Biology subjects

Byers, D. E.

Publications and source records attributed to Byers, D. E..

7 recordsLinked to original sources

bioRxiv2025

HSP70 is a chaperone for IL-33 secretion and function in chronic airway disease

IL-33 is a key driver of type 2 inflammation relevant to airway epithelial biology. However, the mechanisms for IL-33 secretion and regulation in the context of chronic airway disease is poorly understood. Here we report a disease-associated isoform IL-33{Delta}34 that escapes nuclear sequestration to be tonically secreted by recruitment to unconventional protein secretory pathways by HSP70. IL-33{Delta}34 interacts with HSP70 within cells to be targeted to secretory organelles through coordinated binding to phosphatidylserine (PS). Once secreted, this HSP70/cytokine complex stabilizes IL-33{Delta}34 by inhibiting oxidation/degradation thereby enhancing IL-33{Delta}34-receptor binding and activity. We find evidence for IL-33, HSP70 and chaperonin TCP-1 are dysregulated in human chronic airway disease. This phenomenon is reflected in differential proteomics of diseased bronchial wash extracellular vesicles. This study confirms proteostasis intermediates, chiefly HSP70, as a chaperone for non-canonical IL-33{Delta}34 secretion and activity that may be amenable for therapeutic targeting in airway diseases such as asthma and COPD. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=140 SRC="FIGDIR/small/635799v2_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@b01ea9org.highwire.dtl.DTLVardef@ad18c9org.highwire.dtl.DTLVardef@364c0forg.highwire.dtl.DTLVardef@bba135_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2024

Impaired complement regulation drives chronic lung allograft dysfunction after lung transplantation.

A greater understanding of chronic lung allograft dysfunction (CLAD) pathobiology, the primary cause of mortality after lung transplantation, is needed to improve outcomes. The complement system links innate to adaptive immune responses and is activated early post-lung transplantation to form the C3 convertase, a critical enzyme that cleaves the central complement component C3. We hypothesized that LTx recipients with a genetic predisposition to enhanced complement activation have worse CLAD-free survival mediated through increased adaptive alloimmunity. We interrogated a known functional C3 polymorphism (C3R102G) that increases complement activation through impaired C3 convertase inactivation in two independent LTx recipient cohorts. C3R102G, identified in at least one out of three LTx recipients, was associated with worse CLAD-free survival, particularly in the subset of recipients who developed donor-specific antibodies (DSA). In a mouse orthotopic lung transplantation model, impaired recipient complement regulation resulted in more severe obstructive airway lesions when compared to wildtype controls, despite only moderate differences in graft-infiltrating effector T cells. Impaired complement regulation promoted the intragraft accumulation of memory B cells and antibody-secreting cells, resulting in increased DSA levels. In summary, genetic predisposition to complement activation is associated with B cell activation and worse CLAD-free survival. BRIEF SUMMARYLung transplant recipients genetically predisposed to impaired complement regulation demonstrate worse chronic rejection-free survival. This phenotype is associated with intragraft B cell-activation and donor-specific antibodies.

immunology↗

bioRxiv2024

A first-in-kind MAPK13 inhibitor that can correct stem cell reprogramming and post-injury disease

The stress kinase MAPK13 (aka p38delta-MAPK) is an attractive entry point for therapeutic intervention because it regulates the structural remodeling that can develop after epithelial injury in the lung and likely other tissue sites. However, a selective, safe, and effective MAPK13 inhibitor is not yet available for experimental or clinical application. Here we identify a first-in-kind MAPK13 inhibitor using structure-based drug design combined with a screening funnel for cell safety and molecular specificity. In a mouse model of severe respiratory viral infection, treatment with this inhibitor (formulated as NuP-4A for intravenous use or Nu4-B for inhaled delivery) did not influence recovery from acute infectious illness, but still down-regulated basal-epithelial stem cell (basal-ESC) hyperplasia/metaplasia and in turn airway inflammation, mucus production, and pathophysiology biomarkers of chronic lung disease. Treatment prevented and reversed disease readouts equivalently to Mapk13 gene-knockout, and this benefit persisted after stopping treatment as a sign of disease modification. Further, NuP-4 treatment even at pM levels directly blocked basal-ESC reprogramming endpoints in organoid and cell-culture models derived from non-disease control and asthma subjects. The results thereby provide a new tool compound and drug candidate for basal-ESC reprogramming towards muco-obstructive lung diseases like asthma and any overlap with COPD and related diseases that depend on overactivity of MAPK13.

immunology↗

bioRxiv2024

Characteristics of human donor lungs utilized for research

IntroductionMany fundamental discoveries have occurred using primary cells from deceased donor lungs. These cells respond differently to injury when there are underlying co-morbidities like diabetes mellitus, hypertension, aging and exposures to cigarette smoke, cocaine and chronic alcohol use. However, the prevalence of these characteristics in donor lungs utilized for research is currently unknown. MethodsThis retrospective cohort study procured data of lung transplant donors from Mid-America Transplant from January 2017 until July 2023. The donors were characterized based on lung utilization into three groups - lungs used for research, lungs used for transplant, and lungs not recovered from donors for either research or transplantation. ResultsThe mean age of donors whose lungs were utilized for research was 41{+/-}18 years. 25% of them were expanded criteria donors (ECD) while 10% of the donors in the transplant cohort were ECD. 14% of the donors whose lungs were utilized for research had history of diabetes compared to 8% of donors whose lungs were transplanted. A quarter of the research donor population had positive history of cigarette use within the preceding 20 years. At least 40% of donors had a positive history of non-intravenous drug use, of whom a majority had a history of continued non-intravenous drug use. ConclusionsNo strict selection criteria or protocols exist when human donor lungs are obtained for ex-vivo research. There is a high prevalence of diabetes mellitus, history of smoking and non-intravenous drug use along with older age distribution in donors whose lungs used are for research.

