Iron controls the development of airway hyperreactivity by regulating ILC2 metabolism and effector function.

Group 2 innate lymphoid cells (ILC2s) rapidly induce a type 2 inflammation in the lungs in response to allergens. Here, we focused on the role of iron, a critical nutritional trace element, on ILC2 function and asthma pathogenesis. We found that transferrin receptor 1 (TfR1) is rapidly up-regulated and functional during ILC2 activation in the lungs, and blocking transferrin uptake reduces ILC2 expansion and activation. Iron deprivation reprogrammed ILC2 metabolism, inducing a HIF-1α-driven up-regulation of glycolysis and inhibition of oxidative mitochondrial activity. Consequently, we observed that in vivo iron chelation or induction of hypoferremia reduced the development of airway hyperreactivity in experimental models of ILC2-driven allergic asthma. Human circulating ILC2s rapidly induced TfR1 during activation, whereas inhibition of iron uptake or iron deprivation reduced effector functions. Last, we found a negative relationship between circulating ILC2 TfR1 expression and airway function in cohorts of patients with asthma. Collectively, our studies define cellular iron as a critical regulator of ILC2 function.

Blocking CD226 regulates type 2 innate lymphoid cell effector function and alleviates airway hyperreactivity.

BACKGROUND: Type 2 innate lymphoid cells (ILC2s) play a pivotal role in type 2 asthma. CD226 is a costimulatory molecule involved in various inflammatory diseases. OBJECTIVE: We aimed to investigate CD226 expression and function within human and mouse ILC2s, and to assess the impact of targeting CD226 on ILC2-mediated airway hyperreactivity (AHR). METHODS: We administered IL-33 intranasally to wild-type mice, followed by treatment with anti-CD226 antibody or isotype control. Pulmonary ILC2s were sorted for ex vivo analyses through RNA sequencing and flow cytometry. Next, we evaluated the effects of CD226 on AHR and lung inflammation in wild-type and Rag2-/- mice. Additionally, we compared peripheral ILC2s from healthy donors and asthmatic patients to ascertain the role of CD226 in human ILC2s. RESULTS: Our findings demonstrated an inducible expression of CD226 in activated ILC2s, enhancing their cytokine secretion and effector functions. Mechanistically, CD226 alters intracellular metabolism and enhances PI3K/AKT and MAPK signal pathways. Blocking CD226 ameliorates ILC2-dependent AHR in IL-33 and Alternaria alternata-induced models. Interestingly, CD226 is expressed and inducible in human ILC2s, and its blocking reduces cytokine production. Finally, we showed that peripheral ILC2s in asthmatic patients exhibited elevated CD226 expression compared to healthy controls. CONCLUSION: Our findings underscore the potential of CD226 as a novel therapeutic target in ILC2s, presenting a promising avenue for ameliorating AHR and allergic asthma.

Effect of bronchial thermoplasty on static and dynamic lung compliance and resistance in patients with severe persistent asthma.

RATIONALE: Bronchial thermoplasty (BT) reduces severity and frequency of bronchoconstriction and symptoms in severe, persistent asthmatics although it is usually not associated with change in spirometric variables. Other than spirometry. there are almost no data on changes in lung mechanics following BT. OBJECTIVE: To assess lung static and dynamic lung compliance (Cst,L and Cdyn,L, respectively) and static and dynamic lung resistance (Rst,L and Rdyn,L, respectively) before and after BT in severe asthmatics using the esophageal balloon technique. METHODS: Rdyn,L and Cdyn,L were measured at respiratory frequencies up to 145 breaths/min, using the esophageal balloon technique in 7 patients immediately before and 12-50 weeks after completing a series of 3 BT sessions. RESULTS: All patients experienced improved symptoms within a few weeks following completion of BT. Pre-BT, all patients exhibited frequency dependency of lung compliance, with mean Cdyn,L decreasing to 63% of Cst,L at maximum respiratory rates. Post-BT, Cst,L did not change significantly from pre-thermoplasty values, while Cdyn,L diminished to 62%% of Cst,L. In 4 of 7 patients, post-BT values of Cdyn,L were consistently higher than pre-BT over the range of respiratory rates. RL in 4 of 7 patients during quiet breathing and at higher respiratory frequencies decreased following BT. CONCLUSIONS: Patients with severe persistent asthma exhibit increased resting lung resistance and frequency dependence of compliance, the magnitudes of which are ameliorated in some patients following bronchial thermoplasty and associated with variable change in frequency dependence of lung resistance. These findings are related to asthma severity and may be related to the heterogeneous and variable nature of airway smooth muscle modeling and its response to BT.

