Unravelling CD4+ T cell diversity and tissue adaptation of Tregs in abdominal aortic aneurysms through single-cell sequencing.

Immune cell infiltration is a significant pathological process in abdominal aortic aneurysms (AAA). T cells, particularly CD4+ T cells, are essential immune cells responsible for substantial infiltration of the aorta. Regulatory T cells (Tregs) in AAA have been identified as tissue-specific; however, the time, location, and mechanism of acquiring the tissue-specific phenotype are still unknown. Using single-cell RNA sequencing (scRNA-seq) on CD4+ T cells from the AAA aorta and spleen, we discovered heterogeneity among CD4+ T cells and identified activated, proliferating and developed aorta Tregs. These Tregs originate in the peripheral tissues and acquire the tissue-specific phenotype in the aorta. The identification of precursors for Tregs in AAA provides new insight into the pathogenesis of AAA.

A novel vaccine targeting ß1-adrenergic receptor.

Beta-blockers are widely used in the treatment of hypertension, heart failure and ischemic heart disease. However, unstandardized medication results in diverse clinical outcomes in patients. The main causes are unattained optimal doses, insufficient follow-up and patients' poor adherence. To improve the medication inadequacy, our team developed a novel therapeutic vaccine targeting ß1-adrenergic receptor (ß1-AR). The ß1-AR vaccine named ABRQß-006 was prepared by chemical conjugation of a screened ß1-AR peptide with Qß virus like particle (VLP). The antihypertensive, anti-remodeling and cardio-protective effects of ß1-AR vaccine were evaluated in different animal models. The ABRQß-006 vaccine was immunogenic that induced high titers of antibodies against ß1-AR epitope peptide. In the NG-nitro-L-arginine methyl ester (L-NAME) + Sprague Dawley (SD) hypertension model, ABRQß-006 lowered systolic blood pressure about 10 mmHg and attenuated vascular remodeling, myocardial hypertrophy and perivascular fibrosis. In the pressure-overload transverse aortic constriction (TAC) model, ABRQß-006 significantly improved cardiac function, decreased myocardial hypertrophy, perivascular fibrosis and vascular remodeling. In the myocardial infarction (MI) model, ABRQß-006 effectively improved cardiac remodeling, reduced cardiac fibrosis and inflammatory infiltration, which was superior to metoprolol. Moreover, no significant immune-mediated damage was observed in immunized animals. The ABRQß-006 vaccine targeting ß1-AR showed the effects on hypertension and heart rate control, myocardial remodeling inhibition and cardiac function protection. These effects could be differentiated in different types of diseases with diverse pathogenesis. ABRQß-006 could be a novel and promising method for the treatment of hypertension and heart failure with different etiologies.

Case report: Spontaneous closure of ventricular pseudoaneurysm post-acute myocardial infarction with non-surgical therapy.

Left ventricle (LV) pseudoaneurysm is a rare disorder post-acute myocardial infarction (AMI). Resection or closure of the pseudoaneurysm by surgery is recommended due to the high propensity of pseudoaneurysm rupture while surgery has also high risks. Conservative therapy could be acceptable in small pseudoaneurysms or patients with high surgical risks. Nevertheless, the risk evaluation and grasp of indication are not clear. This case reported an acute cyst-like LV pseudoaneurysm formation post-AMI-induced myocardial free wall rupture (MFWR), and the patient recovered with spontaneous closure of the fissure and shrinkage of the LV pseudoaneurysm through non-surgical therapy. Based on the observations in the echocardiogram, we proposed that intermittent closing of the fissure and interruption of the blood flow between the LV and the pseudoaneurysm due to LV contraction alleviated stress change on the pseudoaneurysm. The narrow fissure, small pseudoaneurysm, and intermittently interrupted blood flow that benefit fissure healing and pseudoaneurysm stabilization could indicate the prognosis of this patient. Drugs like ß-blocker that decreased the stress on the pseudoaneurysm also led to the risk reduction of pseudoaneurysm rupture. To our knowledge, this is the first case that reports a spontaneous closure of LV pseudoaneurysm. The size of the fissure and the pseudoaneurysm, as well as the corresponding hemodynamic state, could be valuable to evaluate the risk and prognosis of the pseudoaneurysm. Optimized medical management was also helpful to pseudoaneurysm stabilization.

