The endothelial glycocalyx (EGC) is a layer of proteoglycans (associated with glycosaminoglycans) and glycoproteins, which adsorbs plasma proteins on the luminal surface of endothelial cells. Its ...main function is to participate in separating the circulating blood from the inner layers of the vessels and the surrounding tissues. Physiologically, the EGC stimulates mechanotransduction, the endothelial charge, thrombocyte adhesion, leukocyte tissue recruitment, and molecule extravasation. Hence, severe impairment of the EGC has been implicated in various pathological conditions, including sepsis, diabetes, chronic kidney disease, inflammatory disorders, hypernatremia, hypervolemia, atherosclerosis, and ischemia/reperfusion injury. Moreover, alterations in EGC have been associated with altered responses to therapeutic interventions in conditions such as cardiovascular diseases. Investigation into the function of the glycocalyx has expanded knowledge about vascular disorders and indicated the need to consider new approaches in the treatment of severe endothelial dysfunction. This review aims to present the current understanding of the molecular mechanisms underlying cardiovascular diseases and to elucidate the impact of heart surgery on EGC dysfunction.
Cardiac surgery is one of the highest-risk procedures, usually involving cardiopulmonary bypass and commonly inducing endothelial injury that contributes to the development of perioperative and ...postoperative organ dysfunction. Substantial scientific efforts are being made to unravel the complex interaction of biomolecules involved in endothelial dysfunction to find new therapeutic targets and biomarkers and to develop therapeutic strategies to protect and restore the endothelium. This review highlights the current state-of-the-art knowledge on the structure and function of the endothelial glycocalyx and mechanisms of endothelial glycocalyx shedding in cardiac surgery. Particular emphasis is placed on potential strategies to protect and restore the endothelial glycocalyx in cardiac surgery. In addition, we have summarized and elaborated the latest evidence on conventional and potential biomarkers of endothelial dysfunction to provide a comprehensive synthesis of crucial mechanisms of endothelial dysfunction in patients undergoing cardiac surgery, and to highlight their clinical implications.
Dendritic cells (DC)/natural killer (NK) cells interactions in the deciduas of early human pregnancies were analyzed in vitro.
Phenotype, cytokine expression and/or cytolytic mediators' expression ...were measured by flow cytometry in NK and DC from the freshly isolated decidual mononuclear cells or after their purification and co-culture in vitro. Proliferation of 5(6)-Carboxyfluorescein diacetate N-succinimidyl ester (CFSE)-labeled CD56(+) cells was analyzed by flow cytometry after the co-culture with CD1a(+) or CD83(+) DC.
Decidual CD1a(+) cells show less mature phenotype with no expression of CD197, lower expression of CD80 and CD86 and higher expression of CD206 and CD195 in comparison to CD83(+) cells. Interleukin (IL)-15, interferon-gamma and tumor necrosis factor-alpha productions were higher in immature than mature DC, whereas IL-10 and IL-18 were equally produced in both subpopulations. Immature DC increase perforin, FasL and TRAIL protein expression and proliferation of NK cells, but decrease their intracellular IL-15 production. Mature DC caused less efficient proliferation of NK cells, and did not affect cytokine and cytolytic mediator expression.
These results suggest that decidual CD1a(+) cells regulate and shape NK cell function more profoundly than CD83(+) cells in decidua.
Summary Background Perforin is a membrane-disrupting protein that allows the entry of granzymes into a target cell inducing degradation of target substances in the cytoplasm and nucleus thus leading ...to programmed cell death or apoptosis. Recent work demonstrated a possible involvement of perforin mediated cytotoxicity in immunopathogenesis of psoriasis. Objectives To investigate a difference in systemic (peripheral blood) and local (lesions) expression and distribution of perforin in psoriatic patients with severe and mild disease. Methods Flow cytometry was used for simultaneous detection of intracellular (perforin) and cell surface antigens in peripheral blood lymphocytes. The expression of perforin in skin lesions was evaluated by immunohistochemistry. Results Significant increase of perforin expression in T lymphocytes, especially cytotoxic CD8+ cells was found in severe psoriasis compared to mild disease ( p < 0.01 and p < 0.05, respectively). There was also an increase of CD56+P+ NK cells ( p < 0.05) in severe compared to mild psoriasis. The psoriatic plaque of both, severe and mild disease were abundant with perforin showing no significant difference on local level. Conclusion Based on our results we suggest the association between perforin expression and disease severity.