Safety and effectiveness of bronchial thermoplasty after 10 years in patients with persistent asthma (BT10+): a follow-up of three randomised controlled trials.

BACKGROUND: Bronchial thermoplasty is an endoscopic treatment for uncontrolled asthma. Previous randomised clinical trials have shown that bronchial thermoplasty reduces severe exacerbations in people with asthma. However, the long-term efficacy and safety of bronchial thermoplasty beyond 5 years is unknown. The BT10+ study aimed to investigate the efficacy and safety of bronchial thermoplasty after 10 or more years of follow-up. METHODS: BT10+ was an international, multicentre, follow-up study of participants who were previously enrolled in the AIR, RISA, and AIR2 trials and who had 10 or more years of follow-up since bronchial thermoplasty treatment. Data on patient demographics, quality of life, lung function, CT scans (AIR2 participants only), severe exacerbations, and health-care use during the previous year were collected at the BT10+ 10-year outcomes study visit. The primary effectiveness endpoint was durability of the thermoplasty treatment effect, determined by comparing the proportion of participants who had severe exacerbations during the first and fifth years after bronchial thermoplasty treatment with the proportion of participants who had severe exacerbations during the 12-month period before the BT10+ visit. The primary safety endpoint was the absence of clinically significant post-treatment respiratory image changes after bronchial thermoplasty, defined as bronchiectasis or bronchial stenosis as confirmed by pulmonary volumetric high-resolution CT scan at the BT10+ visit (AIR2 participants only). All analyses were done on an intention-to-treat basis. The trial is registered with ClinicalTrials.gov, NCT03243292. The last patient was enrolled on Dec 11, 2018. The last patient completed follow-up on Jan 10, 2019. FINDINGS: The BT10+ study enrolled 192 (45%) of the 429 participants who were enrolled in the AIR, RISA, and AIR2 trials. The BT10+ participants comprised 136 who received bronchial thermoplasty (52% of the 260 participants who received bronchial thermoplasty in the original trials), and 56 sham or control participants (33% of 169 from the original trials). 18 (32%) sham or control participants received bronchial thermoplasty after the previous trials concluded. The participants included in BT10+ were followed for 10·8-15·6 years (median 12·1 years) post-treatment. Baseline characteristics were similar between participants enrolled in BT10+ and those not enrolled. Participants treated with bronchial thermoplasty had similar proportions of severe exacerbations at the BT10+ visit (34 [25%] of 136 participants) compared with 1 year (33 [24%] of 135 participants; difference 0·6%, 95% CI -9·7 to 10·8) and 5 years (28 [22%] of 130 participants; difference 3·5%, -6·7% to 13·6) after treatment. Quality of life measurements and spirometry were similar between year 1, year 5, and the BT10+ visit. At the BT10+ study visit, pulmonary high-resolution CT scans from AIR2 participants treated with bronchial thermoplasty showed that 13 (13%) of 97 participants had bronchiectasis. When compared with baseline high-resolution CT scans, six (7%) of 89 participants treated with bronchial thermoplasty who did not have bronchiectasis at baseline had developed bronchiectasis after treatment (5 classified as mild, 1 classified as moderate). Participants treated with bronchial thermoplasty after the original study and participants in the sham or control group also had reductions in severe exacerbations at the BT10+ visit compared with baseline. INTERPRETATION: Our findings suggest that efficacy of bronchial thermoplasty is sustained for 10 years or more, with an acceptable safety profile. Therefore, bronchial thermoplasty is a long-acting therapeutic option for patients with asthma that remains uncontrolled despite optimised medical treatment. FUNDING: Boston Scientific.

