Network for Transplantation Activities

BACKGROUND

One of the main activities connected with transplantation is the rapid and timely transportation of patients, medical teams, and human organs from donation to transplantation centers under the compliance of national guidelines and principles of quality, performance, and safety. High-speed transportation on a railway network is becoming relevant both in terms of performance and extensiveness of the service.

METHODS AND OBJECTIVES

Our study explores the feasibility of adopting a high-speed rail network for the transportation of those organs with large cold ischemia time and those less influenced by transportation-related perturbations (ie, temperature, speed, vibrations), assessing savings and relative performance improvement. In this study, only kidneys have been considered; the transplantation database has been integrated with the national high-speed railway network and timetables. A function is implemented that allocates to air transportations those records with 1 of the 2 ends situated on islands, remote regions, and abroad, while rail transportation is preferred where constraints on capacity and compliance with cold ischemia time are met. Road transportation is still feasible for those records involving 2 adjacent regions and for intraregional transportation.

RESULTS

The opportunity of integrated road-rail transportation in place of air or all-road transportation allows users to lower generalized costs and reduce driven distance for personnel and vehicles allocated to a regional transplantation center's fleet and staff. Savings in fleet and staff usage can serve to improve the performances at the local level.

CONCLUSIONS

The knowledge and analysis of transportation alternatives for human organs with less stringent safety and preservation criteria allow a more efficient allocation of resources both at the local and national level-without compromising quality and reliability of the system.