The nature of chronic rejection after lung transplantation: a murine orthotopic lung transplant study.

Introduction: Chronic rejection is a major complication post-transplantation. Within lung transplantation, chronic rejection was considered as airway centred. Chronic Lung Allograft Dysfunction (CLAD), defined to cover all late chronic complications, makes it more difficult to understand chronic rejection from an immunological perspective. This study investigated the true nature, timing and location of chronic rejection as a whole, within mouse lung transplantation. Methods: 40 mice underwent an orthotopic left lung transplantation, were sacrificed at day 70 and evaluated by histology and in vivo µCT. For timing and location of rejection, extra grafts were sacrificed at day 7, 35, 56 and investigated by ex vivo µCT or single cell RNA (scRNA) profiling. Results: Chronic rejection originated as innate inflammation around small arteries evolving toward adaptive organization with subsequent end-arterial fibrosis and obliterans. Subsequently, venous and pleural infiltration appeared, followed by airway related bronchiolar folding and rarely bronchiolitis obliterans was observed. Ex vivo µCT and scRNA profiling validated the time, location and sequence of events with endothelial destruction and activation as primary onset. Conclusion: Against the current belief, chronic rejection in lung transplantation may start as an arterial response, followed by responses in venules, pleura, and, only in the late stage, bronchioles, as may be seen in some but not all patients with CLAD.

Effect of epoprostenol-induced thrombocytopaenia on lung transplantation for pulmonary arterial hypertension.

OBJECTIVES: Preoperative intravenous epoprostenol therapy can cause thrombocytopaenia, which may increase the risk of perioperative bleeding during lung transplantation. This study aimed to determine whether lung transplantation can be safely performed in patients with epoprostenol-induced thrombocytopaenia. METHODS: From June 2008 to July 2022, we performed 37 lung transplants in patients with pulmonary arterial hypertension (PAH), including idiopathic PAH (n = 26), congenital heart disease-associated PAH (n = 7), pulmonary veno-occlusive disease (n = 3) and peripheral pulmonary artery stenosis (n = 1) at our institution. Of these, 26 patients received intravenous epoprostenol therapy (EPO group), whereas 11 patients were treated with no epoprostenol (no-EPO group). We retrospectively analysed the preoperative and postoperative platelet counts and post-transplant outcomes in each group. RESULTS: Preoperative platelet counts were relatively lower in the EPO group than in the no-EPO group (median EPO: 127 000 vs no-EPO: 176 000/µl). However, blood loss during surgery was similar between the 2 groups (EPO: 2473 ml vs no-EPO: 2615 ml). The platelet counts significantly increased over 1 month after surgery, and both groups showed similar platelet counts (EPO: 298 000 vs no-EPO: 284 000/µl). In-hospital mortality (EPO: 3.9% vs no-EPO: 18.2%) and the 3-year survival rate (EPO: 91.4% vs no-EPO: 80.8%) were similar between the 2 groups. CONCLUSIONS: Patients with PAH treated with intravenous epoprostenol showed relatively lower platelet counts, which improved after lung transplantation with good post-transplant outcomes.

Fibrotic progression from acute cellular rejection is dependent on secondary lymphoid organs in a mouse model of chronic lung allograft dysfunction.

Chronic lung allograft dysfunction (CLAD) remains one of the major limitations to long-term survival after lung transplantation. We modified a murine model of CLAD and transplanted left lungs from BALB/c donors into B6 recipients that were treated with intermittent cyclosporine and methylprednisolone postoperatively. In this model, the lung allograft developed acute cellular rejection on day 15 which, by day 30 after transplantation, progressed to severe pleural and peribronchovascular fibrosis, reminiscent of changes observed in restrictive allograft syndrome. Lung transplantation into splenectomized B6 alymphoplastic (aly/aly) or splenectomized B6 lymphotoxin-ß receptor-deficient mice demonstrated that recipient secondary lymphoid organs, such as spleen and lymph nodes, are necessary for progression from acute cellular rejection to allograft fibrosis in this model. Our work uncovered a critical role for recipient secondary lymphoid organs in the development of CLAD after pulmonary transplantation and may provide mechanistic insights into the pathogenesis of this complication.