Case Report: Glucocorticoid Effect Observation in a Ureteral Urothelial Cancer Patient With ICI-Associated Myocarditis and Multiple Organ Injuries.

Immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAEs) are becoming important safety issues worthy of attention despite the exciting therapeutic prospects. The growing development of new ICIs also brings new cases of irAEs, raising more challenges to clinicians. Cardiac injury is rare but life-threatening among diverse organ injuries, and effective interventions are critical for patients. Here, we report a novel programmed cell death protein-1 (PD-1) inhibitor tislelizumab-associated severe myocarditis and myositis accompanied by liver and kidney damage in a ureteral urothelial cancer patient, who was firstly treated by cardiologists because of cardiac symptoms. Due to the lack of experience about ICI-associated irAEs, an initial low-dose (0.5 mg/kg/day) and short-term methylprednisolone therapy was used and found to be ineffective and risky to the patient; then, steroid therapy was modulated to a higher dose (1.5 mg/kg/day) with prolonged time course, and improvement of patient symptoms and laboratory markers were observed quickly and persistently. The patient did not show adverse events under this steroid dosage. This case reports a rare tislelizumab-related myocarditis and multiple organ injuries, which provides valuable experience to cardiologists like us. Early recognition of ICI-associated myocarditis and sufficient dosage and time course of glucocorticoid therapy are critical for severe cases. High-quality clinical evidence about the precise diagnosis and therapy in ICI-associated myocarditis and other organ injuries are necessary to guide our clinical works.

Artemisinin-Ginkgo biloba extract combination therapy for Plasmodium yoelii.

Malaria remains a widespread life-threatening infectious disease, leading to an estimated 219 million cases and around 435,000 deaths. After an unprecedented success, the antimalarial progress is at a standstill. Therefore, new methods are urgently needed to decrease drug resistant and enhance antimalarial efficacy. According to the alteration of erythrocyte biomechanical properties and the immune evasion mechanism of parasites, drugs, which can improve blood circulation, can be chosen to combine with antimalarial drugs for malaria treatment. Ginkgo biloba extract (GBE), one of drug for vascular disease, was used to combine with artemisinin for Plasmodium yoelii therapy. Artemisinin-GBE combination therapy (AGCT) demonstrated remarkable antimalarial efficacy by decreasing infection rate, improving blood microcirculation and modulating immune system. Besides, the expression of invasion related genes, such as AMA1, MSP1 and Py01365, can be suppressed by AGCT, hindering invasion process of merozoites. This new antimalarial strategy, combining antimalarial drugs with drugs that improve blood circulation, may enhance the antimalarial efficacy and ameliorate restoration ability, proving a potential method for finding ideal compatible drugs to improve malaria therapy.

A bivalent antihypertensive vaccine targeting L-type calcium channels and angiotensin AT1 receptors.

BACKGROUND AND PURPOSE: Hypertension has been the leading preventable cause of premature death worldwide. The aim of this study was to design a more efficient vaccine against novel targets for the treatment of hypertension. EXPERIMENTAL APPROACH: The epitope CE12, derived from the human L-type calcium channel (CaV 1.2), was designed and conjugated with Qß bacteriophage virus-like particles to test the efficacy in hypertensive animals. Further, the hepatitis B core antigen (HBcAg)-CE12-CQ10 vaccine, a bivalent vaccine based on HBcAg virus-like particles and targeting both human angiotensin AT1 receptors and CaV 1.2 channels, was developed and evaluated in hypertensive rodents. KEY RESULTS: The Qß-CE12 vaccine effectively decreased the BP in hypertensive rodents. A monoclonal antibody against CE12 specifically bound to L-type calcium channels and inhibited channel activity. Injection with monoclonal antibody against CE12 effectively reduced the BP in angiotensin II-induced hypertensive mice. The HBcAg-CE12-CQ10 vaccine showed antihypertensive effects in hypertensive mice and relatively superior antihypertensive effects in spontaneously hypertensive rats and ameliorated L-NAME-induced renal injury. In addition, no obvious immune-mediated damage or electrophysiological adverse effects were detected. CONCLUSION AND IMPLICATIONS: Immunotherapy against both AT1 receptors and CaV 1.2 channels decreased the BP in hypertensive rodents effectively and provided protection against hypertensive target organ damage without obvious feedback activation of renin-angiotensin system or induction of dominant antibodies against the carrier protein. Thus, the HBcAg-CE12-CQ10 vaccine may provide a novel and promising therapeutic approach for hypertension.

