HLA (HLA) are a major barrier to transplant success, as HLA-A and -B molecules are principal ligands for T-cells, and HLA-C for Killer cell Immunoglobulin-like Receptors (KIR), directing Natural Killer (NK) cell function. HLA-C molecules are designated \"C1\" or \"C2\" ligands based on residues 77 and 80, which determine the NK cell responses. Here, we investigated donor/recipient HLA-C mismatch associations with the development of chronic lung allograft dysfunction (CLAD) following lung transplantation (LTx). 310 LTx donor/recipient pairs were Next Generation Sequenced and assessed for C1 and C2 allotypes. PIRCHE scores were used to quantify HLA mismatching between donor/recipients at amino acid level and stratify recipients into low, moderate or highly mismatched groups (n = 103-104). Associations between C ligands and freedom from CLAD was assessed with Cox regression models and survival curves. C2/C2 recipients (n = 42) had less CLAD than those with C1/C1 (n = 138) or C1/C2 genotypes (n = 130) (p < 0.05). Incidence of CLAD was lower in C2/C2 recipients receiving a mismatched C1/C1 allograft (n = 14), compared to matched (n = 8) or heterozygous (n = 20) allografts. Furthermore, ~80% of these recipients (C2/C2 recipients receiving C1/C1 transplants) remained CLAD-free for 10 years post-LTx. Recipients with higher HLA-C mismatching had less CLAD (p < 0.05) an observation not explained by linkage disequilibrium with other HLA loci. Our data implicates a role for HLA-C in CLAD development. HLA-C mismatching was not detrimental to LTx outcome, but potentially beneficial, representing a paradigm shift in assessing donor/recipient matching. This may inform better selection of donor/recipient pairs and potentially more targeted approaches to treating CLAD.

BACKGROUND: The United Network for Organ Sharing (UNOS) started recording data on intellectual disability status in 2008. This study aimed to characterize the long-term outcomes for children with intellectual disabilities (IDs) undergoing lung transplantation.
METHODS: All pediatric patients (under 18 years old) undergoing bilateral lung transplantation were identified using the UNOS database. The patients were grouped into the following categories: no cognitive delay, possible cognitive delay, and definite cognitive delay. The primary endpoint was graft survival at 3-year posttransplantation. Multivariate Cox proportional hazards modeling was used to estimate the independent effect of cognitive disability on graft survival.
RESULTS: Five hundred four pediatric patients who underwent lung transplantation between March 2008 and December 2022 were retrospectively analyzed. 59 had a definite cognitive delay (12%), 23 had a possible delay (5%), and 421 had no delay (83%). When comparing these three groups, there was no significant difference in 60-day graft survival (p = 0.4), 3-year graft survival (p = 0.6), 3-year graft survival for patients who survived at least 60-day posttransplantation (p = 0.9), distribution of causes of death (p = 0.24), nor distribution treatment of rejection within 1-year posttransplantation (p = 0.06).
CONCLUSIONS: Intellectual disability does not impact long-term outcomes after bilateral lung transplantation. Intellectual disability should not be a contraindication to bilateral lung transplantation on the basis of inferior graft survival.

OBJECTIVE: Aspergillosis is the most common invasive fungal infection among lung transplant recipients (LTRs). Although its incidence is lower than that of bacterial or viral infections, it poses a similar or even higher mortality rate due to challenges in early diagnosis, limited treatment options, and various complications. Therefore, we aimed to evaluate the pulmonary aspergillosis cases in our tertiary lung transplant center.
METHODS: A retrospective analysis of 146 LTRs was performed. The demographic data, microbiological and histopathological test results, and radiological findings used for Aspergillus identification were recorded.
RESULTS: Aspergillus spp. was detected in 13 of 146 LTRs (9%), mean age 42.5 ± 14.06 years, an average of 18.9 months after lung transplantation. 3 cases (23%) had Aspergillus growth in tissue culture, and 2 (15.4%) showed fungal elements with septal hyaline fibrils in tissue pathology. Aspergillus spp Polymerase chain reaction (PCR) was positive in bronchoalveolar lavage of 8 (61.5%) cases. In addition, 4 (30.7%) cases had relevant tomography findings. The most common pathogens were A. Terreus (21%), A. Fumigatus (14%), and A. Flavus (14%). The mortality rate was 15%.
CONCLUSIONS: LTRs are at high risk of Aspergillus spp infections. Early diagnosis with microbiological, histopathological, and radiological tests, in addition to well-established prevention strategies, prophylaxis, and treatment will provide a better survival rate for patients.

