Airway wall remodeling in allergic asthma is reduced after treatment with humanized anti-IgE-antibodies. We reported earlier that purified IgE, without the presence of allergens, is sufficient to ...induce airway wall remodeling due to airway smooth muscle cell (ASMC) activity deposing extracellular matrix.
We postulate that IgE contained in serum of allergic asthma patients, in the absence of allergens, stimulates ASMC remodeling activities and can be prevented by anti-IgE antibodies.
Isolated human ASMC were exposed to serum obtained from: (i) healthy controls, or patients with (ii) allergic asthma, (iii) non-allergic asthma, and (iv) atopic non-asthma patients. Proliferation and the deposition of collagens and fibronectin were determined after 3 and 5 days.
Serum from patients with allergies significantly stimulated: (i) ASMC proliferation, (ii) deposition of collagen type-I (48 hours) and (iii) of fibronectin (24 hours). One hour pre-incubation with Omalizumab prevented these three effects of allergic serum, but had no significant effect on serum from healthy donors or non-allergic asthma patients. Interestingly, the addition of allergens did not further increase any of the IgE effects.
Our data provides experimental evidence that the beneficial effect of Omalizumab on airway wall remodeling and improved lung function may be due to its direct action on IgE bound ASMC.
Natural killer (NK) cells are critically involved in anti-tumor immunity by targeting tumor cells. In this study, we show that intratumoral NK cells from NSCLC patients expressed elevated levels of ...the immune checkpoint receptor PD-1 on their cell surface. In contrast to the expression of activating receptors, PD-1
+
NK cells co-expressed more inhibitory receptors compared to PD-1
−
NK cells. Intratumoral NK cells were less functional compared to peripheral NK cells, and this dysfunction correlated with PD-1 expression. Tumor cells expressing PD-L1 inhibited the functionality of PD-1
+
NK cells in ex vivo models and induced PD-1 clustering at the immunological synapse between NK cells and tumor cells. Notably, treatment with PD-1 blockade was able to reverse PD-L1-mediated inhibition of PD-1
+
NK cells. Our findings highlight the therapeutic potential of PD-1
+
NK cells in immune checkpoint blockade and could guide the development of NK cell-stimulating agents in combination with PD-1 blockade.
Background In asthma remodeling airway smooth muscle cells (ASMCs) contribute to airway wall thickness through increased proliferation, migration, and extracellular matrix deposition. Previously, we ...described that protein arginine methyltransferase 1 (PRMT1) participates in airway remodeling in pulmonary inflammation in E3 rats. Objective We sought to define the asthma-specific regulatory mechanism of PRMT1 in human ASMCs. Methods ASMCs from healthy subjects and asthmatic patients were activated with platelet-derived growth factor (PDGF)–BB. PRMT1 was localized by means of immunohistochemistry in human lung tissue sections and by means of immunofluorescence in isolated ASMCs. PRMT1 activity was suppressed by the pan-PRMT inhibitor AMI-1, signal transducer and activator of transcription 1 (STAT1) was suppressed by small interfering RNA, and extracellular signal-regulated kinase (ERK) 1/2 mitogen-activated protein kinase (MAPK) was suppressed by PD98059. MicroRNAs (miRs) were assessed by using real-time quantitative PCR and regulated by miR mimics or inhibitors. Results PRMT1 expression was significantly increased in lung tissue sections and in isolated ASMCs of patients with severe asthma. PDGF-BB significantly increased PRMT1 expression through ERK1/2 MAPK and STAT1 signaling in control ASMCs, whereas in ASMCs from asthmatic patients, these proteins were constitutively expressed. ASMCs from asthmatic patients had reduced miR-19a expression, causing upregulation of ERK1/2 MAPK, STAT1, and PRMT1. Inhibition of PRMT1 abrogated collagen type I and fibronectin deposition, cell proliferation, and migration of ASMCs from asthmatic patients. Conclusions PRMT1 is a central regulator of tissue remodeling in ASMCs from asthmatic patients through the pathway: PDGF-BB–miR-19a–ERK1/2 MAPK and STAT1. Low miR-19a expression in ASMCs from asthmatic patients is the key event that results in constitutive increased PRMT1 expression and remodeling. Therefore PRMT1 is an attractive target to limit airway wall remodeling in asthmatic patients.
Stem cells have been identified in the human lung; however, their role in lung disease is not clear. We aimed to isolate mesenchymal stem cells (MSC) from human lung tissue and to study their in ...vitro properties.
MSC were cultured from lung tissue obtained from patients with fibrotic lung diseases (n = 17), from emphysema (n = 12), and normal lungs (n = 3). Immunofluorescence stainings were used to characterize MSC. The effect of MSC-conditioned media (MSC-CM) on fibroblast proliferation and on lung epithelial wound repair was studied.