Immunotherapy of Endothelin-1 Receptor Type A for Pulmonary Arterial Hypertension.

BACKGROUND: Pulmonary arterial hypertension (PAH) is a chronic fatal disease. The treatment of PAH is less than ideal and the control is far from satisfactory worldwide. Vaccination provides a promising approach for treatment of PAH. OBJECTIVES: This study sought to find a vaccine against endothelin-1 (ET-1) receptor type A (ETAR) for treating PAH. METHODS: The ETRQß-002 vaccine was screened and the specific antibodies against epitope ETR-002 belonging to the second extracellular loop of ETAR (including the polyclonal and monoclonal antibody) were produced. The effect of the antibodies on Ca2+-dependent signal transduction events was investigated. In vivo, ETRQß-002 vaccine was used to vaccinate monocrotaline (MCT)- and Sugen/hypoxia-induced pulmonary hypertension animals. The monoclonal antibody (mAb) against ETR-002 was also injected into the PAH animals. The effect of ETRQß-002 vaccine on pulmonary hypertension and remodeling of pulmonary arterioles and right ventricle (RV) was carefully evaluated. Further, the possible immune-mediated damage was detected in normal vaccinated animals. RESULTS: ETR-002 peptide has perfect immunogenicity and ETRQß-002 vaccine could induce strong antibody production. In vitro, the anti-ETR-002 antibody bound to ETAR and inhibited Ca2+-dependent signal transduction events, including extracellular signal-regulated kinase phosphorylation and elevation of intracellular Ca2+ concentration induced by ET-1. In vivo, both ETRQß-002 vaccine and the mAb significantly decreased the RV systolic pressure up to 20 mm Hg and 10 mm Hg in MCT-exposed rats and Sugen/hypoxia-exposed mice, respectively. Also, ETRQß-002 vaccine/mAb obviously ameliorated pathological remodeling of pulmonary arterioles and hypertrophy of the RV in PAH animals. Additionally, no significant immune-mediated damage was detected in vaccinated animals. CONCLUSIONS: ETRQß-002 vaccine/mAb attenuated remodeling of pulmonary arterioles and RV in MCT- and Sugen/hypoxia-induced PAH animals and decreased RV systolic pressure effectively through diminishing the pressure response and inhibiting signal transduction initiated by ET-1. ETRQß-002 vaccine/mAb may provide a novel and promising method for PAH treatment.

A Therapeutic Peptide Vaccine Against PCSK9.

Vaccination provides a promising approach for treatment of hypercholesterolemia and improvement in compliance. In this study, the appropriate virus-like particle (VLP)-peptide vaccines targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) were screened. The screening criteria of target peptides were as follows: (1) located in catalytic domain of PCSK9, or regulating the binding of PCSK9 and LDL receptors (LDLR); (2) having low/no-similarity when matched with the host proteome; (3) possessing ideal antigenicity and hydrophilicity; (4) including the functional mutation site of PCSK9. It was found that mice vaccinated with VLP -PCSK9 peptide vaccines, especially PCSK9Qß-003 vaccine, developed high titer IgG antibodies against PCSK9. PCSK9Qß-003 vaccine obviously decreased plasma total cholesterol in both Balb/c mice and LDLR+/- mice. Also, PCSK9Qß-003 vaccine decreased plasma PCSK9 level and up-regulated LDLR expression in liver. Additionally, PCSK9Qß-003 vaccine injection was associated with significant up-regulation of sterol-regulatory element-binding protein-2 (SREBP-2), hepatocyte nuclear factor 1α (HNF-1α), and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in LDLR+/- mice. No obvious immune injury was detected in vaccinated animals. The PCSK9Qß-003 vaccine, therefore, may be an attractive treatment approach for hypercholesterolemia through decreasing cholesterol and regulating lipid homeostasis.

