The field of extracellular vesicles (EV) is rapidly expanding, also within cardiovascular diseases. Besides their exciting roles in cell-to-cell communication, EV have the potential to serve as excellent biomarkers, since their counts, content, and origin might provide useful information about the pathophysiology of cardiovascular disorders. Various studies have already indicated associations of EV counts and content with cardiovascular diseases. However, EV research is complicated by several factors, most notably the small size of EV. In this review, the advantages and drawbacks of EV-related methods and applications as biomarkers are highlighted.

The innate immune response is the first line of defense against viruses, and type I interferon (IFN) is a critical component of this response. Similar to other viruses, the gammacoronavirus infectious bronchitis virus (IBV) has evolved under evolutionary pressure to evade and counteract the IFN response to enable its survival. Previously, we reported that IBV induces a delayed activation of the IFN response. In the present work, we describe the resistance of IBV to IFN and the potential role of accessory proteins herein. We show that IBV is fairly resistant to the antiviral state induced by IFN and identify that viral accessory protein 3a is involved in resistance to IFN, as its absence renders IBV less resistant to IFN treatment. In addition to this, we found that independently of its accessory proteins, IBV inhibits IFN-mediated phosphorylation and translocation of STAT1. In summary, we show that IBV uses multiple strategies to counteract the IFN response. IMPORTANCEIn the present study, we show that infectious bronchitis virus (IBV) is resistant to IFN treatment and identify a role for accessory protein 3a in the resistance against the type I IFN response. We also demonstrate that, in a time-dependent manner, IBV effectively interferes with IFN signaling and that its accessory proteins are dispensable for this activity. This study demonstrates that the gammacoronavirus IBV, similar to its mammalian counterparts, has evolved multiple strategies to efficiently counteract the IFN response of its avian host, and it identifies accessory protein 3a as multifaceted antagonist of the avian IFN system. Infectious bronchitis virus (IBV) is a member of the genus Gammacoronavirus, a group of viruses from the order of Nidovirales characterized by a large positive-stranded RNA genome (1). IBV is the causative agent of infectious bronchitis, which is one of the most important viral diseases in chickens, a highly contagious respiratory disease that can spread to the gastrointestinal or the urogenital tract (2, 3). Despite widespread application of inactivated and live attenuated vaccines, infectious bronchitis remains one of the most reported diseases in poultry farms worldwide. Notwithstanding the widespread nature and economic importance of this virus, interactions between IBV and the host immune response remain poorly understood.During the immune response to viruses, the type I interferon (IFN) response plays a pivotal role. Recently, we have shown that IBV induces delayed activation of the interferon response (4) in a manner similar to that of several members of the genus Betacoronavirus, including mouse hepatitis virus (MHV), severe acute respiratory syndrome-associated coronavirus (SARS-CoV), and Middle East respiratory syndrome coronavirus (MERS-CoV) (5-8). The observation that coronaviruses delay activation of the IFN response and limit production of IFN suggests that IFN has the ability to hinder their propagation. In apparent contrast, most coronaviruses are relatively resistant to treatment with IFN in vit...

Platelets play an important role in the pathogenesis of vascular remodelling after injury. Junctional adhesion molecule A (JAM‐A) was recently described to regulate platelet activation. Specific deletion of JAM‐A from platelets resulted in increased reactivity and in accelerated progression of atherosclerosis. The aim of this study was to investigate the specific contribution of platelet‐derived JAM‐A to neointima formation after vascular injury. Mice with or without platelet‐specific (tr)JAM‐A‐deficiency in an apolipoprotein e (apoe−/−) background underwent wire‐induced injury of the common carotid artery. Ex vivo imaging by two‐photon microscopy revealed increased platelet coverage at the site of injury in trJAM‐A‐deficient mice. Cell recruitment assays showed increased adhesion of monocytic cells to activated JAM‐A‐deficient platelets than to control platelets. Inhibition of αMβ2 or GPIbα, but not of CD62P, suppressed those differences. Up to 4 weeks after wire injury, intimal neoplasia and neointimal cellular content were analysed. Neointimal lesion area was increased in trJAM‐A−/− apoe−/− mice and the lesions showed an increased macrophage accumulation and proliferating smooth muscle cells compared with trJAM‐A+/+ apoe−/− littermates 2 weeks, but not 4 weeks after injury. Re‐endothelialization was decreased in trJAM‐A−/− apoe−/− mice compared with controls 2 weeks after injury, yet it was complete in both groups after 4 weeks. A platelet gain of function by deletion of JAM‐A accelerates neointima formation only during earlier phases after vascular injury, through an increased recruitment of mononuclear cells. Thus, the contribution of platelets might become less important when neointima formation progresses to later stages.

