Peter Jaksch

Inducible NOS Inhibition Reverses Tobacco-Smoke-Induced Emphysema and Pulmonary Hypertension in Mice

Chronic obstructive pulmonary disease (COPD) is one of the most common causes of death worldwide. We report in an emphysema model of mice chronically exposed to tobacco smoke that pulmonary vascular dysfunction, vascular remodeling, and pulmonary hypertension (PH) precede development of alveolar destruction. We provide evidence for a causative role of inducible nitric oxide synthase (iNOS) and peroxynitrite in this context. Mice lacking iNOS were protected against emphysema and PH. Treatment of wild-type mice with the iNOS inhibitor N(6)-(1-iminoethyl)-L-lysine (L-NIL) prevented structural and functional alterations of both the lung vasculature and alveoli and also reversed established disease. In chimeric mice lacking iNOS in bone marrow (BM)-derived cells, PH was dependent on iNOS from BM-derived cells, whereas emphysema development was dependent on iNOS from non-BM-derived cells. Similar regulatory and structural alterations as seen in mouse lungs were found in lung tissue from humans with end-stage COPD.

Primary Lung Transplantation After Bridge With Extracorporeal Membrane Oxygenation: A Plea for a Shift in Our Paradigms for Indications

Background. The introduction of the lung allocation score has brought lung transplantation (LTX) of patients on extracorporeal membrane oxygenation (ECMO) bridge into the focus of interest. We reviewed our institutional experience with ECMO as a bridge to LTX. Methods. Between 1998 and 2011, 38 patients (median age 30.1 years, range 13–66 years) underwent ECMO support with intention to bridge to primary LTX. The underlying diagnosis was cystic fibrosis (n=17), pulmonary hypertension (n=4), idiopathic pulmonary fibrosis (n=9), adult respiratory distress syndrome (n=4), hemosiderosis (n=1), bronchiolitis obliterans (n=1), sarcoidosis (n=1), and bronchiectasis (n=1). The type of extracorporeal bridge was venovenous (n=18), venoarterial (n=15), interventional lung assist (n=1), or a stepwise combination of them (n=4). The median bridging time was 5.5 days (range 1–63) days. The type of transplantation was double LTX (n=7), size-reduced double LTX (n=8), lobar LTX (n=16), split LTX (n=2), and lobar LTX after ex vivo lung perfusion (n=1). Results. Four patients died before transplantation. Thirty-four patients underwent LTX, of them eight patients died in the hospital after a median stay of 24.5 days (range 1–180 days). Twenty-six patients left the hospital and returned to normal life (median hospital stay=47.5 days; range 21–90 days). The 1-, 3-, and 5-year survival for all transplanted patients was 60%, 60%, and 48%, respectively. The 1-, 3-, and 5-year survival conditional on 3-month survival for patients bridged with ECMO to LTX (78%, 78%, and 63%) was not worse than for other LTX patients within the same period of time (90%, 80%, and 72%, respectively, P=0.09, 0.505, and 0.344). Conclusion. Transplantation of patients bridged on ECMO to LTX is feasible and results in acceptable outcome.

Guidelines on the use of extracorporeal photopheresis

After the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T‐cell lymphoma was published in 1983 with its subsequent recognition by the FDA for its refractory forms, the technology has shown significant promise in the treatment of other severe and refractory conditions in a multi‐disciplinary setting. Among the major studied conditions are graft versus host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection and inflammatory bowel disease.

Extracorporeal photopheresis: Past, present, and future

Extracorporeal photopheresis (ECP) is a leukapheresis-based therapy that uses 8-methoxypsoralen and ultraviolet A irradiation. Used alone or in combination with biological agents, ECP is an established and effective therapy for advanced cutaneous T-cell lymphoma. ECP has also shown promising efficacy in a number of other severe and difficult-to-treat conditions, including systemic sclerosis, graft-versus-host disease, prevention and treatment of rejection in solid organ transplantation, and Crohn disease. Furthermore, the use of ECP in some of these conditions may allow a significant reduction in the use of systemic steroids and other immunosuppressants, reducing long-term morbidity and mortality. The accumulated experience shows ECP to be well tolerated, with no clinically significant side effects. Progress is also being made in the search for understanding of the mechanisms of action of ECP, which will ultimately facilitate improvements in the use of this therapy.