Immune Response of A Novel ATR-AP205-001 Conjugate Anti-hypertensive Vaccine.

We developed a virus-like particle (VLP)-based therapeutic vaccine against angiotensin II receptor type 1, ATR-AP205-001, which could significantly reduce the blood pressure and protect target organs of hypertensive animals. In this study, we focused on the immunological effect and safety of the VLP-based vaccine. By comparing to the depolymerized dimeric vaccine ATR-Dimer-001, we found that ATR-AP205-001 reached subcapsular sinus of lymph node shortly after administration, followed by accumulation on follicle dendritic cells via follicle B cell transportation, while ATR-Dimer-001 vaccine showed no association with FDCs. ATR-AP205-001 vaccine strongly activated dendritic cells, which promoted T cells differentiation to follicular helper T cells. ATR-AP205-001 vaccine induced powerful germinal center reaction, which was translated to a boost of specific antibody production and long-lasting B cell memory, far superior to ATR-Dimer-001 vaccine. Moreover, neither cytotoxic T cells, nor Th1/Th17 cell-mediated inflammation was observed in ATR-AP205-001 vaccine, similar to ATR-Dimer-001 vaccine. We concluded that ATR-AP205-001 vaccine quickly induced potent humoral immunity through collaboration of B cells, follicular dendritic cells and follicular helper T cells, providing an effective and safe intervention for hypertension in the future clinical application.

Effects of vagus nerve stimulation on cognitive functioning in rats with cerebral ischemia reperfusion.

BACKGROUND: Vagus nerve stimulation (VNS) has become the most common non-pharmacological treatment for intractable drug-resistant epilepsy. However, the contribution of VNS to neurological rehabilitation following stroke has not been thoroughly examined. Therefore, we investigated the specific role of acute VNS in the recovery of cognitive functioning and the possible mechanisms involved using a cerebral ischemia/reperfusion (I/R) injury model in rats. METHODS: The I/R-related injury was modeled using occlusion and reperfusion of the middle cerebral artery (MCAO/R) in Sprague-Dawley rats. VNS was concurrently applied to the vagus nerve using a stimulation intensity of 1 mA at a fixed frequency of 20 Hz with a 0.4-ms bipolar pulse width. The stimulation duration and inter-train interval were both 3 s. Next, Morris water maze and shuttle-box behavioral experiments were conducted to assess the effects of VNS on the recovery of learning, memory, and inhibitory avoidance following I/R injury. Intracerebroventricular injection of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP-4), a selective neurotoxin for noradrenergic neurons, was used to evaluate the role of norepinephrine (NE) as a mediator of therapeutic effects of VNS on cognitive recovery. RESULTS: Compared with the MCAO/R group, the VNS+MCAO/R group had improved spatial memory as indicated by swimming path lengths and escape latencies in the Morris water maze, and fear memory, as indicated by the avoidance conditioned response rate, mean shock duration, and avoidance time in shuttle-box behavior experiments. Compared with the VNS+MCAO/R group, the DSP-4+VNS+MCAO/R group, which had reduced NE levels in cortical and hippocampal brain regions, showed a reversal of the VNS-induced benefits on spatial and fear memory performance. CONCLUSIONS: VNS improves spatial and fear memory in a rat model of MCAO/R injury. However, a reduction in NE from the administration of DSP-4 blocks these protective effects, suggesting that NE may contribute to the influence exhibited by VNS on memory performance in rats with cerebral I/R-related injury.

