The role of costimulatory receptors of the tumour necrosis factor receptor family in atherosclerosis

Pharmacologic HIF stabilization activates costimulatory receptor expression to increase antitumor efficacy of adoptive T cell therapy

Adoptive cell transfer (ACT) is a therapeutic strategy to augment antitumor immunity. Here, we report that ex vivo treatment of mouse CD8+ T cells with dimethyloxalylglycine (DMOG), a stabilizer of hypoxia-inducible factors (HIFs), induced HIF binding to the genes encoding the costimulatory receptors CD81, GITR, OX40, and 4-1BB, leading to increased expression. DMOG treatment increased T cell killing of melanoma cells, which was further augmented by agonist antibodies targeting each costimulatory receptor. In tumor-bearing mice, ACT using T cells treated ex vivo with DMOG and agonist antibodies resulted in decreased tumor growth compared to ACT using control T cells and increased intratumoral markers of CD8+ T cells (CD7, CD8A, and CD8B1), natural killer cells (NCR1 and KLRK1), and cytolytic activity (perforin-1 and tumor necrosis factor-α). Costimulatory receptor gene expression was also induced when CD8+ T cells were treated with three highly selective HIF stabilizers that are currently in clinical use.

CD28null T cells in aging and diseases: From biology to assessment and intervention

CD28null T cells, an atypical subset characterized by the loss of CD28 costimulatory molecule expression, exhibit functional variants and progressively expand with age. Moreover, T cells with these phenotypes are found in both typical and atypical humoral immune responses. Consequently, they accumulate during infectious diseases, autoimmune disorders, cardiovascular conditions, and neurodegenerative ailments. To provide an in-depth review of the current knowledge regarding CD28null T cells, we specifically focus on their phenotypic and functional characteristics as well as their physiological roles in aging and diseases. While uncertainties regarding the clinical utility remains, we will review the following two crucial research perspectives to explore clinical translational applications of the research on this specific T cell subset: 1) addressing the potential utility of CD28null T cells as immunological markers for prognosis and adverse outcomes in both aging and disease, and 2) speculating on the potential of targeting CD28null T cells as an interventional strategy for preventing or delaying immune aging processes and disease progression.

Suppression of microRNA-155 exerts an anti-inflammatory effect on CD4+ T cell-mediated inflammatory response in the pathogenesis of atherosclerosis

In the current study, we aimed to investigate the effects of miR-155 on CD4+ T cell-mediated immune response in the pathogenesis of atherosclerosis. CD34+ hematopoietic stem cells, CD4+ T lymphocytes, endothelial cells (ECs), and vascular smooth muscle cells (VSMCs) were harvested from the same donor. Knockdown of miR-155 in the CD4+ T cells was achieved by lentiviral transfection, whereas control RNA-transfected or untransfected lymphocytes were used as controls. The transfected CD4+ T cells were activated by incubating with oxidized low-density lipoprotein-treated dendritic cells. The proliferative capacities, phenotype distribution, and cytokine secretion profiles of the activated CD4+ T cells from different groups were evaluated. The activated lymphocytes were used to treat ECs co-cultivated with VSMCs. The ability of the CD4+ T cells to induce the apoptosis of the ECs and to promote the proliferation of the VSMCs was investigated. Inhibition of miR-155 was found to significantly reduce the proliferation rate of the transfected CD4+ T cells. CD4+ T lymphocytes transfected with the miR-155 inhibitor showed increased populations of T helper type 2 and regulatory T cells, as well as more production of anti-inflammatory cytokines. MiR-155 knockdown was also shown to significantly hamper the ability to CD4+ T cells to induce EC apoptosis and to promote the growth of VSMCs. Our data suggested that inhibition of miR-155 in CD4+ T cells could slow down the formation of atherosclerotic plaques. These results lay the groundwork for future research on the therapeutic potential of miR-155 against atherosclerosis-associated cardiovascular diseases.

