Correlation of Broncho-Alveolar Lavage Cell Count and Pulmonary Function Tests in the Era of Antifibrotics: Data from the Belgium-Luxembourg IPF registry

peer reviewe

ERS International Congress 2021: highlights from the Interstitial Lung Diseases Assembly

This article provides an overview of scientific highlights in the field of interstitial lung disease (ILD), presented at the virtual European Respiratory Society Congress 2021. A broad range of topics was discussed this year, ranging from translational and genetic aspects to novel innovations with the potential to improve the patient pathway. Early Career Members summarise a selection of interesting findings from different congress sessions, together with the leadership of Assembly 12 - Interstitial Lung Disease. © The authors 2022

Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs

Life-threatening `breakthrough' cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS- CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals ( age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto- Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-a2 and IFN-., while two neutralized IFN-omega only. No patient neutralized IFN-ss. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population

Autoantibodies against type I IFNs in patients with critical influenza pneumonia

In an international cohort of 279 patients with hypoxemic influenza pneumonia, we identified 13 patients (4.6%) with autoantibodies neutralizing IFN-alpha and/or -omega, which were previously reported to underlie 15% cases of life-threatening COVID-19 pneumonia and one third of severe adverse reactions to live-attenuated yellow fever vaccine. Autoantibodies neutralizing type I interferons (IFNs) can underlie critical COVID-19 pneumonia and yellow fever vaccine disease. We report here on 13 patients harboring autoantibodies neutralizing IFN-alpha 2 alone (five patients) or with IFN-omega (eight patients) from a cohort of 279 patients (4.7%) aged 6-73 yr with critical influenza pneumonia. Nine and four patients had antibodies neutralizing high and low concentrations, respectively, of IFN-alpha 2, and six and two patients had antibodies neutralizing high and low concentrations, respectively, of IFN-omega. The patients' autoantibodies increased influenza A virus replication in both A549 cells and reconstituted human airway epithelia. The prevalence of these antibodies was significantly higher than that in the general population for patients 70 yr of age (3.1 vs. 4.4%, P = 0.68). The risk of critical influenza was highest in patients with antibodies neutralizing high concentrations of both IFN-alpha 2 and IFN-omega (OR = 11.7, P = 1.3 x 10(-5)), especially those <70 yr old (OR = 139.9, P = 3.1 x 10(-10)). We also identified 10 patients in additional influenza patient cohorts. Autoantibodies neutralizing type I IFNs account for similar to 5% of cases of life-threatening influenza pneumonia in patients <70 yr old

Higher COVID-19 pneumonia risk associated with anti-IFN-α than with anti-IFN-ω auto-Abs in children

We found that 19 (10.4%) of 183 unvaccinated children hospitalized for COVID-19 pneumonia had autoantibodies (auto-Abs) neutralizing type I IFNs (IFN-alpha 2 in 10 patients: IFN-alpha 2 only in three, IFN-alpha 2 plus IFN-omega in five, and IFN-alpha 2, IFN-omega plus IFN-beta in two; IFN-omega only in nine patients). Seven children (3.8%) had Abs neutralizing at least 10 ng/ml of one IFN, whereas the other 12 (6.6%) had Abs neutralizing only 100 pg/ml. The auto-Abs neutralized both unglycosylated and glycosylated IFNs. We also detected auto-Abs neutralizing 100 pg/ml IFN-alpha 2 in 4 of 2,267 uninfected children (0.2%) and auto-Abs neutralizing IFN-omega in 45 children (2%). The odds ratios (ORs) for life-threatening COVID-19 pneumonia were, therefore, higher for auto-Abs neutralizing IFN-alpha 2 only (OR [95% CI] = 67.6 [5.7-9,196.6]) than for auto-Abs neutralizing IFN-. only (OR [95% CI] = 2.6 [1.2-5.3]). ORs were also higher for auto-Abs neutralizing high concentrations (OR [95% CI] = 12.9 [4.6-35.9]) than for those neutralizing low concentrations (OR [95% CI] = 5.5 [3.1-9.6]) of IFN-omega and/or IFN-alpha 2

Dendritic cells in human asthma : regulation by TSLP and role in disease persistence

This thesis aimed at studying the role of dendritic cells in allergic asthma. In the first part of the work, we demonstrated that allergic asthmatics have a higher proportion of myeloid dendritic cells (mDC) expressing the receptor for thymic stromal lymphopoietin (TSLP), a pro-allergic epithelial cytokine, as compared to controls. This provides mDC from allergic asthmatics a particular propensity to induce Th2 and Th9 responses following stimulation with TSLP. In the second part of the work, we investigated the potential role of dendritic cell in asthma recovery. Indeed, although the natural history of asthma includes in some patients periods of disease remission, the underlying mechanisms are unknown. We studied myeloid dendritic cell functionality in a well-controlled setting, namely patients with occupational asthma with either remission or persistence following complete allergen avoidance. We showed that blood dendritic cells from patients with occupational asthma and persistent disease despite allergen avoidance are imprinted with pro-Th2 activity. All in all, this work contributes to a better understanding of dendritic cell biology in asthma, and further points to those cells and their environment as potential targets for future therapies in asthma.(MED - Sciences médicales) -- UCL, 201

Epithelial damage and remodeling in Idiopathic Pulmonary Fibrosis

Lung fibrosis is characterized by the progressive replacement of lung alveoli by a fibrotic scar tissue. The disease is considered as epithelial-derived: repeated lung injury or sustained inflammation leads to the destruction of alveolar epithelial cells, which reside at the forefront of the interface between lung and environment. This epithelial injury is followed by type 2 alveolar cell hyperplasia and dysfunction, along with the recapitulation of developmental pathways. Impaired cell differentiation is also a key characteristic of lung fibrosis, and the way the balance between epithelial repair and fibrosis is regulated still remains partially unexplained. Interestingly, epithelial remodeling and cell turnover provide opportunities for biomarkers. Finally, currently available drugs, as well as novel treatments, exert, at least partially, their function through epithelial cell regulation