T cell co-stimulation and co-inhibition in cardiovascular disease: a double-edged sword

Gut microbiota-derived imidazole propionate: an emerging target for the prevention and treatment of cardiometabolic diseases

Despite significant advancements in prevention and treatment, cardiometabolic diseases continue to pose a high burden of incidence and mortality. The chronic progression of these diseases necessitates the identification of early and complementary therapeutic targets to elucidate and mitigate residual risks in patient care. The gut microbiota acts as a sentinel between internal and external environments, transmitting modified risks associated with these factors to the host. Imidazole propionate (ImP), a histidine metabolite originating from the gut microbiota, gained attention after being found to impair glucose tolerance and insulin signaling several years ago. Epidemiological studies over the past five years have demonstrated a robust correlation between ImP and an increased risk of onset of type 2 diabetes (T2D) and obesity, exacerbation of kidney traits in chronic kidney disease (CKD), progression of atherosclerotic plaques, and elevated mortality rates in heart failure (HF). These findings suggest that ImP may serve as a pivotal target for the prevention and treatment of cardiometabolic diseases. Mechanistic insights have uncovered associations between ImP and insulin resistance, impaired glucose metabolism, chronic inflammation, and intestinal barrier damage. This review provides a comprehensive summary of the current evidence regarding the association between ImP and cardiometabolic impairment, highlighting its potential in advancing personalized approaches to disease prevention and management, and exploring the intricate interplay of diet, gut microbiota, and ImP in cardiovascular metabolic impairment. Overall, this review offers valuable insights into the multifaceted roles of ImP in cardiometabolic diseases, identifies current knowledge gaps, and discusses future research directions.

Moxibustion Regulates the Expression of T Cells in Rheumatoid Arthritis Through Tim-3/Gal-9 Signaling Pathway

To observe the effects of moxibustion on T cells and T cell immunoglobulin and mucin-domain-containing molecule-3/galectin-9 (Tim-3/Gal-9) pathway in rats with rheumatoid arthritis (RA). To further explore the possible anti-inflammatory mechanism of moxibustion in the treatment of RA. Thirty Sprague Dawley rats were randomly divided into three groups, including a control group, an RA model group, and a moxibustion group. An RA model was created through the injection of Freund's complete adjuvant. In the moxibustion group, rats were treated with moxibustion at acupoints of "Shenshu" and "Zusanli." A total of three courses of treatment were conducted. Then the thickness of foot pad was measured, joint pathological changes were observed by hematoxylin-eosin (HE) staining, the proportion of CD4+T and CD8+T in peripheral blood was detected by flow cytometry, the expression levels of Tim-3 and Gal-9 in synovium were detected by polymerase chain reaction (PCR), and the expressions of CD4+T and CD8+T in synovium were detected by immunofluorescence. HE staining showed that the synovial tissue of the control group was smooth and neatly arranged without inflammatory cell infiltration. In the model group, the joint space was narrowed, the synovial tissue had congestion and edema, and a large number of inflammatory cells infiltrated. Compared with the model group, in the moxibustion group, the joint space narrowed with synovium hyperemia and edema, and the level of inflammatory cell infiltration decreased. Flow cytometry showed that compared with the model group, CD4+T expression in the moxibustion group was downregulated, while CD8+T expression was upregulated. PCR results showed that compared with the model group, the expressions of Tim-3 and Gal-9 in the moxibustion group were upregulated. Immunofluorescence results showed that compared with the model group, CD4+T expression in the moxibustion group was decreased, while CD8+T expression was increased. The results demonstrate that moxibustion not only suppressed the expression of CD4+T but also promoted the expression of CD8+T. The anti-inflammatory effect of moxibustion may be related to the regulation of T cell expression through the Tim-3/Gal-9 signaling pathway.

Proteomic signature of HIV-associated subclinical left atrial remodeling and incident heart failure

People living with HIV are at higher risk of heart failure and associated left atrial remodeling compared to people without HIV. Mechanisms are unclear but have been linked to inflammation and premature aging. Here we obtain plasma proteomics concurrently with cardiac magnetic resonance imaging in two independent study populations to identify parallels between HIV-related and aging-related immune dysfunction that could contribute to atrial remodeling and clinical heart failure. We discover a plasma proteomic signature that may in part reflect or contribute to HIV-associated atrial remodeling, many features of which are associated with older age and time to incident heart failure among an independent community-based cohort without HIV. This proteomic profile was statistically enriched for immune checkpoint proteins, tumor necrosis factor signaling, ephrin signaling, and extracellular matrix organization, identifying possible shared pathways in HIV and aging that may contribute to risk of heart failure.

Immune Checkpoints Are New Therapeutic Targets in Regulating Cardio-, and Cerebro-Vascular Diseases and CD4+Foxp3+ Regulatory T Cell Immunosuppression

Although previous reviews explored the roles of selected immune checkpoints (ICPs) in cardiovascular diseases (CVD) and cerebrovascular diseases from various perspectives, many related aspects have yet to be thoroughly reviewed and analyzed. Our comprehensive review addresses this gap by discussing the cellular functions of ICPs, focusing on the tissue-specific and microenvironment-localized transcriptomic and posttranslational regulation of ICP expressions, as well as their functional interactions with metabolic reprogramming. We also analyze how 14 pairs of ICPs, including CTLA-4/CD86-CD80, PD1-PDL-1, and TIGIT-CD155, regulate CVD pathogenesis. Additionally, the review covers the roles of ICPs in modulating CD4+Foxp3+ regulatory T cells (Tregs), T cells, and innate immune cells in various CVDs and cerebrovascular diseases. Furthermore, we outline seven immunological principles to guide the development of new ICP-based therapies for CVDs. This timely and thorough analysis of recent advancements and challenges provide new insights into the role of ICPs in CVDs, cerebrovascular diseases and Tregs, and will support the development of novel therapeutics strategies for these diseases.

Genetic factors in the pathogenesis of cardio-oncology

In recent years, with advancements in medicine, the survival period of patients with tumours has significantly increased. The adverse effects of tumour treatment on patients, especially cardiac toxicity, have become increasingly prominent. In elderly patients with breast cancer, treatment-related cardiovascular toxicity has surpassed cancer itself as the leading cause of death. Moreover, in recent years, an increasing number of novel antitumour drugs, such as multitargeted agents, antibody‒drug conjugates (ADCs), and immunotherapies, have been applied in clinical practice. The cardiotoxicity induced by these drugs has become more pronounced, leading to a complex and diverse mechanism of cardiac damage. The risks of unintended cardiovascular toxicity are increased by high-dose anthracyclines, immunotherapies, and concurrent radiation, in addition to traditional cardiovascular risk factors such as smoking, hypertension, diabetes, hyperlipidaemia, and obesity. However, these factors do not fully explain why only a subset of individuals experience treatment-related cardiac toxicity, whereas others with similar clinical features do not. Recent studies indicate that genetics play a significant role in susceptibility to the development of cardiovascular toxicity from cancer therapies. These genes are involved in drug metabolism, oxidative damage, cardiac dysfunction, and other processes. Moreover, emerging evidence suggests that epigenetics also plays a role in drug-induced cardiovascular toxicity. We conducted a review focusing on breast cancer as an example to help oncologists and cardiologists better understand the mechanisms and effects of genetic factors on cardiac toxicity. In this review, we specifically address the relationship between genetic alterations and cardiac toxicity, including chemotherapy-related genetic changes, targeted therapy-related genetic changes, and immune therapy-related genetic changes. We also discuss the role of epigenetic factors in cardiac toxicity. We hope that this review will improve the risk stratification of patients and enable therapeutic interventions that mitigate these unintended adverse consequences of life-saving cancer treatments.

Immune checkpoints in cardiac physiology and pathology: therapeutic targets for heart failure

Immune checkpoint molecules are physiological regulators of the adaptive immune response. Immune checkpoint inhibitors (ICIs), such as monoclonal antibodies targeting programmed cell death protein 1 or cytotoxic T lymphocyte-associated protein 4, have revolutionized cancer treatment and their clinical use is increasing. However, ICIs can cause various immune-related adverse events, including acute and chronic cardiotoxicity. Of these cardiovascular complications, ICI-induced acute fulminant myocarditis is the most studied, although emerging clinical and preclinical data are uncovering the importance of other ICI-related chronic cardiovascular complications, such as accelerated atherosclerosis and non-myocarditis-related heart failure. These complications could be more difficult to diagnose, given that they might only be present alongside other comorbidities. The occurrence of these complications suggests a potential role of immune checkpoint molecules in maintaining cardiovascular homeostasis, and disruption of physiological immune checkpoint signalling might thus lead to cardiac pathologies, including heart failure. Although inflammation is a long-known contributor to the development of heart failure, the therapeutic targeting of pro-inflammatory pathways has not been successful thus far. The increasingly recognized role of immune checkpoint molecules in the failing heart highlights their potential use as immunotherapeutic targets for heart failure. In this Review, we summarize the available data on ICI-induced cardiac dysfunction and heart failure, and discuss how immune checkpoint signalling is altered in the failing heart. Furthermore, we describe how pharmacological targeting of immune checkpoints could be used to treat heart failure.