A Th17- and Th2-skewed Cytokine Profile in Cystic Fibrosis Lungs Represents a Potential Risk Factor for Pseudomonas aeruginosa Infection

RATIONALE Cystic fibrosis (CF) is characterized by progressive pulmonary inflammation that is infection-triggered. Pseudomonas aeruginosa represents a risk factor for deterioration of lung function and reduced life expectancy. OBJECTIVES To assess T-cell cytokine/chemokine production in clinically stable children with CF and evaluate the association between T-cell subtypes and susceptibility for infection with P. aeruginosa. METHODS T-cell cytokine/chemokine profiles were measured in bronchoalveolar lavage fluid (BALF) from children with CF (n = 57; 6.1 ± 5.9 yr) and non-CF control subjects (n = 18; 5.9 ± 4.3 yr). Memory responses to Aspergillus fumigatus and P. aeruginosa were monitored. High-resolution computed tomography-based Helbich score was assessed. In a prospective observational trial the association between BALF cytokine/chemokine profiles and subsequent infection with P. aeruginosa was studied. MEASUREMENTS AND MAIN RESULTS Th1- (INF-γ), Th2- (IL-5, IL-13), Th17- (IL-17A), and Th17-related cytokines (IL-1β, IL-6) were significantly up-regulated in airways of patients with CF. IL-17A, IL-13, and IL-5 were significantly higher in BALF of symptomatic as compared with clinically asymptomatic patients with CF. IL-17A and IL-5 correlated with the percentage of neutrophils in BALF (r = 0.41, P < 0.05 and r = 0.46, P < 0.05, respectively). Th17- (IL-17A, IL-6, IL-1β, IL-8) and Th2-associated cytokines and chemokines (IL-5, IL-13, TARC/CCL17), but not IFN-γ levels, significantly correlated with high-resolution computed tomography changes (Helbich score; P < 0.05). P. aeruginosa- and A. fumigatus-specific T cells from patients with CF displayed significantly higher IL-5 and IL-17A mRNA expression. IL-17A and TARC/CCL17 were significantly augmented in patients that developed P. aeruginosa infection within 24 months. CONCLUSIONS We propose a role for Th17 and Th2 T cells in chronic inflammation in lungs of patients with CF. High concentrations of these cytokines/chemokines in CF airways precede infection with P. aeruginosa.

Emergence of Multiple Cytomegalovirus Strains in Blood and Lung of Lung Transplant Recipients

Background. Cytomegalovirus (CMV) is a major pathogen in lung transplant recipients (LTRs). The emergence of different CMV strains in lung and blood after transplantation has not yet been analyzed. Methods. In total, 75 serum and 91 broncheoalveolar lavage (BAL) samples obtained from 25 LTRs in the follow-up after transplantation were tested for the presence of different CMV strains. The gB, gN, and gO genes of the CMV isolates were analyzed by subtype-specific PCR, restriction fragment length polymorphism (RFLP), sequencing, and phylogenetic analysis. Results. Mixed CMV-strain populations were detected after cessation of antiviral prophylaxis in up to 80% and 90% of the patients’ BAL and serum, respectively, and this was independent of the CMV serostatus of donor and recipient. In five patients, the same single CMV strain was consistently detectable over at least 1 year in lung and blood, although in two of these cases donor and recipient had both been CMV-seropositive. Most CMV strains were distributed in the lung and blood compartment. Symptomatic CMV infection within the first year after transplantation was observed only in patients with mixed CMV-strain populations (P<0.05). Conclusion. Most LTRs harbor more than one CMV strain in their lung and blood compartment after cessation of prophylaxis, but the CMV strain distribution within and between the compartments varies between individuals and is not associated with the donor/recipient serostatus. The data further show that compartmentalization of CMV strains in lung versus blood seems to be a rare event and that the presence of mixed CMV-strain infections within the first year after transplantation may be disadvantageous for LTRs.

Relationship between Cytomegalovirus DNA Load in Epithelial Lining Fluid and Plasma of Lung Transplant Recipients and Analysis of Coinfection with Epstein-Barr Virus and Human Herpesvirus 6 in the Lung Compartment

ABSTRACT Cytomegalovirus (CMV) is a significant cause of morbidity and mortality in lung transplant recipients (LTRs). The aim of the present study was to elucidate the relationship between the CMV DNA load in the lung compartment and that in plasma. For CMV load determination, the level of CMV DNA in plasma and bronchoalveolar lavage (BAL) samples was measured in a total of 97 paired BAL and plasma samples obtained from 25 LTRs. The original virus concentration in the epithelial lining fluid (ELF) was calculated from the BAL samples by correcting for dilution using the urea dilution method. In addition, the load of Epstein-Barr virus (EBV) and that of human herpesvirus 6 (HHV-6) DNA also were determined in BAL samples, recalculated for their concentrations in the ELF, and compared with the CMV DNA load. CMV DNA was found more frequently and at significantly higher levels in the lung compartment than in plasma (P < 0.001, Wilcoxon test), and the CMV load in the ELF was associated with symptomatic CMV disease. EBV and HHV-6 were detected in 43.6% and 21.7% of the ELF samples, respectively. A statistically significant association was found between the CMV and EBV DNA loads in the ELF (P < 0.001; Spearmans rho = 0.651). Thus, in LTRs, determination of the CMV DNA load in the lung compartment may be advantageous compared to monitoring only viremia. The significant relationship between EBV and CMV DNA loads in the ELF of LTRs and its clinical impact require further investigation.

