Living Donor Lung Transplantation After Hematopoietic Stem Cell Transplantation From the Same Donor: A Risk Worth Taking.

Living donor (LD) lung transplantation (LT) represents an exceptional procedure in Western countries. However, in selected situations, it could be a source of unique advantages, besides addressing organ shortage. We report a successful case of father-to-child single-lobe LT, because of the complications of hematopoietic stem cell transplantation from the same donor, with initial low-dose immunosuppressive therapy and subsequent early discontinuation. Full donor chimerism was hypothesized to be a mechanism of transplant tolerance, and this postulated immunological benefit was deemed to outweigh the risks of living donation and the possible drawbacks of single compared with bilateral LT. Favorable size matching and donor's anatomy, accurate surgical planning, and specific expertise in pediatric transplantation also contributed to the optimal recipient and donor outcomes. Ten months after LD LT, the patient's steadily good lung function after withdrawal of immunosuppressive therapy seems to confirm the original hypothesis.

Donor Lung Preservation at 10°C: Clinical and Logistical Impact.

INTRODUCTION: Cold static donor lung preservation at 10°C appears to be a promising method to safely extend the cold ischemic time (CIT) and improve lung transplant (LTx) logistics. METHODS: LTx from November 2021 to February 2023 were included in this single institution, prospective, non-randomized study comparing prolonged preservation at 10°C versus standard preservation on ice. The inclusion criteria for 10°C preservation were suitable grafts for LTx without any donor retrieval concerns. PRIMARY ENDPOINT: primary graft dysfunction (PGD) grade-3 at 72-h. Secondary endpoints: clinical outcomes, cytokine profile and logistical impact. RESULTS: Thirty-three out of fifty-seven cases were preserved at 10°C. Donor and recipient characteristics were similar across the groups. Total preservation times (h:min) were longer (p<0.001) in the 10°C group [1st lung: median 12:09 (IQR 9:23-13:29); 2nd: 14:24 (12:00-16:20)] vs. standard group [1st lung: median 5:47 (IQR 5:18-6:40); 2nd: 7:15 (6:33-7:40)]. PGD grade-3 at 72-h was 9.4% in 10°C group vs. 12.5% in standard group (p=0.440). Length of mechanical ventilation (MV), ICU and hospital stays were similar in both groups. Thirty and ninety-day mortality rates were 0% in 10°C group (vs. 4.2% in standard group). IL-8 concentration was significantly higher 6-h post-LTx in the standard group (p=0.025) and IL-10 concentration was increased 72-h post-LTx in the 10°C group (p=0.045). CONCLUSIONS: Preservation at 10°C may represent a safe and feasible strategy to intentionally prolong the CIT. In our center, extending the CIT at 10°C may allow for semi-elective LTx and improve logistics with similar outcomes compared to the current standard preservation on ice.

Thyroid hormone protects human lung epithelial cells from cold preservation and warm reperfusion-induced injury.

BACKGROUND: Cellular stress associated with static-cold storage (SCS) and warm reperfusion of donor lungs can contribute to ischemia-reperfusion (IR) injury during transplantation. Adding cytoprotective agents to the preservation solution may be conducive to reducing graft deterioration and improving post-transplant outcomes. METHODS: SCS and warm reperfusion were simulated in human lung epithelial cells (BEAS-2B) by exposing cells to low potassium dextran glucose solution at 4 °C for different periods and then switching back to serum-containing culture medium at 37 °C. Transcriptomic analysis was used to explore potential cytoprotective agents. Based on its results, cell viability, caspase activity, cell morphology, mitochondrial function, and inflammatory gene expression were examined under simulated IR conditions with or without thyroid hormones (THs). RESULTS: After 18 h SCS followed by 2 h warm reperfusion, genes related to inflammation and cell death were upregulated, and genes related to protein synthesis and metabolism were downregulated in BEAS-2B cells, which closely mirrored gene profiles found in thyroid glands of mice with congenital hypothyroidism. The addition of THs (T3 or T4) to the preservation solution increases cell viability, inhibits activation of caspase 3, 8 and 9, preserves cell morphology, enhances mitochondrial membrane potential, reduces mitochondrial superoxide production, and suppresses inflammatory gene expression. CONCLUSION: Adding THs to lung preservation solutions may protect lung cells during SCS by promoting mitochondrial function, reducing apoptosis, and inhibiting pro-inflammatory pathways. Further in vivo testing is warranted to determine the potential clinical application of adding THs as therapeutics in lung preservation solutions.

