Multi-Locus Microsatellite Typing of Colonising and Invasive Aspergillus fumigatus Isolates from Patients Post Lung Transplantation and with Chronic Lung Disease.

Aspergillus fumigatus can cause different clinical manifestations/phenotypes in lung transplant (LTx) recipients and patients with chronic respiratory diseases. It can also precipitate chronic lung allograft dysfunction (CLAD) in LTx recipients. Many host factors have been linked with the severity of A. fumigatus infection, but little is known about the contribution of different A. fumigatus strains to the development of different phenotypes and CLAD. We used multi-locus microsatellite typing (MLMT) to determine if there is a relationship between strain (i.e., genotype) and phenotype in 60 patients post LTx or with chronic respiratory disease across two time periods (1 November 2006-31 March 2009 and 1 November 2015-30 June 2017). The MLMT (STRAf) assay was highly discriminatory (Simpson's diversity index of 0.9819-0.9942) with no dominant strain detected. No specific genotype-phenotype link was detected, but several clusters and related strains were associated with invasive aspergillosis (IA) and colonisation in the absence of CLAD. Host factors were linked to clinical phenotypes, with prior lymphopenia significantly more common in IA cases as compared with A. fumigatus-colonised patients (12/16 [75%] vs. 13/36 [36.1%]; p = 0.01), and prior Staphylococcus aureus infection was a significant risk factor for the development of IA (odds ratio 13.8; 95% confidence interval [2.01-279.23]). A trend toward a greater incidence of CMV reactivation post-A. fumigatus isolation was observed (0 vs. 5; p = 0.06) in LTx recipients. Further research is required to determine the pathogenicity and immunogenicity of specific A. fumigatus strains.

Examining the impact of immunosuppressive drugs on antibody-dependent cellular cytotoxicity (ADCC) of human peripheral blood natural killer (NK) cells and gamma delta (γδ) T cells.

BACKGROUND: Human natural killer (NK) cells and gamma delta (γδ) T cells may impact outcomes of solid organ transplantation (SOT) such as lung transplantation (LTx) following the differential engagement of an array of activating and inhibitory receptors. Amongst these, CD16 may be particularly important due to its capacity to bind IgG to trigger antibody-dependent cellular cytotoxicity (ADCC) and the production of proinflammatory cytokines. While the use of immunosuppressive drugs (ISDs) is an integral component of SOT practice, their relative impact on various immune cells, especially γδT cells and CD16-induced functional responses, is still unclear. METHODS: The ADCC responses of peripheral blood NK cells and γδT cells from both healthy blood donors and adult lung transplant recipients (LTRs) were assessed by flow cytometry. Specifically, the degranulation response, as reflected in the expression of CD107a, and the capacity of both NK cells and γδT cells to produce IFN-γ and TNF-α was assessed following rituximab (RTX)-induced activation. Additionally, the effect of cyclosporine A (CsA), tacrolimus (TAC), prednisolone (Prdl) and azathioprine (AZA) at the concentration of 1 ng/ml, 10 ng/ml, 100 ng/ml, and 1000 ng/ml on these responses was also compared in both cell types. RESULTS: Flow cytometric analyses of CD16 expresion showed that its expression on γδT cells was both at lower levels and more variable than that on peripheral blood NK cells. Nevertheless functional analyses showed that despite these differences, γδT cells like NK cells can be readily activated by engagement with RTX to degranulate and produce cytokines such as IFNg and TNF-a. RTX-induced degranulation by either NK cells or γδT cells from healthy donors was not impacted by co-culture with individual ISDs. However, CsA and TAC but not Prdl and AZA did inhibit the production of IFN-γ and TNF-α by both cell types. Flow cytometric analyses of RTX-induced activation of NK cells and γδT cells from LTRs suggested their capacity to degranulate was not markedly impacted by transplantation with similar levels of cells expressing CD107 pre- and post-LTx. However an impairment in the ability of NK cells to produce cytokines was observed in samples obtained post LTx whereas γδT cell cytokine responses were not significantly impacted. CONCLUSIONS: In conclusion, the findings show that despite differences in the expression levels of CD16, γδT cells like NK cells can be readily activated by engagement with RTX and that in vitro exposure to CsA and TAC (calcineurin inhibitors) had a measurable effect on cytokine production but not degranulation by both NK cells and gdT cells from healthy donors. Finally the observation that in PBMC obtained from LTx recipients, NK cells but not γδT cells exhibited impaired cytokine reponses suggests that transplantation or chronic exposure to ISDs differentially impacts their potential to respond to the introduction of an allograft and/or transplant-associated infections.