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.

Favorable effect of CD26/DPP-4 inhibitors on postoperative outcomes after lung transplantation: A propensity-weighted analysis.

BACKGROUND: We have shown the efficacy of CD26/dipeptidyl peptidase 4 (CD26/DPP-4) inhibitors, antidiabetic agents, in allograft protection after experimental lung transplantation (LTx). We aimed to elucidate whether CD26/DPP-4 inhibitors effectively improve postoperative outcomes after clinical LTx. METHODS: We retrospectively reviewed the records of patients undergoing LTx at our institution between 2010 and 2021 and extracted records of patients with diabetes mellitus (DM) at 6 months post-LTx. The patient characteristics and postoperative outcomes were analyzed. We established 6 months post-LTx as the landmark point for predicting overall survival (OS) and chronic lung allograft dysfunction (CLAD)-free survival. Hazard ratios were estimated by Cox regression after propensity score weighting, using CD26/DPP-4 inhibitor treatment up to 6 months post-LTx as the exposure variable. We evaluated CLAD samples pathologically, including for CD26/DPP-4 immunohistochemistry. RESULTS: Of 102 LTx patients with DM, 29 and 73 were treated with and without CD26/DPP-4 inhibitors, respectively. Based on propensity score adjustment using standardized mortality ratio weighting, the 5-year OS rates were 77.0% and 44.3%, and the 5-year CLAD-free survival rates 77.8% and 49.1%, in patients treated with and without CD26/DPP-4 inhibitors, respectively. The hazard ratio for CD26/DPP-4 inhibitor use was 0.34 (95% confidence interval (CI) 0.14-0.82, p = 0.017) for OS and 0.47 (95% CI 0.22-1.01, p = 0.054) for CLAD-free survival. We detected CD26/DPP-4 expression in the CLAD grafts of patients without CD26/DPP-4 inhibitors. CONCLUSIONS: Analysis using propensity score weighting showed that CD26/DPP-4 inhibitors positively affected the postoperative prognosis of LTx patients with DM.

Impact of perioperative airway pathogens on living-donor lobar lung transplantation outcomes.

PURPOSE: To elucidate the clinical impact of pathogenic organism (PO) positivity early after transplantation, we evaluated the impact of perioperative airway POs on outcomes after living-donor lobar lung transplantation (LDLLT), where the graft airway is supposed to be sterile from a healthy donor. METHOD: A retrospective review of 67 adult LDLLT procedures involving 132 living donors was performed. Presence of POs in the recipients' airways was evaluated preoperatively and postoperatively in intensive-care units. RESULTS: POs were detected preoperatively in 13 (19.4%) recipients. No POs were isolated from the donor airways at transplantation. POs were detected in 39 (58.2%) recipients postoperatively; most were different from the POs isolated preoperatively. Postoperative PO isolation was not associated with short-term outcomes other than prolonged postoperative ventilation. The 5-year overall survival was significantly better in the PO-negative group than in the PO-positive group (89.1% vs. 63.7%, P = 0.014). In the multivariate analysis, advanced age (hazard ratio [HR]: 1.041 per 1-year increase, P = 0.033) and posttransplant PO positivity in the airway (HR: 3.684, P = 0.019) significantly affected the survival. CONCLUSIONS: The airways of the living-donor grafts were microbiologically sterile. PO positivity in the airway early after transplantation negatively impacted long-term outcomes.

Evaluation of Bone Mineral Density in Lung Transplant Recipients by Chest Computed Tomography.

