Targeting IDH2R140Q and other neoantigens in acute myeloid leukemia

ABSTRACT

For patients with high-risk or relapsed/refractory acute myeloid leukemia (AML), allogeneic stem cell transplantation (allo-HSCT) and the graft-versus-leukemia effect mediated by donor T cells, offer the best chance of long-term remission. However, the concurrent transfer of alloreactive T cells can lead to graft-versus-host disease that is associated with transplant-related morbidity and mortality. Furthermore, ∼60% of patients will ultimately relapse after allo-HSCT, thus, underscoring the need for novel therapeutic strategies that are safe and effective. In this study, we explored the feasibility of immunotherapeutically targeting neoantigens, which arise from recurrent nonsynonymous mutations in AML and thus represent attractive targets because they are exclusively present on the tumor. Focusing on 14 recurrent driver mutations across 8 genes found in AML, we investigated their immunogenicity in 23 individuals with diverse HLA profiles. We demonstrate the immunogenicity of AML neoantigens, with 17 of 23 (74%) reactive donors screened mounting a response. The most immunodominant neoantigens were IDH2R140Q (n = 11 of 17 responders), IDH1R132H (n = 7 of 17), and FLT3D835Y (n = 6 of 17). In-depth studies of IDH2R140Q-specific T cells revealed the presence of reactive CD4+ and CD8+ T cells capable of recognizing distinct mutant-specific epitopes restricted to different HLA alleles. These neo-T cells could selectively recognize and kill HLA-matched AML targets endogenously expressing IDH2R140Q both in vitro and in vivo. Overall, our findings support the clinical translation of neoantigen-specific T cells to treat relapsed/refractory AML.

Human platelet lysate enhances in vivo activity of CAR-Vδ2 T cells by reducing cellular senescence and apoptosis

BACKGROUND AIMS

Vγ9Vδ2 T cells are an attractive cell platform for the off-the-shelf cancer immunotherapy as the result of their lack of alloreactivity and inherent multi-pronged cytotoxicity, which could be further amplified with chimeric antigen receptors (CARs). In this study, we sought to enhance the in vivo longevity of CAR-Vδ2 T cells by modulating ex vivo manufacturing conditions and selecting an optimal CAR costimulatory domain.

METHODS

Specifically, we compared the anti-tumor activity of Vδ2 T cells expressing anti-CD19 CARs with costimulatory endodomains derived from CD28, 4-1BB or CD27 and generated in either standard fetal bovine serum (FBS)- or human platelet lysate (HPL)-supplemented medium.

RESULTS

We found that HPL supported greater expansion of CAR-Vδ2 T cells with comparable in vitro cytotoxicity and cytokine secretion to FBS-expanded CAR-Vδ2 T cells. HPL-expanded CAR-Vδ2 T cells showed enhanced in vivo anti-tumor activity with longer T-cell persistence compared with FBS counterparts, with 4-1BB costimulated CAR showing the greatest activity. Mechanistically, HPL-expanded CAR Vδ2 T cells exhibited reduced apoptosis and senescence transcriptional pathways compared to FBS-expanded CAR-Vδ2 T cells and increased telomerase activity.

CONCLUSIONS

This study supports enhancement of therapeutic potency of CAR-Vδ2 T cells through a manufacturing improvement.

A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

Engineering T cells to suppress acute GVHD and leukemia relapse after allogeneic hematopoietic stem cell transplantation

Acute graft-versus-host disease (aGVHD) limits the therapeutic benefit of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and requires immunosuppressive prophylaxis that compromises antitumor and antipathogen immunity. OX40 is a costimulatory receptor upregulated on circulating T cells in aGVHD and plays a central role in driving the expansion of alloreactive T cells. Here, we show that OX40 is also upregulated on T cells infiltrating GVHD target organs in a rhesus macaque model, supporting the hypothesis that targeted ablation of OX40+ T cells will mitigate GVHD pathogenesis. We thus created an OX40-specific cytotoxic receptor that, when expressed on human T cells, enables selective elimination of OX40+ T cells. Because OX40 is primarily upregulated on CD4+ T cells upon activation, engineered OX40-specific T cells mediated potent cytotoxicity against activated CD4+ T cells and suppressed alloreactive T-cell expansion in a mixed lymphocyte reaction model. OX40 targeting did not inhibit antiviral activity of memory T cells specific to Epstein-Barr virus, cytomegalovirus, and adenoviral antigens. Systemic administration of OX40-targeting T cells fully protected mice from fatal xenogeneic GVHD mediated by human peripheral blood mononuclear cells. Furthermore, combining OX40 targeting with a leukemia-specific chimeric antigen receptor in a single T cell product provides simultaneous protection against leukemia and aGVHD in a mouse xenograft model of residual disease posttransplant. These results underscore the central role of OX40+ T cells in mediating aGVHD pathogenesis and support the feasibility of a bifunctional engineered T-cell product derived from the stem cell donor to suppress both disease relapse and aGVHD following allo-HSCT.

Novel banana lectin CAR-T cells to target pancreatic tumors and tumor-associated stroma

BACKGROUND

Cell therapies for solid tumors are thwarted by the hostile tumor microenvironment (TME) and by heterogeneous expression of tumor target antigens. We address both limitations with a novel class of chimeric antigen receptors based on plant lectins, which recognize the aberrant sugar residues that are a 'hallmark' of both malignant and associated stromal cells. We have expressed in T cells a modified lectin from banana, H84T BanLec, attached to a chimeric antigen receptor (H84T-CAR) that recognizes high-mannose (asparagine residue with five to nine mannoses). Here, we tested the efficacy of our novel H84T CAR in models of pancreatic ductal adenocarcinoma (PDAC), intractable tumors with aberrant glycosylation and characterized by desmoplastic stroma largely contributed by pancreatic stellate cells (PSCs).