Lack of association of Aspergillus colonization with the development of bronchiolitis obliterans syndrome in lung transplant recipients: An international cohort study.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is a major limitation in the long-term survival of lung transplant recipients (LTRs). However, the risk factors in the development of BOS remain undetermined. We conducted an international cohort study of LTRs to assess whether Aspergillus colonization with large or small conidia is a risk factor for the development of BOS. METHODS: Consecutive LTRs from January 2005 to December 2008 were evaluated. Rates of BOS and associated risk factors were recorded at 4 years. International Society of Heart and Lung Transplantation criteria were used to define fungal and other infections. A Cox proportional-hazards-model was constructed to assess the association between Aspergillus colonization and the development of BOS controlling for confounders. RESULTS: A total of 747 LTRs were included. The cumulative incidence of BOS at 4 years after transplant was 33% (250 of 747). Additionally, 22% of LTRs experienced Aspergillus colonization after transplantation. Aspergillus colonization with either large (hazard ratio [HR] = 0.6, 95% confidence interval [CI] = 0.3-1.2, p = 0.12) or small conidia (HR = 0.9, 95% CI = 0.6-1.4, p = 0.74) was not associated with the development of BOS. Factors associated with increased risk of development of BOS were the male gender (HR = 1.4, 95% CI = 1.1-1.8, p = 0.02) and episodes of acute rejection (1-2 episodes, HR = 1.5, 95% CI = 1.1-2.1, p = 0.014; 3-4 episodes, HR = 1.6, 95% CI = 1.0-2.6, p = 0.036; >4 episodes, HR = 2.2, 95% CI = 1.1-4.3, p = 0.02), whereas tacrolimus use was associated with reduced risk of BOS (HR = 0.6, 95% CI = 0.5-0.9, p = 0.007). CONCLUSIONS: We conclude from this large multicenter cohort of lung transplant patients, that Aspergillus colonization with large or small conidia did not show an association with the development of BOS.

Comparison of Skin Cancer Incidence in Caucasian and Non-Caucasian Liver Vs. Lung Transplant Recipients: A Tale of Two Regimens.

BACKGROUND: Organ transplantation is a significant risk factor for the development of skin cancer. The impact of skin type, immunosuppressive regimens, and photosensitizing agents requires further study. OBJECTIVE: The objective of this study was to compare skin cancer development between Caucasian and non-Caucasian transplant recipients at the University of Southern California. METHODS: We performed a retrospective chart review of lung and liver transplantations to determine the incidence of post-transplant skin cancer. Participants included patients who underwent lung or liver transplantation between 2005 and 2013 at our institution. Patients included in the study were limited to those who survived through the study observation period. RESULTS: We analyzed 475 patients who underwent transplantation, including 370 liver transplant recipients and 105 lung transplant recipients. Among these, 46.3% identified as Caucasian, while 53.7% were non-Caucasian. Over a mean follow-up of 7.9 years, 11.8% of Caucasian patients developed at least one skin cancer, compared with 2.7% of non-Caucasians (p < 0.001). However, irrespective of race, skin cancer development was significantly greater in lung compared with liver transplant recipients (20.0% vs. 3.2%, p < 0.001). The standard immunosuppressive and prophylactic regimens were mycophenolate mofetil and tacrolimus based for both transplants. Mycophenolate mofetil was maintained throughout the course in lung transplant patients, whereas this agent was reduced and terminated when possible in liver transplant recipients. In addition, during the years examined, voriconazole, a known photosensitizing agent, was used in lung transplant recipients to prevent aspergillosis. CONCLUSIONS: Fair skin type increases post-transplant skin cancer development, irrespective of the immunosuppressive regimen. A higher risk of skin cancer is associated with different regimens; in particular photosensitizing agents may increase risk in transplant recipients.

Clinical risk factors for invasive aspergillosis in lung transplant recipients: Results of an international cohort study.

BACKGROUND: Invasive aspergillosis (IA) is a frequent complication in lung transplant recipients (LTRs). Clinical risk factors for IA have not been fully characterized, especially in the era of extensive anti-fungal prophylaxis. The primary objective of this study was to evaluate the clinical risk factors associated with IA in LTRs. The secondary objective was to assess the mortality in LTRs who had at least 1 episode of IA compared with LTRs who never had experienced IA. METHODS: We conducted an international, multicenter, retrospective cohort study of 900 consecutive adults who received lung transplants between 2005 and 2008 with 4years of follow-up. Risk factors associated with IA were identified using univariate and multiple regression Cox proportional hazards models. RESULTS: Anti-fungal prophylaxis was administered to 61.7% (555 of 900) of patients, and 79 patients developed 115 episodes of IA. The rate to development of the first episode was 29.6 per 1,000 person-years. Aspergillus fumigatus was the most common species isolated (63% [72 of 115 episodes]). Through multivariate analysis, significant risk factors identified for IA development were single lung transplant (hazard ratio, 1.84; 95% confidence interval, 1.09-3.10; p = 0.02,) and colonization with Aspergillus at 1 year post-transplantation (hazard ratio, 2.11; 95% confidence interval, 1.28-3.49; p = 0.003,). Cystic fibrosis, pre-transplant colonization with Aspergillus spp, and use of anti-fungal prophylaxis were not significantly associated with the development of IA. Time-dependent analysis showed IA was associated with higher mortality rates. CONCLUSION: Incidence of IA remains high in LTRs. Single-lung transplant and airway colonization with Aspergillus spp. within 1 year post-transplant were significantly associated with IA.

