RNA-binding proteins (RBPs) are multi-faceted proteins in the regulation of RNA or its RNA splicing, localisation, stability, and translation. Amassing proof from many recent and dedicated studies reinforces the perception of RBPs exerting control through differing expression levels, cellular localization and post-transcriptional alterations. However, since the regulation of RBPs is reliant on the micro-environment and events like stress response and metabolism, their binding affinities and the resulting RNA-RBP networks may be affected. Therefore, any misregulation and disruption in the features of RNA and its related homeostasis can lead to a number of diseases that include diabetes, cardiovascular disease, and other disorders such as cancer and neurodegenerative diseases. As such, correct regulation of RNA and RBPs is crucial to good health as the effect RBPs exert through loss of function can cause pathogenesis. In this review, we will discuss the significance of RBPs and their typical function and how this can be disrupted in disease.

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Chronic damage and repair of the bronchial epithelium are features of asthma. We have previously reported that ex vivo stimulation of normal bronchial epithelial cells with epidermal growth factor (EGF), a key factor of epithelial repair, enhances the mechanisms of neutrophil accumulation, thereby promoting neutrophil defences during acute injury but potentially enhancing inflammation in chronic airway diseases. We have now sought to (i) determine whether this EGF-dependent pro-neutrophil activity is increased in asthma, where EGF and its epithelial receptor are over-expressed, and (ii) elucidate some of the mechanisms underlying this asthmatic epithelial-neutrophil interaction. Primary bronchial epithelial cells (PBEC) from healthy subjects, mild asthmatics and moderate-to-severe asthmatics (Mod/Sev) were stimulated with EGF, a model that mimics a repairing epithelium. Conditioned culture media (EGF-CM) were assessed for neutrophil chemotactic and anti-apoptotic activities and inflammatory mediator production. EGF induced the epithelium to produce soluble mediators with neutrophil chemotactic (p<0.001) and pro-survival (p = 0.021) activities which were related to the clinical severity of asthma (trend p = 0.010 and p = 0.009, respectively). This was associated with enhanced IL-6, IL-8, GM-CSF and TNF-α release, and cytokine-neutralising experiments using EGF-CM from Mod/Sev asthmatics demonstrated a role for GM-CSF in neutrophil survival (p<0.001). Pre-treatment of neutrophils with specific inhibitors of the myeloid-restricted class I phosphatidylinositol-3-OH kinase (PI(3)K) isoforms showed that the EGF-CM from Mod/Sev asthmatics depended on the γ (p<0.021) but not δ isoforms, while neutrophil survival required multiple class I PI(3)Ks. The EGF-induced chemotactic, but not pro-survival activity, involved RhoA signaling in neutrophils (p = 0.012). EGF whose activity is upregulated in asthma induces ex vivo the epithelium from asthmatic patients to produce pro-neutrophil activities; these are related to asthma severity and, in moderate-to-severe asthmatics, involves class IB PI(3)Kγ signaling, providing a potential therapeutic target for neutrophilic forms of asthma.

Cardiovascular disease (CVD) is a general term for conditions which are the leading cause of death in the world. Quick restoration of tissue perfusion is a key factor to combat these diseases and improve the quality and duration of patients' life. Revascularization techniques include angioplasty, placement of a stent, or surgical bypass grafting. For the latter technique, autologous vessels remain the best clinical option; however, many patients lack suitable autogenous due to previous operations and they are often unsuitable. Therefore, synthetic vascular grafts providing antithrombosis, neointimal hyperplasia inhibition and fast endothelialization are still needed. To address these limitations, 3D printed dipyridamole (DIP) loaded biodegradable vascular grafts were developed. Polycaprolactone (PCL) and DIP were successfully mixed without solvents and then vascular grafts were 3D printed. A mixture of high and low molecular weight PCL was used to better ensure the integration of DIP, which would offer the biological functions required above. Moreover, 3D printing technology provides the ability to fabricate structures of precise geometries from a 3D model, enabling to customize the vascular grafts' shape or size. The produced vascular grafts were fully characterized through multiple techniques and the last step was to evaluate their drug release, antiplatelet effect and cytocompatibility. The results suggested that DIP was properly mixed and integrated within the PCL matrix. Moreover, these materials can provide a sustained and linear drug release without any obvious burst release, or any faster initial release rates for 30 days. Compared to PCL alone, a clear reduced platelet deposition in all the DIP-loaded vascular grafts was evidenced. The hemolysis percentage of both materials PCL alone and PCL containing 20% DIP were lower than 4%. Moreover, PCL and 20% DIP loaded grafts were able to provide a supportive environment for cellular attachment, viability, and growth.