Defining a natural killer cell-enriched molecular rejection-like state in lung transplant transbronchial biopsies.

In lung transplantation, antibody-mediated rejection (AMR) diagnosed using the International Society for Heart and Lung Transplantation criteria is uncommon compared with other organs, and previous studies failed to find molecular AMR (ABMR) in lung biopsies. However, understanding of ABMR has changed with the recognition that ABMR in kidney transplants is often donor-specific antibody (DSA)-negative and associated with natural killer (NK) cell transcripts. We therefore searched for a similar molecular ABMR-like state in transbronchial biopsies using gene expression microarray results from the INTERLUNG study (#NCT02812290). After optimizing rejection-selective transcript sets in a training set (N = 488), the resulting algorithms separated an NK cell-enriched molecular rejection-like state (NKRL) from T cell-mediated rejection (TCMR)/Mixed in a test set (N = 488). Applying this approach to all 896 transbronchial biopsies distinguished 3 groups: no rejection, TCMR/Mixed, and NKRL. Like TCMR/Mixed, NKRL had increased expression of all-rejection transcripts, but NKRL had increased expression of NK cell transcripts, whereas TCMR/Mixed had increased effector T cell and activated macrophage transcripts. NKRL was usually DSA-negative and not recognized as AMR clinically. TCMR/Mixed was associated with chronic lung allograft dysfunction, reduced one-second forced expiratory volume at the time of biopsy, and short-term graft failure, but NKRL was not. Thus, some lung transplants manifest a molecular state similar to DSA-negative ABMR in kidney and heart transplants, but its clinical significance must be established.

Angiotensin-Converting Enzyme 2 (ACE2), Transmembrane Peptidase Serine 2 (TMPRSS2), and Furin Expression Increases in the Lungs of Patients with Idiopathic Pulmonary Fibrosis (IPF) and Lymphangioleiomyomatosis (LAM): Implications for SARS-CoV-2 (COVID-19) Infections.

We previously reported higher ACE2 levels in smokers and patients with COPD. The current study investigates if patients with interstitial lung diseases (ILDs) such as IPF and LAM have elevated ACE2, TMPRSS2, and Furin levels, increasing their risk for SARS-CoV-2 infection and development of COVID-19. Surgically resected lung tissue from IPF, LAM patients, and healthy controls (HC) was immunostained for ACE2, TMPRSS2, and Furin. Percentage ACE2, TMPRSS2, and Furin expression was measured in small airway epithelium (SAE) and alveolar areas using computer-assisted Image-Pro Plus 7.0 software. IPF and LAM tissue was also immunostained for myofibroblast marker α-smooth muscle actin (α-SMA) and growth factor transforming growth factor beta1 (TGF-ß1). Compared to HC, ACE2, TMPRSS2 and Furin expression were significantly upregulated in the SAE of IPF (p < 0.01) and LAM (p < 0.001) patients, and in the alveolar areas of IPF (p < 0.001) and LAM (p < 0.01). There was a significant positive correlation between smoking history and ACE2 expression in the IPF cohort for SAE (r = 0.812, p < 0.05) and alveolar areas (r = 0.941, p < 0.01). This, to our knowledge, is the first study to compare ACE2, TMPRSS2, and Furin expression in patients with IPF and LAM compared to HC. Descriptive images show that α-SMA and TGF-ß1 increase in the IPF and LAM tissue. Our data suggests that patients with ILDs are at a higher risk of developing severe COVID-19 infection and post-COVID-19 interstitial pulmonary fibrosis. Growth factors secreted by the myofibroblasts, and surrounding tissue could further affect COVID-19 adhesion proteins/cofactors and post-COVID-19 interstitial pulmonary fibrosis. Smoking seems to be the major driving factor in patients with IPF.

Transcripts associated with chronic lung allograft dysfunction in transbronchial biopsies of lung transplants.