Heat shock proteins (hsps), in certain circumstances, could shape unique features of decidual dendritic cells (DCs) that play a key role in inducing immunity as well as maintaining tolerance. The aim ...of the study was to assess the binding of gp96 to Toll-like receptor (TLR) 4 and CD91 receptors on decidual CD1a
DCs present at the maternal-fetal interface in vitro as well as the influence of CD1a
DCs maturation status. Immunohistology and immunofluorescence of paraffin-embedded first-trimester decidua tissue sections of normal and pathological (missed abortion MA and blighted ovum BO) pregnancies were performed together with flow cytometry detection of antigens in CD1a
DCs after gp96 stimulation of decidual mononuclear cells. Gp96 efficiently bound CD91 and TLR4 receptors on decidual CD1a
DCs in a dose-dependent manner and increased the expression of CD83 and HLA-DR. The highest concentration of gp96 (1000 ng/mL) increased the percentage of Interferon-γ (INF-γ) and IL-15 expressing gp96
cells. Gp96 binds CD91 and TLR4 on decidual CD1a
DCs, which causes their maturation and significantly increases INF-γ and IL-15 in the context of Th1 cytokine/chemokine domination, which could support immune response harmful for ongoing pregnancy.
We investigated the polarisation of CD68+ macrophages and perforin and granulysin distributions in kidney lymphocyte subsets of children with IgA vasculitis nephritis (IgAVN). Pro-inflammatory ...macrophage (M)1 (CD68/iNOS) or regulatory M2 (CD68/arginase-1) polarisation; spatial arrangement of macrophages and lymphocytes; and perforin and granulysin distribution in CD3+ and CD56+ cells were visulaised using double-labelled immunofluorescence. In contrast to the tubules, iNOS+ cells were more abundant than the arginase-1+ cells in the glomeruli. CD68+ macrophage numbers fluctuated in the glomeruli and were mostly labelled with iNOS. CD68+/arginase-1+ cells are abundant in the tubules. CD56+ cells, enclosed by CD68+ cells, were more abundant in the glomeruli than in the tubuli, and co-expressed NKp44. The glomerular and interstitial/intratubular CD56+ cells express perforin and granulysin, respectively. The CD3+ cells did not express perforin, while a minority expressed granulysin. Innate immunity, represented by M1 macrophages and CD56+ cells rich in perforin and granulysin, plays a pivotal role in the acute phase of IgAVN.
Background:
We analysed clinical and biochemical parameters in predicting severe gastrointestinal (GI) manifestations in childhood IgA vasculitis (IgAV) and the risk of developing renal ...complications.
Methods:
A national multicentric retrospective study included children with IgAV reviewed in five Croatian University Centres for paediatric rheumatology in the period 2009–2019.
Results:
Out of 611 children, 281 (45.99%) had at least one GI manifestation, while 42 of 281 (14.95%) had the most severe GI manifestations. Using logistic regression several clinical risk factors for the severe GI manifestations were identified: generalized rash odds ratio (OR) 2.09 (95% confidence interval (CI) 1.09–4.01), rash extended on upper extremities (OR 2.77 (95% CI 1.43–5.34) or face OR 3.69 (95% CI 1.42–9.43) and nephritis (IgAVN) OR 4.35 (95% CI 2.23–8.50), as well as lower values of prothrombin time (OR 0.05 (95% CI 0.01–0.62), fibrinogen OR 0.45 (95% CI 0.29–0.70) and IgM OR 0.10 (95% I 0.03–0.35) among the laboratory parameters. Patients with severe GI involvement more frequently had relapse of the disease OR 2.14 (CI 1.04–4.39) and recurrent rash OR 2.61 (CI 1.27–5.38). Multivariate logistic regression found that the combination of age, GI symptoms at the beginning of IgAV and severity of GI symptoms were statistically significant predictors of IgAVN. Patients in whom IgAV has started with GI symptoms OR 6.60 (95% CI 1.67–26.06), older children OR 1.22 (95% CI 1.02–1.46) with severe GI form of IgAV (OR 5.90 (95% CI 1.12–31.15) were particularly high-risk for developing IgAVN.