UNASSIGNED: Centralizing deceased organ donor management and organ recovery into donor care units (DCUs) may mitigate the critical organ shortage by positively impacting donation and recipient outcomes.
UNASSIGNED: To compare donation and lung transplant outcomes between 2 common DCU models: independent (outside of acute-care hospitals) and hospital-based.
UNASSIGNED: This is a retrospective cohort study of Organ Procurement and Transplantation Network deceased donor registry and lung transplant recipient files from 21 US donor service areas with an operating DCU. Characteristics and lung donation rates among deceased donors cared for in independent vs hospital-based DCUs were compared. Eligible participants included deceased organ donors (aged 16 years and older) after brain death, who underwent organ recovery procedures between April 26, 2017, and June 30, 2022, and patients who received lung transplants from those donors. Data analysis was conducted from May 2023 to March 2024.
UNASSIGNED: Organ recovery in an independent DCU (vs hospital-based DCU).
UNASSIGNED: The primary outcome was duration of transplanted lung survival (through December 31, 2023) among recipients of lung(s) transplanted from cohort donors. A Cox proportional hazards model stratified by transplant year and program, adjusting for donor and recipient characteristics was used to compare graft survival.
UNASSIGNED: Of 10 856 donors in the starting sample (mean [SD] age, 42.8 [15.2] years; 6625 male [61.0%] and 4231 female [39.0%]), 5149 (primary comparison group) underwent recovery procedures in DCUs including 1466 (28.4%) in 11 hospital-based DCUs and 3683 (71.5%) in 10 independent DCUs. Unadjusted lung donation rates were higher in DCUs than local hospitals, but lower in hospital-based vs independent DCUs (418 donors [28.5%] vs 1233 donors [33.5%]; P < .001). Among 1657 transplant recipients, 1250 (74.5%) received lung(s) from independent DCUs. Median (range) duration of follow-up after transplant was 734 (0-2292) days. Grafts recovered from independent DCUs had shorter restricted mean (SE) survival times than grafts from hospital-based DCUs (1548 [27] days vs 1665 [50] days; P = .04). After adjustment, graft failure remained higher among lungs recovered from independent DCUs than hospital-based DCUs (hazard ratio, 1.85; 95% CI, 1.28-2.65).
UNASSIGNED: In this retrospective analysis of national donor and transplant recipient data, although lung donation rates were higher from deceased organ donors after brain death cared for in independent DCUs, lungs recovered from donors in hospital-based DCUs survived longer. These findings suggest that further work is necessary to understand which factors (eg, donor transfer, management, or lung evaluation and acceptance practices) differ between DCU models and may contribute to these differences.

BACKGROUND: Pleuroparenchymal fibroelastosis (PPFE) has no currently available specific treatment. Benefits of lung transplantation (LT) for PPFE are poorly documented.
METHODS: We conducted a nation-wide multicentric retrospective study in patients who underwent lung or heart-lung transplantation for chronic end-stage lung disease secondary to PPFE between 2012 and 2022 in France.
RESULTS: Thirty-one patients were included. At transplantation, median age was 48 years [IQR 35 - 55]. 64.5% were women. Twenty-one (67.7%) had idiopathic PFFE. Sixteen (52%) had bilateral LT, 10 (32%) had single LT, 4 (13%) had lobar transplantation and one (3%) had heart-lung transplantation. Operative mortality was 3.2%. Early mortality (< 90 days or during the first hospitalization) was 32%. Eleven patients (35.5%) underwent reoperation for hemostasis. Eight (30.8%) experienced bronchial complications. Mechanical ventilation time was 10 days [IQR 2-55]. Length of stay in intensive care unit and hospital were 34 [IQR 18-73] and 64 [IQR 36-103] days, respectively. Median survival was 21 months. Post-transplant survival rates after 1, 2, and 5 years were 57.9%, 42.6% and 38.3% respectively. Low albuminemia (p=0.046), FVC (p=0.021), FEV1 (p=0.009) and high emergency lung transplantation (p=0.04) were associated with increased early mortality. Oversized graft tended to be correlated to a higher mortality (p=0.07).
CONCLUSIONS: LT for PPFE is associated with high post-operative morbi-mortality rates. Patients requiring high emergency lung transplantation with advanced disease, malnutrition, or critical clinical status experienced worse outcomes.
RESULTS:
UNASSIGNED: NCT05044390.

BACKGROUND: The age profile of organ donors and patients on lung transplantation (LT) waiting lists have changed over time. In Europe, the donor population has aged much more rapidly than the recipient population, making allocation decisions on lungs from older donors common. In this study we assessed the impact of donor and recipient age discrepancy on LT outcomes in the UK and France.
METHODS: A retrospective analysis of all adult single or bilateral LT in France and the UK between 2010 and 2021. Recipients were stratified into 3 age groups: young (≤ 30 years), middle-aged (30 to 60) and older (≥60). Their donors were also stratified into 2 groups <60, ≥ 60. Primary graft dysfunction (PGD) rates and recipient survival was compared between matched and mismatched donor and recipient age groups. Propensity matching was employed to minimize covariate imbalances and to improve the internal validity of our results.
RESULTS: Our study cohort was 4,696 lung transplant recipients (LTRs). In young and older LTRs, there was no significant difference in 1 and 5-years post-transplant survival dependent on the age category of the donor. Young LTRs who received older donor grafts had a higher risk of severe grade 3 PGD.
CONCLUSIONS: Our findings show that clinically usable organs from older donors can be utilized safely in LT, even for younger recipients. Further research is needed to assess if the higher rate of PGD3 associated with use of older donors has an effect on long-term outcomes.