Transplanted lungs suffer worse outcomes than other organ transplants with many developing chronic lung allograft dysfunction (CLAD), diagnosed by physiologic changes. Histology of transbronchial biopsies (TBB) yields little insight, and the molecular basis of CLAD is not defined. We hypothesized that gene expression in TBBs would reveal the nature of CLAD and distinguish CLAD from changes due simply to time posttransplant. Whole-genome mRNA profiling was performed with microarrays in 498 prospectively collected TBBs from the INTERLUNG study, 90 diagnosed as CLAD. Time was associated with increased expression of inflammation genes, for example, CD1E and immunoglobulins. After correcting for time, CLAD manifested not as inflammation but as parenchymal response-to-wounding, with increased expression of genes such as HIF1A, SERPINE2, and IGF1 that are increased in many injury and disease states and cancers, associated with development, angiogenesis, and epithelial response-to-wounding in pathway analysis. Fibrillar collagen genes were increased in CLAD, indicating matrix changes, and normal transcripts were decreased-dedifferentiation. Gene-based classifiers predicted CLAD with AUC 0.70 (no time-correction) and 0.87 (time-corrected). CLAD related gene sets and classifiers were strongly prognostic for graft failure and correlated with CLAD stage. Thus, in TBBs, molecular changes indicate that CLAD primarily reflects severe parenchymal injury-induced changes and dedifferentiation.

Abnormal one-year post-lung transplant spirometry is a significant predictor of increased mortality and chronic lung allograft dysfunction.

BACKGROUND: The prognostic value of evaluating spirometry at a fixed time point using standardized population reference has not previously been evaluated. Our aim was to assess the association between spirometric phenotype at 12 months (Spiro12M), survival and incidence of chronic lung allograft dysfunction (CLAD) in bilateral lung transplant recipients. METHODS: We conducted a retrospective cohort study of bilateral lung transplant recipients transplanted between January 2003 and September 2012. We defined Spiro12M as the mean of the 2 prebronchodilator FEV1 measurements 12-month post-transplant. Normal spirometry was defined as FEV1/FVC ≥0.7 and FEV1≥80% and FVC≥80% predicted population-based values for that recipient. Abnormal spirometry was defined as failure to attain normal function by 12-months. We used a Cox regression model to assess the association between Spiro12M, survival, and CLAD. We used logistic regression to assess potential pretransplant donor and recipient factors associated with abnormal Spiro12M RESULTS: One hundred and eleven (51%) lung transplant recipients normalized their Spiro12M. Normal Spiro12M was associated improved survival (hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.41-0.88], p = 0.009. Each 10% decrement in FEV1 increased the risk of death in a stepwise fashion. Additionally, CLAD was reduced in those with normal Spiro12M (HR:0.65, 95%CI:0.46-0.92, p = 0.016). Donor smoking history (OR:2.93, 95% CI:1.21-7.09; p = 0.018) and mechanical ventilation time in hours (OR:1.03, 95% CI:1.004-1.05; p = 0.02) were identified as independent predictors of abnormal Spiro12M. CONCLUSIONS: Abnormal Spiro12M is associated with increased mortality and the development of CLAD. The effect is dose dependent with increased dysfunction corresponding to increased risk. This assessment of phenotype at 12-months can easily be incorporated into standard of care.

Physical activity decline is disproportionate to decline in pulmonary physiology in IPF.

BACKGROUND AND OBJECTIVE: Patients with idiopathic pulmonary fibrosis (IPF) have reduced levels of daily physical activity (DPA); however, little is known about how DPA changes as disease progresses. We aimed to (i) describe change in DPA over 12 months, (ii) analyse its association with conventional markers of disease severity and quality of life and (iii) assess DPA as a prognostic tool. METHODS: A total of 54 patients with IPF had DPA monitored at baseline and at 6 and 12 months with a SenseWear armband for 7 consecutive days. Participants completed the Hospital Anxiety and Depression scale, St George's Respiratory Questionnaire and Leicester Cough Questionnaire at each time point and provided clinical data including forced vital capacity (FVC), diffusion capacity of carbon monoxide and 6-min walk distance (6MWD). RESULTS: Baseline and 12-month daily step count (DSC) were 3887 (395) and 3326 (419), respectively. A significant reduction in DSC (mean = 645 [260], p = 0.02) and total energy expenditure (mean = 486 kJ [188], p = 0.01) was demonstrated at 12 months. The decline in DSC over 12 months was proportionally larger than decline in lung function. Annual change in DPA had weak to moderate correlation with annual change in FVC % predicted and 6MWD (range r = 0.34-0.45). Change in physical activity was not associated with long-term survival. CONCLUSION: In IPF, decline in DPA over 12 months is significant and disproportionate to decline in pulmonary physiology and may be a useful tool for assessment of disease progression.