METHODS

We transduced human T cells with a second-generation retroviral construct expressing the H84T BanLec chimeric receptor, measured T-cell expansion, characterized T-cell phenotype, and tested their efficacy against PDAC tumor cells lines by flow cytometry quantification. In three-dimensional (3D) spheroid models, we measured H84T CAR T-cell disruption of PSC architecture, and T-cell infiltration by live imaging. We tested the activity of H84T CAR T cells against tumor xenografts derived from three PDAC cell lines. Antitumor activity was quantified by caliper measurement and bioluminescence signal and used anti-human vimentin to measure residual PSCs.

RESULTS

H84T BanLec CAR was successfully transduced and expressed by T cells which had robust expansion and retained central memory phenotype in both CD4 and CD8 compartments. H84T CAR T cells targeted and eliminated PDAC tumor cell lines. They also disrupted PSC architecture in 3D models in vitro and reduced total tumor and stroma cells in mixed co-cultures. H84T CAR T cells exhibited improved T-cell infiltration in multicellular spheroids and had potent antitumor effects in the xenograft models. We observed no adverse effects against normal tissues.

CONCLUSIONS

T cells expressing H84T CAR target malignant cells and their stroma in PDAC tumor models. The incorporation of glycan-targeting lectins within CARs thus extends their activity to include both malignant cells and their supporting stromal cells, disrupting the TME that otherwise diminishes the activity of cellular therapies against solid tumors.

Feasibility and preclinical efficacy of CD7-unedited CD7 CAR T cells for T cell malignancies

Chimeric antigen receptor (CAR)-mediated targeting of T lineage antigens for the therapy of blood malignancies is frequently complicated by self-targeting of CAR T cells or their excessive differentiation driven by constant CAR signaling. Expression of CARs targeting CD7, a pan-T cell antigen highly expressed in T cell malignancies and some myeloid leukemias, produces robust fratricide and often requires additional mitigation strategies, such as CD7 gene editing. In this study, we show fratricide of CD7 CAR T cells can be fully prevented using ibrutinib and dasatinib, the pharmacologic inhibitors of key CAR/CD3ζ signaling kinases. Supplementation with ibrutinib and dasatinib rescued the ex vivo expansion of unedited CD7 CAR T cells and allowed regaining full CAR-mediated cytotoxicity in vitro and in vivo on withdrawal of the inhibitors. The unedited CD7 CAR T cells persisted long term and mediated sustained anti-leukemic activity in two mouse xenograft models of human T cell acute lymphoblastic leukemia (T-ALL) by self-selecting for CD7-, fratricide-resistant CD7 CAR T cells that were transcriptionally similar to control CD7-edited CD7 CAR T cells. Finally, we showed feasibility of cGMP manufacturing of unedited autologous CD7 CAR T cells for patients with CD7+ malignancies and initiated a phase I clinical trial (ClinicalTrials.gov: NCT03690011) using this approach. These results indicate pharmacologic inhibition of CAR signaling enables generating functional CD7 CAR T cells without additional engineering.

A Case of Foldable Artificial Iris Implantation for Treatment of Postcataract Surgery Aniridia

We report an approach for managing acquired aniridia induced by intraoperative floppy iris syndrome (IFIS) during cataract surgery. An 81-year-old man with right blurred vision and photophobia symptoms was treated for extensive iris defects due to cataract surgery aniridia. The retained iris for the patient was observed at the 5-10 o'clock position, with the intraocular lens (IOL) inside the capsular bag. Although the aniridia symptoms were successfully addressed by the implantation of a foldable artificial iris (Iris Prosthesis: Ophtec [formerly Reper], Groningen, the Netherlands), the procedure subsequently caused endothelial damage. In summary, while the utilization of the foldable artificial iris can improve aniridia symptoms, further advances in the insertion technique are required.

Levetiracetam poisoning with acute kidney injury treated with hemodialysis: A case report

INTRODUCTION

Levetiracetam is a newer second-generation anticonvulsant for the treatment of generalized and partial seizure disorders. Common adverse effects are rhabdomyolysis and neuropsychiatric problems, such as somnolence, dizziness, and mood changes. The present report describes the first case, to our knowledge, of levetiracetam overdose resulting in acute kidney injury for which hemodialysis was required.

PATIENT CONCERNS

A 51-year-old man presented with hypotension and disturbance of consciousness with subsequent development of oliguria and elevated creatinine. Based on his history of ingesting a large dose of levetiracetam and the course of the disease, he was considered to have been poisoned by levetiracetam.

DIAGNOSIS

Acute kidney injury induced by levetiracetam poisoning.

INTERVENTIONS/OUTCOMES

Dialysis was performed for the rapidly progressing renal failure. His renal function improved, and he was weaned from dialysis and discharged home on the 19th day.

CONCLUSION

We should be aware of the possibility that severe renal function deterioration may occur in some patients with levetiracetam overdose. It is possible that clinicians underestimate the occurrence of this problem. In cases of acute renal failure in levetiracetam poisoning, induction of dialysis is beneficial.