Galectin-1 (gal-1) is a carbohydrate-binding lectin with important functions in angiogenesis, immune response, hemostasis and inflammation. Comparable functions are exerted by platelet factor 4 (CXCL4), a chemokine stored in the α-granules of platelets. Previously, gal-1 was found to activate platelets through integrin αIIbβ3. Both gal-1 and CXCL4 have high affinities for polysaccharides, and thus may mutually influence their functions. The aim of this study was to investigate a possible synergism of gal-1 and CXCL4 in platelet activation. Platelets were treated with increasing concentrations of gal-1, CXCL4 or both, and aggregation, integrin activation, P-selectin and phosphatidyl serine (PS) exposure were determined by light transmission aggregometry and by flow cytometry. To investigate the influence of cell surface sialic acid, platelets were treated with neuraminidase prior to stimulation. Gal-1 and CXCL4 were found to colocalize on the platelet surface. Stimulation with gal-1 led to integrin αIIbβ3 activation and to robust platelet aggregation, while CXCL4 weakly triggered aggregation and primarily induced P-selectin expression. Co-incubation of gal-1 and CXCL4 potentiated platelet aggregation compared with gal-1 alone. Whereas neither gal-1 and CXCL4 induced PS-exposure on platelets, prior removal of surface sialic acid strongly potentiated PS exposure. In addition, neuraminidase treatment increased the binding of gal-1 to platelets and lowered the activation threshold for gal-1. However, CXCL4 did not affect binding of gal-1 to platelets. Taken together, stimulation of platelets with gal-1 and CXCL4 led to distinct and complementary activation profiles, with additive rather than synergistic effects.

IntroductionIncreasingly more adolescent and young adult (AYA, aged 18–39 years) patients with an uncertain and/or poor cancer prognosis (UPCP) are gaining life-years because of novel treatments or refinement of established therapies, and sometimes even face the prospect of long-term disease control. This study aims to examine the challenges of AYAs with a UPCP in daily life to inform the development of AYA care programs.MethodsSemi-structured in-depth interviews were conducted among AYAs with a UPCP. Since we expected differences in experiences between three AYA subgroups, we interviewed patients of these subgroups (1): traditional survivors (2), low-grade glioma survivors, and (3) new survivors. Interviews were analyzed using elements of grounded theory. AYA patients were actively involved as research partners.ResultsIn total 46 AYAs with UPCP participated and shared their challenges in daily life. They were on average 33.4 years old (age range 23–44) and most of them were women (63%). The most common tumor types were low-grade gliomas (16), sarcomas (7), breast cancers (6), and lung cancers (6). We identified five primary themes: (1) feeling inferior to previous self and others (e.g. feeling useless, who wants me in a relationship), (2) feeling of being alone (e.g. lonely thoughts, nobody really gets me), (3) ongoing confrontation (e.g. it is always there, own decline), (4) grief about life (e.g. grief about life I did not get, grief about old life), and (5) loss of control over the future (e.g. not able to make future plans, waiting for growth). Although all of the challenges were identified in the three AYA subgroups, the perceived intensity of the challenges differed slightly between the subgroups.DiscussionAYAs living with a UPCP experience challenges associated to their sense of altered identity, their position in the social network, and the future uncertainties. This study highlights the importance to recognize and acknowledge the unique challenges of this group. To provide age-specific care, it is important to embed acceptance and commitment therapy and AYA peer support within the healthcare system and other care programs to support AYAs to live well with their disease.