INTRODUCTION: Lung transplantation (LT) recipients are at risk of bone mineral density (BMD) loss. Pre- and post-LT BMD loss has been reported in some cross-sectional studies; however, there are limited studies regarding the serial BMD change in LT recipients. The aim of this study was to investigate the serial BMD changes and the clinical characteristics associated with BMD decline. METHODS: This was a single-center, retrospective observational study. BMD was serially measured in thoracic vertebral bodies (Th4, 7, 10) using computed tomography (CT) before and 3 and 12 months after LT. The frequency of osteoporosis and factors associated with pre-LT osteoporosis and post-LT BMD loss were evaluated. The frequency of post-LT compression fracture and its associated factors were also analyzed. RESULTS: This study included 128 adult LT recipients. LT recipients had decreased BMD (151.8 ± 42.2 mg/mL) before LT compared with age-, sex-, and smoking index-matched controls (176.2 ± 35.7 mg/mL). The diagnosis of COPD was associated with pre-LT osteoporosis. LT recipients experience further BMD decline after transplantation, and the percentage of recipients classified as exhibiting osteoporosis increased from 20% at baseline to 43% at 12 months. Recipients who had been taking no or small doses of glucocorticoids before LT had rapid BMD loss after LT. Early bisphosphonate use (within 3 months) after LT attenuated BMD loss and decreased new-onset compression fracture. CONCLUSION: LT recipients are at high risk for BMD loss and compression fracture after LT. Early bisphosphonate use may decrease BMD loss and compression fracture.

Protocol for orthotopic single-lung transplantation in mice as a tool for lung metastasis studies.

The transplantation model provides the opportunity to assess the relevance of a molecule of interest for tumor cell extravasation by using a respective genetically modified donor animal. Here, we present a protocol for orthotopic single-lung transplantation in mice as a tool for lung metastasis studies. We describe steps for animal preparation, lung transplantation, and tumor cell injection. We then detail procedures for the direct comparison of tumor cell spreading between the genetically modified left lung and the naive right lung parenchyma. For complete details on the use and execution of this protocol, please refer to Giannou et al. (2023).1.

Novel intrathoracic irrigation using ultrafine ozone bubbles in a rat empyema model.

Dissolved ozone is generally used for sanitization, but it has not been used for thoracic cavity sanitization because of its short half-life (< 20 min) and possible toxicity. We developed a novel solution containing ultrafine ozone bubbles (ozone-UFB) with a fivefold longer half-life than non-UFB ozone. Using an in vitro model, Staphylococcus aureus colonies were counted after exposure to ozone-UFB or non-UFB ozone at the same ozone concentration (0.4 mg/L). The colony count was significantly lower in the ozone-UFB group than in the non-UFB ozone group (p = 0.034). The effect of repeated pleural irrigation using ozone-UFB and saline was compared in a rat empyema model of S. aureus infection. The bacterial count in the pleural effusion was decreased by at least fivefold following intrathoracic lavage with ozone-UFB (3 mg/L). To examine the safety of ozone-UFB for intrathoracic use, ozone-UFB with a higher ozone concentration (10 mg/L) was injected into the thoracic cavities of normal rats. The treatment did not result in any specific pleural damage or elevated serum interleukin-6 concentrations. The findings highlighted the efficacy and safety of ozone-UFB for intrathoracic sanitization, but further studies are needed to determine the optimal therapeutic ozone concentration with appropriate safety margins.

M2-like tumor-associated macrophages promote epithelial-mesenchymal transition through the transforming growth factor ß/Smad/zinc finger e-box binding homeobox pathway with increased metastatic potential and tumor cell proliferation in lung squamous cell carcinoma.