Molecular phenotyping of rejection-related changes in mucosal biopsies from lung transplants.

Diagnosing lung transplant rejection currently depends on histologic assessment of transbronchial biopsies (TBB) with limited reproducibility and considerable risk of complications. Mucosal biopsies are safer but not histologically interpretable. Microarray-based diagnostic systems for TBBs and other transplants suggest such systems could assess mucosal biopsies as well. We studied 243 mucosal biopsies from the third bronchial bifurcation (3BMBs) collected from seven centers and classified them using unsupervised machine learning algorithms. Using the expression of a set of rejection-associated transcripts annotated in kidneys and validated in hearts and lung transplant TBBs, the algorithms identified and scored major rejection and injury-related phenotypes in 3BMBs without need for labeled training data. No rejection or injury, rejection, late inflammation, and recent injury phenotypes were thus scored in new 3BMBs. The rejection phenotype correlated with IFNG-inducible transcripts, the hallmarks of rejection. Progressive atrophy-related changes reflected by the late inflammation phenotype in 3BMBs suggest widespread time-dependent airway deterioration, which was especially pronounced after two years posttransplant. Thus molecular assessment of 3BMBs can detect rejection in a previously unusable biopsy format with potential utility in patients with severe lung dysfunction where TBB is not possible and provide unique insights into airway deterioration. ClinicalTrials.gov NCT02812290.

The complex existence of γδ T cells following transplantation: the good, the bad and the simply confusing.

Gamma delta (γδ) T cells are a highly heterogeneous population of lymphocytes that exhibit innate and adaptive immune properties. Despite comprising the majority of residing lymphocytes in many organs, the role of γδ T cells in transplantation outcomes is under-researched. γδ T cells can recognise a diverse array of ligands and exert disparate effector functions. As such, they may potentially contribute to both allograft acceptance and rejection, as well as impacting on infection and post-transplant malignancy. Here, we review the current literature on the role and function of γδ T cells following solid organ and hematopoietic stem cell transplantation.

Molecular assessment of rejection and injury in lung transplant biopsies.

BACKGROUND: Improved understanding of lung transplant disease states is essential because failure rates are high, often due to chronic lung allograft dysfunction. However, histologic assessment of lung transplant transbronchial biopsies (TBBs) is difficult and often uninterpretable even with 10 pieces. METHODS: We prospectively studied whether microarray assessment of single TBB pieces could identify disease states and reduce the amount of tissue required for diagnosis. By following strategies successful for heart transplants, we used expression of rejection-associated transcripts (annotated in kidney transplant biopsies) in unsupervised machine learning to identify disease states. RESULTS: All 242 single-piece TBBs produced reliable transcript measurements. Paired TBB pieces available from 12 patients showed significant similarity but also showed some sampling variance. Alveolar content, as estimated by surfactant transcript expression, was a source of sampling variance. To offset sampling variation, for analysis, we selected 152 single-piece TBBs with high surfactant transcripts. Unsupervised archetypal analysis identified 4 idealized phenotypes (archetypes) and scored biopsies for their similarity to each: normal; T-cell‒mediated rejection (TCMR; T-cell transcripts); antibody-mediated rejection (ABMR)-like (endothelial transcripts); and injury (macrophage transcripts). Molecular TCMR correlated with histologic TCMR. The relationship of molecular scores to histologic ABMR could not be assessed because of the paucity of ABMR in this population. CONCLUSIONS: Molecular assessment of single-piece TBBs can be used to classify lung transplant biopsies and correlated with rejection histology. Two or 3 pieces for each TBB will probably be needed to offset sampling variance.

Casein Kinase 1δ/ε Inhibitor, PF670462 Attenuates the Fibrogenic Effects of Transforming Growth Factor-ß in Pulmonary Fibrosis.