Engineering T cells to prevent graft-versus-host disease and leukemia relapse following allogeneic stem cell transplantation

Acute graft-versus-host disease (aGvHD) and leukemia relapse remain major causes of mortality after allogeneic hematopoietic stem cell transplantation (alloHSCT). Prophylaxis and treatment of aGvHD rely on generalized immunosuppression, increasing the risk of tumor relapse and opportunistic infections and emphasizing the need for more targeted therapies.

Alloreactive donor CD4+ T cells play a central role in aGvHD pathogenesis, we thus hypothesized that elimination of activated CD4+ T cells with engineered T cells would mitigate aGvHD while preserving protective CD8+ T cell immunity post alloHSCT. We developed an alloimmune defense receptor (ADR) targeting OX40, a surface marker predominantly upregulated on activated CD4+ T cells. OX40 ADR-expressing T cells eliminated activated CD4+ T cells during coculture but spared the majority of activated CD8+ T cells, including virus-specific T cells, and had no discernible activity against resting lymphocytes. A single infusion of ADR T cells fully protected mice from fatal xenogeneic aGvHD induced by intravenous injection of human PBMC, minimizing signs of aGvHD and maximizing survival. To enable simultaneous activity of engineered T cells against aGvHD and leukemia relapse, we further armed ADR T cells with a CD19-directed chimeric antigen receptor (CAR). In a mouse model of residual leukemia post alloHSCT, administration of T cells co-expressing OX40 ADR and CD19 CAR mediated dual protection against tumor relapse and aGvHD. These results support the feasibility of a bi-functional CAR.ADR T cell product to improve outcomes post alloHSCT and reduce transplant-related mortality.

Supported by grant from Leukemia & Lymphoma Society.

Impact of Manufacturing Procedures on CAR T Cell Functionality

The field of chimeric antigen receptor (CAR) modified T cell therapy has rapidly expanded in the past few decades. As of today, there are six CAR T cell products that have been approved by the FDA: KYMRIAH (tisagenlecleucel, CD19 CAR T cells), YESCARTA (axicabtagene ciloleucel, CD19 CAR T cells), TECARTUS (brexucabtagene autoleucel, CD19 CAR T cells), BREYANZI (lisocabtagene maraleucel, CD19 CAR T cells), ABECMA (idecabtagene vicleucel, BCMA CAR T cells) and CARVYKTI (ciltacabtagene autoleucel, BCMA CAR T cells). With this clinical success, CAR T cell therapy has become one of the most promising treatment options to combat cancers. Current research efforts focus on further potentiating its efficacy in non-responding patients and solid tumor settings. To achieve this, recent evidence suggested that, apart from developing next-generation CAR T cells with additional genetic modifications, ex vivo culture conditions could significantly impact CAR T cell functionality – an often overlooked aspect during clinical translation. In this review, we focus on the ex vivo manufacturing process for CAR T cells and discuss how it impacts CAR T cell function.

Selectively targeting myeloid-derived suppressor cells through TRAIL receptor 2 to enhance the efficacy of CAR T cell therapy for treatment of breast cancer

BACKGROUND

Successful targeting of solid tumors such as breast cancer (BC) using chimeric antigen receptor (CAR) T cells has proven challenging, largely attributed to the immunosuppressive tumor microenvironment (TME). Myeloid-derived suppressor cells (MDSCs) inhibit CAR T cell function and persistence within the breast TME. To overcome this challenge, we have developed CAR T cells targeting tumor-associated mucin 1 (MUC1) with a novel chimeric costimulatory receptor that targets tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TR2) expressed on MDSCs.

METHODS

The function of the TR2.41BB costimulatory receptor was assessed by exposing non-transduced (NT) and TR2.41BB transduced T cells to recombinant TR2, after which nuclear translocation of NFκB was measured by ELISA and western blot. The cytolytic activity of CAR.MUC1/TR2.41BB T cells was measured in a 5-hour cytotoxicity assay using MUC1+ tumor cells as targets in the presence or absence of MDSCs. In vivo antitumor activity was assessed using MDSC-enriched tumor-bearing mice treated with CAR T cells with or without TR2.41BB.

RESULTS

Nuclear translocation of NFκB in response to recombinant TR2 was detected only in TR2.41BB T cells. The presence of MDSCs diminished the cytotoxic potential of CAR.MUC1 T cells against MUC1+ BC cell lines by 25%. However, TR2.41BB expression on CAR.MUC1 T cells induced MDSC apoptosis, thereby restoring the cytotoxic activity of CAR.MUC1 T cells against MUC1+ BC lines. The presence of MDSCs resulted in an approximately twofold increase in tumor growth due to enhanced angiogenesis and fibroblast accumulation compared with mice with tumor alone. Treatment of these MDSC-enriched tumors with CAR.MUC1.TR2.41BB T cells led to superior tumor cell killing and significant reduction in tumor growth (24.54±8.55 mm³) compared with CAR.MUC1 (469.79±81.46 mm³) or TR2.41BB (434.86±64.25 mm³) T cells alone. CAR.MUC1.TR2.41BB T cells also demonstrated improved T cell proliferation and persistence at the tumor site, thereby preventing metastases. We observed similar results using CAR.HER2.TR2.41BB T cells in a HER2+ BC model.

CONCLUSIONS

Our findings demonstrate that CAR T cells that coexpress the TR2.4-1BB receptor exhibit superior antitumor potential against breast tumors containing immunosuppressive and tumor promoting MDSCs, resulting in TME remodeling and improved T cell proliferation at the tumor site.

