The MUC5B promoter variant results in proteomic changes in the nonfibrotic lung.

The gain-of-function MUC5B promoter variant is the dominant risk factor for the development of idiopathic pulmonary fibrosis (IPF). However, its impact on protein expression in both nonfibrotic control and IPF lung specimens has not been well characterized. Utilizing laser capture microdissection coupled to mass spectrometry, we investigated the proteomic profiles of airway and alveolar epithelium in nonfibrotic controls (n = 12) and IPF specimens (n = 12), stratified by the MUC5B promoter variant.

Proteomic profiling of human plasma and intervertebral disc tissue reveals matrisomal, but not plasma, biomarkers of disc degeneration.

Background: Intervertebral disc (IVD) degeneration is a common cause of low back pain, and the most symptomatic patients with neural compression need surgical intervention to relieve symptoms. Current techniques used to diagnose IVD degeneration, such as magnetic resonance imaging (MRI), do not detect changes in the tissue extracellular matrix (ECM) as degeneration progresses. Improved techniques, such as a combination of tissue and blood biomarkers, are needed to monitor the progression of IVD degeneration for more effective treatment plans.

Endocytic recycling is central to circadian collagen fibrillogenesis and disrupted in fibrosis.

Collagen-I fibrillogenesis is crucial to health and development, where dysregulation is a hallmark of fibroproliferative diseases. Here, we show that collagen-I fibril assembly required a functional endocytic system that recycles collagen-I to assemble new fibrils. Endogenous collagen production was not required for fibrillogenesis if exogenous collagen was available, but the circadian-regulated vacuolar protein sorting (VPS) 33b and collagen-binding integrin α11 subunit were crucial to fibrillogenesis.

Modeling collagen fibril self-assembly from extracellular medium in embryonic tendon.

Collagen is a key structural component of multicellular organisms and is arranged in a highly organized manner. In structural tissues such as tendons, collagen forms bundles of parallel fibers between cells, which appear within a 24-h window between embryonic day 13.5 (E13.

Morphologically intact airways in lung fibrosis have an abnormal proteome.

Honeycombing is a histological pattern consistent with Usual Interstitial Pneumonia (UIP). Honeycombing refers to cystic airways located at sites of dense fibrosis with marked mucus accumulation. Utilizing laser capture microdissection coupled mass spectrometry (LCM-MS), we interrogated the fibrotic honeycomb airway cells and fibrotic uninvolved airway cells (distant from honeycomb airways and morphologically intact) in specimens from 10 patients with UIP.

The UIP/IPF fibroblastic focus is a collagen biosynthesis factory embedded in a distinct extracellular matrix.

Usual interstitial pneumonia (UIP) is a histological pattern characteristic of idiopathic pulmonary fibrosis (IPF). The UIP pattern is patchy with histologically normal lung adjacent to dense fibrotic tissue. At this interface, fibroblastic foci (FF) are present and are sites where myofibroblasts and extracellular matrix (ECM) accumulate.

MicroRNAs in Mechanical Homeostasis.

Mechanical variables such as stiffness, stress, strain, and fluid shear stress are central to tissue functions, thus, must be maintained within the proper range. Mechanics are especially important in the cardiovascular system and lung, the functions of which are essentially mechanical. Mechanical homeostasis is characterized by negative feedback in which deviations from the optimal value or set point activates mechanisms to return the system to the correct range.

IL-13 deficiency exacerbates lung damage and impairs epithelial-derived type 2 molecules during nematode infection.

IL-13 is implicated in effective repair after acute lung injury and the pathogenesis of chronic diseases such as allergic asthma. Both these processes involve matrix remodelling, but understanding the specific contribution of IL-13 has been challenging because IL-13 shares receptors and signalling pathways with IL-4. Here, we used infection as a model of acute lung damage comparing responses between WT and IL-13-deficient mice, in which IL-4 signalling is intact.

Laser capture microdissection coupled mass spectrometry (LCM-MS) for spatially resolved analysis of formalin-fixed and stained human lung tissues.

Background: Haematoxylin and eosin (H&E)-which respectively stain nuclei blue and other cellular and stromal material pink-are routinely used for clinical diagnosis based on the identification of morphological features. A richer characterization can be achieved by laser capture microdissection coupled to mass spectrometry (LCM-MS), giving an unbiased assay of the proteins that make up the tissue. However, the process of fixing and H&E staining of tissues provides challenges with standard sample preparation methods for mass spectrometry, resulting in low protein yield.