Epithelial-mesenchymal transition (EMT) promotes primary tumor progression toward a metastatic state. The role of tumor-associated macrophages (TAMs) in inducing EMT in lung squamous cell carcinoma (LUSC) remains unclear. We aimed to clarify the significance of TAMs in relation to EMT in LUSC. We collected 221 LUSC specimens from patients who had undergone surgery. Immunohistochemistry was performed to evaluate M1-like and M2-like TAM distribution and EMT by E-cadherin and vimentin staining. Human LUSC cell lines (H226 and EBC-1) and a human monocyte cell line (THP-1) were used for in vitro experiments. M2-like polarization of TAMs and EMT marker expression in LUSC cells were evaluated by western blotting. The biological behavior of LUSC cells was evaluated by migration, invasion, and cell proliferation assays. Immunohistochemical analysis showed that 166 (75.1%) tumors were E-cadherin-positive and 44 (19.9%) were vimentin-positive. M2-like TAM density in the tumor stroma was significantly associated with vimentin positivity and worse overall survival. Western blotting demonstrated higher levels of CD163, CD206, vascular endothelial growth factor, and transforming growth factor beta 1 (TGF-ß1) in TAMs versus unstimulated macrophages. Furthermore, increased TGF-ß1 secretion from TAMs was confirmed by ELISA. TAM-co-cultured H226 and EBC-1 cells exhibited EMT (decreased E-cadherin, increased vimentin). Regarding EMT-activating transcriptional factors, phosphorylated Smad3 and ZEB-family proteins were higher in TAM-co-cultured LUSC cells than in parental cells. TAM-co-cultured H226 and EBC-1 cells demonstrated enhanced migration and invasion capabilities and improved proliferation. Overall, the present study suggests that TAMs can induce EMT with increased metastatic potential and tumor cell proliferation in LUSC.

Prognosis of patients with systemic sclerosis-related interstitial lung disease on the lung transplant waiting list: a retrospective study.

Advanced systemic sclerosis-associated interstitial lung disease (SSc-ILD) can be treated with lung transplantation. There is limited data on lung transplantation outcomes in patients with SSc-ILD, in non-Western populations.We assessed survival data of patients with SSc-ILD, on the lung transplant (LT) waiting list, and evaluated post-transplant outcomes in patients from an Asian LT center. In this single-center retrospective study, 29 patients with SSc-ILD, registered for deceased LT at Kyoto University Hospital, between 2010 and 2022, were identified. We investigated post-transplant outcomes in recipients who underwent LT for SSc-ILD, between February 2002 and April 2022. Ten patients received deceased-donor LT (34%), two received living-donor LT (7%), seven died waiting for LT (24%), and ten survived on the waiting list (34%). Median duration from registration to deceased-donor LT was 28.9 months and that from registration to living-donor LT or death was 6.5 months. Analysis of 15 recipients showed improved forced vital capacity with a median of 55.1% at baseline, 65.8% at 6 months, and 80.3% at 12 months post-transplant. The 5-year survival rate for post-transplant patients with SSc-ILD was 86.2%. The higher post-transplant survival rate at our institute than previously reported suggests that lung transplantation is acceptable in Asian patients with SSc-ILD.

One-year change in the health status predicts the subsequent hospitalization and mortality in patients waitlisted for lung transplantation in Japan.

BACKGROUND: Poor health-related quality of life (HRQL) at the registration for lung transplantation is related to waitlist mortality. We investigated the relationship between 1-year change in HRQL and subsequent outcomes in patients waitlisted for lung transplantation. METHODS: In a 5-year longitudinal study, we analyzed the factors related to waitlist mortality in 197 lung transplant patients registered on the Japan Organ Transplant Network. HRQL was assessed using St. George's Respiratory Questionnaire (SGRQ), and factors related to changes in SGRQ scores were evaluated after 1 year. We assessed the relationship between the 1-year change in SGRQ score and subsequent mortality or hospitalization. RESULTS: Among 197 patients, 108 remained waitlisted during the first-year assessment. During the median follow-up period of 469 d, 28 patients died, and 54 underwent lung transplantation. Univariate Cox proportional hazards analysis revealed that the changes in all components and total score of the SGRQ after 1 year were associated with waitlist mortality (p < 0.05). Stepwise multivariate analysis revealed that the 1-year changes in SGRQ scores were significantly related to waitlist mortality. Forty-three patients with worsened HRQL after 1 year had higher likelihoods of hospitalization (p = 0.038) and mortality (p = 0.026) after 1 and 4 years of follow-up, respectively, than 61 patients without worsened HRQL. CONCLUSIONS: Patients with worsened health status during the first year after registration had higher likelihoods of hospitalization and mortality after 1 and 4 years of follow-up, respectively, than those without worsened HRQL. Strategies to improve health status while waiting are needed to reduce waitlist hospitalization or mortality.