Baricitinib protects ICIs-related myocarditis by targeting JAK1/STAT3 to regulate Macrophage polarization

PURPOSE

The emergence of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, but these drugs can also cause severe immune-related adverse effects (irAEs), including myocarditis. Researchers have become interested in exploring ways to mitigate this side effect, and one promising avenue is the use of baricitinib, a Janus kinase inhibitor known to have anti-inflammatory properties. This study aimed to examine the potential mechanism by which baricitinib in ICIs-related myocarditis.

METHODS

To establish an ICIs-related myocarditis model, BALB/c mice were administered murine cardiac troponin I (cTnI) peptide and anti-mouse programmed death 1 (PD-1) antibodies. Subsequently, baricitinib was administered to the mice via intragastric administration. Echocardiography, HE staining, and Masson staining were performed to evaluate myocardial functions, inflammation, and fibrosis. Immunofluorescence was used to detect macrophages in the cardiac tissue of the mice.In vitro experiments utilized raw264.7 cells to induce macrophage polarization using anti-PD-1 antibodies. Different concentrations of baricitinib were applied to assess cell viability, and the release of pro-inflammatory cytokines was measured. The activation of the JAK1/STAT3 signaling pathway was evaluated through western blot analysis.

RESULTS

Baricitinib demonstrated its ability to improve cardiac function and reduce cardiac inflammation, as well as fibrosis induced by ICIs. Mechanistically, baricitinib treatment promoted the polarization of macrophages towards the M2 phenotype. In vitro and in vivo experiments showed that anti-PD-1 promoted the release of inflammatory factors. However, treatment with baricitinib significantly inhibited the phosphorylation of JAK1 and STAT3. Additionally, the use of RO8191 reversed the effects of baricitinib, further confirming our findings.

CONCLUSION

Baricitinib demonstrated its potential as a protective agent against ICIs-related myocarditis by modulating macrophage polarization. These findings provide a solid theoretical foundation for the development of future treatments for ICIs-related myocarditis.

Inflammaging, immunosenescence, and cardiovascular aging: insights into long COVID implications

Aging leads to physiological changes, including inflammaging-a chronic low-grade inflammatory state with significant implications for various physiological systems, particularly for cardiovascular health. Concurrently, immunosenescence-the age-related decline in immune function, exacerbates vulnerabilities to cardiovascular pathologies in older individuals. Examining the dynamic connections between immunosenescence, inflammation, and cardiovascular aging, this mini-review aims to disentangle some of these interactions for a better understanding of their complex interplay. In the context of cardiovascular aging, the chronic inflammatory state associated with inflammaging compromises vascular integrity and function, contributing to atherosclerosis, endothelial dysfunction, arterial stiffening, and hypertension. The aging immune system's decline amplifies oxidative stress, fostering an environment conducive to atherosclerotic plaque formation. Noteworthy inflammatory markers, such as the high-sensitivity C-reactive protein, interleukin-6, interleukin-1β, interleukin-18, and tumor necrosis factor-alpha emerge as key players in cardiovascular aging, triggering inflammatory signaling pathways and intensifying inflammaging and immunosenescence. In this review we aim to explore the molecular and cellular mechanisms underlying inflammaging and immunosenescence, shedding light on their nuanced contributions to cardiovascular diseases. Furthermore, we explore the reciprocal relationship between immunosenescence and inflammaging, revealing a self-reinforcing cycle that intensifies cardiovascular risks. This understanding opens avenues for potential therapeutic targets to break this cycle and mitigate cardiovascular dysfunction in aging individuals. Furthermore, we address the implications of Long COVID, introducing an additional layer of complexity to the relationship between aging, immunosenescence, inflammaging, and cardiovascular health. Our review aims to stimulate continued exploration and advance our understanding within the realm of aging and cardiovascular health.

The Intriguing World of Vascular Remodeling, Angiogenesis, and Arteriogenesis

Vascular remodeling is a very general feature related to angiogenesis and arteriogenesis, which are involved in neovascularization processes [...].

Integrative analysis of bioinformatics and machine learning to identify cuprotosis-related biomarkers and immunological characteristics in heart failure

Backgrounds

Cuprotosis is a newly discovered programmed cell death by modulating tricarboxylic acid cycle. Emerging evidence showed that cuprotosis-related genes (CRGs) are implicated in the occurrence and progression of multiple diseases. However, the mechanism of cuprotosis in heart failure (HF) has not been investigated yet.

Methods

The HF microarray datasets GSE16499, GSE26887, GSE42955, GSE57338, GSE76701, and GSE79962 were downloaded from the Gene Expression Omnibus (GEO) database to identify differentially expressed CRGs between HF patients and nonfailing donors (NFDs). Four machine learning models were used to identify key CRGs features for HF diagnosis. The expression profiles of key CRGs were further validated in a merged GEO external validation dataset and human samples through quantitative reverse-transcription polymerase chain reaction (qRT-PCR). In addition, Gene Ontology (GO) function enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and immune infiltration analysis were used to investigate potential biological functions of key CRGs.

Results

We discovered nine differentially expressed CRGs in heart tissues from HF patients and NFDs. With the aid of four machine learning algorithms, we identified three indicators of cuprotosis (DLAT, SLC31A1, and DLST) in HF, which showed good diagnostic properties. In addition, their differential expression between HF patients and NFDs was confirmed through qRT-PCR. Moreover, the results of enrichment analyses and immune infiltration exhibited that these diagnostic markers of CRGs were strongly correlated to energy metabolism and immune activity.

Conclusions

Our study discovered that cuprotosis was strongly related to the pathogenesis of HF, probably by regulating energy metabolism-associated and immune-associated signaling pathways.

Circadian Effects on Vascular Immunopathologies

Circadian rhythms exert a profound impact on most aspects of mammalian physiology, including the immune and cardiovascular systems. Leukocytes engage in time-of-day-dependent interactions with the vasculature, facilitating the emigration to and the immune surveillance of tissues. This review provides an overview of circadian control of immune-vascular interactions in both the steady state and cardiovascular diseases such as atherosclerosis and infarction. Circadian rhythms impact both the immune and vascular facets of these interactions, primarily through the regulation of chemoattractant and adhesion molecules on immune and endothelial cells. Misaligned light conditions disrupt this rhythm, generally exacerbating atherosclerosis and infarction. In cardiovascular diseases, distinct circadian clock genes, while functioning as part of an integrated circadian system, can have proinflammatory or anti-inflammatory effects on these immune-vascular interactions. Here, we discuss the mechanisms and relevance of circadian rhythms in vascular immunopathologies.

Adipsin in the pathogenesis of cardiovascular diseases

Adipsin is an adipokine predominantly synthesized in adipose tissues and released into circulation. It is also known as complement factor-D (CFD), acting as the rate-limiting factor in the alternative complement pathway and exerting essential functions on the activation of complement system. The deficiency of CFD in humans is a very rare condition. However, complement overactivation has been implicated in the etiology of numerous disorders, including cardiovascular disease (CVD). Increased circulating level of adipsin has been reported to promote vascular derangements, systemic inflammation, and endothelial dysfunction. Prospective and case-control studies showed that this adipokine is directly associated with all-cause death and rehospitalization in patients with coronary artery disease. Adipsin has also been implicated in pulmonary arterial hypertension, abdominal aortic aneurysm, pre-eclampsia, and type-2 diabetes which is a major risk factor for CVD. Importantly, serum adipsin has been recognized as a unique prognostic marker for assessing cardiovascular diseases. At present, there is paucity of experimental evidence about the precise role of adipsin in the etiology of CVD. However, this mini review provides some insight on the contribution of adipsin in the pathogenesis of CVD and highlights its role on endothelial, smooth muscle and immune cells that mediate cardiovascular functions.

Proteomic Signature of HIV-Associated Subclinical Left Atrial Remodeling and Incident Heart Failure

Background

People living with HIV (PLWH) are at higher risk of heart failure (HF) and preceding subclinical cardiac abnormalities, including left atrial dilation, compared to people without HIV (PWOH). Hypothesized mechanisms include premature aging linked to chronic immune activation. We leveraged plasma proteomics to identify potential novel contributors to HIV-associated differences in indexed left atrial volume (LAVi) among PLWH and PWOH and externally validated identified proteomic signatures with incident HF among a cohort of older PWOH.