A prospective interventional study on the use of extracorporeal photopheresis in patients with bronchiolitis obliterans syndrome after lung transplantation

BACKGROUND The aim of this prospective study was to evaluate the efficacy and safety of extracorporeal photopheresis (ECP) in patients with bronchiolitis obliterans syndrome (BOS) after lung transplantation and to identify factors predicting treatment response. METHODS The study was performed at a single center and consisted of a cohort of 1,012 lung transplant recipients (November 1989-June 2010). A total of 194 patients developed BOS after a mean of 1,293 ± 1,008 days (range, 99-4,949 days) and received established treatment, and 51 patients received additional ECP. RESULTS Thirty-one (61%) of the ECP-treated patients responded to the therapy and showed sustained stabilization (forced expiratory volume in 1 second range, -5% to 5% vs baseline at start of ECP) of lung function over 6 months. Responders to ECP showed significantly greater survival and less need for retransplantation (p = 0.001) than non-responders. Factors associated with an inferior treatment response were cystic fibrosis as underlying lung disease and a longer time between transplantation and development of BOS. No side effects were observed after ECP. Compared with BOS patients not treated with ECP, the ECP responders showed an improved graft survival (p = 0.05). CONCLUSIONS These results confirm and suggest that early use of ECP could be an effective adjunct treatment for patients who develop BOS after lung transplantation.

Pulmonary Retransplantation: Is it Worth the Effort? A Long-term Analysis of 46 Cases

BACKGROUND Pulmonary retransplantation remains the only therapeutic option in some cases of severe primary graft dysfunction (PGD), advanced bronchiolitis obliterans syndrome (BOS), and in some cases of severe airway problems (AWP), mainly cicatriceal stenosis. However, its value has been questioned due to the overall scarcity of donor organs and reports indicating unsatisfactory outcome. We analyzed our institutional experience with pulmonary retransplantation to evaluate its value for different indications. METHODS We retrospectively analyzed all 46 patients undergoing pulmonary retransplantation from the 567 consecutive primary lung or heart-lung transplantations performed in our department from August 1995 to August 2006. We stratified patients according to indication for retransplantation and analyzed the outcome. RESULTS Forty-six patients (mean age 41 +/- 16 years, 18 men and 28 women) underwent pulmonary retransplantation (14 bilateral lung transplantations, 32 single-lung transplantations) for primary graft dysfunction (n = 23), bronchiolitis obliterans syndrome (n = 19) and airway problems (n = 4). Mean time to retransplantation was 26 +/- 27 days in the PGD group, 1,069 +/- 757 days in the BOS group and 220 +/- 321 days in the AWP group. Thirty-day, 1-year and 5-year survival rates after retransplantation were 52.2%, 34.8% and 29.0% in the PGD group and 89.2%, 72.5% and 61.3% in the BOS group, respectively. All 4 patients in the AWP group are presently alive (BOS vs PGD: p = 0.02; BOS vs AWP: p = 0.27; PGD vs AWP: p = 0.06). CONCLUSIONS Pulmonary retransplantation for bronchiolitis obliterans offers long-term survival rates in the range of primary lung transplantation for selected patients. Long-term survival rates for retransplantation due to PGD are significantly lower, warranting restrictive use in this setting. In our experience with a limited number of patients, retransplantation for airway problems has shown excellent results. Pulmonary retransplantation for chronic problems is a plausible approach, provided that patients are carefully selected. Retransplantation for PGD should be avoided.

Cytomegalovirus Prevention in High-risk Lung Transplant Recipients: Comparison of 3- vs 12-Month Valganciclovir Therapy

BACKGROUND Cytomegalovirus (CMV) infections are common after lung transplantation (LuTx) and have an influence on acute rejection rates and chronic organ dysfunction. The objective of this study was to determine the incidence of CMV infections by comparing a prolonged valganciclovir prophylaxis with a standard regimen in high-risk LuTx recipients. METHODS A retrospective, single-center study was performed comparing two different CMV prophylactic regimens in high-risk LuTx recipients (D(+)/R(-)). The study population received either 3 months (Group A, 15 patients) or 12 months (Group B, 17 patients) of oral valganciclovir 900 mg/day in combination with CMV hyperimmune globulin in four doses (Days 1, 7, 14 and 21 post-transplant). RESULTS CMV viremia was noted in 11 of 15 patients in Group A (75%) and 5 of 17 in Group B (33%) (p < 0.05) at 6 months after valganciclovir cessation. The incidence of symptomatic CMV disease/syndrome was 6 of 15 (44%) in Group A and 2 of 17 in Group B (13%) (p < 0.05). Histologically proven acute rejection episodes of ISHLT Grade > or =A2 were found in 4 patients in Group A and in 1 patient in Group B within the first year (p = 0.14). CONCLUSIONS A 12-month CMV prophylaxis with oral valganciclovir is effective in significantly reducing CMV viremia and CMV disease/syndrome in high-risk lung transplant recipients. In addition, a reduction in acute and recurrent rejection episodes was observed, possibly due to less CMV viremia and subsequent immunomodulatory effects.