Transforming growth factor-beta (TGF-ß) is a major mediator of fibrotic diseases, including idiopathic pulmonary fibrosis (IPF). However, therapeutic global inhibition of TGF-ß is limited by unwanted immunosuppression and mitral valve defects. We performed an extensive literature search to uncover a little-known connection between TGF-ß signaling and casein kinase (CK) activity. We have examined the abundance of CK1 delta and epsilon (CK1δ/ε) in lung tissue from IPF patients and non-diseased controls, and investigated whether inhibition of CK1δ/ε with PF670462 inhibits pulmonary fibrosis. CK1δ/ε levels in lung tissue from IPF patients and non-diseased controls were assessed by immunohistochemistry. Anti-fibrotic effects of the CK1δ/ε inhibitor PF670462 were assessed in pre-clinical models, including acute and chronic bleomycin mouse models and in vitro experiments on spheroids made from primary human lung fibroblast cells from IPF and control donors, and human A549 alveolar-like adenocarcinoma-derived epithelial cells. Increased expression of CK1δ and ε in IPF lungs compared to non-diseased controls was accompanied by increased levels of the product, phospho-period 2. In vitro, PF670462 prevented TGF-ß-induced epithelial-mesenchymal transition. The stiffness of IPF-derived spheroids was reduced by PF670462 and TGF-ß-induced fibrogenic gene expression was inhibited. The CK1δ/ε inhibitor PF670462 administered systemically or locally by inhalation prevented both acute and chronic bleomycin-induced pulmonary fibrosis in mice. PF670462 administered in a 'therapeutic' regimen (day 7 onward) prevented bleomycin-induced lung collagen accumulation. Elevated expression and activity of CK1 δ and ε in IPF and anti-fibrogenic effects of the dual CK1δ/ε inhibitor, PF670462, support CK1δ/ε as novel therapeutic targets for IPF.

Cyclophosphamide for connective tissue disease-associated interstitial lung disease.

BACKGROUND: Approximately one-third of individuals with interstitial lung disease (ILD) have associated connective tissue disease (CTD). The connective tissue disorders most commonly associated with ILD include scleroderma/systemic sclerosis (SSc), rheumatoid arthritis, polymyositis/dermatomyositis, and Sjögren's syndrome. Although many people with CTD-ILD do not develop progressive lung disease, a significant proportion do progress, leading to reduced physical function, decreased quality of life, and death. ILD is now the major cause of death amongst individuals with systemic sclerosis.Cyclophosphamide is a highly potent immunosuppressant that has demonstrated efficacy in inducing and maintaining remission in autoimmune and inflammatory illnesses. However this comes with potential toxicities, including nausea, haemorrhagic cystitis, bladder cancer, bone marrow suppression, increased risk of opportunistic infections, and haematological and solid organ malignancies.Decision-making in the treatment of individuals with CTD-ILD is difficult; the clinician needs to identify those who will develop progressive disease, and to weigh up the balance between a high level of need for therapy in a severely unwell patient population against the potential for adverse effects from highly toxic therapy, for which only relatively limited data on efficacy can be found. Similarly, it is not clear whether histological subtype, disease duration, or disease extent can be used to predict treatment responsiveness. OBJECTIVES: To assess the efficacy and adverse effects of cyclophosphamide in the treatment of individuals with CTD-ILD. SEARCH METHODS: We performed searches on CENTRAL, MEDLINE, Embase, CINAHL, and Web of Science up to May 2017. We handsearched review articles, clinical trial registries, and reference lists of retrieved articles. SELECTION CRITERIA: We included randomised controlled parallel-group trials that compared cyclophosphamide in any form, used individually or concomitantly with other immunomodulating therapies, versus non-cyclophosphamide-containing therapies for at least six months, with follow-up of at least 12 months from the start of treatment. DATA COLLECTION AND ANALYSIS: We imported studies identified by the search into a reference manager database. We retrieved the full-text versions of relevant studies, and two review authors independently extracted data. Primary outcomes were change in lung function (change in forced vital capacity (FVC) % predicted and diffusing capacity of the lung for carbon monoxide (DLCO) % predicted), adverse events, and health-related quality of life measures. Secondary outcomes included all-cause mortality, dyspnoea, cough, and functional exercise testing. When appropriate, we performed meta-analyses and subgroup analyses by severity of lung function, connective tissue disease diagnosis, and radiological pattern of fibrosis. We assessed the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach and created 'Summary of findings' tables. MAIN RESULTS: We included in the analysis four trials with 495 participants (most with systemic sclerosis). We formed two separate comparisons: cyclophosphamide versus placebo (two trials, 195 participants) and cyclophosphamide versus mycophenolate (two trials, 300 participants). We found evidence to be of low quality, as dropout rates were high in the intervention groups, and as we noted a wide confidence interval around the effect with small differences, which affected the precision of results.The data demonstrates significant improvement in lung function with cyclophosphamide compared with placebo (post-treatment FVC % mean difference (MD) 2.83, 95% confidence interval (CI) 0.80 to 4.87; P = 0.006) but no significant difference in post-treatment DLCO (% MD -1.68, 95% CI -4.37 to 1.02; P = 0.22; two trials, 182 participants).Risk of adverse effects was increased in the cyclophosphamide treatment groups compared with the placebo groups, in particular, haematuria, leukopenia, and nausea, leading to a higher rate of withdrawal from cyclophosphamide treatment. The data demonstrates statistically significant improvement in one-measure of quality of life in one trial favouring cyclophosphamide over placebo and clinically and statistically significant improvement in breathlessness in one trial favouring cyclophosphamide compared with placebo, with no significant impact on mortality.Trialists reported no significant impact on lung function when cyclophosphamide was used compared with mycophenolate at 12 months (FVC % MD -0.82, 95% CI -3.95 to 2.31; P = 0.61; two trials, 149 participants; DLCO % MD -1.41, 95% CI -10.40 to 7.58; P = 0.76; two trials, 149 participants).Risk of side effects was increased with cyclophosphamide versus mycophenolate, in particular, leukopenia and thrombocytopenia.The data demonstrates no significant impact on health-related quality of life, all-cause mortality, dyspnoea, or cough severity in the cyclophosphamide group compared with the mycophenolate group. No trials reported outcomes associated with functional exercise tests.We performed subgroup analysis to determine whether severity of lung function, connective tissue disease diagnosis, or radiological pattern had any impact on outcomes. One trial reported that cyclophosphamide protected against decreased FVC in individuals with worse fibrosis scores, and also showed that cyclophosphamide may be more effective in those with worse lung function. No association could be made between connective tissue disease diagnosis and outcomes. AUTHORS' CONCLUSIONS: This review, which is based on studies of varying methodological quality, demonstrates that overall, in this population, small benefit may be derived from the use of cyclophosphamide in terms of mean difference in % FVC when compared with placebo, but not of the difference in % DLCO, or when compared with mycophenolate. Modest clinical improvement in dyspnoea may be noted with the use of cyclophosphamide. Clinical practice guidelines should advise clinicians to consider individual patient characteristics and to expect only modest benefit at best in preserving FVC. Clinicians should carefully monitor for adverse effects during treatment and in the years thereafter.Further studies are required to examine the use of cyclophosphamide; they should be adequately powered to compare outcomes within different subgroups, specifically, stratified for extent of pulmonary infiltrates on high-resolution computed tomography (HRCT) and skin involvement in SSc. Studies on other forms of connective tissue disease are needed. Researchers may consider comparing cyclophosphamide (a potent immunosuppressant) versus antifibrotic agents, or comparing both versus placebo, in particular, for those with evidence of rapidly progressive fibrotic disease, who may benefit the most.