Methods

We performed proteomics (Olink Explore 3072) on plasma obtained concurrently with cardiac magnetic resonance imaging among PLWH and PWOH in the United States. Proteins were analyzed individually and as agnostically defined clusters. Cross-sectional associations with HIV and LAVi were estimated using multivariable regression with robust variance. Among an independent general population cohort, we estimated associations between identified signatures and LAVi using linear regression and incident HF using Cox regression.

Results

Among 352 participants (age 55±6 years; 25% female), 61% were PLWH (88% on ART; 73% with undetectable HIV RNA) and mean LAVi was 29±9 mL/m 2 . Of 2594 analyzed proteins, 439 were associated with HIV serostatus, independent of demographics, hepatitis C virus infection, renal function, and substance use (FDR<0.05). We identified 73 of these proteins as candidate contributors to the independent association between positive HIV serostatus and higher LAVi, enriched in tumor necrosis factor (TNF) signaling and immune checkpoint proteins regulating T cell, B cell, and NK cell activation. We identified one protein cluster associated with LAVi and HIV regardless of HIV viral suppression status, which comprised 42 proteins enriched in TNF signaling, ephrin signaling, and extracellular matrix (ECM) organization. This protein cluster and 30 of 73 individual proteins were associated with incident HF among 2273 older PWOH (age 68±9 years; 52% female; 8.5±1.4 years of follow-up).

Conclusion

Proteomic signatures that may contribute to HIV-associated LA remodeling were enriched in immune checkpoint proteins, cytokine signaling, and ECM organization. These signatures were also associated with incident HF among older PWOH, suggesting specific markers of chronic immune activation, systemic inflammation, and fibrosis may identify shared pathways in HIV and aging that contribute to risk of HF.

Interaction between NSCLC Cells, CD8+ T-Cells and Immune Checkpoint Inhibitors Potentiates Coagulation and Promotes Metabolic Remodeling-New Cues on CAT-VTE

BACKGROUND

Cancer-associated thrombosis (CAT) and venous thromboembolism (VTE) are frequent cancer-related complications associated with high mortality; thus, this urges the identification of predictive markers. Immune checkpoint inhibitors (ICIs) used in cancer immunotherapy allow T-cell activation against cancer cells. Retrospective studies showed increased VTE following ICI administration in some patients. Non-small cell lung cancer (NSCLC) patients are at high risk of thrombosis and thus, the adoption of immunotherapy, as a first-line treatment, seems to be associated with coagulation-fibrinolysis derangement.

METHODS

We pharmacologically modulated NSCLC cell lines in co-culture with CD8+ T-cells (TCD8+) and myeloid-derived suppressor cells (MDSCs), isolated from healthy blood donors. The effects of ICIs Nivolumab and Ipilimumab on NSCLC cell death were assessed by annexin V and propidium iodide (PI) flow cytometry analysis. The potential procoagulant properties were analyzed by in vitro clotting assays and enzyme-linked immunosorbent assays (ELISAs). The metabolic remodeling induced by the ICIs was explored by 1H nuclear magnetic resonance (NMR) spectroscopy.

RESULTS

Flow cytometry analysis showed that TCD8+ and ICIs increase cell death in H292 and PC-9 cells but not in A549 cells. Conditioned media from NSCLC cells exposed to TCD8+ and ICI induced in vitro platelet aggregation. In A549, Podoplanin (PDPN) levels increased with Nivolumab. In H292, ICIs increased PDPN levels in the absence of TCD8+. In PC-9, Ipilimumab decreased PDPN levels, this effect being rescued by TCD8+. MDSCs did not interfere with the effect of TCD8+ in the production of TF or PDPN in any NSCLC cell lines. The exometabolome showed a metabolic remodeling in NSCLC cells upon exposure to TCD8+ and ICIs.

CONCLUSIONS

This study provides some insights into the interplay of immune cells, ICIs and cancer cells influencing the coagulation status. ICIs are important promoters of coagulation, benefiting from TCD8+ mediation. The exometabolome analysis highlighted the relevance of acetate, pyruvate, glycine, glutamine, valine, leucine and isoleucine as biomarkers. Further investigation is needed to validate this finding in a cohort of NSCLC patients.

Broadening Horizons: Exploring mtDAMPs as a Mechanism and Potential Intervention Target in Cardiovascular Diseases

Cardiovascular diseases (CVDs) have been recognized as the leading cause of premature mortality and morbidity worldwide despite significant advances in therapeutics. Inflammation is a key factor in CVD progression. Once stress stimulates cells, they release cellular compartments known as damage-associated molecular patterns (DAMPs). Mitochondria can release mitochondrial DAMPs (mtDAMPs) to initiate an immune response when stimulated with cellular stress. Investigating the molecular mechanisms underlying the DAMPs that regulate CVD progression is crucial for improving CVDs. Herein, we discuss the composition and mechanism of DAMPs, the significance of mtDAMPs in cellular inflammation, the presence of mtDAMPs in different types of cells, and the main signaling pathways associated with mtDAMPs. Based on this, we determined the role of DAMPs in CVDs and the effects of mtDAMP intervention on CVD progression. By offering a fresh perspective and comprehensive insights into the molecular mechanisms of DAMPs, this review seeks to provide important theoretical foundations for developing drugs targeting CVDs.

Impact of Immunity on Coronary Artery Disease: An Updated Pathogenic Interplay and Potential Therapeutic Strategies

Coronary artery disease (CAD) is the leading cause of death worldwide. It is a result of the buildup of atherosclerosis within the coronary arteries. The role of the immune system in CAD is complex and multifaceted. The immune system responds to damage or injury to the arterial walls by initiating an inflammatory response. However, this inflammatory response can become chronic and lead to plaque formation. Neutrophiles, macrophages, B lymphocytes, T lymphocytes, and NKT cells play a key role in immunity response, both with proatherogenic and antiatherogenic signaling pathways. Recent findings provide new roles and activities referring to endothelial cells and vascular smooth muscle cells, which help to clarify the intricate signaling crosstalk between the involved actors. Research is ongoing to explore immunomodulatory therapies that target the immune system to reduce inflammation and its contribution to atherosclerosis. This review aims to summarize the pathogenic interplay between immunity and CAD and the potential therapeutic strategies, and explore immunomodulatory therapies that target the immune system to reduce inflammation and its contribution to atherosclerosis.

Immune interactions in pembrolizumab (PD-1 inhibitor) cancer therapy and cardiovascular complications

The use of immunotherapies like pembrolizumab (PEM) is increasingly common for the management of numerous cancer types. The use of PEM to bolster T-cell response against tumor growth is well documented. However, the interactions PEM has on other immune cells to facilitate tumor regression and clearance is unknown and warrants further investigation. In this review, we present literature findings that have reported the interactions of PEM in stimulating innate and adaptive immune cells, which enhance cytotoxic phenotypes. This triggers secretion of cytokines and chemokines, which have both beneficial and detrimental effects. We also describe how this leads to the development of rare but underreported occurrence of PEM-induced immune-related cardiovascular complications that arise suddenly and progress rapidly to debilitating and fatal consequences. This review encourages further research and investigation of PEM-induced cardiovascular complications and other immune cell interactions in patients with cancer. As PEM therapy in treating cancer types is expanding, we expect that this review will inform health care professionals of diverse specializations of medicine like dermatology (melanoma skin cancers), ophthalmology (eye cancers), and pathology (hematological malignancies) about PEM-induced cardiac complications.

CTLA-4 Pathway Is Instrumental in Giant Cell Arteritis

BACKGROUND

Giant cell arteritis (GCA) causes severe inflammation of the aorta and its branches and is characterized by intense effector T-cell infiltration. The roles that immune checkpoints play in the pathogenesis of GCA are still unclear. Our aim was to study the immune checkpoint interplay in GCA.

METHODS

First, we used VigiBase, the World Health Organization international pharmacovigilance database, to evaluate the relationship between GCA occurrence and immune checkpoint inhibitors treatments. We then further dissected the role of immune checkpoint inhibitors in the pathogenesis of GCA, using immunohistochemistry, immunofluorescence, transcriptomics, and flow cytometry on peripheral blood mononuclear cells and aortic tissues of GCA patients and appropriated controls.