The effectiveness of strict low-density lipoprotein cholesterol management in secondary prevention of Japanese patients

Background

In Japanese guidelines, target value of low-density lipoprotein cholesterol (LDL-C) <100mg/dL is recommended as standard management for secondary prevention of coronary artery disease. On the other hand, the guidelines also state that LDL-C targeting <70mg/dL should be considered in high-risk patients. However, the effectiveness of strict LDL-C management in the prevention of long-term coronary event recurrence in Japanese patients remains unclear.

Purpose

The purpose of the present study was to evaluate whether the strict management of LDL-C targeting <70 mg/dL was effective to prevent recurrence of acute coronary syndrome (ACS) than standard management in patients with previous percutaneous coronary intervention (PCI).

Methods

From January 2007 to August 2020, we performed coronary angiography in 359 patients with previous PCI who were suspected of having signs of recurrent cardiac ischemia. Patients were stratified into three groups according to achieved LDL-C value; <70mg/dL (n=57), 70 to <100mg/dL (n=135) and ≥100mg/dL (n=167). In addition, patients who had previous ACS and/or diabetes mellitus were defined as high-risk group, and sub-analysis by their achieved LDL-C values was performed in high-risk group and non-high-risk group. Endpoint was recurrence of ACS. Moreover, risk factors associated with recurrent-ACS were examined in patients with LDL-C <100 mg/dL.

Results

After follow-up (median 6.1 years), 99 patients (28%) had recurrent-ACS. Recurrent-ACS was significantly lower in patients with LDL-C <70mg/dL than LDL-C 70 to <100mg/dL and LDL-C ≥100mg/dL (p<0.01 and p<0.001, respectively). In sub-analysis, high-risk group with LDL-C <70 mg/dL had lower incidence of recurrent-ACS than LDL-C 70 to <100 mg/dL (p=0.03). Similar tendency was found in non-high-risk group (p=0.08). There was no difference of recurrent-ACS between high-risk group and non-high-risk group in patients with LDL-C <70mg/dL (p=0.41). Moreover, in patients with achieved LDL-C <100mg/dL (n=192), multivariate analysis identified that LDL-C (HR: 1.032, p<0.01) and HbA1c (HR: 1.330, p<0.01) were independent predictors of recurrent-ACS. In these patients, whether or not they were in the high-risk group was not a significant predictor (p=0.61).

Conclusions

Strict management of LDL-C targeting <70 mg/dL should be considered for a wider range of Japanese patients as well as for Westerners to prevent recurrence of ACS in secondary prevention.

Funding Acknowledgement

Type of funding sources: None. Probability of freedom from ACS

Overcoming the breast tumor microenvironment by targeting MDSCs through CAR-T cell therapy

1032

Background: Successful targeting of solid tumors such as breast cancer (BC) using CAR T cells (CARTs) has proven challenging, largely due to the immune suppressive tumor microenvironment (TME). Myeloid derived suppressor cells (MDSCs) inhibit CART’s function and persistence within the breast TME. We generated CAR T cells targeting tumor-expressed mucin 1 (MUC1) (Bajgain P et al, 2018) for BC. To potentiate expansion and persistence of MUC1 CARTs and modulate the suppressive TME, we developed a novel chimeric co-stimulatory receptor, TR2.4-1BB, encoding a ScFv derived from a TNF-related apoptosis-inducing ligand receptor 2 (TR2) mAb followed by a 4-1BB endodomain. We hypothesize that engagement with TR2 expressed on TME-resident MDSCs, will lead to both MDSC apoptosis and CART co-stimulation, promoting T cell persistence and expansion at tumor site. Methods: Function of the novel TR2.4-1BB receptor, was assessed by exposing non-transduced (NT) and TR2.4-1BB transduced T cells to recombinant TR2 and nuclear translocation of NFκB was measured by ELISA. Functionality of in vitro generated MDSCs was determined by the suppression assay. In vitro CART/costimulatory receptor T cell function was measured by cytotoxicity assays using MUC1+ tumor targets in presence or absence of MDSCs. In vivo anti-tumor activity was assessed using MDSC enriched tumor-bearing mice using calipers to assess tumor volume and bioluminescence imaging to track T cells. Results: Nuclear translocation of NFκB was detected only in TR2.4-1BB T cells. MDSCs significantly attenuated T cell proliferation by 50±5% and IFNγ production by half compared with T cells cultured alone. Additionally, presence of MDSCs, diminished cytotoxic potential of MUC1 CARTs against MUC1+ BC cell lines by 25%. However, TR2.4-1BB expression on CAR.MUC1 T cells induced MDSC apoptosis thereby restoring the cytotoxic activity of CAR.MUC1 against MUC1+ BC lines in presence of TR2.4-1BB (67±8.5%). There was an approximate two-fold increase in tumor growth due enhanced angiogenesis and fibroblast accumulation in mice receiving tumors + MDSCs compared to tumors alone. Treatment of these MDSC-enriched tumors with MUC1.TR2.4-1BB CARTs led to superior tumor cell killing and significant reduction in tumor growth (24.54±8.55 mm3) compared to CAR.MUC1 (469.79.9±81.46mm3) or TR2.4-1BB (434.86±64.25 mm3) T cells alone (Day 28 after T cell injection). The treatment also improved T cell proliferation and persistence at the tumor site. Thereby, leading to negligible metastasis demonstrating ability of CARTs to eliminate tumor and prevent dissemination. We observed similar results using HER2.TR2.4-1BB CARTs in a HER2+ BC model. Conclusions: Our findings demonstrate that CARTs co-expressing our novel TR2.4-1BB receptor have higher anti-tumor potential against BC tumors and infiltrating MDSCs, resulting in TME remodeling and improved T cell proliferation at the tumor site.

