Enhanced glucocorticoid-induced leucine zipper in dendritic cells induces allergen-specific regulatory CD4(+) T-cells in respiratory allergies.

BACKGROUND: Respiratory allergies rely on a defect of IL-10-secreting regulatory CD4(+) T-cells (IL-10-Tregs ) leading to excessive Th2-biased immune responses to allergens. According to clinical data, the restoration of allergen-specific IL-10-Tregs is required to control respiratory allergies and cure patients. The discovery of mechanisms involved in the generation of IL-10-Tregs will thus help to provide effective treatments. We previously demonstrated that dendritic cells (DCs) expressing high levels of the glucocorticoid-induced leucine zipper protein (GILZ) generate antigen-specific IL-10-Tregs . OBJECTIVE: We suspect a defective expression of GILZ in the DCs of respiratory allergic patients and speculate that increasing its expression might restore immune tolerance against allergens through the induction of IL-10-Tregs . METHODS: We assessed GILZ expression in blood DCs of patients and healthy nonallergic donors by qPCR. We compared the ability of patients' DCs to induce allergen-specific IL-10-Tregs before and after an in vivo up-regulation of GILZ expression by steroid administration, steroids being inducers of GILZ. RESULTS: We report lower levels of GILZ in DCs of respiratory allergic patients that return to normal levels after steroid administration. We show that patients' DCs with increased levels of GILZ generate allergen-specific IL-10-Tregs again. We further confirm unequivocally that GILZ is required in patients' DCs to activate these IL-10-Tregs . CONCLUSION: This proof of concept study shows that the re-establishment of GILZ expression in patients' DCs to normal levels restores their capacity to activate allergen-specific IL-10-Tregs . We thus highlight the up-regulation of GILZ in DCs as a new interventional approach to restore the immune tolerance to allergens.

[Pulmonary complications of Chronic Granulomatous Disease]. / Complications pulmonaires de la granulomatose septique chronique.

Chronic Granulomatosis Disease (CGD) is an inherited immune deficiency due to a mutation in the genes coding for the subunits of the NADPH oxidase enzyme that affects the oxidative capacity of phagocytic cells. It is characterized by increased susceptibility to bacterial and fungal infections, particularly Aspergillus, as well as complications associated with hyperinflammation and granulomatous tissue infiltration. There exist two types of frequently encountered pulmonary manifestations: (1) due to their being initially pauci-symptomatic, possibly life-threatening infectious complications are often discovered at a late stage. Though their incidence has decreased through systematic anti-bacterial and anti-fungal prophylaxis, they remain a major cause of morbidity and mortality; (2) inflammatory complications consist in persistent granulomatous mass or interstitial pneumoniae, eventually requiring immunosuppressive treatment. Pulmonary complications recurring since infancy generate parenchymal and bronchial sequelae that impact functional prognosis. Hematopoietic stem cell allograft is a curative treatment; it is arguably life-sustaining and may limit the morbidity of the disease. As a result of improved pediatric management, life expectancy has increased dramatically. That said, new challenges have appeared with regard to adults: difficulties of compliance, increased inflammatory manifestations, acquired resistance to anti-infectious therapies. These different developments underscore the importance of the transition period and the need for multidisciplinary management.

Dexamethasone reverses monocrotaline-induced pulmonary arterial hypertension in rats.