RESULTS

Using VigiBase, we identified GCA as a significant immune-related adverse event associated with anti-CTLA-4 (cytotoxic T-lymphocyte-associated protein-4) but not anti-PD-1 (anti-programmed death-1) nor anti-PD-L1 (anti-programmed death-ligand 1) treatment. We further dissected a critical role for the CTLA-4 pathway in GCA by identification of the dysregulation of CTLA-4-derived gene pathways and proteins in CD4+ (cluster of differentiation 4) T cells (and specifically regulatory T cells) present in blood and aorta of GCA patients versus controls. While regulatory T cells were less abundant and activated/suppressive in blood and aorta of GCA versus controls, they still specifically upregulated CTLA-4. Activated and proliferating CTLA-4+ Ki-67+ regulatory T cells from GCA were more sensitive to anti-CTLA-4 (ipilimumab)-mediated in vitro depletion versus controls.

CONCLUSIONS

We highlighted the instrumental role of CTLA-4 immune checkpoint in GCA, which provides a strong rationale for targeting this pathway.

Inhibition of NETosis via PAD4 alleviated inflammation in giant cell myocarditis

Giant cell myocarditis (GCM) is a rare, usually rapidly progressive, and potentially fatal disease. Detailed inflammatory responses remain unknown, in particular the formation of multinucleate giant cells. We performed single-cell RNA sequencing analysis on 15,714 Cd45+ cells extracted from the hearts of GCM rats and normal rats. NETosis has been found to contribute to the GCM process. An inhibitor of NETosis, GSK484, alleviated GCM inflammation in vivo. MPO (a marker of neutrophils) and H3cit (a marker of NETosis) were expressed at higher levels in patients with GCM than in patients with DCM and healthy controls. Imaging mass cytometry analysis revealed that immune cell types within multinucleate giant cells included CD4+ T cells, CD8+ T cells, neutrophils, and macrophages but not B cells. We elucidated the role of NETosis in GCM pathogenesis, which may serve as a potential therapeutic target in the clinic.

Control of the post-infarct immune microenvironment through biotherapeutic and biomaterial-based approaches

Ischemic heart failure (IHF) is a leading cause of morbidity and mortality worldwide, for which heart transplantation remains the only definitive treatment. IHF manifests from myocardial infarction (MI) that initiates tissue remodeling processes, mediated by mechanical changes in the tissue (loss of contractility, softening of the myocardium) that are interdependent with cellular mechanisms (cardiomyocyte death, inflammatory response). The early remodeling phase is characterized by robust inflammation that is necessary for tissue debridement and the initiation of repair processes. While later transition toward an immunoregenerative function is desirable, functional reorientation from an inflammatory to reparatory environment is often lacking, trapping the heart in a chronically inflamed state that perpetuates cardiomyocyte death, ventricular dilatation, excess fibrosis, and progressive IHF. Therapies can redirect the immune microenvironment, including biotherapeutic and biomaterial-based approaches. In this review, we outline these existing approaches, with a particular focus on the immunomodulatory effects of therapeutics (small molecule drugs, biomolecules, and cell or cell-derived products). Cardioprotective strategies, often focusing on immunosuppression, have shown promise in pre-clinical and clinical trials. However, immunoregenerative therapies are emerging that often benefit from exacerbating early inflammation. Biomaterials can be used to enhance these therapies as a result of their intrinsic immunomodulatory properties, parallel mechanisms of action (e.g., mechanical restraint), or by enabling cell or tissue-targeted delivery. We further discuss translatability and the continued progress of technologies and procedures that contribute to the bench-to-bedside development of these critically needed treatments.

Gut microbiota, circulating inflammatory markers and metabolites, and carotid artery atherosclerosis in HIV infection

BACKGROUND

Alterations in gut microbiota have been implicated in HIV infection and cardiovascular disease. However, how gut microbial alterations relate to host inflammation and metabolite profiles, and their relationships with atherosclerosis, have not been well-studied, especially in the context of HIV infection. Here, we examined associations of gut microbial species and functional components measured by shotgun metagenomics with carotid artery plaque assessed by B-mode carotid artery ultrasound in 320 women with or at high risk of HIV (65% HIV +) from the Women's Interagency HIV Study. We further integrated plaque-associated microbial features with serum proteomics (74 inflammatory markers measured by the proximity extension assay) and plasma metabolomics (378 metabolites measured by liquid chromatography tandem mass spectrometry) in relation to carotid artery plaque in up to 433 women.

RESULTS

Fusobacterium nucleatum, a potentially pathogenic bacteria, was positively associated with carotid artery plaque, while five microbial species (Roseburia hominis, Roseburia inulinivorans, Johnsonella ignava, Odoribacter splanchnicus, Clostridium saccharolyticum) were inversely associated with plaque. Results were consistent between women with and without HIV. Fusobacterium nucleatum was positively associated with several serum proteomic inflammatory markers (e.g., CXCL9), and the other plaque-related species were inversely associated with proteomic inflammatory markers (e.g., CX3CL1). These microbial-associated proteomic inflammatory markers were also positively associated with plaque. Associations between bacterial species (especially Fusobacterium nucleatum) and plaque were attenuated after further adjustment for proteomic inflammatory markers. Plaque-associated species were correlated with several plasma metabolites, including the microbial metabolite imidazole-propionate (ImP), which was positively associated with plaque and several pro-inflammatory markers. Further analysis identified additional bacterial species and bacterial hutH gene (encoding enzyme histidine ammonia-lyase in ImP production) associated with plasma ImP levels. A gut microbiota score based on these ImP-associated species was positively associated with plaque and several pro-inflammatory markers.

CONCLUSION

Among women living with or at risk of HIV, we identified several gut bacterial species and a microbial metabolite ImP associated with carotid artery atherosclerosis, which might be related to host immune activation and inflammation. Video Abstract.

T-cell receptor signaling modulated by the co-receptors: Potential targets for stroke treatment

Stroke is a severe and life-threatening disease, necessitating more research on new treatment strategies. Infiltrated T lymphocytes, an essential adaptive immune cell with extensive effector function, are crucially involved in post-stroke inflammation. Immediately after the initiation of the innate immune response triggered by microglia/macrophages, the adaptive immune response associated with T lymphocytes also participates in the complex pathophysiology of stroke and partially informs the outcome of stroke. Preclinical and clinical studies have revealed the conflicting roles of T cells in post-stroke inflammation and as potential therapeutic targets. Therefore, exploring the mechanisms that underlie the adaptive immune response associated with T lymphocytes in stroke is essential. The T-cell receptor (TCR) and its downstream signaling regulate T lymphocyte differentiation and activation. This review comprehensively summarizes the various molecules that regulate TCR signaling and the T-cell response. It covers both the co-stimulatory and co-inhibitory molecules and their roles in stroke. Because immunoregulatory therapies targeting TCR and its mediators have achieved great success in some proliferative diseases, this article also summarizes the advances in therapeutic strategies related to TCR signaling in lymphocytes after stroke, which can facilitate translation. DATA AVAILABILITY: No data was used for the research described in the article.

CAR T Cell Therapy: A Versatile Living Drug

After seeing a dramatic increase in the development and use of immunotherapy and precision medicine over the past few decades, oncological care now embraces the start of the adoptive cell therapy (ACT) era. This impulse towards a new treatment paradigm has been led by chimeric antigen receptor (CAR) T cells, the only type of ACT medicinal product to be commercialized so far. Brought about by an ever-growing understanding of cellular engineering, CAR T cells are T lymphocytes genetically modified with an appropriate DNA construct, which endows them with expression of a CAR, a fusion protein between a ligand-specific recognition domain, often an antibody-like structure, and the activating signaling domain of the T cell receptor. Through this genetic enhancement, CAR T cells are engineered from a cancer patient’s own lymphocytes to better target and kill their cancer cells, and the current amassed data on clinical outcomes point to a stream of bright developments in the near future. Herein, from concept design and present-day manufacturing techniques to pressing hurdles and bright discoveries around the corner, we review and thoroughly describe the state of the art in CAR T cell therapy.

T cell co-stimulatory and co-inhibitory pathways in atopic dermatitis

The use of immune checkpoint inhibitors (ICIs) targeting the T cell inhibitory pathways has revolutionized cancer treatment. However, ICIs might induce progressive atopic dermatitis (AD) by affecting T cell reactivation. The critical role of T cells in AD pathogenesis is widely known. T cell co-signaling pathways regulate T cell activation, where co-signaling molecules are essential for determining the magnitude of the T cell response to antigens. Given the increasing use of ICIs in cancer treatment, a timely overview of the role of T cell co-signaling molecules in AD is required. In this review, we emphasize the importance of these molecules involved in AD pathogenesis. We also discuss the potential of targeting T cell co-signaling pathways to treat AD and present the unresolved issues and existing limitations. A better understanding of the T cell co-signaling pathways would aid investigation of the mechanism, prognosis evaluation, and treatment of AD.

