Christer Kjellström

Bronchiolitis obliterans syndrome in lung transplant recipients is associated with increased neutrophil activity and decreased antioxidant status in the lung

Long-term survival of lung transplant recipients is limited by the advent of obliterative bronchiolitis and irreversible airways obstruction, e.g. bronchiolitis obliterans syndrome (BOS). This study investigated whether inflammatory cells and their activation markers were increased in bronchoalveolar lavage (BAL) and transbronchial biopsies (TBB) from patients with BOS. Levels of antioxidants in BAL fluid were also assessed. BAL fluid and TBB from six single-lung, two bilateral-lung, and five heart-lung transplanted patients with diagnosis of BOS were compared with 13 transplant recipients without BOS. BAL fluid levels of myeloperoxidase (MPO), eosinophil cationic protein (ECP) and interleukin (IL)-8 were used as markers for the activation and attraction of neutrophils and eosinophils, respectively. Immunohistochemical staining of TBB with monoclonal antibodies to MPO and ECP (EG2) was performed. Significantly increased BAL percentages of neutrophils and levels of MPO were found in patients with BOS. The findings correlated well with the degree of monoclonal staining for MPO in TBB. BAL levels of ECP and IL-8 were significantly increased in BOS patients. BAL concentrations of the water-soluble antioxidants ascorbate, urate and glutathione were generally lower in BOS patients. The results indicate that neutrophil infiltration and activation, as well as oxidative stress, may play a role in the development and/or progression of bronchiolitis obliterans syndrome. Markers for neutrophil activation could have a potential role in monitoring disease activity in patients with this syndrome.

Persistent high BAL fluid granulocyte activation marker levels as early indicators of bronchiolitis obliterans after lung transplant

The major cause of mortality in the long-term in lung transplant recipients is chronic rejection. This is a fibroproliferative process in the small airways leading to obliterative bronchiolitis and progressive loss of lung function, both constituting the clinical entity bronchiolitis obliterans syndrome (BOS). Granulocyte activation has been implicated as one factor behind BOS. Granulocyte markers in bronchoalveolar lavage (BAL) fluid were prospectively and longitudinally studied in order to identify possible association with BOS. BAL fluid from 266 bronchoscopy procedures performed in twelve single lung, eight bilateral lung and five heart/lung transplant recipients were analysed. The majority (19 of 25) were studied for a period of 2 yrs after surgery. Myeloperoxidase (MPO), eosinophil cationic protein (ECP) and interleukin-8 (IL-8) levels were used as indirect markers of activation and attraction of granulocytes. Five patients developed BOS. Ninety-eight episodes of acute rejection, nine of bacterial infection, 19 of cytomegalovirus pneumonitis, nine of Pneumocystis carinii infection, two of aspergillus infection and two of respiratory syncytial virus infection were diagnosed. BOS patients had significantly higher mean levels of MPO, ECP and IL-8 compared to patients without BOS, irrespective of acute rejection status. Over time, the five patients with BOS had significantly elevated BAL fluid levels of MPO and ECP as well as neutrophil percentages, and in four patients this increase preceded the clinical diagnosis of BOS by several months. Elevated bronchoalveolar lavage fluid neutrophil percentage as well as levels of the granulocyte activation markers myeloperoxidase and eosinophil cationic protein appear to be early signs of development of BOS in lung transplant recipients.

Compromised antioxidant status and persistent oxidative stress in lung transplant recipients.

Oxidative stress may be a key feature, and hence important determinant, of tissue injury and allograft rejection in lung transplant recipients. To investigate this, we determined the antioxidant status (urate, ascorbate, thiols and alpha-tocopherol) and lipid peroxidation status (malondialdehyde) in bronchoalveolar lavage (BAL) fluid and blood serum of 19 consecutive lung transplant recipients 2 weeks and 1, 2, 3, 6, and 12 months post-surgery. BAL fluid and blood samples from 23 control subjects and blood from 8 patients two days before transplantation were obtained for comparison. Before surgery, the antioxidant status of patients was poor as serum ascorbate and total thiol concentrations were significantly (p < 0.05) lower than control subjects. Two weeks post-surgery, ascorbate and total thiol concentrations were still low and urate concentrations had fallen compared to control subjects (p < 0.01). At this time, BAL fluid urate concentration was higher (p < 0.01), ascorbate concentration was lower (p < 0.01) and reduced glutathione concentrations were similar to control subjects. MDA, a product of lipid peroxidation, was higher (p < 0.01) in both BAL fluid and serum obtained from transplant patients compared to control subjects. During the first 12 months post-surgery, little improvement in antioxidant status or extent of lipid peroxidation was seen in transplant recipients. Regression analysis indicated no difference in serum or BAL fluid antioxidant status in patients with acute rejection compared to those without. In conclusion, lung transplant recipients have a compromised antioxidant status before surgery and it remains poor for at least the first year following the operation. In addition, these patients have elevated MDA concentrations in both their lung lining fluid and blood over most of this time. Oxidative stress is not, however, a sufficiently sensitive endpoint to predict tissue rejection in this group.