Further Studies of Unsuspected Emphysema in Nonsmoking Patients With Asthma With Persistent Expiratory Airflow Obstruction.

BACKGROUND: Previously, we and other investigators have described reversible loss of lung elastic recoil in patients with acute and persistent, moderate-to-severe, chronic, treated asthma who never smoked, and its adverse effect on maximal expiratory airflow. In four consecutive autopsies, we reported the pathophysiologic mechanism(s) has been unsuspected mild, diffuse, middle and upper lobe centrilobular emphysema. METHODS: We performed prospective studies (5 to 22 years) in 25 patients (12 female) with chronic asthma, age 55 ± 15 years, who never smoked, with persistent moderate-to-severe expiratory obstruction. Studies included measuring blood eosinophils, IgE, total exhaled nitric oxide (NO), central airway NO flux, peripheral airway/alveolar NO concentration, impulse oscillometry, heliox curves, lung elastic recoil, and high-resolution thin-section (1 mm) lung CT imaging at full inspiration with voxel quantification. RESULTS: In 25 patients with stable asthma with varying type 2 phenotype, after 270 µg of aerosolized albuterol sulfate had been administered with a metered dose inhaler with space chamber, FVC was 3.1 ± 1.0 L (83% ± 13% predicted) (mean ± SD), FEV1 was 1.8 ± 0.6 L (59% ± 11%), the FEV1/FVC ratio was 59% ± 10%, and the ratio of single-breath diffusing capacity of the lung for carbon monoxide to alveolar volume was 4.8 ± 1.1 mL/min/mm Hg/L (120% ± 26%). All 25 patients with asthma had loss of static lung elastic recoil pressure, which contributed equally to decreased intrinsic airway conductance in limiting expiratory airflow. Lung CT scanning detected none or mild emphysema. In all four autopsied asthmatic lungs previously reported and one unreported explanted lung, microscopy revealed unsuspected mild, diffuse centrilobular emphysema in the upper and middle lung fields, and asthma-related remodeling in airways. In eight cases, during asthma remission, there were increases in measured static lung elastic recoil pressure-calculated intrinsic airway conductance, and measured maximal expiratory airflow at effort-independent lung volumes. CONCLUSIONS: As documented now in five cases, unsuspected microscopic mild centrilobular emphysema is the sentinel cause of loss of lung elastic recoil. This contributes significantly to expiratory airflow obstruction in never-smoking patients with asthma, with normal diffusing capacity and near-normal lung CT scan results. TRIAL REGISTRY: Protocol No. 20070934 and Study No. 1090472, Western Institutional Review Board, Olympia, WA; ClinicalTrials.gov; No. NCT00576069; URL: www.clinicaltrials.gov.

Lack of autophagy induces steroid-resistant airway inflammation.

BACKGROUND: Neutrophilic corticosteroid-resistant asthma accounts for a significant proportion of asthma; however, little is known about the mechanisms that underlie the pathogenesis of the disease. OBJECTIVE: We sought to address the role of autophagy in lung inflammation and the pathogenesis of corticosteroid-resistant neutrophilic asthma. METHODS: We developed CD11c-specific autophagy-related gene 5 (Atg5)(-/-) mice and used several murine models to investigate the role of autophagy in asthmatic patients. RESULTS: For the first time, we found that deletion of the Atg5 gene specifically in CD11c(+) cells, which leads to impairment of the autophagy pathway, causes unprovoked spontaneous airway hyperreactivity and severe neutrophilic lung inflammation in mice. We found that severe lung inflammation impairs the autophagy pathway, particularly in pulmonary CD11c(+) cells in wild-type mice. We further found that adoptive transfer of Atg5(-/-), but not wild-type, bone marrow-derived dendritic cells augments lung inflammation with increased IL-17A levels in the lungs. Our data indicate that neutrophilic asthma in Atg5(-/-) mice is glucocorticoid resistant and IL-17A dependent. CONCLUSION: Our results suggest that lack of autophagy in pulmonary CD11c(+) cells induces neutrophilic airway inflammation and hyperreactivity.