A Predictive Disease Risk Model for Ankylosing Spondylitis: Based on Integrated Bioinformatic Analysis and Identification of Potential Biomarkers Most Related to Immunity

Background

The pathogenesis of ankylosing spondylitis (AS) is still not clear, and immune-related genes have not been systematically explored in AS. The purpose of this paper was to identify the potential early biomarkers most related to immunity in AS and develop a predictive disease risk model with bioinformatic methods and the Gene Expression Omnibus database (GEO) to improve diagnostic and therapeutic efficiency.

Methods

To identify differentially expressed genes and create a gene coexpression network between AS and healthy samples, we downloaded the AS-related datasets GSE25101 and GSE73754 from the GEO database and employed weighted gene coexpression network analysis (WGCNA). We used the GSVA, GSEABase, limma, ggpubr, and reshape2 packages to score immune data and investigated the links between immune cells and immunological functions by using single-sample gene set enrichment analysis (ssGSEA). The value of the core gene set and constructed model for early AS diagnosis was investigated by using receiver operating characteristic (ROC) curve analysis.

Results

Biological function and immune score analyses identified central genes related to immunity, key immune cells, key related pathways, gene modules, and the coexpression network in AS. Granulysin (GNLY), Granulysin (GZMK), CX3CR1, IL2RB, dysferlin (DYSF), and S100A12 may participate in AS development through NK cells, CD8⁺ T cells, Th1 cells, and other immune cells and represent potential biomarkers for the early diagnosis of AS occurrence and progression. Furthermore, the T cell coinhibitory pathway may be involved in AS pathogenesis.

Conclusion

The AS disease risk model constructed based on immune-related genes can guide clinical diagnosis and treatment and may help in the development of personalized immunotherapy.

Immune checkpoint inhibitor-induced myocarditis with myasthenia gravis overlap syndrome: A case report and literature review

RATIONALE

The therapeutic value of immune checkpoint inhibitors (ICIs) in a variety of tumors has been found and recognized, and although ICIs have improved the prognosis of many patients with advanced tumors, these drugs sometimes cause immune-related adverse events (irAEs).

PATIENT CONCERNS

We report a 67-year-old woman with advanced rectal endocrine tumor. Ten days after receiving two cycles of treatment with camrelizumab combined with http://www.baidu.com/link?url=shAWG4LYTwwBcZAEb6pLb6DkDndJR2tUgOfFiWAkOf0hS-_sj2jjSLBwYaxSiHY3r6yPj31Lp2DCP-7q3w7ho5HIV46V4fbIShFyUY7Cbka sorafenib, the patient suddenly suffered from chest tightness, shortness of breath and progressive aggravation of limb weakness, the high-sensitivity cardiac troponin T (hs-cTnT) was elevated to 3015pg/mL and N-terminal pro-B-type natriuretic peptide (NT-proBNP) up to 5671pg/mL, and creatine kinase (CK) was 1419U/L.

DIAGNOSIS AND INTERVENTIONS

The patient was diagnosed as immune checkpoint inhibitor-induced myocarditis with myasthenia gravis overlap syndrome. The patient was transferred to the intensive care unit (ICU) in time and given oxygen inhalation, glucocorticoids, immunoglobulin and anticholinesterase drugs, and other related treatments.

OUTCOMES

After 2 weeks, the symptoms of myasthenia gravis (MG) were relieved, and the level of myocardial injury markers decreased significantly, but it was still at a high level. The patient's family refused further treatment, and the patient died soon after.

LESSONS

In this paper, Through the report and follow-up analysis of this case, this paper recognizes that the early correct understanding and evaluation of this fulminant and fatal irAEs and the reasonable treatment of patients are very important for the prognosis of patients.

Anti‐thymocyte globulin‐mediated immunosenescent alterations of T cells in kidney transplant patients

Objectives

Kidney transplant (KT) is the most effective treatment for end‐stage renal disease. The immunosuppressant anti‐thymocyte globulin (ATG) has been applied for induction therapy to reduce the risk of acute transplant rejection for patients at high immunological risk. Despite its putative role in replicative stress during immune reconstitution, the effects of ATG on T‐cell immunosenescent changes remain to be understood.

Methods

Phenotypic and functional features of senescent T cells were examined by flow cytometry in 116 healthy controls (HC) and 95 KT patients for comparative analysis according to ATG treatment and CMV reactivation. The TCR repertoire was analysed in peripheral blood mononuclear cells (PBMCs) of KT patients.

Results

T cells of KT patients treated with ATG (ATG⁺) show typical immunosenescent features, accumulation of CD28⁻, CD85j⁺ or CD57⁺ T cells, and imbalance of functional T‐cell subsets, compared with untreated KT patients (ATG⁻). Plasma IL‐15 and CMV‐IgG levels were higher in KT patients than in HCs, and the IL‐15 level positively correlated with the frequency of CD28⁻ T cells in KT patients. ATG⁺ patients had a higher prevalence of CMV reactivation, which is associated with an increased frequency of CD28⁻ T cells. As a result, ATG⁺ patients had expanded CMV‐specific T cells and decreased TCR diversity. However, proliferation, cytokine‐producing capacity and polyfunctionality of T cells were preserved in ATG⁺ patients.

Conclusion

Our findings suggest that ATG treatment contributes to the accumulation of senescent T cells, which may have lifelong clinical implications in KT patients. Thus, these patients require long‐term and comprehensive immune monitoring.

A novel Nanocellulose-Gelatin-AS-IV external stent resists EndMT by activating autophagy to prevent restenosis of grafts

Vein grafts are widely used for coronary artery bypass grafting and hemodialysis access, but restenosis remains the "Achilles' heel" of these treatments. An extravascular stent is one wrapped around the vein graft and provides mechanical strength; it can buffer high arterial pressure and secondary vascular dilation of the vein to prevent restenosis. In this study, we developed a novel Nanocellulose-gelatin hydrogel, loaded with the drug Astragaloside IV (AS-IV) as an extravascular scaffold to investigate its ability to reduce restenosis. We found that the excellent physical and chemical properties of the drug AS-IV loaded Nanocellulose-gelatin hydrogel external stent limit graft vein expansion and make the stent biocompatible. We also found it can prevent restenosis by resisting endothelial-to-mesenchymal transition (EndMT) in vitro. It does so by activating autophagy, and AS-IV can enhance this effect both in vivo and in vitro. This study has added to existing research on the mechanism of extravascular stents in preventing restenosis of grafted veins. Furthermore, we have developed a novel extravascular stent for the prevention and treatment of restenosis. This will help optimize the clinical treatment plan of external stents and improve the prognosis in patients with vein grafts.

•

The NC-Gelatin extravascular stent has suitable physicochemical properties to prevent restenosis of the grafted veins.

•

The NC-Gelatin extravascular stent has excellent biocompatibility, which is critical for grafting veins.

•

The NC-Gelatin extravascular stent prevents restenosis by activating autophagy against EndMT.

•

AS-IV can enhance the effect of the stent to activate autophagy against EndMT.

Maternal Immune Cell and Cytokine Profiles to Predict Cardiovascular Risk Six Months after Preeclampsia

Women who develop preeclampsia (PE) are at high risk for cardiovascular disease (CVD). Early identification of women with PE who may benefit the most from early cardiovascular risk screening and interventions remains challenging. Our objective was to assess whether cytokine and immune cell profiles after PE are helpful in distinguishing women at low and high CVD risk at 6-months postpartum. Individuals who developed PE were followed for immune cell phenotyping and plasma cytokine quantification at delivery, at 3-months, and at 6-months postpartum. Lifetime CVD risk was assessed at 6-months postpartum, and the immune cell and cytokine profiles were compared between risk groups at each time point. Among 31 participants, 18 (58.1%) exhibited high CVD-risk profiles at 6-months postpartum. The proportion of circulating NK-cells was significantly lower in high-risk participants at delivery (p = 0.04). At 3-months postpartum, high-risk participants exhibited a lower proportion of FoxP3⁺ regulatory T-cells (p = 0.01), a greater proportion of CD8⁺ T cells (p = 0.02) and a lower CD4⁺:CD8⁺ ratio (p = 0.02). There were no differences in immune cell populations at 6-months postpartum. There were no differences in plasma cytokines levels between risk groups at any time point. Subtle differences in immune cell profiles may help distinguish individuals at low and high CVD risk in the early postpartum period and warrants further investigation.