Various combinations of living and deceased donors for lung retransplantation-a single institutional retrospective study.

OBJECTIVES: Lung retransplantation has been performed as a treatment option mainly for chronic lung allograft dysfunction; however, the outcomes of lung retransplantation have been reported to be worse than those of primary lung transplantation. Because of the scarcity of deceased donors in our country, our lung transplant experience includes both living and deceased donors. Therefore, we have experienced lung retransplantation cases with various combinations of living and deceased donors. The aim of this study was to explore technical pitfalls and outcomes of lung retransplantation in this unique environment. METHODS: We performed 311 lung transplantation procedures between April 2002 and October 2022. Eight lung retransplantation cases (2.6%) were analysed retrospectively. RESULTS: At lung retransplantation, the age of the recipient patients ranged from 11 to 61 years (median, 33 years). The combinations of donor sources (primary lung transplantation/lung retransplantation) were as follows: 2 living/living, 2 deceased/living, 3 living/deceased and 1 deceased/deceased. Seven of 8 patients received lung retransplantation for chronic lung allograft dysfunction. Hospital death occurred in 2 patients (25.0%). The 1-, 3- and 5-year survival rates after lung retransplantation (n = 8) were 75.0%, 75.0% and 75.0%, respectively, while those after primary lung transplantation (n = 303) were 92.8%, 83.4% and 76.4%, respectively (P = 0.162). CONCLUSIONS: Lung retransplantation with various combinations of living and deceased donors is a technically difficult but feasible procedure with acceptable outcomes.

A radiographic score for human donor lungs on ex vivo lung perfusion predicts transplant outcomes.

BACKGROUND: Ex vivo lung perfusion (EVLP) is an advanced platform for isolated lung assessment and treatment. Radiographs acquired during EVLP provide a unique opportunity to assess lung injury. The purpose of our study was to define and evaluate EVLP radiographic findings and their association with lung transplant outcomes. METHODS: We retrospectively evaluated 113 EVLP cases from 2020-21. Radiographs were scored by a thoracic radiologist blinded to outcome. Six lung regions were scored for 5 radiographic features (consolidation, infiltrates, atelectasis, nodules, and interstitial lines) on a scale of 0 to 3 to derive a score. Spearman's correlation was used to correlate radiographic scores to biomarkers of lung injury. Machine learning models were developed using radiographic features and EVLP functional data. Predictive performance was assessed using the area under the curve. RESULTS: Consolidation and infiltrates were the most frequent findings at 1 hour EVLP (radiographic lung score 2.6 (3.3) and 4.6 (4.3)). Consolidation (r = -0.536 and -0.608, p < 0.0001) and infiltrates (r = -0.492 and -0.616, p < 0.0001) were inversely correlated with oxygenation (∆pO2) at 1 hour and 3 hours of EVLP. First-hour consolidation and infiltrate lung scores predicted transplant suitability with an area under the curve of 87% and 88%, respectively. Prediction of transplant outcomes using a machine learning model yielded an area under the curve of 80% in the validation set. CONCLUSIONS: EVLP radiographs provide valuable insight into donor lungs being assessed for transplantation. Consolidation and infiltrates were the most common abnormalities observed in EVLP lungs, and radiographic lung scores predicted the suitability of donor lungs for transplant.

Computed tomography-based machine learning for donor lung screening before transplantation.

BACKGROUND: Assessment and selection of donor lungs remain largely subjective and experience based. Criteria to accept or decline lungs are poorly standardized and are not compliant with the current donor pool. Using ex vivo computed tomography (CT) images, we investigated the use of a CT-based machine learning algorithm for screening donor lungs before transplantation. METHODS: Clinical measures and ex situ CT scans were collected from 100 cases as part of a prospective clinical trial. Following procurement, donor lungs were inflated, placed on ice according to routine clinical practice, and imaged using a clinical CT scanner before transplantation while stored in the icebox. We trained and tested a supervised machine learning method called dictionary learning, which uses CT scans and learns specific image patterns and features pertaining to each class for a classification task. The results were evaluated with donor and recipient clinical measures. RESULTS: Of the 100 lung pairs donated, 70 were considered acceptable for transplantation (based on standard clinical assessment) before CT screening and were consequently implanted. The remaining 30 pairs were screened but not transplanted. Our machine learning algorithm was able to detect pulmonary abnormalities on the CT scans. Among the patients who received donor lungs, our algorithm identified recipients who had extended stays in the intensive care unit and were at 19 times higher risk of developing chronic lung allograft dysfunction within 2 years posttransplant. CONCLUSIONS: We have created a strategy to ex vivo screen donor lungs using a CT-based machine learning algorithm. As the use of suboptimal donor lungs rises, it is important to have in place objective techniques that will assist physicians in accurately screening donor lungs to identify recipients most at risk of posttransplant complications.