The first successful case of ABO-incompatible living-donor lobar lung transplantation following desensitization therapy.

ABO-incompatible (ABO-I) living-donor lobar lung transplantation (LDLLT) was successfully performed in a 14-year-old girl who suffered from bronchiolitis obliterans due to graft-versus-host disease following hematopoietic stem cell transplantation. In the ABO-I LDLLT procedure, the blood type O patient received a right lower lobe donated from her blood type B father and a left lower lobe donated from her blood type O mother. Desensitization therapy, using rituximab, immunosuppressants, and plasmapheresis, was implemented for 3 weeks prior to transplantation to reduce the production of anti-B antibodies in the recipient and prevent acute antibody-mediated rejection after ABO-I LDLLT.

Impact of Spousal Donation on Postoperative Outcomes of Living-donor Lobar Lung Transplantation.

BACKGROUND: The effect of human leukocyte antigen mismatches between donors and recipients on postoperative outcomes of lung transplantation remains controversial. We retrospectively reviewed adult recipients receiving living-donor lobar lung transplantation (LDLLT) to examine the difference in de novo donor-specific antibody (dnDSA) development and clinically diagnosed unilateral chronic lung allograft dysfunction per graft (unilateral CLAD) between lung grafts donated by spouses (nonblood relatives) and nonspouses (relatives within the third degree). We also investigated the difference in prognoses between recipients undergoing LDLLTs including spouse donors (spousal LDLLTs) and not including spouse donors (nonspousal LDLLTs). METHODS: In this study, 63 adult recipients undergoing LDLLTs (61 bilateral and 2 unilateral LDLLTs from 124 living donors) between 2008 and 2020 were enrolled. The cumulative incidence of dnDSAs per lung graft was calculated, and prognoses were compared between recipients undergoing spousal and nonspousal LDLLTs. RESULTS: The cumulative incidence of both dnDSAs and unilateral CLAD in grafts donated by spouses was significantly higher than that in grafts donated by nonspouses (5-y incidence of dnDSAs: 18.7% versus 6.4%, P = 0.038; 5-y incidence of unilateral CLAD: 45.6% versus 19.4%, P = 0.011). However, there were no significant differences in the overall survival or chronic lung allograft dysfunction-free survival between recipients undergoing spousal and nonspousal LDLLTs ( P > 0.99 and P = 0.434, respectively). CONCLUSIONS: Although there were no significant differences in prognoses between spousal and nonspousal LDLLTs, more attention should be paid to spousal LDLLTs because of the higher development rate of dnDSAs and unilateral CLAD.

Biased IL-2 signals induce Foxp3-rich pulmonary lymphoid structures and facilitate long-term lung allograft acceptance in mice.

Transplantation of solid organs can be life-saving in patients with end-stage organ failure, however, graft rejection remains a major challenge. In this study, by pre-conditioning with interleukin-2 (IL-2)/anti-IL-2 antibody complex treatment biased toward IL-2 receptor α, we achieved acceptance of fully mismatched orthotopic lung allografts that remained morphologically and functionally intact for more than 90 days in immunocompetent mice. These allografts are tolerated by the actions of forkhead box p3 (Foxp3)+ regulatory T (Treg) cells that home to the lung allografts. Although counts of circulating Treg cells rapidly return to baseline following cessation of IL-2 treatment, Foxp3+ Treg cells persist in peribronchial and peribronchiolar areas of the grafted lungs, forming organized clusters reminiscent of inducible tertiary lymphoid structures (iTLS). These iTLS in lung allografts are made of Foxp3+ Treg cells, conventional T cells, and B cells, as evidenced by using microscopy-based distribution and neighborhood analyses. Foxp3-transgenic mice with inducible and selective deletion of Foxp3+ cells are unable to form iTLS in lung allografts, and these mice acutely reject lung allografts. Collectively, we report that short-term, high-intensity and biased IL-2 pre-conditioning facilitates acceptance of vascularized and ventilated lung allografts without the need of immunosuppression, by inducing Foxp3-controlled iTLS formation within allografts.