Computational Discovery of Cancer Immunotherapy Targets by Intercellular CRISPR Screens

Cancer immunotherapy targets the interplay between immune and cancer cells. In particular, interactions between cytotoxic T lymphocytes (CTLs) and cancer cells, such as PD-1 (PDCD1) binding PD-L1 (CD274), are crucial for cancer cell clearance. However, immune checkpoint inhibitors targeting these interactions are effective only in a subset of patients, requiring the identification of novel immunotherapy targets. Genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening in either cancer or immune cells has been employed to discover regulators of immune cell function. However, CRISPR screens in a single cell type complicate the identification of essential intercellular interactions. Further, pooled screening is associated with high noise levels. Herein, we propose intercellular CRISPR screens, a computational approach for the analysis of genome-wide CRISPR screens in every interacting cell type for the discovery of intercellular interactions as immunotherapeutic targets. We used two publicly available genome-wide CRISPR screening datasets obtained while triple-negative breast cancer (TNBC) cells and CTLs were interacting. We analyzed 4825 interactions between 1391 ligands and receptors on TNBC cells and CTLs to evaluate their effects on CTL function. Intercellular CRISPR screens discovered targets of approved drugs, a few of which were not identifiable in single datasets. To evaluate the method's performance, we used data for cytokines and costimulatory molecules as they constitute the majority of immunotherapeutic targets. Combining both CRISPR datasets improved the recall of discovering these genes relative to using single CRISPR datasets over two-fold. Our results indicate that intercellular CRISPR screens can suggest novel immunotherapy targets that are not obtained through individual CRISPR screens. The pipeline can be extended to other cancer and immune cell types to discover important intercellular interactions as potential immunotherapeutic targets.

Molecular Mechanisms of Tumor Immunomodulation in the Microenvironment of Colorectal Cancer

Colorectal cancer remains one of the most important health challenges in our society. The development of cancer immunotherapies has fostered the need to better understand the anti-tumor immune mechanisms at play in the tumor microenvironment and the strategies by which the tumor escapes them. In this review, we provide an overview of the molecular interactions that regulate tumor inflammation. We particularly discuss immunomodulatory cell-cell interactions, cell-soluble factor interactions, cell-extracellular matrix interactions and cell-microbiome interactions. While doing so, we highlight relevant examples of tumor immunomodulation in colorectal cancer.

Immunotherapeutic Strategies in Cancer and Atherosclerosis-Two Sides of the Same Coin

The development and clinical approval of immunotherapies has revolutionized cancer therapy. Although the role of adaptive immunity in atherogenesis is now well-established and several immunomodulatory strategies have proven beneficial in preclinical studies, anti-atherosclerotic immunotherapies available for clinical application are not available. Considering that adaptive immune responses are critically involved in both carcinogenesis and atherogenesis, immunotherapeutic approaches for the treatment of cancer and atherosclerosis may exert undesirable but also desirable side effects on the other condition, respectively. For example, the high antineoplastic efficacy of immune checkpoint inhibitors, which enhance effector immune responses against tumor cells by blocking co-inhibitory molecules, was recently shown to be constrained by substantial proatherogenic properties. In this review, we outline the specific role of immune responses in the development of cancer and atherosclerosis. Furthermore, we delineate how current cancer immunotherapies affect atherogenesis and discuss whether anti-atherosclerotic immunotherapies may similarly have an impact on carcinogenesis.

Effects of Metformin in Heart Failure: From Pathophysiological Rationale to Clinical Evidence

Type 2 diabetes mellitus (T2DM) is a worldwide major health burden and heart failure (HF) is the most common cardiovascular (CV) complication in affected patients. Therefore, identifying the best pharmacological approach for glycemic control, which is also useful to prevent and ameliorate the prognosis of HF, represents a crucial issue. Currently, the choice is between the new drugs sodium/glucose co-transporter 2 inhibitors that have consistently shown in large CV outcome trials (CVOTs) to reduce the risk of HF-related outcomes in T2DM, and metformin, an old medicament that might end up relegated to the background while exerting interesting protective effects on multiple organs among which include heart failure. When compared with other antihyperglycemic medications, metformin has been demonstrated to be safe and to lower morbidity and mortality for HF, even if these results are difficult to interpret as they emerged mainly from observational studies. Meta-analyses of randomized controlled clinical trials have not produced positive results on the risk or clinical course of HF and sadly, large CV outcome trials are lacking. The point of force of metformin with respect to new diabetic drugs is the amount of data from experimental investigations that, for more than twenty years, still continues to provide mechanistic explanations of the several favorable actions in heart failure such as, the improvement of the myocardial energy metabolic status by modulation of glucose and lipid metabolism, the attenuation of oxidative stress and inflammation, and the inhibition of myocardial cell apoptosis, leading to reduced cardiac remodeling and preserved left ventricular function. In the hope that specific large-scale trials will be carried out to definitively establish the metformin benefit in terms of HF failure outcomes, we reviewed the literature in this field, summarizing the available evidence from experimental and clinical studies reporting on effects in heart metabolism, function, and structure, and the prominent pathophysiological mechanisms involved.

Development and validation of a supervised deep learning algorithm for automated whole-slide programmed death-ligand 1 tumour proportion score assessment in non-small cell lung cancer

AIMS

Immunohistochemical programmed death-ligand 1 (PD-L1) staining to predict responsiveness to immunotherapy in patients with advanced non-small cell lung cancer (NSCLC) has several drawbacks: a robust gold standard is lacking, and there is substantial interobserver and intraobserver variance, with up to 20% discordance around cutoff points. The aim of this study was to develop a new deep learning-based PD-L1 tumour proportion score (TPS) algorithm, trained and validated on a routine diagnostic dataset of digitised PD-L1 (22C3, laboratory-developed test)-stained samples.

METHODS AND RESULTS

We designed a fully supervised deep learning algorithm for whole-slide PD-L1 assessment, consisting of four sequential convolutional neural networks (CNNs), using aiforia create software. We included 199 whole slide images (WSIs) of 'routine diagnostic' histology samples from stage IV NSCLC patients, and trained the algorithm by using a training set of 60 representative cases. We validated the algorithm by comparing the algorithm TPS with the reference score in a held-out validation set. The algorithm had similar concordance with the reference score (79%) as the pathologists had with one another (75%). The intraclass coefficient was 0.96 and Cohen's κ coefficient was 0.69 for the algorithm. Around the 1% and 50% cutoff points, concordance was also similar between pathologists and the algorithm.

CONCLUSIONS

We designed a new, deep learning-based PD-L1 TPS algorithm that is similarly able to assess PD-L1 expression in daily routine diagnostic cases as pathologists. Successful validation on routine diagnostic WSIs and detailed visual feedback show that this algorithm meets the requirements for functioning as a 'scoring assistant'.

Immunity in Atherosclerosis: Focusing on T and B Cells

Atherosclerosis is the major cause of the development of cardiovascular disease, which, in turn, is one of the leading causes of mortality worldwide. From the point of view of pathogenesis, atherosclerosis is an extremely complex disease. A huge variety of processes, such as violation of mitophagy, oxidative stress, damage to the endothelium, and others, are involved in atherogenesis; however, the main components of atherogenesis are considered to be inflammation and alterations of lipid metabolism. In this review, we want to focus on inflammation, and more specifically on the cellular elements of adaptive immunity, T and B cells. It is known that various T cells are widely represented directly in atherosclerotic plaques, while B cells can be found, for example, in the adventitia layer. Of course, such widespread and well-studied cells have attracted attention as potential therapeutic targets for the treatment of atherosclerosis. Various approaches have been developed and tested for their efficacy.

Anti-inflammatory and Immunomodulatory Therapies in Atherosclerosis

Hypercholesterolemia is a major risk factor in atherosclerosis development and lipid-lowering drugs (i.e., statins) remain the treatment of choice. Despite effective reduction of LDL cholesterol in patients, a residual cardiovascular risk persists in some individuals, highlighting the need for further therapeutic intervention. Recently, the CANTOS trial paved the way toward the development of specific therapies targeting inflammation, a key feature in atherosclerosis progression. The pre-existence of multiple drugs modulating both innate and adaptive immune responses has significantly accelerated the number of translational studies applying these drugs to atherosclerosis. Additional preclinical research has led to the discovery of new therapeutic targets, offering promising perspectives for the treatment and prevention of atherosclerosis. Currently, both drugs with selective targeting and broad unspecific anti-inflammatory effects have been tested. In this chapter, we aim to give an overview of current advances in immunomodulatory treatment approaches for atherosclerotic cardiovascular diseases.

B Cells in Atherosclerosis: Mechanisms and Potential Clinical Applications

•

B cells regulate atherosclerotic plaque formation through production of antibodies and cytokines, and effects are subset specific (B1 and B2).

•

Putative human atheroprotective B1 cells function similarly to murine B1 in their spontaneous IgM antibody production. However, marker strategies in identifying human and murine B1 are different.

