Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex and heterogeneous disease. Given this, we reasoned that differences in genetic profiles may be associated with unique clinical and radiologic features. Computational image analysis, sometimes referred to as radiomics, provides objective, quantitative assessments of radiologic features in subjects with pulmonary fibrosis. Objectives: To determine if the genetic risk profile of patients with IPF identifies unique computational imaging phenotypes. Methods: Participants with IPF were included in this study if they had genotype data and computed tomography (CT) scans of the chest available for computational image analysis. The extent of lung fibrosis and the likelihood of a usual interstitial pneumonia (UIP) pattern were scored automatically using two separate, previously validated deep learning techniques for CT analysis. UIP pattern was also classified visually by radiologists according to established criteria. Results: Among 329 participants with IPF, MUC5B and ZKSCAN1 were independently associated with the deep learning-based UIP score. None of the common variants were associated with fibrosis extent by computational imaging. We did not find an association between MUC5B or ZKSCAN1 and visually assessed UIP pattern. Conclusions: Select genetic variants are associated with computer-based classification of UIP on CT in this IPF cohort. Analysis of radiologic features using deep learning may enhance our ability to identify important genotype-phenotype associations in fibrotic lung diseases.

Since Familial Pulmonary Fibrosis (FPF) manifests in older adults and telomere attrition is common in FPF and sporadic Idiopathic Pulmonary Fibrosis (IPF), we postulated that accelerated aging, as determined by epigenetic clock (DNA methylation) measurements, could occur in FPF. We measured DNAge from blood of patients with FPF and a group of first-degree relatives of FPF patients without disease (termed “at-risk” for FPF) with or without genetic rare variants (RVs) in telomerase pathway genes. We observed accelerated epigenetic aging with increased DNAge compared to chronological age in individuals at-risk for FPF and FPF patients compared to healthy controls. We found that increased DNAge manifests independently of the presence of RVs in telomerase pathway genes or telomere length in peripheral blood cells. These findings suggest that increased DNAge could be an independent risk factor for the development of FPF. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement 5K12HD043483-12 P01HL172729 ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: These studies were approved by the Vanderbilt University Institutional Review Board (IRB# 020343, 080780). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors

Determining how alveoli are formed and maintained is critical to understanding lung organogenesis and regeneration after injury. To study the cellular dynamics of this critical stage of lung development, we have used scanned oblique-plane illumination microscopy of living lung slices to observe alveologenesis in real time at high resolution over several days. Contrary to the prevailing notion that alveologenesis occurs by airspace subdivision via ingrowing septa, we found that alveoli form by ballooning epithelial outgrowth supported by contracting mesenchymal ring structures. Systematic analysis has produced a computational model of finely timed cellular structural changes that drive normal alveologenesis. With this model, we can now quantify how perturbing known regulatory intercellular signaling pathways and cell migration processes affects alveologenesis. In the future, this paradigm and platform can be leveraged for mechanistic studies and screening for therapies to promote lung regeneration.

Reactivation and dysregulation of the mTOR signaling pathway are a hallmark of aging and chronic lung disease; however, the impact on microvascular progenitor cells (MVPCs), capillary angiostasis, and tissue homeostasis is unknown. While the existence of an adult lung vascular progenitor has long been hypothesized, these studies show that Abcg2 enriches for a population of angiogenic tissue-resident MVPCs present in both adult mouse and human lungs using functional, lineage, and transcriptomic analyses. These studies link human and mouse MVPC-specific mTORC1 activation to decreased stemness, angiogenic potential, and disruption of p53 and Wnt pathways, with consequent loss of alveolar-capillary structure and function. Following mTOR activation, these MVPCs adapt a unique transcriptome signature and emerge as a venous subpopulation in the angiodiverse microvascular endothelial subclusters. Thus, our findings support a significant role for mTOR in the maintenance of MVPC function and microvascular niche homeostasis as well as a cell-based mechanism driving loss of tissue structure underlying lung aging and the development of emphysema.

Introduction: Herpesviruses are ubiquitous viruses that establish latent infections and are present at high rates in individuals with Idiopathic pulmonary fibrosis (IPF). Animal models of pulmonary fibrosis using virus infection support the role of herpesvirus as potential source of microinjury to the lung epithelium. Objective: We aimed to understand whether prior herpesvirus infection (based on serology testing) is associated with differences in outcome of IPF progression. Methods: We performed Cytomegalovirus (CMV) and Epstein Bar Virus (EBV) serology analysis on 161 individuals with interstitial lung disease (ILD) enrolled in a longitudinal cohort. Pulmonary function testing [predicted force vital capacity (FVC)%], was performed at baseline and 1 year following enrollment. In addition, telomere length (TL) was measured in white blood cells by southern blot. Results: Among all participants, 90 were positive for CMV (53% females and 46% males), and 141 were positive for EBV (47% females and 52% males). In this cohort, female patients who were CMV+ or EBV+ were more often diagnosed with other ILDs (72%) when compared to IPF (28%). Male patients who were CMV+ or EBV+ males were more often diagnosed with IPF (65%) compared to other ILDs (35%). Changes in FVC% were not associated with CMV serostatus and the percentage of individuals with short telomere length (<1%) was similar in CMV+ and CMV- participants. Conclusions: Collectively, these data indicate that while CMV is present in high number of males with IPF, a history of CMV infection does not predict ILD progression. Methods capable to detect virus reactivation in situ are necessary to explore the contribution of CMV in disease progression.