immunology↗

bioRxiv2024

MAPK13 controls structural remodeling and disease after epithelial injury

All living organisms are charged with repair after injury particularly at epithelial barrier sites, but in some cases this response leads instead to structural remodeling and long-term disease. Identifying the molecular and cellular control of this divergence is key to disease modification. In that regard, stress kinase control of epithelial stem cells is a rational entry point for study. Here we examine the potential for mitogen-activated protein kinase 13 (MAPK13) regulation of epithelial stem cells using models of respiratory viral injury and post-viral lung disease that resembles asthma. We show that Mapk13 gene-knockout mice handle acute infectious illness as expected but are protected against basal-epithelial stem cell (basal-ESC) hyperplasia and mucous metaplasia. In corresponding organoid models, Mapk13-deficiency directly controls the basal-ESC program for stemness endpoints of hyperplasia and mucous metaplasia. Extension to human studies shows induction/activation of MAPK13 in basal-epithelial cells in lung tissue samples from asthma and COPD patients. Further, in human organoid models, MAPK13 mRNA knockdown regulates basal-ESC stemness similarly to mouse models. Together, the data identify MAPK13 as a control point for structural remodeling after epithelial injury and a suitable target for down-regulation as a disease-modifying strategy.

immunology↗

bioRxiv2023

A new MAPK13-guided inhibitor for respiratory inflammation and mucus production

Common respiratory diseases continue to represent a major public health problem, and much of the morbidity and mortality is due to airway inflammation and mucus production. Previous studies indicated a role for mitogen-activated protein kinase 14 (MAPK14) in this type of disease, but clinical trials are unsuccessful to date. Our previous work identified a related but distinct kinase known as MAPK13 that is activated in respiratory airway diseases and is required for mucus production in human cell-culture models. Support for MAPK13 function in these models came from effectiveness of MAPK13 versus MAPK14 gene-knockdown and from first-generation MAPK13-14 inhibitors. However, these first-generation inhibitors were incompletely optimized for blocking activity and were untested in vivo. Here we report the next generation and selection of a potent MAPK13-14 inhibitor (designated NuP-3) that more effectively down-regulates type-2 cytokine-stimulated mucus production in air-liquid interface and organoid cultures of human airway epithelial cells. We also show that NuP-3 treatment prevents respiratory airway inflammation and mucus production in new minipig models of airway disease triggered by type-2 cytokine challenge or respiratory viral infection. The results thereby provide the next advance in developing a small-molecule kinase inhibitor to address key features of respiratory disease. New and noteworthyThis study describes the discovery of a potent MAPK13-14 inhibitor and its effectiveness in models of respiratory airway disease. The findings thereby provide a scheme for pathogenesis and therapy of lung diseases (e.g., asthma, COPD, Covid-19, post-viral and allergic respiratory disease) and related conditions that implicate MAPK13-14 function. The findings also refine a hypothesis for epithelial and immune cell functions in respiratory disease that features MAPK13 as a possible component of this disease process.

immunology↗

bioRxiv2020

Chemokine receptor 2-targeted molecular imaging in pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive, inflammatory lung disease that is monitored clinically by measures of lung function, without effective molecular markers of disease activity or therapeutic efficacy. Lung immune cells active in the pro-fibrotic process include inflammatory monocyte and interstitial macrophages that express the C-C motif chemokine receptor 2 (CCR2). CCR2+ monocyte lung influx is essential for disease phenotypes in models of fibrosis and identified in lungs from subjects with IPF. Here, we show that our peptide-based radiotracer 64Cu-DOTA-ECL1i identifies CCR2+ inflammatory monocytes and interstitial macrophages in multiple preclinical mouse models of lung fibrosis, using positron emission tomography (PET) imaging. Mice with bleomycin-induced fibrosis treated with blocking antibodies to interleukin-1{beta}, a mediator of fibrosis associated with CCR2+ cell inflammation, or with pirfenidone, an approved anti-fibrotic agent, demonstrated decreased CCR2-dependent interstitial macrophage accumulation and reduced 64Cu-DOTA-ECL1i PET uptake, compared to controls. Lung tissues from patients with fibrotic lung disease demonstrated abundant CCR2+ cells surrounding regions of fibrosis, and an ex vivo tissue-binding assay showed correlation between radiotracer localization and CCR2+ cells. In a phase 0/1 clinical study of 64Cu-DOTA-ECL1i PET, healthy volunteers showed little lung uptake, while subjects with pulmonary fibrosis exhibited increased uptake, notably in zones of subpleural fibrosis, reflecting the distribution of CCR2+ cells in the profibrotic niche. These findings support a pathologic role of inflammatory lung monocytes/macrophages in fibrotic lung disease and the translational use of 64Cu-DOTA-ECL1i PET to track CCR2-specific inflammation for image-guided therapy. One Sentence SummaryPET imaging of CCR2+ cells in lung fibrosis identifies a therapeutic response in mouse models and displays a perifibrotic signal in subjects with IPF.

cell biology↗