Pulmonary arterial hypertension (PAH) is associated with dysregulated bone morphogenetic protein receptor (BMPR)-II signaling and pulmonary vascular inflammation. We evaluated the effects of dexamethasone on monocrotaline (MCT)-induced PAH in rats for potential reversal of PAH at late time-points. Saline-treated control, MCT-exposed, MCT-exposed and dexamethasone-treated rats (5 mg·kg⁻¹·day⁻¹, 1.25 mg·kg⁻¹ and 2.5 mg·kg⁻¹·48 h⁻¹) were evaluated at day 28 and day 35 following MCT for haemodynamic parameters, right ventricular hypertrophy, morphometry, immunohistochemistry, and IL6 and BMPR2 expression. Dexamethasone improved haemodynamics and pulmonary vascular remodelling, preventing PAH development at early (day 1-14 and 1-28) and reversing PAH at late (day 14-28 and 21-35) time-points following MCT, as well as improving survival in MCT-exposed rats compared with controls. Both MCT-induced pulmonary IL6 overexpression and interleukin (IL)-6-expressing adventitial inflammatory cell infiltration were reduced with dexamethasone. This was associated with pulmonary BMPR2 downregulation following MCT, which was increased with dexamethasone, in whole lung and control pulmonary artery smooth muscle cells. Dexamethasone also reduced proliferation of rat pulmonary artery smooth muscle cells in vitro. Experimental PAH can be prevented and reversed by dexamethasone, and survival is improved. In this model, mechanisms may involve reduction of IL-6-expressing inflammatory cells, restoration of pulmonary BMPR2 expression and reduced proliferation of vascular smooth muscle cells.

[Postembolic pulmonary hypertension]. / Hypertension pulmonaire postembolique.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease characterized by the persistence of thromboemboli obstructing the pulmonary arteries as an organized tissue. The consequence is an increase in pulmonary vascular resistance resulting in pulmonary hypertension (PH) and progressive right heart failure. BACKGROUND: It is difficult to recognize the postembolic nature of PH because there is no known history of thromboembolic disease in more than 50% of cases. Diagnosis is based on the presence of mismatched segmental defects in the ventilation-perfusion scanning. When CTEPH is suspected, pulmonary angiography and high-resolution CT scan are required to establish the diagnosis and to assess the operability. Pulmonary angiography is always performed in conjunction with a diagnostic right heart catheterization, which is required to confirm the diagnosis of PH and to determine the degree of hemodynamic impairement. If there is a good correlation between the pulmonary vascular resistance and the anatomical obstruction, pulmonary endarterectomy (PEA) must be proposed. Otherwise, vasodilator and antiproliferative treatments and lung transplantation represent interesting alternatives. VIEWPOINT AND CONCLUSION: PEA remains the treatment of choice for eligible patients. Nevertheless, there is a need to conduct randomized trials to assess the efficacy of novel medical therapies in some situations: (1) in inoperable CTEPH due to distal lesions, (2) before PEA (therapeutic bridge) in patients who are considered "high risk" due to extremely poor hemodynamics, (3) in patients with persistent pulmonary hypertension after surgery.

Efficacy and safety of gefitinib during pregnancy: case report and literature review.

The incidence of lung cancer is rising in pregnancy, which is diagnosed on stage III-IV in 98%. Almost half of these patients are non-smokers, who are associated with more epidermal growth factor receptor (EGFR)-mutated lung cancer. As cytotoxic chemotherapy is associated with poor outcome for mothers and prematurity for children this will probably lead to repeatedly question the use of EGFR-Tyrosine kinase inhibitors (TKI) (i.e. gefitinib and erlotinib) during pregnancy for EGFR-mutated lung cancer. EGFR-TKIs are recommended as the first line targeted therapy in case of advanced non small cell lung carcinoma (NSCLC) with an activating EGFR mutation but not recommended during pregnancy due to lack of data. We report clinical and pharmacological data for gefitinib during pregnancy in both the mother and fetus and resume the literature on the subject. A 33-year-old pregnant mother exhibited a disseminated EGFR-mutated lung carcinoma with respiratory distress at 26 weeks of pregnancy. Gefitinib administration was associated with rapid maternal respiratory improvement allowing a planned cesarian section on week 35, giving birth to a healthy baby (2575g) with regular development at 24 months of follow-up. The mother exhibited a progression-free survival of 42 weeks with an overall survival of 22 months. Gefitinib residual concentration was found in cord blood at 25.7ng/mL, confirming a transplacental transfer, but at only 20% of the maternal concentration measured at the same time (i.e. 127.1ng/mL). Gefitinib concentration in amniotic fluid, which represents chronic fetal exposure to the drug, was also 20% of the maternal residual concentration (16.9ng/mL) and reflected no fetal accumulation of the drug, despite both long half time elimination of gefitinib (i.e. 48h) and long time exposure (i.e. 55 days). This low transplacental transfer is an important report, as potential side effect toxicity on the fetus is likely correlated to gefitinib blood concentration.