ATRQß-001 vaccine prevents atherosclerosis in apolipoprotein E-null mice.

OBJECTIVE: Angiotensin II (AngII) type 1 receptor (AT1R) blockers have been proved to reduce atherosclerosis. Previously, we have invented ATRQß-001 vaccine which showed a desirable blocking effect for AT1R. The purpose of this study was to investigate whether ATRQß-001 vaccine would prevent atherosclerosis in apolipoprotein E-null (ApoE-/-) mice. METHODS: Male ApoE-/- mice were administered with ATRQß-001 vaccine, Qß virus-like particles, valsartan or vehicle over a period of 24 weeks. In vitro, human coronary artery endothelial cells preincubated with the anti-ATR-001 antibody, the neutralization antibody or valsartan for 2  h, were treated with AngII for 24  h. Histological stain and molecule biology methods were used to assess the atheroprotective effect of the vaccine. RESULTS: ATRQß-001 vaccine significantly reduced the lesion area and promoted the stability of atherosclerotic plaque. Meanwhile, macrophage infiltration as well as the expressions of adhesion molecules and monocyte chemoattractant protein-1 was obviously decreased in the ATRQß-001 vaccine group. Additionally, the vaccine markedly reduced the apoptosis in the lesions of the ApoE-/- mice. In vitro, the anti-ATR-001 antibody inhibited endothelial apoptosis induced by AngII. Furthermore, ATRQß-001 vaccine exhibited a dramatical attenuation in the expressions of lectin-like oxidized low-density lipoprotein receptor-1 and AT1R in the aortic. More importantly, compared with the valsartan group, no obvious feedback of the plasma renin-angiotensin system was elicited in the vaccine group. CONCLUSION: The results demonstrated that ATRQß-001 vaccine reduced the progression of atherosclerosis in ApoE-/- mice without obvious feedback of renin-angiotensin system.

Vaccination against type 1 angiotensin receptor prevents streptozotocin-induced diabetic nephropathy.

UNLABELLED: Recently, our group has developed a therapeutic hypertensive vaccine against angiotensin (Ang) II type 1 receptor (AT1R) named ATRQß-001. To explore its potential effectiveness on streptozotocin-induced diabetic nephropathy, male Sprague Dawley rats were randomly divided into two groups: a control and a diabetic model. After 1 week, the diabetic rats were divided into four subgroups (each with 15 rats) for 14-week treatments with saline, olmesartan, ATRQß-001, and Qß virus-like particle (VLP), respectively. In addition to lower blood pressure, ATRQß-001 vaccination ameliorated biochemical parameter changes of renal dysfunction, mesangial expansion, and fibrosis through inhibiting oxidative stress, macrophage infiltration, and proinflammatory factor expression. Furthermore, ATRQß-001 vaccination suppressed renal Ang II-AT1R activation and abrogated the downregulation of angiotensin-converting enzyme 2-Ang (1-7), similar to olmesartan treatment, while no obvious feedback activation of circulating or local renin-angiotensin system (RAS) was only observed in vaccine group. In rat mesangial cells, the anti-ATR-001 antibody inhibited high glucose-induced transforming growth factor-ß1 (TGF)-ß1/Smad3 signal pathway. Additionally, no significant immune-mediated damage was detected in vaccinated animals. In conclusion, the ATRQß-001 vaccine ameliorated streptozotocin-induced diabetic renal injury via modulating two RAS axes and inhibiting TGF-ß1/Smad3 signal pathway, providing a novel, safe, and promising method to treat diabetic nephropathy. KEY MESSAGES: Overactivation of RAS plays a crucial role in the development of the DN. Our aim was to verify the effectiveness of ATRQß-001 vaccine in STZ-induced DN. The ATRQß-001 modulated two RAS axes and inhibited TGF-ß1/Smad3 signal pathway. The vaccine therapy may provide a novel, safe, and promising method to treat DN.