Conclusion:
We detected a group of older children with the onset of GI symptoms before other IgAV symptoms and severe GI form of the IgAV, with significantly higher risk for acute and chronic complications of IgAV.
Immature monocyte-derived dendritic cells (DC) strongly express the endocytic mannose receptor (MR). Addition of a specific anti-MR mAb (clone PAM-1) for 24 h to cultures of immature DC induced ...phenotypical and functional maturation of the cells, assessed as up-regulation of costimulatory molecules and CD83, and chemotactic response to CCL19. A different isotype-matched anti-MR mAb (clone 19.2) had no significant effect. Engagement of MR with mAb PAM-1 induced the production of the anti-inflammatory cytokines IL-10, IL-1R antagonist, and of the nonsignaling IL-1R type II. In contrast IL-1beta, TNF, and IL-12 were not produced. PAM-1-treated DC were unable to polarize Th1 effector cells and did not secrete the chemokines CXCL10 and CCL19; in turn, they produced large amounts of CCL22 and CCL17, thus favoring the amplification of Th2 circuits. T cells cocultured with PAM-1-matured DC initially proliferated but later became anergic and behaved as suppressor/regulatory cells. Natural ligands binding to MR had differential effects. MUC III (a partially purified mucin), biglycan (a purified complex proteoglycan), and mannosylated lipoarabinomannan from Mycobacterium tuberculosis affected cytokine production with high IL-10, IL-1R antagonist, IL-1R type II, and inhibition of IL-12. In contrast, mannan, dextran, and thyroglobulin had no significant effect. In conclusion, the appropriate engagement of the MR by mAb PAM-1 and selected natural ligands elicit a secretory program in mono-derived DC characterized by a distinct profile of cytokines/chemokines with the ability to dampen inflammation and to inhibit the generation of Th1-polarized immune responses.
Abstract When medication management or percutaneous coronary intervention is not successful in patients with advanced ischemic heart disease, surgical revascularisation—predominantly coronary artery ...bypass grafting (CABG)—is considered the gold standard. However, CABG surgery can lead to ischemia/reperfusion injury, which is characterized by a strong inflammatory response. Interleukin (IL)-18, is a strong inflammatory mediator, that is released from cardiomyocytes and can be found in the systemic circulation of patients during and immediately after CABG surgery. The existing damage of endothelial glycocalyx in patients with ischemic heart disease is further impaired concurrently during the surgery due to the anaesthesia-surgical technique used and intravascular fluid loading. This results in the increased incidence of adverse events, including myocardial infarction. IL-18 leads to the activation of lymphocyte cytotoxicity via cytotoxic mediators (Fas ligand, Tumour necrosis factor (TNF)-related apoptosis-inducing ligand, perforin, and granulysin). We hypothesize that IL-18 is released locally in the heart and the systemic circulation in patients undergoing CABG surgery and may be correlated with the level of activity of circulating lymphocytes. In turn, this may lead to lymphocyte-mediated cytotoxicity directed toward damaged and activated endothelial cells. Shear stress glycocalyx, as well as damaged and activated endothelial cells then become the main the source of pro-inflammatory cytokines, chemokines, and adhesion molecules. These attract activated lymphocytes to adhere to the endothelium or enter the subintimal layer, increasing existing or initiating the formation of new plaques, which leads to the development of myocardial infarction during or shortly after surgery. To evaluate our hypothesis, we will measure the local concentration of IL-18 in the sinus coronarius and systemic circulation. These values will then be correlated with immunological and biochemical parameters, predominantly with the concentration of degradation products of glycocalyx and cytotoxic mediators in activated lymphocytes. If our hypothesis is correct, measuring the IL-18 concentration that is responsible for glycocalyx deterioration, may become a useful tool for predicting myocardial infarction occurrence in patients undergoing CABG surgery.
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