[Pulmonary arterial hypertension related to HIV: is inflammation related to IL-6 the cornerstone?]. / Hypertension artérielle pulmonaire liée à l'infection VIH : de la pression artérielle pulmonaire à l'interleukine-6.

Vascular diseases have become the leading cause of mortality in the population treated for HIV infection. Pulmonary arterial hypertension (PAH) related to HIV (PAH-HIV), the fourth cause of PAH in France, has the same histological pattern as other PAH from the group 1 of Dana Point classification. But, conversely to idiopathic PAH in the general population, PAH-HIV is particular by its high frequency in HIV-infected population. This raises the question for the role of inflammation in the PAH-HIV pathophysiology. Its constant occurrence over the decades, despite introduction of combination antiretroviral therapy (CAT), does not preclude the hypothesis of an involvement of inflammation in the genesis of PAH-HIV. Indeed, it is well known that normalization of CD4+ by the CAT does not mean no inflammation. Especially, it persists an increased and continuous production of IL-6, a main cytokine in the genesis of PAH lesions. This inflammation mainly involves the endothelin-1 pathway, which has an action on endothelium and macrophages, leading to high production of IL-6. Moreover, plasmatic level of IL-6 has a prognostic value in PAH-HIV, independently from conventional (functional or hemodynamic) parameters. The use of endothelin receptor antagonist permits major effect on IL-6 production and dramatic effect on PAH in so-called "bosentan responders".

[Are investigations for underlying causes needed for the management of an adult patient with bronchiectasis?]. / La recherche d'une étiologie est-elle nécessaire à la prise en charge d'un adulte ayant une dilatation des bronches ?

Bronchiectasis may result from various causes. Recognition of these underlying causes may lead to specific management. Focal bronchiectasis are related to luminal blockage or extrinsic narrowing. The causative factors of diffuse bronchiectasis may be suggested by the predominant distribution of the disease and associated extrapulmonary manifestations. Primary immunodeficiencies cystic fibrosis, allergic bronchopulmonary aspergillosis, chronic Mycobacterium avium complex infection, and systemic diseases have to be looked for, even in patients with knowledge of a childhood respiratory infection.

[Pulmonary cystic adenomatoid malformation in an adult patient: an underdiagnosed disease]. / Malformation kystique adénomatoïde pulmonaire de l'adulte : une pathologie méconnue.

Currently, most congenital lower respiratory tract malformations are detected during pregnancy or at birth, thanks to antenatal imaging. However, a pulmonary congenital cystic adenomatoid disease may be found in adulthood. The diagnosis is difficult, due to its rarity. We present the case of a patient whose diagnosis of pulmonary cystic adenomatoid malformation was confirmed when she had tuberculosis. A lobectomy was performed, which enabled identification of tuberculosis and also multiple cysts of adenomatoid malformation. The risk posed by this malformation, i.e. the risk of developing bronchioloalveolar carcinoma and of infection or pneumothorax, is the incentive for proposing formal surgical removal.

[Bronchiolitis obliterans postallogeneic stem cell transplantation: what is new?]. / Bronchiolite oblitérante après allogreffe de cellules souches hématopoïétiques : quels progrès ?

Bronchiolitis obliterans (BO) is a severe complication of hematopoietic stem cell transplantation (HSCT). It is considered as a respiratory manifestation of chronic graft-versus-host disease. It is quite similar to the bronchiolitis obliterans after lung transplantation. Classical therapy associates steroids and immunosuppressive drugs, however theses procedure showed a modest efficacy and have an important morbidity. Recent progresses in the physiopathology of BO post-HSCT allow to use new treatments: mTOR inhibitors, immunotherapy, extra-corporeal photochemotherapy, and bronchial anti-inflammatory effects of azithromycin, statins or antileucotriens. This review will focus on the use of these new therapies in BO post-HSCT.