Bronchial thermoplasty: Long-term safety and effectiveness in patients with severe persistent asthma.

BACKGROUND: Bronchial thermoplasty (BT) has previously been shown to improve asthma control out to 2 years in patients with severe persistent asthma. OBJECTIVE: We sought to assess the effectiveness and safety of BT in asthmatic patients 5 years after therapy. METHODS: BT-treated subjects from the Asthma Intervention Research 2 trial (ClinicalTrials.govNCT01350414) were evaluated annually for 5 years to assess the long-term safety of BT and the durability of its treatment effect. Outcomes assessed after BT included severe exacerbations, adverse events, health care use, spirometric data, and high-resolution computed tomographic scans. RESULTS: One hundred sixty-two (85.3%) of 190 BT-treated subjects from the Asthma Intervention Research 2 trial completed 5 years of follow-up. The proportion of subjects experiencing severe exacerbations and emergency department (ED) visits and the rates of events in each of years 1 to 5 remained low and were less than those observed in the 12 months before BT treatment (average 5-year reduction in proportions: 44% for exacerbations and 78% for ED visits). Respiratory adverse events and respiratory-related hospitalizations remained unchanged in years 2 through 5 compared with the first year after BT. Prebronchodilator FEV1 values remained stable between years 1 and 5 after BT, despite a 18% reduction in average daily inhaled corticosteroid dose. High-resolution computed tomographic scans from baseline to 5 years after BT showed no structural abnormalities that could be attributed to BT. CONCLUSIONS: These data demonstrate the 5-year durability of the benefits of BT with regard to both asthma control (based on maintained reduction in severe exacerbations and ED visits for respiratory symptoms) and safety. BT has become an important addition to our treatment armamentarium and should be considered for patients with severe persistent asthma who remain symptomatic despite taking inhaled corticosteroids and long-acting ß2-agonists.

Near fatal asthma: clinical and airway biopsy characteristics.

Background. Inflammation and remodeling are integral parts of asthma pathophysiology. We sought to describe the clinical and pathologic features of near fatal asthma exacerbation (NFE). Methods. Bronchial biopsies were collected prospectively from NFE I subjects. Another NFE II group and a moderate severity exacerbation control group (ME II) were retrospectively identified-no biopsies obtained. Results. All NFE II (n = 9) subjects exhibited remodeling and significant inflammation (eosinophilic, neutrophilic). NFE II group (n = 37) had a significant history of prior intubation and inhaled corticosteroids usage compared to ME II group (n = 41). They also exhibited leukocytosis, eosinophilia, and longer hospitalization days. Conclusions. Remodeling, eosinophilic, and neutrophilic inflammation were observed in NFE. NFE is associated with prior intubation and inhaled corticosteroids usage.

Outcomes after lung transplantation and practices of lung transplant programs in the United States regarding hepatitis C seropositive recipients.

BACKGROUND: The estimated prevalence of hepatitis C virus (HCV) infection among lung transplant (LT) recipients is 1.9%. Many thoracic transplant programs are reluctant to transplant HCV-seropositive patients due to concerns of hepatic dysfunction caused by immunosuppression. The aims of this study are to survey current practices of US LT programs regarding HCV-seropositive patients and using the Organ Procurement and Transplantation Network/United Network for Organ Sharing database and to assess the clinical outcomes of HCV-positive compared with HCV-negative LT recipients. METHODS: A survey of US transplant centers that have performed more than 100 LTs was conducted. In addition, 170 HCV-seropositive and 9259 HCV-seronegative recipients who received HCV-seronegative donor organs between January 1, 2000, to December 31, 2007, were identified from the Organ Procurement and Transplantation Network/United Network for Organ Sharing database. Outcome variables including patient survival were compared between the two groups. RESULTS: A total of 64.4% centers responded to the survey. Ten of 29 (34.5%) programs would not consider HCV-seropositive patients for LT. Among the 19 programs that will consider HCV-seropositive patients, only five centers would transplant actively viremic patients. Overall patient survival rates of HCV-seropositive patients were similar to HCV-seronegative patients (84.7% at 1 year, 63.9% at 3 years, 49.4% at 5 years for HCV-seropositive group vs. 82.0% at 1 year, 65.0% at 3 years, 51.4% at 5 years for HCV-seronegative group, P=0.712). Relative risk of recipients for death remained statistically insignificant after adjusting for recipient age, donor age, obesity, sensitization, serum creatinine, and medical condition at time of transplant (relative risk [RR]=1.07 [0.84-1.38], P=0.581). CONCLUSIONS: Since 2000, patient survival rates of HCV-positive patients are identical to those who are HCV-negative. However, most of these HCV-seropositive patients were probably nonviremic.