Off-the-Shelf Chimeric Antigen Receptor T Cells: How Do We Get There?

ABSTRACT

Banked chimeric antigen receptor (CAR) T cells immediately available for off-the-shelf (OTS) application can solve key limitations of patient-specific CAR T-cell products while retaining their potency. The allogeneic nature of OTS cell therapies requires additional measures to minimize graft-versus-host disease and host-versus-graft immune rejection in immunocompetent recipients. In this review, we discuss engineering and manufacturing strategies aimed at minimizing unwanted interactions between allogeneic CAR T cells and the host. Overcoming these limitations will improve safety and antitumor potency of OTS CAR T cells and facilitate their wider use in cancer therapy.

Long-year follow-up of acute myocardial infarction with preserved initial LVEF: prognostic impact of progressively reduced LVEF

Background

Severely reduced left ventricular ejection fraction (LVEF ≤35%) is commonly seen in approximately 5% of the myocardial infarction (MI) survivors in its acute-phase, which is recognized as a risk factor of post-MI cardiac death. However, clinical incidence and risk factor of the progressively reduced LVEF in the chronic-phase after MI has not been clarified.

Purpose

To evaluate clinical incidence and risk factor of the progressively reduced LVEF in the chronic-phase after MI by serial echocardiography.

Method

We evaluated 1144 consecutive patients with acute MI with preserved LVEF (≥50%) in acute-phase. Primary outcome was severely reduced LVEF (<35%) in the chronic-pahse. We analyzed the predictive factor using multivariate analysis.

Result

During follow-up (median:1097 days), severely reduced LVEF newly developed in 8.6% of AMI survivors. Kaplan-meier curve is shown in the Figure. Multivariate analysis showed that men, eGFR <30, AMI of LAD and absence of renin-angiotensin system blocking drugs was an independent predictor of severely reduced LVEF.

Conclusions

Progressively reduced LVEF during chronic-phase occurred 8.6% in acute MI survivors with preserved initial LVEF. Especially patients with these risk factors, careful long-term follow-up after MI should be needed to identify possible candidate for the implantable cardioverter-defibrillator.

Figure 1

Funding Acknowledgement

Type of funding source: None

Effectiveness of more strict managements after achievement of standard target value of low-density lipoprotein cholesterol in secondary prevention of Japanese patients

Background

In secondary prevention of coronary artery disease, target value of low-density lipoprotein cholesterol (LDL-C) <100 mg/dL is recommended as standard management in Japanese guideline. The guideline also stated that strict management of LDL-C targeting <70 mg/dL is considered in some high risk patients. However, in Japanese patients, effectiveness of more strict management of LDL-C lowering therapy for prevention of long-term cardiovascular events remains unclear.

Purpose

The purpose of the present study was to evaluate whether the strict management of LDL-C targeting <70 mg/dL was effective to prevent recurrence of long-term coronary events than standard management in patients with previous percutaneous coronary intervention (PCI).

Methods

We investigated 344 patients with previous PCI who underwent late coronary angiography to examine recurrence of cardiac ischemia beyond the early phase of restenosis from January 2007 to August 2019. Patients were stratified into three groups according to achieved LDL-C value; LDL-C <70mg/dL (n=53), 70 to <100mg/dL (n=130) and ≥100mg/dL (n=161). Endpoints of this study were recurrence of cardiac ischemia presenting as acute coronary syndrome (recurrence-ACS) and any late coronary revascularization.

Results

During average 7.1 years follow-up, 200 patients (58%) underwent any late coronary revascularization. In 94 of those patients, recurrence-ACS was observed. The incidence of recurrence-ACS was significantly lower in patients with achieved LDL-C <70mg/dL than in those with LDL-C 70 to <100mg/dL and LDL-C ≥100mg/dL (p=0.009 and p=0.001, respectively), however, there was no difference between patients with LDL-C 70 to <100mg/dL and LDL-C ≥100mg/dL (p=0.140). Any late revascularization was significantly lower in patients with achieved LDL-C <70mg/dL and in those with LDL-C 70 to <100mg/dL than in those with LDL-C ≥100mg/dL (p=0.002 and p<0.001, respectively), however, no difference was found between patients with LDL-C <70mg/dL and LDL-C 70 to <100mg/dL (p=0.119). Moreover, in patients with achieved LDL-C <100mg/dL (n=183), multivariate analysis identified that LDL-C (HR 1.035, p=0.007) and HbA1c (HR 1.338, p=0.001) were independent predictors of recurrence-ACS. In contrast, only using statins (HR 0.461, p=0.009) was an independent predictor of recurrence-ACS in patients with achieved LDL-C ≥100mg/dL.

Conclusions

LDL-C was the important residual risk of recurrence-ACS even after recommended standard LDL-C lowering management had been achieved. More strict management of LDL-C targeting to <70mg/dL should be considered to prevent recurrence-ACS for wider range of Japanese patients in secondary prevention.

Incidence of late coronary events

Funding Acknowledgement

Type of funding source: None

Prognostic impact of initial serum albumin for newly developing heart failure after acute myocardial infarction

Background/Introduction

Previous studies have shown that poor nutritional status relate to the clinical outcomes in patients with heart failure (HF). However, relationships between initial serum albumin and newly developing HF after acute myocardial infarction (AMI) remain unclear.