Inflation using hydrogen improves donor lung quality by regulating mitochondrial function during cold ischemia phase.

BACKGROUND: Mitochondrial dysfunction results in poor organ quality, negatively affecting the outcomes of lung transplantation. Whether hydrogen benefits mitochondrial function in cold-preserved donors remain unclear. The present study assessed the effect of hydrogen on mitochondrial dysfunction in donor lung injury during cold ischemia phase (CIP) and explored the underlying regulatory mechanism. METHODS: Left donor lungs were inflated using 40% oxygen + 60% nitrogen (O group), or 3% hydrogen + 40% oxygen + 57% nitrogen (H group). Donor lungs were deflated in the control group and were harvested immediately after perfusion in the sham group (n = 10). Inflammation, oxidative stress, apoptosis, histological changes, mitochondrial energy metabolism, and mitochondrial structure and function were assessed. The expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were also analyzed. RESULTS: Compared with the sham group, inflammatory response, oxidative stress, histopathological changes, and mitochondrial damage were severe in the other three groups. However, these injury indexes were remarkably decreased in O and H groups, with increased Nrf2 and HO-1 levels, elevated mitochondrial biosynthesis, inhibition of anaerobic glycolysis and restored mitochondrial structure and function compared with the control group. Moreover, inflation using hydrogen contributed to stronger protection against mitochondrial dysfunction and higher levels of Nrf2 and HO-1 when comparing with O group. CONCLUSIONS: Lung inflation using hydrogen during CIP may improve donor lung quality by mitigating mitochondrial structural anomalies, enhancing mitochondrial function, and alleviating oxidative stress, inflammation, and apoptosis, which may be achieved through activation of the Nrf2/HO-1 pathway.

[Anti-MDA5 antibody-positive rapidly progressive interstitial lung disease after allogeneic hematopoietic cell transplantation successfully treated with triple immunosuppressive therapy].

A 34-year-old man with KMT2A-MLLT1 acute myeloid leukemia in first complete remission underwent allogeneic peripheral blood stem cell transplantation from his HLA-matched sister after conditioning with busulfan/cyclophosphamide. He did not have severe graft-versus-host disease, but he developed interstitial pneumonia six months after transplantation when his oral cyclosporine A (CsA) dose was reduced to 10 mg/day. He was given prednisolone (PSL), which temporarily improved his respiratory condition, but he quickly deteriorated when PSL was reduced. Anti-MDA5 antibody was found to be positive after additional testing, and a three-drug combination of intravenous cyclophosphamide+PSL+CsA was initiated for anti-MDA5 antibody positive rapidly progressive interstitial lung disease, which was effective for interstitial pneumonia. He received a successful living-donor lung transplant from his younger brother and sister. We present a case of rapidly progressive anti-MDA5 antibody positive interstitial lung disease in which the patient's respiratory condition improved after triple therapy and subsequent living-donor lung transplantation.

Emerging Imaging Modalities for Functional Assessment of Donor Lungs Ex Vivo.

The severe shortage of functional donor lungs that can be offered to recipients has been a major challenge in lung transplantation. Innovative ex vivo lung perfusion (EVLP) and tissue engineering methodologies are now being developed to repair damaged donor lungs that are deemed unsuitable for transplantation. To assess the efficacy of donor lung reconditioning methods intended to rehabilitate rejected donor lungs, monitoring of lung function with improved spatiotemporal resolution is needed. Recent developments in live imaging are enabling non-destructive, direct, and longitudinal modalities for assessing local tissue and whole lung functions. In this review, we describe how emerging live imaging modalities can be coupled with lung tissue engineering approaches to promote functional recovery of ex vivo donor lungs.