Continued Successful Evolution of Extended Criteria Donor Lungs for Transplantation.

BACKGROUND: In an era of increasing ex vivo lung perfusion (EVLP) use, it remains important to describe what outcomes can be achieved without EVLP, by taking an aggressive approach to donor use to maximize lung transplantation. METHODS: Data for all lung transplant donor referrals to the Alfred Hospital in Melbourne, Australia were collected for 2012 to 2013. Donor variables were analyzed and calculated into a previously validated lung donor score. Lung transplant recipient outcome data included the following: primary graft dysfunction; duration of mechanical ventilation; need for cardiopulmonary bypass extracorporeal membrane oxygenation; intensive care and hospital length of stay; 30-day, 1-year, and 3- to 4-year survival rates; rates of acute rejection and chronic lung allograft dysfunction; and peak and 12-month lung function (forced expiratory volume in 1 second). RESULTS: Of the 318 lung donor offers, 129 resulted in successful lung transplantation, with an overall donor use rate of 41%. There was no correlation between donor score and any of the recipient outcomes, and excellent short-term and longer-term survival was achieved. CONCLUSIONS: Future studies examining lung transplantation outcomes with EVLP must consider the excellent results that can be achieved by using marginal lungs and conventional donor management. It is important to consider that adopting a strategy of perioperative lung donor evaluation and intervention allows use of what are considered marginal lungs to achieve promising results.

Refractory Pulmonary Edema Caused by Late Pulmonary Vein Thrombosis After Lung Transplantation: A Rare Adverse Event.