Inflammatory cells and activation markers in BAL during acute rejection and infection in lung transplant recipients: a prospective, longitudinal study

Acute rejection of the transplanted lung is a clinical problem, since it decreases graft survival and predisposes the patient to chronic rejection and obliterative bronchiolitis (OB). In an earlier study, we had indications that eosinophil cationic protein (ECP) from activated eosinophils and hyaluronan (HYA) from fibroblasts were associated with acute pulmonary rejection. This prospective longitudinal study was designed to investigate whether molecules from activated inflammatory cells in bronchoalveolar lavage (BAL) fluid could serve as clinically useful diagnostic markers for acute rejection. BAL fluid from 138 bronchoscopies performed in 10 single lung, four bilateral lung and five heart-lung transplant recipients were analysed. Nine patients were studied for a period of more than 1 yr (mean 13.4 months) after surgery. Differential cell counts were made from the BAL fluid. ECP, myeloperoxidase (MPO), HYA and interleukin-8 (IL-8) were used as indirect markers for activation and attraction of eosinophils, neutrophils and fibroblasts, respectively. Fifty four episodes of acute rejection were diagnosed. Two patients developed OB. Nine episodes of bacterial infection, 13 episodes of cytomegalovirus (CMV) pneumonitis, three of Pneumocystis carinii infection and one of respiratory syncytial virus (RSV) infection were diagnosed. The mean levels of ECP, MPO, HYA and IL-8 were all higher during rejection episodes, but differences were not statistically significant compared to no rejection, when the confounding factors of time, concomitant infection, and repeated measures in the same individual had been accounted for. We could not confirm that measurements of eosinophil cationic protein, myeloperoxidase, hyaluronan and interleukin-8 in bronchoalveolar lavage fluid can be used as diagnostic markers for acute rejection in the postoperative follow-up of lung transplant recipients.

Plasmapheresis as a rescue therapy to resolve cardiac rejection with vasculitis and severe heart failure. A report of five cases

The predominant causes of late graft loss and death after cardiac transplantation are graft rejection and infection. The histopathological classification of acute rejection is based on cellular phenomena such as lymphocytic infiltration and myocyte damage. The adverse prognostic importance of vascular or humoral rejection has been reported, but there is no well-documented treatment available. In our experience, comprising 151 orthotopic transplants, five patients presented with graft rejection characterized by a lymphocytic vasculitis that did not respond to conventional therapy. Because of a deteriorating condition, in spite of vigorous antirejection treatment that included inotropic drugs and circulatory support, plasmapheresis was tried as a last, desperate means to stop the process from developing further. The clinical symptoms rapidly subsided in all five patients after the first couple of plasma exchanges. All of the patients are alive and well after 2–3.5 years of follow-up. Although the mechanism of action is unclear, plasmapheresis was beneficial in these critically ill patients.

Tricuspid valve insufficiency as a complication of endomyocardial biopsy

The purpose of this study was to investigate the occurrence of major tricuspid insufficiency caused by endomyocardial biopsy in heart transplant recipients. Endomyocardial biopsy was used for the detection of rejection and Doppler echocardiography was performed at regular intervals. Six of 96 heart transplant patients (6.3%) had sudden appearance of large tricuspid regurgitation, all of which were directly related to a preceding biopsy. Chordal tissue was identified histologically in biopsy samples of all six patients. All patients developed symptoms of right ventricular failure which was confirmed by right heart catheterization. Three patients subsequently underwent valvuloplasty for ruptured chordae tendineae of either of the three leaflets. Two of these three patients were free from symptoms during follow-up, but the third patient developed moderate tricuspid regurgitation and clinical symptoms. It is concluded that endomyocardial biopsy, although it is the most useful tool for detection of rejection, should be used with caution with regard to anatomical structures and the risk of damage to the tricuspid valve must not be neglected. It is also concluded that valvuloplasty of the tricuspid valve can be successfully performed in a transplanted heart.

Sustained elevated concentrations of cardiac troponin T during acute allograft rejection after heart transplantation in children.