Pericardial constriction after lung transplantation.

Pericardial constriction is extremely rare after lung transplantation. We present a case and review the potential contributing factors for pericardial constriction after lung transplantation. Treatment for this condition, irrespective of the cause, remains pericardiectomy.

Effectiveness and safety of bronchial thermoplasty in the treatment of severe asthma: a multicenter, randomized, double-blind, sham-controlled clinical trial.

RATIONALE: Bronchial thermoplasty (BT) is a bronchoscopic procedure in which controlled thermal energy is applied to the airway wall to decrease smooth muscle. OBJECTIVES: To evaluate the effectiveness and safety of BT versus a sham procedure in subjects with severe asthma who remain symptomatic despite treatment with high-dose inhaled corticosteroids and long-acting beta(2)-agonists. METHODS: A total of 288 adult subjects (Intent-to-Treat [ITT]) randomized to BT or sham control underwent three bronchoscopy procedures. Primary outcome was the difference in Asthma Quality of Life Questionnaire (AQLQ) scores from baseline to average of 6, 9, and 12 months (integrated AQLQ). Adverse events and health care use were collected to assess safety. Statistical design and analysis of the primary endpoint was Bayesian. Target posterior probability of superiority (PPS) of BT over sham was 95%, except for the primary endpoint (96.4%). MEASUREMENTS AND MAIN RESULTS: The improvement from baseline in the integrated AQLQ score was superior in the BT group compared with sham (BT, 1.35 +/- 1.10; sham, 1.16 +/- 1.23 [PPS, 96.0% ITT and 97.9% per protocol]). Seventy-nine percent of BT and 64% of sham subjects achieved changes in AQLQ of 0.5 or greater (PPS, 99.6%). Six percent more BT subjects were hospitalized in the treatment period (up to 6 wk after BT). In the posttreatment period (6-52 wk after BT), the BT group experienced fewer severe exacerbations, emergency department (ED) visits, and days missed from work/school compared with the sham group (PPS, 95.5, 99.9, and 99.3%, respectively). CONCLUSIONS: BT in subjects with severe asthma improves asthma-specific quality of life with a reduction in severe exacerbations and healthcare use in the posttreatment period. Clinical trial registered with www.clinialtrials.gov (NCT00231114).

Long-term pulmonary function after living-donor lobar lung transplantation in adults.

BACKGROUND: Living-donor lobar lung transplantation was developed as an alternative to cadaveric transplantation. However, whether two pulmonary lobes provide comparable intermediate and long-term pulmonary function to full-sized bilateral cadaveric grafts in adults is unknown. METHODS: An analysis of the pulmonary functions of 59 bilateral lobar and 43 bilateral cadaveric adult lung transplant recipients who survived more than 3 months after transplantation was performed. RESULTS: Mean follow-up was 3.8 +/- 2.8 years. In lobar recipients, mean percent predicted forced vital capacity and forced expiratory volume in 1 second improved between 1 and 6 months after transplantation (42.5% +/- 13.4% and 46.9% +/- 14.0% at 1 month versus 63.6% +/- 14.1% and 64.5% +/- 13.7% at 6 months; p < 0.001 and <0.001, respectively). In cadaveric recipients, mean percent predicted forced vital capacity improved after transplantation (54.3% +/- 14.5% at 1 month versus 74.2% +/- 21.3% at 12 months; p < 0.01). As compared with the cadaveric group, mean percent predicted forced vital capacity and forced expiratory volume in 1 second were lower 1 and 3 months after transplantation in the lobar recipients (p = 0.001 at both times); however, by 6 months after transplantation, these values were comparable and remained so throughout the follow-up period. In a subset of lobar and cadaveric recipients, maximal exercise, heart rate, peak oxygen consumption, anaerobic oxygen consumption threshold, and ability to maintain oxygen saturation were also comparable. CONCLUSIONS: In those adult recipients surviving more than 3 months after transplantation, lobar lung transplantation provides comparable intermediate and long-term pulmonary function and exercise capacity to bilateral cadaveric lung transplantation.