After lung transplantation, pulmonary vein thrombosis is a rare, potentially life-threatening adverse event arising at the pulmonary venous anastomosis that typically occurs early and presents as graft failure and hemodynamic compromise with an associated mortality of up to 40%. The incidence, presentation, outcomes, and treatment of late pulmonary vein thrombosis remain poorly defined. Management options include anticoagulant agents for asymptomatic clots, and thrombolytic agents or surgical thrombectomy for hemodynamically significant clots. We present a rare case highlighting a delayed presentation of pulmonary vein thrombosis occurring longer than 2 weeks after lung transplantation and manifesting clinically as graft failure secondary to refractory pulmonary edema. The patient was treated successfully with surgical thrombectomy and remains well. We recommend a high index of suspicion of pulmonary vein thrombosis when graft failure after lung transplantation occurs and is not responsive to conventional therapy, and consideration of investigation with transesophageal echocardiography or computed tomography with venous phase contrast in such patients even more than 2 weeks after lung transplantation.

The Presence of HLA-E-Restricted, CMV-Specific CD8+ T Cells in the Blood of Lung Transplant Recipients Correlates with Chronic Allograft Rejection.

The human cytomegalovirus (CMV) immune evasion protein, UL40, shares an identical peptide sequence with that found in the leader sequence of many human leukocyte antigen (HLA)-C alleles and when complexed with HLA-E, can modulate NK cell functions via interactions with the CD94-NKG2 receptors. However the UL40-derived sequence can also be immunogenic, eliciting robust CD8+ T cell responses. In the setting of solid organ transplantation these T cells may not only be involved in antiviral immunity but also can potentially contribute to allograft rejection when the UL40 epitope is also present in allograft-encoded HLA. Here we assessed 15 bilateral lung transplant recipients for the presence of HLA-E-restricted UL40 specific T cells by tetramer staining of peripheral blood mononuclear cells (PBMC). UL40-specific T cells were observed in 7 patients post-transplant however the magnitude of the response varied significantly between patients. Moreover, unlike healthy CMV seropositive individuals, longitudinal analyses revealed that proportions of such T cells fluctuated markedly. Nine patients experienced low-grade acute cellular rejection, of which 6 also demonstrated UL40-specific T cells. Furthermore, the presence of UL40-specific CD8+ T cells in the blood was significantly associated with allograft dysfunction, which manifested as Bronchiolitis Obliterans Syndrome (BOS). Therefore, this study suggests that minor histocompatibility antigens presented by HLA-E can represent an additional risk factor following lung transplantation.

Clinical outcomes of lung transplant recipients with telomerase mutations.

BACKGROUND: Successful lung transplantation for patients with pulmonary fibrosis from telomerase mutations may be limited by systemic complications of telomerase dysfunction, including myelosuppression, cirrhosis, and malignancy. We describe clinical outcomes in 14 lung transplant recipients with telomerase mutations. METHODS: Subjects underwent lung transplantation between February 2005 and April 2014 at 5 transplant centers. Data were abstracted from medical records, focusing on outcomes reflecting post-transplant treatment effects likely to be complicated by telomerase mutations. RESULTS: The median age of subjects was 60.5 years (interquartile range = 52.0-62.0), 64.3% were male, and the mean post-transplant observation time was 3.2 years (SD ± 2.9). A mutation in telomerase reverse transcriptase was present in 11 subjects, a telomerase RNA component mutation was present in 2 subjects, and an uncharacterized mutation was present in 1 subject. After lung transplantation, 10 subjects were leukopenic and 5 did not tolerate lymphocyte anti-proliferative agents. Six subjects developed recurrent lower respiratory tract infections, 7 developed acute cellular rejection (A1), and 4 developed chronic lung allograft dysfunction. Eight subjects developed at least 1 episode of acute renal failure and 10 developed chronic renal insufficiency. In addition, 3 subjects developed cancer. No subjects had cirrhosis. At data censorship, 13 subjects were alive. CONCLUSIONS: The clinical course for lung transplant recipients with telomerase mutations is complicated by renal disease, leukopenia with intolerance of lymphocyte anti-proliferative agents, and recurrent lower respiratory tract infections. In contrast, cirrhosis was absent, acute cellular rejection was mild, and development of chronic lung allograft dysfunction was comparable to other lung transplant recipients. Although it poses challenges, lung transplantation may be feasible for patients with pulmonary fibrosis from telomerase mutations.