Comparison of living-donor lobar lung transplantation and cadaveric lung transplantation for pulmonary hypertension.

OBJECTIVES: Living-donor lobar lung transplantation (LDLLT) is a life-saving procedure for critically ill patients with various lung diseases, including pulmonary hypertension (PH). However, there are concerns regarding the development of heart failure with pulmonary oedema after LDLLT in which only 1 or 2 lobes are implanted. This study aimed to compare the preoperative conditions and postoperative outcomes of LDLLT with those of cadaveric lung transplantation (CLT) in PH patients. METHODS: Between 2008 and 2021, 34 lung transplants for PH, including 12 LDLLTs (5 single and 7 bilateral) and 22 bilateral CLTs, were performed. Preoperative variables and postoperative outcomes were retrospectively compared between the 2 procedures. RESULTS: Based on the preoperative variables of less ambulatory ability (41.7% vs 100%, P < 0.001), a higher proportion of World Health Organization class 4 (83.3% vs 18.2%, P < 0.001) and higher mean pulmonary artery pressure (74.4 vs 57.3 mmHg, P = 0.040), LDLLT patients were more debilitated than CLT patients. Nevertheless, hospital death was similar between the 2 groups (8.3% vs 9.1%, P > 0.99, respectively). Furthermore, the 5-year overall survival rate was similar between the 2 groups (90.0% vs 76.3%, P = 0.489). CONCLUSIONS: Although LDLLT patients with PH had worse preoperative conditions and received smaller grafts than CLT patients, LDLLT patients demonstrated similar perioperative outcomes and prognoses as CLT patients. LDLLT is a viable treatment option for patients with PH.

Tissue resident iNKT17 cells facilitate cancer cell extravasation in liver metastasis via interleukin-22.

During metastasis, cancer cells invade, intravasate, enter the circulation, extravasate, and colonize target organs. Here, we examined the role of interleukin (IL)-22 in metastasis. Immune cell-derived IL-22 acts on epithelial tissues, promoting regeneration and healing upon tissue damage, but it is also associated with malignancy. Il22-deficient mice and mice treated with an IL-22 antibody were protected from colon-cancer-derived liver and lung metastasis formation, while overexpression of IL-22 promoted metastasis. Mechanistically, IL-22 acted on endothelial cells, promoting endothelial permeability and cancer cell transmigration via induction of endothelial aminopeptidase N. Multi-parameter flow cytometry and single-cell sequencing of immune cells isolated during cancer cell extravasation into the liver revealed iNKT17 cells as source of IL-22. iNKT-cell-deficient mice exhibited reduced metastases, which was reversed by injection of wild type, but not Il22-deficient, invariant natural killer T (iNKT) cells. IL-22-producing iNKT cells promoting metastasis were tissue resident, as demonstrated by parabiosis. Thus, IL-22 may present a therapeutic target for prevention of metastasis.

A novel cell-based assay for the high-throughput screening of epithelial-mesenchymal transition inhibitors: Identification of approved and investigational drugs that inhibit epithelial-mesenchymal transition.

OBJECTIVES: Lung cancer with distant metastases is associated with a very poor prognosis, and epithelial-mesenchymal transition (EMT) contributes to cancer metastasis. Therefore, elucidation and inhibition of EMT signaling in lung cancer may be a new therapeutic strategy for improving the prognosis of patients. We constructed a high-throughput screening system for EMT inhibitors. Using this system, we aimed to identify compounds that indeed inhibit EMT. MATERIALS AND METHODS: We generated a luciferase reporter cell line using A549 human lung cancer cells and E-cadherin or vimentin as EMT markers. EMT was induced by transforming growth factor ß1 (TGF-ß1), and candidate EMT inhibitors were screened from a library of 2,350 compounds. The selected compounds were further tested using secondary assays to verify the inhibition of EMT and invasive capacity of cells. RESULTS: Values obtained by the assay were adjusted for the number of viable cells and scored by determining the difference between mean values of the positive and negative control groups. Four compounds were identified as novel candidate drugs. Among those, one (avagacestat) and two compounds (GDC-0879 and levothyroxine) improved the expression of E-cadherin and vimentin, respectively, in epithelial cells. GDC-0879 and levothyroxine also significantly inhibited the invasive capacity of cells. CONCLUSION: We systematically screened approved, investigational, and druggable compounds with inhibitory effects using a reporter assay, and identified candidate drugs for EMT inhibition.