Preservation and functional maintenance of lung allograft / 器官移植

As the final resolution for end-stage lung disease, lung transplantation can not only significantly prolong the survival, but also remarkably improve the quality of life of recipients. In recent decades, with the advancement of surgical techniques, immunosuppressants and post-transplantation management, the quantity of lung transplantation has been surged around the globe. However, the shortage of donor lung has severely restricted the development of lung transplantation. It is necessary to develop innovative approaches to expand the donor pool. The number of donors and effective preservation and functional maintenance of potential donor lungs play a key role in expanding the donor pool. The quality of donor lung is a critical precondition to ensure the long-term survival of lung transplant recipients. Preservation and functional maintenance of donor lung are of significance for guaranteeing the quality of lung allograft. In this article, research progresses on the management and maintenance of donor lung before procurement, the procurement of donor lung and the preservation and functional maintenance of lung allograft were reviewed, aiming to provide reference for the development of lung transplantation in clinical practice.

Donor neo-atrial cuff construction after accidental lower lobe vein transection.

BACKGROUND: An inadequate donor left atrial cuff is a rare technical issue after graft procurement for lung transplantation. With regard to the shortage of suitable donor organs for lung transplantation, these organs should be surgically reconstructed to avoid the loss of an organ and a futile intervention in the critically ill recipient. CASE PRESENTATION: We report a case of a 62-year old patient who underwent bilateral sequential lung transplantation for chronic obstructive pulmonary disease. During isolated lung procurement, the right inferior pulmonary vein was circumferentially transsected and separated from the right superior pulmonary and middle lobe veins. Subsequently, a reconstruction of the left atrial cuff with an acellular biological patch was performed to complete the atrium anastomosis. The patient experienced an uneventful postoperative recovery and a follow-up ventilation/perfusion scan showed normal perfusion of the right lower lobe. CONCLUSIONS: This case demonstrates that reconstruction of an inadequate left atrial cuff with a biological patch is feasible and allows for an adequate venous drainage and therefore normal transplant organ function.

Heterotopic lung transplant: a feasible approach to compensate for organ shortages.

Lung transplants are still limited by the shortage of suitable donor lungs, especially during the coronavirus disease 2019 pandemic. A heterotopic lung transplant (HLTx), as a flexible surgical procedure, can maximize the potential of donor lungs in an emergency, but its widespread use is hindered by difficulties in anastomosis and paucity of outcome data. We performed a retrospective review of 4 patients, each of whom received an HLTxs over 1 year, including 1 left-to-right single HLTx, 2 right-to-left single HLTxs and 1 lobar HLTx (right upper lobe-to-left). The median recipient age was 58.5 years (46-68); 3 patients were male. The postoperative hospital stay was 33 days (30-42). One recipient lived for 10 years and died of bronchiolitis obliterans syndrome; the others were alive with no major morbidity at 12 to 31 months after the operation with a 1-year survival of 100%. The follow-up chest images showed that transplanted lungs could be inflated well and adapted morphologically to fill the thoracic cavity in the short and long term. This study demonstrates that an HLTx is a feasible alternative to a conventional lung transplant in emergency cases and could be considered in selected patients at advanced medical centres.

Ex Vivo Lung Perfusion: A Review of Current and Future Application in Lung Transplantation.

The number of waitlisted lung transplant candidates exceeds the availability of donor organs. Barriers to utilization of donor lungs include suboptimal lung allograft function, long ischemic times due to geographical distance between donor and recipient, and a wide array of other logistical and medical challenges. Ex vivo lung perfusion (EVLP) is a modality that allows donor lungs to be evaluated in a closed circuit outside of the body and extends lung donor assessment prior to final acceptance for transplantation. EVLP was first utilized successfully in 2001 in Lund, Sweden. Since its initial use, EVLP has facilitated hundreds of lung transplants that would not have otherwise happened. EVLP technology continues to evolve and improve, and currently there are multiple commercially available systems, and more under investigation worldwide. Although barriers to universal utilization of EVLP exist, the possibility for more widespread adaptation of this technology abounds. Not only does EVLP have diagnostic capabilities as an organ monitoring device but also the therapeutic potential to improve lung allograft quality when specific issues are encountered. Expanded treatment potential includes the use of immunomodulatory treatment to reduce primary graft dysfunction, as well as targeted antimicrobial therapy to treat infection. In this review, we will highlight the historical development, the current state of utilization/capability, and the future promise of this technology.