Methods

We evaluated 2289 consecutive patients with AMI in our hospital. Primary outcome was HF hospitalization after AMI. We analyzed the predictive impact of initial serum albumin using multivariate analysis, both in all AMI patients and subgroup of AMI patient without known risk factors of HF (LMT, peak CK >8000, eGFR <30, and LVEF <35%).

Result

In the remote-phase(median follow-up: 754 days), 5.4% of all AMI patients were hospitalized due to HF. Multivariate analysis showed that low albumin (<4.0g/dl) was an independent predictor of HF hospitalization after AMI in all patients, as well as other known risk factors. Interestingly, low albumin still showed the predictive value even in the no-HF risk subgroup. Kaplan-meier curve of no-HF risk group is shown in the Figure.

Conclusions

Low initial albumin level would be an useful predictor of newly developing HF in the remote-phase after AMI.

Figure 1

Funding Acknowledgement

Type of funding source: None

Catheter ablation of atrial fibrillation benefits the patients with heart failure and preserved ejection fraction as well as those with heart failure and reduced ejection fraction

Background

Although catheter ablation of atrial fibrillation (AF) has recently been shown to improve the cardiac function and even mortality in patients with heart failure (HF) and reduced ejection fraction (HFrEF), few studies have examined the outcomes of AF catheter ablation in patients with HF with preserved ejection fraction (HFpEF).

Purpose

To verify the impact of AF catheter ablation on the cardiac function and HF status in patients with HFpEF.

Methods

We studied 306 patients with HF who had a history of an HF hospitalization and/or preprocedural serum BNP levels >100pg/ml (age, 68.9±8.2 years old; male, 66.3%; non-paroxysmal AF, 63.1%, left atrial diameter [LAD], 42.5±6.3 mm; left ventricular ejection fraction [LVEF], 60.6±12.0%) out of 596 consecutive patients who underwent pulmonary vein isolation-based catheter ablation of AF. The patients with an LVEF ≥50% were defined as having HFpEF (n=262; age, 69.0±8.2 years old; male, 64.5%; non-paroxysmal AF, 61.8%, LAD, 42.1±5.9 mm; left LVEF, 64.0±8.2%) and the remaining patients with an LVEF <50% were defined as having HFrEF (n=44, age, 67.9±8.7 years old; male, 77.0%; non-paroxysmal AF, 70.5%, LAD, 44.9±8.2 mm; LVEF, 40.1±10.2%). The patients received periodic follow-ups for 12 months after the catheter ablation. The cardiac function parameters including the echocardiographic findings and HF functional status of the patients were compared between baseline and 12 months, stratified by the HF subgroup.

Results

AF recurred in 60 patients with HFpEF (22.9%) and in 14 with HFrEF (31.8%) during the 12 month follow-up (p=0.27), however, sinus rhythm was maintained at 12 months in most of the patients (253 patients with HFpEF [96.6%] and 42 patients with HFrEF [95.5%]) (p=0.71). Figure 1 compares the changes in the cardiac function parameters and NYHA functional class from baseline to the 12-month follow-up stratified by the HF subgroup. Both the patients with HFpEF and HFrEF had significant improvements in the serum BNP levels, chest thorax ratio, and LVEF determined by echocardiography. LA reverse remodeling as shown by a significant reduction in the LAD was observed in both HF subgroups, however, the E/E', an index of the LV diastolic function, did not significantly change in either of the subgroups. Similar to the patients with HFrEF, an improvement in the NYHA functional class was seen in those with HFpEF.

Conclusions

Catheter ablation of AF may benefit patients with HFpEF as well as those with HFrEF. Sinus rhythm maintenance achieved by AF catheter ablation in patients with HFpEF may lead to LA reverse remodeling and a better LV systolic function, thereby improving the NYHA functional class. It is unclear whether changes in the LV diastolic function may contribute to this favorable process.

Funding Acknowledgement

Type of funding source: None

Clinical CAR-T Cell and Oncolytic Virotherapy for Cancer Treatment

Immunotherapy has recently garnered success with the induction of clinical responses in tumors, which are traditionally associated with poor outcomes. Chimeric antigen receptor T (CAR-T) cells and oncolytic viruses (OVs) have emerged as promising cancer immunotherapy agents. Herein, we provide an overview of the current clinical status of CAR-T cell and OV therapies. While preclinical studies have demonstrated curative potential, the benefit of CAR-T cells and OVs as single-agent treatments remains limited to a subset of patients. Combinations of different targeted therapies may be required to achieve efficient, durable responses against heterogeneous tumors, as well as the microenvironment. Using a combinatorial approach to take advantage of the unique features of CAR-T cells and OVs with other treatments can produce additive therapeutic effects. This review also discusses ongoing clinical evaluations of these combination strategies for improved outcomes in treatment of resistant malignancies.

Modulating TNFα activity allows transgenic IL15-Expressing CLL-1 CAR T cells to safely eliminate acute myeloid leukemia

Background

C-type lectin-like molecule 1 (CLL-1) is highly expressed in acute myeloid leukemia (AML) but is absent in primitive hematopoietic progenitors, making it an attractive target for a chimeric antigen receptor (CAR) T-cell therapy. Here, we optimized our CLL-1 CAR for anti-leukemic activity in mouse xenograft models of aggressive AML.