Expression of CD44, CD90, and CD105 characterized the cells as MSC. Moreover, the cells stained positive for the pluripotency markers Oct3/4 and Nanog. Positive co-stainings of chemokine receptor type 4 (CXCR4) with CD44, CD90 or CD105 indicated the cells are of bone marrow origin. MSC-CM significantly inhibited the proliferation of lung fibroblasts by 29% (p = 0.0001). Lung epithelial repair was markedly increased in the presence of MSC-CM (+ 32%). Significantly more MSC were obtained from fibrotic lungs than from emphysema or control lungs.
Our study demonstrates enhanced numbers of MSC in fibrotic lung tissue as compared to emphysema and normal lung. The cells inhibit the proliferation of fibroblasts and enhance epithelial repair in vitro. Further in vivo studies are needed to elucidate their potential role in the treatment of lung fibrosis.
Tumor-specific T cells are frequently exhausted by chronic antigenic stimulation. We here report on a human antigen-specific ex vivo model to explore new therapeutic options for T cell ...immunotherapies. T cells generated with this model resemble tumor-infiltrating exhausted T cells on a phenotypic and transcriptional level. Using a targeted pooled CRISPR-Cas9 screen and individual gene knockout validation experiments, we uncover sorting nexin-9 (SNX9) as a mediator of T cell exhaustion. Upon TCR/CD28 stimulation, deletion of SNX9 in CD8 T cells decreases PLCγ1, Ca
, and NFATc2-mediated T cell signaling and reduces expression of NR4A1/3 and TOX. SNX9 knockout enhances memory differentiation and IFNγ secretion of adoptively transferred T cells and results in improved anti-tumor efficacy of human chimeric antigen receptor T cells in vivo. Our findings highlight that targeting SNX9 is a strategy to prevent T cell exhaustion and enhance anti-tumor immunity.
The widely accepted and still increasing use of video-assisted thoracic surgery (VATS) in pleuro-pulmonary pathology imposes the need to deal with two major pitfalls: the first is to avoid its ...unselective use, while the second relates to inappropriate rejection of VATS on the basis of "insufficient radicality". Unlike a quite established role of VATS in lung cancer patients, in patients with pleural empyema, the role of VATS is less clearly defined. The current evidence about VATS in patients with pleural empyema could be summarised as follows: VATS is accepted as a useful treatment option for fibrinopurulent empyema, but the treatment failure rate increases with the increasing proportion of stage III empyema, necessitating further surgical options like thoracotomy and decortication. As both pulmonologists and surgeons deal with diagnosis and treatment of pleural empyema, this article is an attempt to highlight the existing evidence in a more user-friendly way in order to help practising physicians to optimise the use of VATS in these patients. In other words, in the absence of randomised studies comparing VATS and thoracotomy, the key question to be answered is: are there any pre-operative findings that can be used to select patients for initial VATS
proceeding directly to a thoracotomy?
Cancer immunotherapy with antibodies targeting immune checkpoints such as the PD-1/PD-L1 pathway have emerged as breakthrough treatment for multiple solid tumors with high response rates and durable ...remissions. Despite the benefit for patients and encouraging safety profile, severe inflammatory reactions are observed in some patients. Such immune-related adverse events (irAEs) frequently lead to temporary or permanent cessation of the treatment and require systemic immunosuppression yet underlying mechanisms of irAEs are not known in detail. Here, we describe the T cell-mediated immune reaction in irAE lesions of four patients that developed pneumonitis during therapy with a PD-1 blocking antibody. Immunohistochemical analysis was performed to map the environment of the inflammatory lesions. Tumor infiltrating T cell clones were identified by sequencing the T cell receptor, and comparison with clones from peripheral blood or secondary lymphoid organs. A significant overlap of clones infiltrating irAE lesions and tumors was found. The most prevalent clones were also expanded in peripheral blood, but only a minor fraction of clonal overlap was found. Our findings suggest that irAE lesions in patients under PD-1 blockade are infiltrated by T cells with similar specificity as tumor-infiltrating T cells. These results raise the possibility that the immune response is elicited in these patients against antigens shared by the tumor and distant organs affected by irAEs.