A modified mouse model of orthotopic left lung transplantation based on "pendulum" anastomosis of the reverse-view plane (with video demonstration) / 器官移植

Objective To modify the mouse model of orthotopic left lung transplantation from different perspectives, aiming to establish a simpler, faster and stabler mouse model of lung transplantation. Methods Based on preliminary modified rat model of orthotopic left lung transplantation established by our team, varying extent of modifications were made regarding the tracheal intubation, cannula preparation and anastomosis procedures of orthotopic left lung transplantation in the recipient mice. Orthotopic left lung transplantation in 40 mice were performed by an operator with microsurgical experience. The dissection of the recipient's hilar structure was carried out at the plane of the hilar clamp model within the reverse-view, and the three branches (left main bronchus, pulmonary artery and pulmonary vein) of the pulmonary hilum were anastomosed in turn by the "pendulum" anastomosis method. The operation time of each procedure was recorded. The recipient mice were sacrificed at postoperative 2 weeks, and the incidence of postoperative complications was recorded. Results Lung transplantation was successfully completed in 40 mice, with no bronchial and vascular tearing or twisting, and no bleeding at the anastomosis site. The overall cardiopulmonary procurement time was (10.7±1.5) min, cannula preparation time was (16.2±1.5) min, cold ischemia time was (25.1±2.4) min, warm ischemia time was (19.4±1.6) min, and the total operation time was (57.2±2.9) min, respectively. During the follow-up from 6 to 14 days after surgery, one recipient mouse died of pleural effusion, probably caused by infection. No pneumothorax, thrombosis or atelectasis was found in the remaining recipient mice during postoperative follow-up. Conclusions The modified mouse model of orthotopic left lung transplantation based on "pendulum" anastomosis of the reverse-view plane possesses multiple advantages of short operation time, high success rate and few complications, which is expected to become an alternative model of studying pathological changes after lung transplantation and worthy of further application.

Donor quality assessment and size match in lung transplantation.

Careful donor quality assessment and size match can impact long-term survival in lung transplantation. With this article, we review the conceptual and practical aspects of the preoperative donor lung quality assessment and size matching.

Donor selection for lung transplant in Turkey: Is it necessary to wait for an ideal donor?

BACKGROUND: The aim of this study was to evaluate the donor criteria used in lung transplantation in our clinic. METHODS: A total of 55 cadaveric donors who were accepted for lung transplantation in our clinic between December 2016 and January 2019 were retrospectively analyzed according to ideal donor criteria. The donors were divided into two groups as ideal and non-ideal ones according to their age, partial pressure of oxygen in arterial blood, history of smoking, and ventilation day. Donor data, recipient characteristics and survival outcomes were evaluated. RESULTS: Of 55 donors accepted for lung transplantation, 24 (43.7%) were ideal and 31 (56.3%) were non-ideal donors. The 90-day mortality and one-year survival rates were not significantly different between the two groups. The 90-day mortality was 25% in the ideal group and 22.6% in the non-ideal group (p=0.834). The one-year survival rates after lung transplantation were 64.5% versus 70.6% in the ideal and non-ideal groups, respectively (p=0.444). CONCLUSION: The whole clinical picture should be evaluated before accepting or rejecting donors for lung transplantation. The use of lung donors that do not meet the ideal criteria does not impair short- and mid-term results, compared to ideal lung donors. Strict implementation of donor criteria may prevent using suitable donors for lung transplantation. Use of non-ideal donors can reduce waiting list mortality.

Rapid postmortem ventilation improves donor lung viability by extending the tolerable warm ischemic time after cardiac death in mice.

Uncontrolled donation after cardiac death (uDCD) contributes little to ameliorating donor lung shortage due to rapidly progressive warm ischemia after circulatory arrest. Here, we demonstrated that nonhypoxia improves donor lung viability in a novel uDCD lung transplant model undergoing rapid ventilation after cardiac death and compared the evolution of ischemia-reperfusion injury to mice that underwent pulmonary artery ligation (PAL). The tolerable warm ischemia time at 37°C was initially determined in mice using a modified PAL model. The donor lung following PAL was also transplanted into syngeneic mice and compared with those that underwent rapid ventilation or no ventilation at 37°C before transplantation. Twenty-four hours following reperfusion, lung histology, [Formula: see text]/[Formula: see text] ratio, and inflammatory mediators were measured. Four hours of PAL had little impact on [Formula: see text]/[Formula: see text] ratio and acute lung injury score in contrast to significant injury induced by 5 h of PAL. Four-hour PAL lungs showed an early myeloid-dominant inflammatory signature when compared with naïve lungs and substantially injured 5 h PAL lungs. In the context of transplantation, unventilated donor lungs showed severe injury after reperfusion, whereas ventilated donor lungs showed minimal changes in [Formula: see text]/[Formula: see text] ratio, histologic score, and expression of inflammatory markers. Taken together, the tolerable warm ischemia time of murine lungs at 37°C can be extended by maintaining alveolar ventilation for up to 4 h. Nonhypoxic lung undergoing warm ischemia-reperfusion injury shows an early transcriptional signature of myeloid cell recruitment and extracellular matrix proteolysis before blood-gas barrier dysfunction and significant tissue damage.