Methods

First, we optimized the CLL-1 CAR using different spacer, transmembrane and costimulatory sequences. We used a second retroviral vector to coexpress transgenic IL15. We measured the effects of each construct on T cell phenotype and sequential (recursive) co culture assays with tumor cell targets to determine the durability of the anti tumor activity by flow cytometry. We administered CAR T cells to mice engrafted with patient derived xenografts (PDX) and AML cell line and determined anti tumor activity by bioluminescence imaging and weekly bleeding, measured serum cytokines by multiplex analysis. After euthanasia, we examined formalin-fixed/paraffin embedded sections. Unpaired two-tailed Student’s t-tests were used and values of p<0.05 were considered significant. Survival was calculated using Mantel-Cox log-rank test.

Results

In vitro, CLL-1 CAR T cells with interleukin-15 (IL15) were less terminally differentiated (p<0.0001) and had superior expansion compared with CD28z-CD8 CAR T cells without IL15 (p<0.001). In both AML PDX and AML cell line animal models, CLL-1 CAR T coexpressing transgenic IL15 initially expanded better than CD28z-CD8 CAR T without IL15 (p<0.0001), but produced severe acute toxicity associated with high level production of human tumor necrosis factor α (TNFα), IL15 and IL2. Histopathology showed marked inflammatory changes with tissue damage in lung and liver. This acute toxicity could be managed by two strategies, individually or in combination. The excessive TNF alpha secretion could be blocked with anti-TNF alpha antibody, while excessive T cell expansion could be arrested by activation of an inducible caspase nine safety switch by administration of dimerizing drug. Both strategies successfully prolonged tumor-free survival.

Conclusion

Combinatorial treatment with a TNFα blocking antibody and subsequent activation of the caspase-9 control switch increased the expansion, survival and antileukemic potency of CLL-1 CAR T-cells expressing transgenic IL15 while avoiding the toxicities associated with excessive cytokine production and long-term accumulation of activated T-cells.

AB0619 PROGNOSTIC FACTORS OF PATIENTS WITH ANTI-MDA5 ANTIBODY-POSITIVE DERMATOMYOSITIS COMPLICATED WITH INTERSTITIAL PNEUMONIA -A JAPANESE SINGLE CENTER STUDY-

Background:

Anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab)-positive dermatomyositis (DM) is frequently associated with rapidly progressive interstitial pneumonia (RPIP), whose prognosis is assumed to be poor[1]. Although outcome of DM-RPIP has been reported to be improved by early immunosuppressive therapy, we still experience the cases with severe outcome. Only several reports mentioned the prognostic factors and they have not been fully elucidated.

Objectives:

To identify the predictors of prognosis in patients with anti-MDA5 Ab-positive DM associated with interstitial pneumonia (DM-IP).

Methods:

Anti-MDA5 Ab-positive DM-IP patients admitted to Fujita Health University Hospital between January 2010 and October 2019 were consecutively included and stratified into 2 groups, the survived and the deceased groups. DM was diagnosed according to the criteria proposed by Bohan and Peter[2]. Clinically amyopathic DM was diagnosed according to the criteria proposed by Sontheimer [3]. Diagnosis of IP was based on findings of high resolution CT scan (HRCT). The definition of RPIP was rapid exacerbation of hypoxemia or HRCT findings in a period of days to one month after the onset. Clinical features and prognosis of the patients were collected retrospectively and compared between groups. Candidates of predictors are extracted by the univariable analysis using Fisher’s exact test for dichotic parameters and Wilcoxon signed-rank test for continuous parameters and multivariable analysis using logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was examined to obtain the cut-off level. Survival was examined using Kaplan-Meier method and Log-rank test.

Results:

Twenty-one patients were involved. Eight were deceased and 13 were survived. The deceased group had a higher ratio of male (75% versus 25%, p= 0.018). All deceased cases were with RPIP and 67 % in the survived cases. Levels of serum ferritin (4490 versus 646 ng/mL, p = 0.0026), CRP (2.1 versus 0.9 mg/dL, p = 0.0490), CK (1150 versus 290 U/L, p = 0.017), AST (194 versus 108 U/L, p = 0.025) and LDH (674 versus 368 U/L, p = 0.011) were higher in the deceased group. Interestingly, skin ulcers were tended to be more frequent (12.5% versus 87.5%, p= 0.0587), and anti-SS-A antibody was also more frequently detected (14.3% versus 85.7%, p=0.0072) in the survived group. Using ROC analysis cut-off values were 963 ng/mL for serum ferritin level (sensitivity 100%, specificity 83%), 0.7 mg/dL for CRP (sensitivity 75%, specificity 69%), 308 U/L for CK (sensitivity 88%, specificity 77%), 62 U/L for ALT (sensitivity 100%, specificity 62%), and 454 U/L for LDH (sensitivity 88%, specificity 77%). Patients were divided into two groups based on these cut-offs or based on dichotic parameters and survival was examined between 2 groups. Except CRP and anti-SS-A antibody, survival was significantly worse in parameter-positive or higher groups. Interestingly, anti-SS-A antibody-positive group had better outcome compared with those without.

Conclusion:

In our analysis, novel candidates such as serum CK, AST, and LDH levels were newly extracted and parameters previously reported was also included and those were also associated with the clinical outcome. In addition, anti-SS-A antibody was identified as a novel protective factor associated with a good outcome.

References:

[1]Nakashima R, Hosono Y, Mimori T. Clinical significance and new detection system of autoantibodies in myositis with interstitial lung disease. Lupus 2016;25:925-33.