Values of serum LDL and PCT levels in evaluating the condition and prognosis of acute cerebral infarction

Values of low density lipoprotein (LDL) and procalcitonin (PCT) levels in evaluating the condition and prognosis of patients with acute cerebral infarction (ACI) were investigated. According to the volume of cerebral infarction, 150 patients with ACI (observation group) were divided into the mild infarction group (n=50), moderate infarction group (n=50), and severe infarction group (n=50). Besides, another 50 healthy subjects were enrolled during the same period as the control group. The levels of serum LDL and PCT on admission and at the 1st, 3rd, 7th and 10th day after treatment were detected, which were compared with those in the control group. Ten days after treatment, patients were divided into two groups, the effective group and non-effective group, based on the clinical efficacy. The differences in LDL and PCT levels were compared between the two groups. After 1 month, the clinical efficacy was evaluated again, and the correlations of LDL and PCT levels with prognosis were analyzed. The levels of serum LDL and PCT in the observation group 1 day after admission were higher than those in the control group (P<0.05), which reached the peak at the 3rd day and continuously declined after the 7th day. The LDL and PCT levels had statistically significant differences between the effective group and non-effective group (P<0.05). Pearson's correlation analysis showed that the serum LDL and PCT levels in acute phase were negatively correlated with the National Institutes of Health Stroke Scale (NIHSS) score after 1 month of treatment (P<0.05). The dynamic monitoring of serum LDL and PCT levels in ACI patients can help evaluate the condition and prognosis of patients.

Beat-to-Beat Blood Pressure and Two-dimensional (axial and radial) Motion of the Carotid Artery Wall: Physiological Evaluation of Arterial Stiffness

The physiological relationship between local arterial displacement and blood pressure (BP) plays an integral role in assess- ment of the mechanical properties of arteries. In this study, we used more advanced methods to obtain reliable continuous BP and the displacement of the common carotid artery (CCA) simultaneously. We propose a novel evaluation method for arterial stiffness that relies on determining the physiological relationship between the axial and radial displacements of the CCA wall and beat-to-beat BP. Patients (total of 138) were divided into groups according to the following three criteria: essential hyper- tension (EH) and normotension, male and female, elderly and younger. The Pearson correlation test and canonical correlation analysis showed that the CCA indices were significantly correlated with BP indices (r = 0:787; p < 0:05). The slope of the CCA displacement/pressure curve showed a progressive reduction with increasing age and EH disease occurrence (EH: 0.496 vs. normotension: 0.822; age <= 60:0.585 vs. age > 60:0.783). Our method provides an explicit reference value and relationship for the manner in which the CCA wall responds to changes in BP. Short-term and continuous BP were significantly correlated with CCA displacement and exhibited a close inverse relationship with each subject's BP and EH, age, and systolic blood pressure.

Targeting T cells to treat atherosclerosis: odyssey from bench to bedside

More than 150 years from the initial description of inflammation in atherosclerotic plaques, randomized clinical trials to test anti-inflammatory therapies in atherosclerosis have recently been initiated. Lymphocytes and macrophages are main participants in the inflammatory response in atherosclerosis. T lymphocytes operate mainly by exerting strong influences on the function of many cells in the immune system and beyond, and co-ordinating their interactions. Importantly, T lymphocytes are not a homogenous population, but include several subsets with specialized functions that can either promote or suppress inflammation. The interactions between these T-lymphocyte subsets have critical consequences on the course and outcome of inflammation. The complexity of the inflammatory response in atherosclerosis poses significant challenges on translating experimental findings into clinical therapies and makes the journey from bench to bedside an arduous one. Here, we summarize recent advances on the role of CD4⁺ T cells in the inflammatory process in atherosclerosis and discuss potential therapies to modulate these lymphocytes that may provide future breakthroughs in the treatment of atherosclerosis.

Lack of Association Between rs17568 Polymorphism in OX40 Gene and Myocardial Infarction, Southern of Iran

Tumor necrosis factor (TNF) is one of the inflammatory cytokines which has an important role in inflammation and migration of other inflammatory cells to the atherosclerotic plaques. OX40 is a member of the TNF super family receptor protein. OX40 and OX40 ligand are co-stimulators for T-cells and can increase inflammatory response in atherosclerotic plaques. The aim of this study was to determine the association of rs17568 polymorphism in OX40 gene with premature myocardial infarction. This case control study was done on 100 patients with premature acute myocardial infarction (AMI) and a similar number of sex, age and some other cardiovascular risk factor matched healthy people. The OX40 rs17568 polymorphism was genotyped, using PCR-RFLP method. A-allele frequency of rs17568 SNP was lower non-significantly in Premature AMI, compared to healthy subjects (49% vs. 51%). The analysis of rs17568 (A/G) polymorphism showed an odds ratio of 1.127 (95% CI: 0.635-1.999; P= 0.686) for the GG genotype and 5.761 (95% CI: 1.200-27.655; P= 0.029) for the AG genotype, compared to the AA genotype. The results of this study indicate that the rs17568 SNP of OX40 gene is not associated with premature AMI in the evaluated population.