Experimental study on the role of IL-10 in improving donor lung function after ex vivo lung perfusion in rats of cardiac death / 器官移植

Objective To evaluate the effect of interleukin (IL)-10 on donor lung function after ex vivo lung perfusion (EVLP) in rats of cardiac death. Methods Twenty adult male SD rats were randomly divided into the simple perfusion group (group A, n=10) and modified perfusion group (group B, n=10). Perfusate A (without IL-10) and perfusate B (supplemented with IL-10) was administered in group A and B, respectively. The EVLP rat models of cardiac death were established. The appearance of donor lung, dry-to-wet (D/W) ratio of donor lung tissues, the function and metabolism of donor lung, the morphology of donor lung and the levels of inflammatory markers of donor lung were statistically compared between two groups. Results After perfusion, evident edema of the whole donor lung, poor compliance and a large amount of edema fluid discharged from the airway were observed in group A, whereas no obvious edema and good compliance were found in group B. Compared with group A, the D/W ratio of lung tissues in group B was higher (P < 0.05). In both groups, the pulmonary vein partial pressure of oxygen reached the peak at 2 h after perfusion, which did not significantly differ between two groups (P > 0.05). In group B, the pulmonary artery pressure was increased at a lower speed and significantly lower after perfusion, and the lactic acid level in the perfusate was significantly lower than those in group A (all P < 0.05). In group A, the alveolar structure was largely destroyed and the cells was rare. In group B, the alveolar structure was relatively normal without evident cell edema. The incidence of cell apoptosis of donor lung was high in group A, whereas no obvious cell apoptosis of donor lung was noted in group B. After perfusion for 4 h, the levels of monocyte chemoattractant protein (MCP)-1 and IL-6 were significantly increased, the IL-4 levels were remarkably decreased (all P < 0.05), but the levels of tumor necrosis factor (TNF)-α, IL-1α and inducible nitric oxide synthase (iNOS) did not significantly change in both groups (all P > 0.05). Conclusions IL-10 may improve the function of donor lung after EVLP in rat of cardiac death by reducing cell apoptosis.

Progress in clinical application of urgent lung transplantation / 器官移植

Lung transplantation is the only effective treatment of end-stage lung diseases. Nevertheless, shortage of donor lungs has become increasingly prominent worldwide. A large quantity of patients died while waiting for lung transplantation. Urgent lung transplantation is a prioritized allocation strategy for donor lung transplantation according to the urgency of diseases, aiming to shorten the waiting time for donor lungs and reduce the fatality of patients on the waiting list for lung transplantation. However, no consensus has been reached worldwide on the definition, criteria and application of the terminology of urgent lung transplantation. In addition, the survival and net benefits of lung transplant recipients based on this allocation system are still controversial. On the basis of previous clinical research on urgent lung transplantation, the definition criteria, risk factors, survival outcomes, limitations and optimization measures were explicitly elucidated in this article, aiming to provide theoretical reference for comprehensive evaluation of the feasibility of urgent lung transplantation and further optimizing the allocation system of donor lungs.

Ex vivo lung perfusion for donor lung assessment and repair: a review of translational interspecies models.

For patients with end-stage lung disease, lung transplantation is a lifesaving therapy. Currently however, the number of patients who require a transplant exceeds the number of donor lungs available. One of the contributing factors to this is the conservative mindset of physicians who are concerned about transplanting marginal lungs due to the potential risk of primary graft dysfunction. Ex vivo lung perfusion (EVLP) technology has allowed for the expansion of donor pool of organs by enabling assessment and reconditioning of these marginal grafts before transplant. Ongoing efforts to optimize the therapeutic potential of EVLP are underway. Researchers have adopted the use of different large and small animal models to generate translational preclinical data. This includes the use of rejected human lungs, pig lungs, and rat lungs. In this review, we summarize some of the key current literature studies relevant to each of the major EVLP model platforms and identify the advantages and disadvantages of each platform. The review aims to guide investigators in choosing an appropriate species model to suit their specific goals of study, and ultimately aid in translation of therapy to meet the growing needs of the patient population.