•

IgM antibody to oxidation specific epitopes produced by B1 cells associate with human coronary artery disease.

•

Neoantigen immunization may be a promising strategy for atherosclerosis vaccine development, but further study to determine relevant antigens still need to be done.

•

B-cell–targeted therapies, used in treating autoimmune diseases as well as lymphoid cancers, might have potential applications in treating cardiovascular diseases. Short- and long-term cardiovascular effects of these agents need to be assessed.

Because atherosclerotic cardiovascular disease is a leading cause of death worldwide, understanding inflammatory processes underpinning its pathology is critical. B cells have been implicated as a key immune cell type in regulating atherosclerosis. B-cell effects, mediated by antibodies and cytokines, are subset specific. In this review, we focus on elaborating mechanisms underlying subtype-specific roles of B cells in atherosclerosis and discuss available human data implicating B cells in atherosclerosis. We further discuss potential B cell–linked therapeutic approaches, including immunization and B cell–targeted biologics. Given recent evidence strongly supporting a role for B cells in human atherosclerosis and the expansion of immunomodulatory agents that affect B-cell biology in clinical use and clinical trials for other disorders, it is important that the cardiovascular field be cognizant of potential beneficial or untoward effects of modulating B-cell activity on atherosclerosis.

Reversing T-cell exhaustion in immunotherapy: a review on current approaches and limitations

Introduction:T cell functions are altered during chronic viral infections and tumor development. This is mainly manifested by significant changes in T cells' epigenetic and metabolic landscapes, pushing them into an 'exhausted' state. Reversing this T cell exhaustion has been emerging as a 'game-changing' therapeutic approach against cancer and chronic viral infection.Areas covered:This review discusses the cellular pathways related to T cell exhaustion, and the clinical development and possible cellular targets that can be exploited therapeutically to reverse this exhaustion. We searched various databases (e.g. Google Scholar, PubMed, Elsevier, and other scientific database sites) using the keywords T cell exhaustion, T cell activation, co-inhibitory receptors, and reversing T cell exhaustion.Expert opinion:The discovery of the immune checkpoints pathways represents a significant milestone toward understanding and reversing T cell exhaustion. Antibodies that target these pathways have already demonstrated promising activities in reversing T cell exhaustion. Nevertheless, there are still many associated limitations. In this context, next-generation alternatives are on the horizon. This includes the use of small molecules to block the immune checkpoints' receptors, combining them with other treatments, and identifying novel, safer and more effective immunotherapeutic targets.

Immunomodulatory mAbs as Tools to Investigate on Cis-Interaction of PD-1/PD-L1 on Tumor Cells and to Set Up Methods for Early Screening of Safe and Potent Combinatorial Treatments

Simple Summary

A novel challenge in cancer immunotherapy is the identification of the most potent combinations of immunomodulatory mAbs that are capable of maximizing therapeutic benefits while minimizing irAEs. We set up an in vitro system to quickly predict the efficacy and eventual cardiotoxic side effects of combinatorial treatments, thus allowing for the early screening of most potent and safe combinatorial therapeutic regimens for both validated and emerging immunomodulatory mAbs against different immune checkpoints (ICs). Furthermore, we provide for the first time evidence on cis-interactions of ICs in tumor cells.

Abstract

Antibodies targeting Immune Checkpoints (IC) on tumor infiltrating lymphocytes improve immune responses against cancer. Recently, the expression of some ICs has also been reported on cancer cells. We used the clinically validated Ipilimumab and Nivolumab and other novel human antibodies targeting Cytotoxic T- lymphocyte-antigen 4 (CTLA-4), Programmed Death receptor-1 (PD-1) and Programmed Death Ligand 1 (PD-L1) to shed light on the functions of these ICs in cancer cells. We show here for the first time that all these antagonistic mAbs are able to reduce Erk phosphorylation and, unexpectedly, to induce a significant increase of ICs expression on tumor cells, involving a hyperphosphorylation of NF-kB. On the contrary, agonistic PD-L1 and PD-1 recombinant proteins showed opposite effects by leading to a significant reduction of PD-1 and PD-L1, thus also suggesting the existence of a crosstalk in tumor cells between multiple ICs. Since the immunomodulatory mAbs show their higher anti-tumor efficacy by activating lymphocytes against cancer cells, we also investigated whether it was possible to identify the most efficient combinations of immunomodulatory mAbs for achieving potent anti-tumor efficacy associated with the lowest adverse side effects by setting up novel simple and predictive in vitro models based on co-cultures of tumor cells or human fetal cardiomyocytes with lymphocytes. We demonstrate here that novel combinations of immunomodulatory mAbs with more potent anti-cancer activity than Ipilimumab and Nivolumab combination can be identified with no or lower cardiotoxic side effects. Thus, we propose these co-cultures-based assays as useful tools to test also other combinatorial treatments of emerging immunomodulatory mAbs against different ICs for the early screening of most potent and safe combinatorial therapeutic regimens.

Immune Checkpoint Inhibitors and Atherosclerotic Vascular Events in Cancer Patients

In clinical trials and meta-analysis, atherosclerotic vascular events (AVEs) during treatment with immune-checkpoint inhibitors (ICIs) have been reported with low incidence. However, preclinical data suggest that these drugs can promote atherosclerosis inflammation and progression of atherosclerosis plaques, and there is now growing and convincing evidence from retrospective studies that ICIs increase the risk of atherosclerotic vascular events including arterial thrombosis, myocardial infarction and ischemic stroke. Prospective studies are needed to increase knowledge on long-term effect of ICIs or their combinations with other cardio-toxic drugs, but in the meantime a careful assessment and optimization of cardiovascular risk factors among patients treated with ICIs is advisable.

Endothelial Barrier Function and Leukocyte Transmigration in Atherosclerosis

The vascular endothelium is a highly specialized barrier that controls passage of fluids and migration of cells from the lumen into the vessel wall. Endothelial cells assist leukocytes to extravasate and despite the variety in the specific mechanisms utilized by different leukocytes to cross different vascular beds, there is a general principle of capture, rolling, slow rolling, arrest, crawling, and ultimately diapedesis via a paracellular or transcellular route. In atherosclerosis, the barrier function of the endothelium is impaired leading to uncontrolled leukocyte extravasation and vascular leakage. This is also observed in the neovessels that grow into the atherosclerotic plaque leading to intraplaque hemorrhage and plaque destabilization. This review focuses on the vascular endothelial barrier function and the interaction between endothelial cells and leukocytes during transmigration. We will discuss the role of endothelial dysfunction, transendothelial migration of leukocytes and plaque angiogenesis in atherosclerosis.

Pharmacological and Genetic Inhibition of PD-1 Demonstrate an Important Role of PD-1 in Ischemia-Induced Skeletal Muscle Inflammation, Oxidative Stress, and Angiogenesis

Angiogenesis is an important process under both physiological and pathophysiological conditions. Here we investigated the role and the underlying mechanism of PD-1 in hindlimb ischemia-induced inflammation and angiogenesis in mice. We found that inhibition of PD-1 by genetic PD-1 knockout or pharmacological PD-1 blocking antibodies dramatically attenuated hindlimb blood perfusion, angiogenesis, and exercise capacity in mice after femoral artery ligation. Mechanistically, we found that PD-1 knockout significantly exacerbated ischemia-induced muscle oxidative stress, leukocyte infiltration and IFN-γ production before abnormal angiogenesis in these mice. In addition, we found that the percentages of IFN-γ positive macrophages and CD8 T cells were significantly increased in P-1 knockout mice after hindlimb ischemia. Macrophages were the major leukocyte subset infiltrated in skeletal muscle, which were responsible for the enhanced muscle leukocyte-derived IFN-γ production in PD-1 knockout mice after hindlimb ischemia. Moreover, we demonstrated that IFN-γ significantly attenuated vascular endothelial cell proliferation, tube formation and migration in vitro. IFN-γ also significantly enhanced vascular endothelial cell apoptosis. In addition, the total number of TNF-α positive leukocytes/muscle weight were significantly increased in PD-1^-/- mice after hindlimb ischemia. These data indicate that PD-1 exerts an important role in ischemia-induced muscle inflammation and angiogenesis.

T cell co-stimulator inducible co-stimulatory (ICOS) exerts potential anti-atherosclerotic roles through downregulation of vascular smooth muscle phagocytosis and proliferation

Background

Atherosclerosis (AS) is a chronic inflammatory disease. The role of the immune system in the etiology of the disease, particularly T cells, has been widely studied and is well established. T cell activation directly regulates co-signaling molecules present in immune synapses. Targeting one or several of these co-signaling molecules can inhibit T cell-mediated inflammation and delay or reduce AS. In recent years, this strategy has increasingly become a research focus. As such, we explored the role and therapeutic potential of the T cell co-stimulatory molecule inducible co-stimulatory (ICOS) in AS.