The life (and death) of CD4+ CD28(null) T cells in inflammatory diseases

Inflammation contributes to the development and perpetuation of several disorders and T lymphocytes orchestrate the inflammatory immune response. Although the role of T cells in inflammation is widely recognized, specific therapies that tackle inflammatory networks in disease are yet to be developed. CD4(+) CD28(null) T cells are a unique subset of helper T lymphocytes that recently shot back into the limelight as potential catalysts of inflammation in several inflammatory disorders such as autoimmunity, atherosclerosis and chronic viral infections. In contrast to conventional helper T cells, CD4(+) CD28(null) T cells have an inbuilt ability to release inflammatory cytokines and cytotoxic molecules that can damage tissues and amplify inflammatory pathways. It comes as no surprise that patients who have high numbers of these cells have more severe disease and poor prognosis. In this review, I provide an overview on the latest advances in the biology of CD4(+) CD28(null) T cells. Understanding the complex functions and dynamics of CD4(+) CD28(null) T cells may open new avenues for therapeutic intervention to prevent progression of inflammatory diseases.

The mutual interplay of lipid metabolism and the cells of the immune system in relation to atherosclerosis

Atherosclerosis is a chronic inflammation in the arterial wall involving cells of the innate and adaptive immune system that is promoted by hyperlipidemia. In addition, the immune system can influence lipids and lipoprotein levels and cellular lipid homeostasis can influence the level and function of the immune cells. We will review the effects of manipulation of adaptive immune cells and immune cell products on lipids and lipoproteins, focusing mainly on studies performed in murine models of atherosclerosis. We also review how lipoproteins and cellular lipid levels, particularly cholesterol levels, influence the function of cells of the innate and adaptive immune systems. The overriding theme is that these interactions are driven by the need to provide the energy and membrane components for cell proliferation and migration, membrane expansion and other functions that are so important in the functioning of the immune cells.

Costimulatory pathways in kidney transplantation: pathogenetic role, clinical significance and new therapeutic opportunities

Costimulatory pathways play a key role in immunity, providing the second signal required for a full activation of adaptive immune response. Different costimulatory families (CD28, TNF-related, adhesion and TIM molecules), characterized by structural and functional analogies, have been described. Costimulatory molecules modulate T cell activation, B cell function, Ig production, cytokine release and many other processes, including atherosclerosis. Patients suffering from renal diseases present significant alterations of the costimulatory pathways, which might make them particularly liable to infections. These alterations are further pronounced in patients undergoing kidney transplantation. In these patients, different costimulatory patterns have been related to distinct clinical features. The importance that costimulation has gained during the last years has led to development of several pharmacological approaches to modulate this critical step in the immune activation. Different drugs, mainly monoclonal antibodies targeting various costimulatory molecules (i.e. anti-CD80, CTLA-4 fusion proteins, anti-CD154, anti-CD40, etc.) were designed and tested in both experimental and clinical studies. The results of these studies highlighted some criticisms, but also some promising findings and now costimulatory blockade is considered a suitable strategy, with belatacept (a CTLA-4 fusion protein) being approved as the first costimulatory blocker for use in renal transplantation. In this review, we summarize the current knowledge on costimulatory pathways in the setting of kidney transplantation. We describe the principal costimulatory molecule families, their role and clinical significance in patients undergoing renal transplantation and the new therapeutic approaches that have been developed to modulate the costimulatory pathways.

Lymphocytic tumor necrosis factor receptor superfamily co-stimulatory molecules in the pathogenesis of atherosclerosis

PURPOSE OF REVIEW

The role of lymphocytes in the chronic inflammatory disease atherosclerosis has emerged over the past decade. Co-stimulatory molecules of the heterogeneous tumor necrosis factor receptor superfamily play a pivotal role in lymphocyte activation, proliferation and differentiation. Here we describe the immune modulatory properties and mechanisms of four tumor necrosis factor receptor superfamily members in atherosclerosis.

RECENT FINDINGS

CD40/CD40L, OX40L/OX40, CD70/CD27 and CD137/CD137L are present in human atherosclerotic plaques and have shown strong immune modulatory functions in atherosclerosis, resulting in either atherogenic or atheroprotective effects in mouse models of atherosclerosis.

SUMMARY

Insight into the immune modulatory mechanisms of co-stimulatory interactions in atherosclerosis can contribute to clinical exploitation of these interactions in the treatment of cardiovascular disease.