Background. The diagnosis of acute rejection after heart transplantation is made on the basis of endomyocardial biopsy. In children, where the method may be associated with complications, a noninvasive alternative would be desirable. We evaluated the myocardial damage marker cardiac troponin T (cTnT) as a marker of rejection in children who have undergone heart transplantation. Methods. Peripheral venous blood was collected in 124 endomyocardial biopsies in 14 children who had undergone heart transplantation (1–20 years of age). Serum levels of cTnT were compared with histologic rejection according to the International Society of Heart and Lung Transplantation (ISHLT) (grades 0–4). Results. Seven children experienced nine episodes of acute rejection. During rejection, cTnT increased from 0.05±0.07 (mean±SD) &mgr;g/L to 0.26±0.27 &mgr;g/L and remained elevated 7 and 30 days thereafter (0.10±0.11 and 0.36±0.38 &mgr;g/L, respectively) before returning to normal after 50 to 430 days. In surveillance biopsies, cTnT displayed considerable variation at all rejection grades: ISHLT grade 0, median 0.03 &mgr;g/L (range 0.01–2.04 &mgr;g/L); ISHLT grade 1, median 0.06 &mgr;g/L (range 0.01–0.67 &mgr;g/L); ISHLT grade 2, median 0.10 &mgr;g/L (range 0.01–1.42 &mgr;g/L); and ISHLT grade 3, median 0.17 &mgr;g/L (range 0.01–0.93 &mgr;g/L). A receiver operating characteristics analysis for cTnT versus rejection grade revealed an area under the curve of 0.69, indicating a moderate predictive value for cTnT. However, a cutoff of 0.015 &mgr;g/L yielded a specificity of only 36%, with a sensitivity of 89%, whereas a cutoff of 0.1 &mgr;g/L resulted in sensitivity and specificity of 53% and 77%, respectively. Conclusions. Cardiac troponin T increased and remained elevated for at least 1 month during acute rejection. The diagnostic power of a single cTnT measurement was not sufficient to replace endomyocardial biopsy.

Growth hormone alone or combined with metoprolol preserves cardiac function after myocardial infarction in rats

Beta‐adrenoreceptor blocking agents are important for the treatment of myocardial infarction (MI). Accumulating evidence also indicates that growth hormone (GH) improves cardiac function after MI in rats. We aimed to investigate the cardiovascular effects of combined treatment in an animal model of MI.

The origin of alveolar macrophages in the transplanted lung: a longitudinal microsatellite-based study of donor and recipient DNA

Transplanted lungs are initially populated by donor pulmonary alveolar macrophages (PAMs). These will form major antigen presenters for the recipients suppressed immune system. They may be expected to be replaced by recipient major histocompatibility complex-compatible cells, with time. We have isolated CD14+ PAMs from bronchoalveolar lavage specimens for 6 months after transplantation and identified their origin by using microsatellite analysis. This DNA-based technology permits the reliable identification of the origin of cells from different individuals. We show that replacement of donor PAMs occurs with individual dynamics in each case. Recipient PAMs usually appeared within 2 weeks, whereas donor cells could be retained for as long as 6 months. In this limited series, there was no obvious correlation between the dynamics of this process and the occurrence of rejection episodes or infections.

Yield of surveillance and diagnostic transbronchial lung biopsies (TBB) performed beyond one year after lung transplantation

Abstract Aim: To analyze the outcome of transbronchial lung biopsy (TBB) according to a standard follow-up protocol (protocol TBB), or, on clinical indications (diagnostic TBB) performed at least one year after lung transplantation. Methods: A retrospective review of all protocol and diagnostic TBBs beyond the first year after trans-plantation was conducted in patients transplanted between 1994 – 1999 at Sahlgrenska University Hospital (46 single lung, 26 double lung and 8 heart-lung tx). Results: A total of 357 TBBs were assessed in 80 patients during a follow-up between 1 - 6 years post transplant, 257 were protocol TBBs and the remaining 100 diagnostic TBBs. Protocol TBBs revealed histopathological findings in 26% of the procedures at 1-year follow-up, 17% at 2-year, 18% at 3-year and 8% at 4-year, whereas no findings appeared at 5 and 6-year follow up. Of the histopathological findings 77 % were acute rejection grade 1–2. Diagnostic TBBs were most common between the first and second year post transplant (n=66). Of all diagnostic TBBs, 63% revealed histopathology, they were mainly acute rejections grade 1–3 (31%), nonspecific inflammation (27%) and infections (19%). Conclusion: This study supports the usage of protocol TBB examinations during the first 3 years after lung transplantation. However, beyond this time interval, TBB may only be performed on clinical indications.