PD-L1, as assessed by immunohistochemistry, is a predictive biomarker for immuno-oncology treatment in lung cancer. Different scoring methods have been used to assess its status, resulting in a wide ...range of positivity rates. We use the European Thoracic Oncology Platform Lungscape non-small cell lung carcinoma cohort to explore this issue. PD-L1 expression was assessed via immunohistochemistry on tissue microarrays (up to four cores per case), using the DAKO 28-8 immunohistochemistry assay, following a two-round external quality assessment procedure. All samples were analyzed under the same protocol. Cross-validation of scoring between tissue microarray and whole sections was performed in 10% randomly selected samples. Cutoff points considered: ≥1, 50 (primarily), and 25%. At the two external quality assessment rounds, tissue microarray scoring agreement rates between pathologists were: 73% and 81%. There were 2008 cases with valid immunohistochemistry tissue microarray results (50% all cores evaluable). Concordant cases at 1, 25, and 50% were: 85, 91, and 93%. Tissue microarray core results were identical for 70% of cases. Sensitivity of the tissue microarray method for 1, 25, and 50% was: 80, 78, and 79% (specificity: 90, 95, 98%). Complete agreement between tissue microarrays and whole sections was achieved for 60% of the cases. Highest sensitivity rates for 1% and 50% cutoffs were detected for higher number of cores. Underestimation of PD-L1 expression on small samples is more common than overestimation. We demonstrated that classification of PD-L1 on small biopsy samples does not represent the overall expression of PD-L1 in all non-small cell cancer carcinoma cases, although the majority of cases are 'correctly' classified. In future studies, sampling more and larger biopsies, recording the biopsy size and tumor load may permit further refinement, increasing predictive accuracy.
Antibody-drug conjugates (ADC) are emerging as powerful treatment strategies with outstanding target-specificity and high therapeutic activity in patients with cancer. Brentuximab vedotin represents ...a first-in-class ADC directed against CD30(+) malignancies. We hypothesized that its sustained clinical responses could be related to the stimulation of an anticancer immune response. In this study, we demonstrate that the dolastatin family of microtubule inhibitors, from which the cytotoxic component of brentuximab vedotin is derived, comprises potent inducers of phenotypic and functional dendritic cell (DC) maturation. In addition to the direct cytotoxic effect on tumor cells, dolastatins efficiently promoted antigen uptake and migration of tumor-resident DCs to the tumor-draining lymph nodes. Exposure of murine and human DCs to dolastatins significantly increased their capacity to prime T cells. Underlining the requirement of an intact host immune system for the full therapeutic benefit of dolastatins, the antitumor effect was far less pronounced in immunocompromised mice. We observed substantial therapeutic synergies when combining dolastatins with tumor antigen-specific vaccination or blockade of the PD-1-PD-L1 and CTLA-4 coinhibitory pathways. Ultimately, treatment with ADCs using dolastatins induces DC homing and activates cellular antitumor immune responses in patients. Our data reveal a novel mechanism of action for dolastatins and provide a strong rationale for clinical treatment regimens combining dolastatin-based therapies, such as brentuximab vedotin, with immune-based therapies.
Objective Postpneumonectomy empyema remains a clinical challenge. We proposed an accelerated therapy without an open chest window 5 years ago. This concept was evaluated on a larger scale in 2 ...centers in 2 different countries. Methods Between July 1995 and October 2005, 75 consecutive patients with postpneumonectomy empyema were treated in Szczecin, Poland (n = 35), and Zurich, Switzerland (n = 40). The therapy consisted of repeated open surgical debridement of the pleural cavity after achievement of general anesthesia, a negative pressure wound therapy of the temporarily closed chest cavity filled with povidone-iodine–soaked towels, and continuous suction and systemic antimicrobial therapy. If present, bronchopleural fistulae were closed and reinforced either with a muscle flap or the omentum. Finally, the pleural space was filled with an antibiotic solution and definitively closed. Results Of 75 patients (63 men; median age, 59 years; age range, 19–82 years), postpneumonectomy empyema was present on the right in 46 patients (32 with bronchopleural fistula) and in 29 patients (12 with bronchopleural fistula) on the left. Median time between pneumonectomy and postpneumonectomy empyema was 131 days (range, 7–7200 days). Bronchopleural fistulae have been closed and additionally reinforced by means of different methods (omentum, 18; muscle, 11; pericardial fat, 5; azygos vein, 1). The chest was definitively closed within 8 days in 94.6% of patients. The median hospitalization time was 18 days (range, 9–134 days). Postpneumonectomy empyema was successfully treated in 97.3% of patients, including 10 (13%) patients who needed a second treatment cycle. Three (4%) patients died within 90 days. The median follow-up time was 29.5 moths (range, 3–107 months). Conclusions Treatment of postpneumonectomy empyema with the accelerated treatment is effective and safe. Our results are superior compared with those in reported series using a (temporary) chest fenestration. Patients appreciate the physical integrity of the chest.
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