A decade of living lobar lung transplantation: perioperative complications after 253 donor lobectomies.

Living lobar lung transplantation places two donors at risk for each recipient. We examined the perioperative outcomes associated with the 253 donor lobectomies performed at our institution during our first decade of living lobar lung transplantation. There have been no perioperative or long-term deaths. 80.2% of donors (n = 203) had no perioperative complications, while fifty (19.8%) had one or more complication. The incidence of intraoperative complications was 3.6%. Complications requiring reoperation occurred in 3.2% of donors. 15.0% of donors had other perioperative complications; the most serious were two donors who developed pulmonary artery thrombosis, while the most common was the need for an additional thoracostomy tube or a thoracostomy tube for >/=14 d for persistent air leaks and/or drainage. Right-sided donors were more likely to have a perioperative complication than left-sided donors (odd ratio 2.02, p = 0.04), probably secondary to right lower and middle lobe anatomy. This experience has shown donor lobectomy to be associated with a relatively low morbidity and no mortality, and is important if this procedure is to be considered an option at more pulmonary transplant centers, given continued organ shortages and differences in philosophical and ethical acceptance of live

A decade of living lobar lung transplantation: recipient outcomes.

OBJECTIVE: Living lobar lung transplantation was developed as a procedure for patients considered too ill to await cadaveric transplantation. METHODS: One hundred twenty-eight living lobar lung transplantations were performed in 123 patients between 1993 and 2003. Eighty-four patients were adults (age, 27 +/- 7.7 years), and 39 were pediatric patients (age, 13.9 +/- 2.9 years). RESULTS: The primary indication for transplantation was cystic fibrosis (84%). At the time of transplantation, 67.5% of patients were hospitalized, and 17.9% were intubated. One-, 3-, and 5-year actuarial survival among living lobar recipients was 70%, 54%, and 45%, respectively. There was no difference in actuarial survival between adult and pediatric living lobar recipients (P =.65). There were 63 deaths among living lobar recipients, with infection being the predominant cause (53.4%), followed by obliterative bronchiolitis (12.7%) and primary graft dysfunction (7.9%). The overall incidence of acute rejection was 0.8 episodes per patient. Seventy-eight percent of rejection episodes were unilateral. Age, sex, indication, donor relationship, preoperative hospitalization status, use of preoperative steroids, and HLA-A, HLA-B, and HLA-DR typing did not influence survival. However, patients on ventilators preoperatively had significantly worse outcomes (odds ratio, 3.06, P =.03; Kaplan-Meier P =.002), and those undergoing retransplantation had an increased risk of death (odds ratio, 2.50). CONCLUSION: These results support the continued use of living lobar lung transplantation in patients deemed unable to await a cadaveric transplantation. We consider patients undergoing retransplantations and intubated patients to be at significantly high risk because of the poor outcomes in these populations.

Regulation of activin A expression in mast cells and asthma: its effect on the proliferation of human airway smooth muscle cells.

Activin A, a homodimeric protein (betaAbetaA) and a member of the TGF-beta superfamily, is involved in the inflammatory repair process. Using cDNA microarray analysis, we discovered strong induction of the activin betaA gene in human mast cells (MC) on stimulation with PMA and calcium ionophore (A23187). Activin betaA mRNA was also highly induced in primary cultured murine bone marrow MC (BMMC) after stimulation by IgE receptor cross-linking. Secretion of activin A was evident in human mast cell-1 line cells 3 h after stimulation and progressively increased over time. Activin A was present in the cytoplasm of activated but not unstimulated murine bone marrow MC as demonstrated by immunofluorescence studies, suggesting that secretion of activin A by MC was due to de novo synthesis rather than secretion of preformed protein. Activin A also colocalized with human lung MC from patients with asthma by double-immunofluorescence staining. Furthermore, secretion of activin A was significantly increased in the airway of wild-type mice after OVA sensitization followed by intranasal challenge. Secretion of activin A, however, was greatly reduced in MC-deficient WBB6F(1)-W/W(v) mice as compared with wild-type mice, indicating that MC are an important contributor of activin A in the airways of a murine asthma model. Additionally, activin A promoted the proliferation of human airway smooth muscle cells. Taken together, these data suggest that MC-derived activin A may play an important role in the process of airway remodeling by promoting the proliferation of airway smooth muscle.