Bronchoscopic procedures and lung biopsies in pediatric lung transplant recipients.

Bronchoscopy remains a pivotal diagnostic and therapeutic intervention in pediatric patients undergoing lung transplantation (LTx). Whether performed as part of a surveillance protocol or if clinically indicated, fibre-optic bronchoscopy allows direct visualization of the transplanted allograft, and in particular, an assessment of the patency of the bronchial anastomosis (or tracheal anastomosis following heart-lung transplantation). Additionally, bronchoscopy facilitates differentiation of infective processes from rejection episodes through collection and subsequent assessment of bronchoalveolar lavage (BAL) and transbronchial biopsy (TBBx) samples. Indeed, the diagnostic criteria for the grading of acute cellular rejection is dependent upon the histopathological assessment of biopsy samples collected at the time of bronchoscopy. Typically, performed in an out-patient setting, bronchoscopy is generally a safe procedure, although complications related to hemorrhage and pneumothorax are occasionally seen. Airway complications, including stenosis, malacia, and dehiscence are diagnosed at bronchoscopy, and subsequent management including balloon dilatation, laser therapy and stent insertion can also be performed bronchoscopically. Finally, bronchoscopy has been and continues to be an important research tool allowing a better understanding of the immuno-biology of the lung allograft through the collection and analysis of collected BAL and TBBx samples. Whilst new investigational tools continue to evolve, the simple visualization and collection of samples within the lung allograft by bronchoscopy remains the gold standard in the evaluation of the lung allograft. This review describes the use and experience of bronchoscopy following lung transplantation in the pediatric setting.

Long-term successful outcomes from kidney transplantation after lung and heart-lung transplantation.

BACKGROUND: Renal dysfunction is common after lung and heart-lung transplantation (Tx), and it limits the recipient's survival and quality of life. This study analyzed the outcomes of simultaneous and late kidney Tx following lung and heart-lung Tx. METHODS: From a single-center retrospective chart review of 1031 lung and heart-lung Tx recipients, we identified 13 simultaneous or late kidney Tx cases in 12 patients. RESULTS: Three patients underwent simultaneous deceased donor lung and kidney Tx. Eight patients underwent lung and heart-lung Tx, followed by nine living donor kidney Tx (including one ABO-incompatible Tx). One additional patient underwent a late deceased donor kidney Tx following heart-lung Tx. The median time from lung and heart-lung Tx to later kidney Tx was 127 (interquartile range [IQR], 23 to 263) months. Three patients died, 1 of sepsis, 1 of multiple organ failure, and 1 of transplant coronary disease. At a median follow-up of 33 (IQR, 10 to 51) months, 9 patients are alive and well. Eight patients required dialysis before kidney Tx for a median time of 14 months (IQR, 5 to 49). Kidney graft loss occurred in 1 patient at 51 months. After kidney Tx, dialysis was necessary in association with acute allograft dysfunction in 2 patients. No acute kidney rejection has been detected in any patient. Treatable acute lung rejection was seen in 1 patient. Well-preserved pulmonary function was noted in recipients of late kidney Tx. CONCLUSIONS: Simultaneous kidney Tx and late deceased donor kidney Tx have challenges in the setting of lung Tx. By contrast, late living related kidney Tx after lung Tx is associated with excellent long-term survival and acceptable kidney and lung allograft function.

Managing central venous obstruction in cystic fibrosis recipients--lung transplant considerations.

BACKGROUND: The superior vena cava (SVC) syndrome in cystic fibrosis (CF) patients is rare, but presents unique challenges in the peri-transplant period. We reviewed our experience of SVC syndrome in CF recipients undergoing lung transplantation. METHODS: This is a retrospective case series from a single center chart-review. SVC obstruction is defined by clinically significant stenosis or obstruction of the SVC as detected by contrast studies. RESULTS: We identified SVC obstruction in seven post-transplant cases and one pre-transplant case. All eight patients had previous or current history of indwelling central venous catheters. Three recipients experienced operative complications. Five of the seven recipients suffered at least one episode of post-operative SVC obstruction or bleeding despite prophylactic anticoagulation. At a median follow-up of 29 months, six of the seven patients transplanted are well. CONCLUSIONS: Strategies are available to minimize the risks of intra/peri-operative acute life-threatening SVC obstruction in CF patients.