BACKGROUND: Postoperative acute kidney injury (AKI) after lung transplantation (LTx) is an important factor affecting the short-term outcomes. The focus item of transplantation centers is how to improve the incidence of AKI through optimal management during the perioperative period.
OBJECTIVE: The purpose of the study is to investigate the influence of perioperative volume in the development of early AKI following LTx.
METHODS: The study involved patients who had undergone LTx between October 2018 to December 2021 at China-Japan Friendship Hospital in Beijing. The patients were monitored for AKI occurring within 72 hours after LTx, as well as the renal outcomes within 30 days. The perioperative volumes were compared and analyzed to determine the impact on various clinical outcomes.
RESULTS: 248 patients were enrolled in the study ultimately, with almost half of them (49.6 %) experiencing AKI. 48.8 % of AKI patients received continuous renal replacement therapy (CRRT), with 57.7 % recovered by the end of the 30-day follow-up period. A J-shaped relationship was demonstrated between perioperative volume and AKI incidence. Moreover, maintaining a positive fluid balance would increase the 30-day mortality and lead to poor renal outcomes.
CONCLUSIONS: Perioperative volume is an independent risk factor of early AKI after LTx. Positive fluid balance increases the risk of AKI, 30-day mortality, and adverse renal prognosis. The LTx recipients may benefit from a relatively restrict fluid strategy during and after the lung transplantation.

Pulmonary arteriovenous malformations (PAVMs) are vascular anomalies resulting in abnormal connections between pulmonary arteries and veins. In 80% of cases, PAVMs are present from birth, but clinical manifestations are rarely seen in childhood. These congenital malformations are typically associated with Hereditary Hemorrhagic Telangiectasia (HHT), a rare disease that affects 1 in 5000/8000 individuals. HHT disease is frequently caused by mutations in genes involved in the TGF-β pathway. However, approximately 15% of patients do not have a genetic diagnosis and, among the genetically diagnosed, more than 33% do not meet the Curaçao criteria. This makes clinical diagnosis even more challenging in the pediatric age group. Here, we introduce an 8-year-old patient bearing a severe phenotype of multiple diffuse PAVMs caused by an unknown mutation which ended in lung transplantation. Phenotypically, the case under study follows a molecular pattern which is HHT-like. Therefore, molecular- biological and cellular-functional analyses have been performed in primary endothelial cells (ECs) isolated from the explanted lung. The findings revealed a loss of functionality in lung endothelial tissue and a stimulation of endothelial-to-mesenchymal transition. Understanding the molecular basis of this transition could potentially offer new therapeutic strategies to delay lung transplantation in severe cases.

Until now, the ability to predict or retard immune-mediated rejection events after lung transplantation is still limited due to the lack of specific biomarkers. The pressing need remains to early diagnose or predict the onset of chronic lung allograft dysfunction (CLAD) and its differential phenotypes that is the leading cause of death. Omics technologies (mainly genomics, epigenomics, and transcriptomics) combined with advanced bioinformatic platforms are clarifying the key immune-related molecular routes that trigger early and late events of lung allograft rejection supporting the biomarker discovery. The most promising biomarkers came from genomics. Both unregistered and NIH-registered clinical trials demonstrated that the increased percentage of donor-derived cell-free DNA in both plasma and bronchoalveolar lavage fluid showed a good diagnostic performance for clinically silent acute rejection events and CLAD differential phenotypes. A further success arose from transcriptomics that led to development of Molecular Microscope® Diagnostic System (MMDx) to interpret the relationship between molecular signatures of lung biopsies and rejection events. Other immune-related biomarkers of rejection events may be exosomes, telomer length, DNA methylation, and histone-mediated neutrophil extracellular traps (NETs) but none of them entered in registered clinical trials. Here, we discuss novel and existing technologies for revealing new immune-mediated mechanisms underlying acute and chronic rejection events, with a particular focus on emerging biomarkers for improving precision medicine of lung transplantation field.

Brain death triggers a systemic inflammatory response. Whether systemic inflammation is different in lung donors after brain- (DBD) or circulatory-death (DCD) is unknown, but this may potentially increase the incidence of primary graft dysfunction (PGD) after lung transplantation. We compared the plasma levels of interleukin (IL)-6, IL-8, IL-10 and TNF-α in BDB and DCD and their respective recipients, as well as their relationship with PGD and mortality after LT. A prospective, observational, multicenter, comparative, cohort-nested study that included 40 DBD and 40 DCD lung donors matched and their respective recipients. Relevant clinical information and blood samples were collected before/during lung retrieval in donors and before/during/after (24, 48 and 72 h) LT in recipients. Incidence of PGD and short-term mortality after LT was recorded. Plasma levels of all determined cytokines were numerically higher in DBD than in DCD donors and reached statistical significance for IL-6, IL-10 and IL-8. In recipients with PGD the donor\'s plasma levels of TNF-α were higher. The post-operative mortality rate was very low and similar in both groups. DBD is associated with higher systemic inflammation than DCD donors, and higher TNF-α plasma levels in donors are associated with a higher incidence of PGD.