In Vivo and In Vitro Pro-Fibrotic Response of Lung-Resident Mesenchymal Stem Cells from Patients with Idiopathic Pulmonary Fibrosis.

Lung-resident mesenchymal stem cells (LR-MSC) are thought to participate in idiopathic pulmonary fibrosis (IPF) by differentiating into myofibroblasts. On the other hand, LR-MSC in IPF patients present senescence-related features. It is unclear how they respond to a profibrotic environment. Here, we investigated the profibrotic response of LR-MSC isolated from IPF and control (CON) patients. LR-MSC were inoculated in mice 48 h after bleomycin (BLM) instillation to analyze their contribution to lung damage. In vitro, LR-MSC were exposed to TGFß. Mice inoculated with IPF LR-MSC exhibited worse maintenance of their body weight. The instillation of either IPF or CON LR-MSC sustained BLM-induced histological lung damage, bronchoalveolar lavage fluid cell count, and the expression of the myofibroblast marker, extracellular matrix (ECM) proteins, and proinflammatory cytokines in the lungs. In vitro, IPF LR-MSC displayed higher basal protein levels of aSMA and fibronectin than CON LR-MSC. However, the TGFß response in the expression of TGFß, aSMA, and ECM genes was attenuated in IPF LR-MSC. In conclusion, IPF LR-MSC have acquired myofibroblastic features, but their capacity to further respond to profibrotic stimuli seems to be attenuated. In an advanced stage of the disease, LR-MSC may participate in disease progression owing to their limited ability to repair epithelial damage.

Mesenchymal Stem Cells from COPD Patients Are Capable of Restoring Elastase-Induced Emphysema in a Murine Experimental Model.

COPD is a chronic lung disease that affects millions of people, declining their lung function and impairing their life quality. Despite years of research and drug approvals, we are still not capable of halting progression or restoring normal lung function. Mesenchymal stem cells (MSC) are cells with extraordinary repair capacity, and MSC-based therapy brings future hope for COPD treatment, although the best source and route of administration are unclear. MSC from adipose tissue (AD-MSC) represents an option for autologous treatment; however, they could be less effective than donor MSC. We compared in vitro behavior of AD-MSC from COPD and non-COPD individuals by migration/proliferation assay, and tested their therapeutic potential in an elastase mouse model. In addition, we tested intravenous versus intratracheal routes, inoculating umbilical cord (UC) MSC and analyzed molecular changes by protein array. Although COPD AD-MSC have impaired migratory response to VEGF and cigarette smoke, they were as efficient as non-COPD in reducing elastase-induced lung emphysema. UC-MSC reduced lung emphysema regardless of the administration route and modified the inflammatory profile in elastase-treated mice. Our data demonstrate equal therapeutic potential of AD-MSC from COPD and non-COPD subjects in the pre-clinical model, thus supporting their autologous use in disease.

Report of a case of RAVEN, hair heterochromia and autism in the setting of FGFR2 mutation.

A newborn presented with extensive rounded and velvety epidermal nevus (RAVEN) with a genetic study of the cutaneous lesions revealing a heterozygous mutation in FGFR2 (p.Cys382Arg). By 2 years of age, the patient developed hair heterochromia and autism spectrum disorder. Although RAVEN was initially associated with fibroblast growth factor 3 (FGFR3) mutations, three cases of RAVEN have been identified with mutations in FGFR2 (p.Ser252Trp) and one case of linear keratinocytic epidermal nevi has been identified with the same mutation as the mutation identified in our patient. This strongly supports the pathogenic role of these mutations.

Pulmonary nodular lymphoid hyperplasia and Sjögren's syndrome: a case report and literature review.

Pulmonary nodular lymphoid hyperplasia, also known as pseudolymphoma, is an uncommon reactive lymphoproliferative disorder of unknown etiology that can be found in Sjögren's syndrome patients. Here, we present a case of a previously healthy woman in which the incidental finding of a lung mass compatible with nodular lymphoid hyperplasia led to the subsequent diagnosis of Sjögren's syndrome. We also performed a literature review for the association between both entities and described the main clinical aspects of the reported cases. Although its rarity, we consider that pulmonary nodular lymphoid hyperplasia should be considered in the differential diagnosis of lung nodules or masses among Sjögren's syndrome patients.

Detection of the EGFR G719S Mutation in Non-small Cell Lung Cancer Using Droplet Digital PCR.

Objectives: The main objectives of the study were (1) to set-up a droplet digital PCR (ddPCR) assay for the non-invasive detection of G719S EGFR mutation in NSCLC patients; (2) to determine the limits of detection of the ddPCR assay for G719S mutation and (3) to compare COBAS® and ddPCR System for G719S quantification in plasma. Materials and Methods: Blood samples were collected from 22 patients diagnosed with advanced NSCLC. Then, plasma ctDNA was extracted with the Qiagen Circulating Nucleic Acids kit and quantified by QuantiFluor® dsDNA System. The mutational study of EGFR was carried out by digital droplet PCR (ddPCR) with the QX200 Droplet Digital PCR System with specific probes and primers. Results: We observed the lowest percentage of G719S mutant allele could be detected in a wildtype background was 0.058%. In the specificity analysis, low levels of G719S mutation were detected in healthy volunteers with a peak of 21.65 mutant copies per milliliter of plasma and 6.35 MAFs. In those patients whose tissue biopsy was positive for G719S mutation, mutant alleles could also be detected in plasma using both ddPCR and COBAS® System. Finally, when mutational status was studied using both genotyping techniques, higher mutant copies/ml and higher mutant allele fraction (MAF) correlated with higher Semiquantitative Index obtained by COBAS®. Conclusions: Although tissue biopsies cannot be replaced due to the large amount of information they provide regarding tumor type and structure, liquid biopsy and ddPCR represents a new promising strategy for genetic analysis of tumors from plasma samples. In the present study, G719S mutation was detected in a highly sensitive manner, allowing its monitorization with a non-invasive technique.

Serosal involvement in IgG4-related disease: report of two cases and review of the literature.

IgG4-related disease (IgG4-RD) is a recently described entity characterized by lymphoplasmacytic infiltrates, usually mimicking tumors, affecting almost every organ or system. Nevertheless, serosal involvement has been rarely reported. In this article, we report two cases of IgG4-RD with serosal involvement and review the literature. Because of the varied clinical pictures found in our review, we suggest a new terminology for the description of IgG4-RD with serosal involvement.