Methods

We compared the expression of ICOS in early AS lesions occurring in ApoE-deficient (ApoE-KO) rats fed a fat-diet and wild type (WT) rats fed the same diet. Eight-week old ApoE-KO and WT rats [ApoE-KO(0) and WT(0)] were fed a high-fat diet for 16 weeks [ApoE-KO(16) and WT(16)]. ICOS expression in aortic tissues was analyzed by quantitative real-time PCR, western blot, and confocal microscopy. The effect of ICOS overexpression in a transfected human T cell line on the phagocytosis and proliferation of co-cultured human aortic smooth muscle cells (HASMCs) was studied in vitro.

Results

Compared with WT(0), ApoE-KO(0), and WT(16) rats, ICOS expression in ApoE-KO(16) rats was significantly down-regulated both at the mRNA and protein levels. In vitro experiments indicated that ICOS overexpression reduces phagocytosis and proliferation by HASMCs, and may therefore produce an anti-atherosclerotic effect.

Conclusions

The immune synaptic co-signaling molecule ICOS has an anti-atherosclerotic effect through inhibition of HASMC phagocytosis and proliferation, and can be used to delay plaque formation during the early stages of AS.

Circulating Exosomes Control CD4+ T Cell Immunometabolic Functions via the Transfer of miR-142 as a Novel Mediator in Myocarditis

CD4+ T cells undergo immunometabolic activation to mount an immunogenic response during experimental autoimmune myocarditis (EAM). Exosomes are considered key messengers mediating multiple T cell functions in autoimmune responses. However, the role of circulating exosomes in EAM immunopathogenesis and CD4+ T cell dysfunction remains elusive. Our objective was to elucidate the mechanism of action for circulating exosomes in EAM pathogenesis. We found that serum exosomes harvested from EAM mice induced CD4+ T cell immunometabolic dysfunction. Treatment with the exosome inhibitor GW4869 protected mice from developing EAM, underlying that exosomes are indispensable for the pathogenesis of EAM. Furthermore, by transfer of EAM exosomes, we confirmed that circulating exosomes initiate the T cell pathological immune response, driving the EAM pathological process. Mechanistically, EAM-circulating exosomes selectively loaded abundant microRNA (miR)-142. We confirmed methyl-CpG binding domain protein 2 (MBD2) and suppressor of cytokine signaling 1 (SOCS1) as functional target genes of miR-142. The miR-142/MBD2/MYC and miR-142/SOCS1 communication axes are critical to exosome-mediated immunometabolic turbulence. Moreover, the in vivo injection of the miR-142 inhibitor alleviated cardiac injury in EAM mice. This effect was abrogated by pretreatment with EAM exosomes. Collectively, our results indicate a newly endogenous mechanism whereby circulating exosomes regulate CD4+ T cell immunometabolic dysfunction and EAM pathogenesis via cargo miR-142.

Inflammation and hypertension development: A longitudinal analysis of the African-PREDICT study

Background

The role of inflammation in the development of hypertension remains incompletely understood. While single inflammatory mediators have been shown to associate with changes in blood pressure (ΔBP), the role of clusters of inflammatory mediators has been less comprehensively explored. We therefore determined whether individual or clusters of inflammatory mediators from a large biomarker panel were associated with ΔBP over 4.5 years, in young healthy adults.

Methods

We included 358 adults (white, n = 156; black, n = 202) with detailed information on ambulatory blood pressure (BP) at baseline and follow-up. Baseline blood samples were analysed for 22 inflammatory mediators using multiplexing technology. Principal component analysis was used to study associations between clusters of inflammatory mediators and ΔBP.

Results

In the total cohort in multivariable-adjusted regression analyses, percentage change in 24hr systolic BP associated positively with Factors 1 (Interferon-gamma, interleukin (IL)-4, IL-7, IL-10, IL-12, IL-17A, IL-21, IL-23, macrophage inflammatory protein (MIP)-1α, MIP-1β, TNF-α, granulocyte-macrophage colony-stimulating factor (GM-CSF)) and 2 (IL-5, IL-6, IL-8, IL-13). Change in daytime systolic BP associated positively with Factors 1, 2 and 3 (C-Reactive protein, IL-1β, IL-2, MIP-3α). Subgroup analysis found these findings were limited to white study participants. Numerous associations were present between individual inflammatory mediators (Interferon-gamma, GM-CSF, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17A, IL-21, IL-23, MIP-1α and MIP-1β) and ΔBP in the white but not black subgroups.

Conclusion

We found independent relationships between numerous inflammatory mediators (individual and clusters) and ΔBP over 4.5 years. The relationship between inflammatory markers and ΔBP was only found in white participants. ClinicalTrials.gov (Identifier: NCT03292094)..

Integrating systematic biological and proteomics strategies to explore the pharmacological mechanism of danshen yin modified on atherosclerosis

This research utilized the systematic biological and proteomics strategies to explore the regulatory mechanism of Danshen Yin Modified (DSYM) on atherosclerosis (AS) biological network. The traditional Chinese medicine database and HPLC was used to find the active compounds of DSYM, Pharmmapper database was used to predict potential targets, and OMIM database and GeneCards database were used to collect AS targets. String database was utilized to obtain the other protein of proteomics proteins and the protein-protein interaction (PPI) data of DSYM targets, AS genes, proteomics proteins and other proteins. The Cytoscape 3.7.1 software was utilized to construct and analyse the network. The DAVID database is used to discover the biological processes and signalling pathways that these proteins aggregate. Finally, animal experiments and proteomics analysis were used to further verify the prediction results. The results showed that 140 active compounds, 405 DSYM targets and 590 AS genes were obtained, and 51 differentially expressed proteins were identified in the DSYM-treated ApoE-/- mouse AS model. A total of 4 major networks and a number of their derivative networks were constructed and analysed. The prediction results showed that DSYM can regulate AS-related biological processes and signalling pathways. Animal experiments have also shown that DSYM has a therapeutic effect on ApoE-/-mouse AS model (P < .05). Therefore, this study proposed a new method based on systems biology, proteomics, and experimental pharmacology, and analysed the pharmacological mechanism of DSYM. DSYM may achieve therapeutic effects by regulating AS-related signalling pathways and biological processes found in this research.

Novel human immunomodulatory T cell receptors and their double-edged potential in autoimmunity, cardiovascular disease and cancer

In the last decade, approaches based on T cells and their immunomodulatory receptors have emerged as a solid improvement in treatments for various types of cancer. However, the roles of these molecules in the therapeutic context of autoimmune and cardiovascular diseases are still relatively unexplored. Here, we review the best known and most commonly used immunomodulatory T cell receptors in clinical practice (PD-1 and CTLA-4), along with the rest of the receptors with known functions in animal models, which have great potential as modulators in human pathologies in the medium term. Among these other receptors is the receptor CD69, which has recently been described to be expressed in mouse and human T cells in autoimmune and cardiovascular diseases and cancer. However, inhibition of these receptors individually or in combination by drugs or monoclonal antibodies generates a loss of immunological tolerance and can trigger multiple autoimmune disorders in different organs and immune-related adverse effects. In the coming decades, knowledge on the functions of different immunomodulatory receptors will be pivotal for the development of new and better therapies with less harmful side effects. In this review, we discuss the roles of these receptors in the control of immunity from a perspective focused on therapeutic potential in not only cancer but also autoimmune diseases, such as systemic lupus erythematosus, autoimmune diabetes and rheumatoid arthritis, and cardiovascular diseases, such as atherosclerosis, acute myocardial infarction, and myocarditis.

YKL-40 as a novel biomarker in cardio-metabolic disorders and inflammatory diseases

Dyslipidaemia is associated with numerous health problems that include the combination of insulin resistance, hypertension and obesity, ie, metabolic syndrome. Although the use of statins to decrease serum low density lipoprotein cholesterol (LDL-C) has been an effective therapeutic in treating atherosclerosis, the persistence of high atherosclerotic risk, ie, residual risk, is notable and is not simply explained as a phenomenon of dyslipidaemia. As such, it is imperative that we identify new biomarkers to monitor treatment and more accurately predict future cardiovascular events. This athero-protective strategy includes the assessment of novel inflammatory biomarkers such as YKL-40. Recent evidence has implicated YKL-40 in patients with inflammatory diseases and cardio-metabolic disorders, making it potentially useful to evaluate disease severity, prognosis and survival. In this review, we summarize role of YKL-40 in the pathogenesis of cardio-metabolic disorders and explore its use as a novel biomarker for monitoring athero-protective therapy.