Outcome and growth of lobar graft after pediatric living-donor lobar lung transplantation.

BACKGROUND: Living-donor lobar lung transplantation (LDLLT) remains a life-saving option for pediatric patients with respiratory failure. However, the long-term survival and post-transplant quality of adult lobar grafts transplanted into children are unknown. Therefore, this study aimed to evaluate the outcomes of pediatric LDLLT and post-transplant graft growth. METHODS: We retrospectively reviewed the prospectively collected clinical data of 25 living-donor lung transplantations performed in 24 pediatric recipients aged ≤17 years. The annual pulmonary function test data and computed tomography scans of 12 recipients, followed up for >5 years without significant complications, were used to evaluate growth in height, graft function, and radiological changes. The Kaplan-Meier method and simple linear regression were performed for analysis. RESULTS: Bilateral lower lobe transplantation was performed in 12 patients, unilateral lower lobe transplantation in 12, and bilateral middle lobe transplantation in 1. The median volumetric size matching at transplantation was 142% (range, 54%-457%). The 5- and 10-year overall survival rates were 87.7% and 75.1༅, respectively. Chronic lung allograft dysfunction occurred in 2 patients. During a median follow-up of 6 years, the median increases in height and vital capacity were 14.4% (range, 0.80%-43.5%) and 58.5% (range, 6.7%-322%), respectively. Graft weight was positively correlated with graft volume (r2=0.622, p<0.001) after the graft volume exceeded the original lobar volume in the donor. CONCLUSIONS: This study shows that pediatric LDLLT offers satisfactory long-term survival, with the growth of mature adult lobes transplanted into growing children.

Reduction of donor mononuclear phagocytes with clodronate-liposome during ex vivo lung perfusion attenuates ischemia-reperfusion injury.

OBJECTIVES: Clodronate-liposome is used for depleting mononuclear phagocytes associated with ischemia-reperfusion injury. We hypothesized that administration of clodronate-liposome into the perfusate during ex vivo lung perfusion could reduce mononuclear phagocytes and attenuate ischemia-reperfusion injury. METHODS: First, the number of mononuclear phagocytes in flushed grafts (minimum cold ischemic time, 6-hour cold ischemic time, 15-hour cold ischemic time, and 18-hour cold ischemic time; n = 6 each) was determined using flow cytometry. Second, grafts (15-hour cold ischemic time) were allocated to control or clodronate (n = 5 each). In the clodronate group, clodronate-liposome is administered into the perfusate. After 4 hours of ex vivo lung perfusion, the number of mononuclear phagocytes in the perfusate and lung tissues was measured. Third, grafts (15-hour cold ischemic time) were allocated to control or clodronate (n = 6 each). After 4 hours of ex vivo lung perfusion, the left lungs were transplanted and reperfused for 2 hours. Lung function was evaluated, and samples were analyzed. RESULTS: First, mononuclear phagocytes remain in flushed grafts after prolonged cold ischemia. Second, the number of mononuclear phagocytes in lung tissues after ex vivo lung perfusion was significantly reduced in the clodronate group (P = .008). Third, lung compliance and vascular resistance during ex vivo lung perfusion were significantly improved in the clodronate group (P < .001 for both). Blood oxygenation and pulmonary edema were significantly improved in the clodronate group after 2 hours of reperfusion (P = .015 and P = .026, respectively). Histological findings showed reduced lung injury in the clodronate group (P = .013). CONCLUSIONS: Administration of clodronate-liposome into the perfusate during ex vivo lung perfusion resulted in a significant reduction of mononuclear phagocytes in donor lungs, leading to attenuation of ischemia-reperfusion injury.