[2]Bohan A, Peter JB. Polymyositis and dermatomyositis. N Eng J Med 1975;292:344-7.

[3]Sontheimer RD. Dermatomyositis: an overview of recent progress with emphasis on dermatologic aspects. Dermatol Clin 2000;20:387-408.

Disclosure of Interests:

None declared

0634 Volume-Assured Pressure Support is Effective Treatment for Obstructive Sleep Apnea Patients Who Failed CPAP Titration

Introduction

Obstructive sleep apnea (OSA) is a common disease, often treated using continuous positive airway pressure (CPAP). In many cases, patients fail an attended CPAP titration study, often due to inadequate control of AHI, and treatment-emergent central apneas as CPAP is increased. Here, we report our experience using volume-assured pressure support (VAPS) for these patients.

Methods

We retrospectively reviewed records of 45 adults who had OSA diagnosed on polysomnography (PSG) in whom CPAP titration had failed. In these patients, VAPS-AE (adjustable expiratory pressure) titrations were performed. Patients with central sleep apnea on baseline PSG were excluded.

Results

Reasons for CPAP titration failure included: treatment emergent central apneas (25), failure of maximum CPAP pressure to treat OSA (18), and persistent hypoxia (2). Average age was 57.9±13.1, BMI was 40.2±8.7, 26 males, Epworth sleepiness score was 10.7±7.9. The following significant changes from baseline PSG to VAPS titration were observed: AHI: 65.3±29.3 to 22.3 ±16.1 (p&lt;.001) events/hour. Time &lt; 88% saturation: 63.7 (median) to 6.9 (median) min (p&lt;.001). The number of patients with AHI&lt;15 was 0 on PSG and 16 (36%) on VAPS-AE, while the number of patients with AHI&lt;30 was 7 (16%) on PSG and 32 (71%) on VAPS-AE. Improvement in AHI was not related to gender, age, or narcotic use, but was correlated with BMI: ΔAHI = 12.2 - (1.4 * BMI); p=.05. VAPS resulted in improved sleep architecture: slow wave sleep increased (medians: 1.4% to 19.6% total sleep time (TST)) (p&lt;.001), REM sleep increased (medians 6.4% to 13.6% TST) (p&lt;.01).

Conclusion

For OSA patients for whom CPAP titration failed, titration with VAPS-AE was an effective treatment for many patients.

Support

N/A

0633 Volume Assured Pressure Support is an Effective Treatment in Patients with Central Sleep Apnea Syndrome

Introduction

Central sleep apnea syndrome (CSA) is commonly found in patients with congestive heart failure, brainstem disorders, and narcotic use. Various treatment modalities have been used with varied effectiveness in reducing the apnea-hypopnea index (AHI) and improving ventilation in patients with CSA. This study assessed whether Volume Assured Pressure Support (VAPS), a BiLevel mode of ventilation, is effective in treating CSA.

Methods

We performed a retrospective review of polysomnography (PSG) and VAPS titration studies on 11 patients at our institution: 7 patients had CSA with Cheyne-Stokes Respiration, 2 patients had CSA attributed to narcotic use, and 2 patients had primary CSA. CSA was diagnosed if more than 50% of the disordered breathing events were central. Five patients had failed a Continuous Positive Airway Pressure (CPAP) titration and then proceeded to VAPS while in 6 patients, VAPS was the initial treatment modality tried. We examined the effectiveness of VAPS in reducing AHI, improving oxygenation, and improving sleep architecture.

Results

Among the 11 patients, age was 63.0±12.1 yo, BMI was 33.7 ±4.5, 7 were males, Epworth sleepiness score was 9.3±4.9. The following significant changes from baseline PSG to VAPS titration were observed: AHI: 59.1± 8.0 to 27.2 ± 9.9 (p&lt;.01); Time ≤ 88% O2 saturation (min): 48.1±14.5 to 15.4±6.1 (p&lt;.05). Improvement in AHI was not related to gender, body mass index, narcotic use, or age. No significant changes in sleep architecture between the two studies were found. Ten (91%) patients had AHI &gt; 30 on initial PSG. In 6 (55%) patients AHI was reduced to &lt;15 with VAPS use. An additional patient had AHI reduced to 22.2, while 4 (36%) patients did not achieve an AHI &lt; 30 with VAPS.

Conclusion

VAPS is an effective mode of treating CSA in the majority of patients.

Support

NA

P762 Preserved mitral apparatus dynamics predict the improvement of acute ischemic mitral regurgitation: four-dimensional quantitative echocardiographic study

Background

We sought to evaluate the predictive value of acute stage mitral apparatus geometry and dynamics for the reduction of ischemic mitral regurgitation (IMR) in the remote phase after successful primary percutaneous coronary intervention (pPCI) by using real-time 3D-transthoracic echocardiography (3D-TTE).

Methods

We performed 2D and 3D-TTE in consecutive 44 first acute MI patients with more than mild IMR within 3 days after successful pPCI. 3DTTE of left ventricle (LV) volumes and mitral apparatus dynamics through the cardiac cycle were quantified offline. We compared the 3D geometric and dynamic parameters in the acute phase between 1)20 remained MR group and 2)24 improved MR group in 6-to-12 months after MI onset.

Results

Ejection fraction (EF) was preserved in the improved MR group compared to the remained MR group (49.0 ± 11.2 vs. 56.5 ± 7.0%, p = 0.013). Mitral valve annulus area, leaflet tenting length and papillary muscles spatial position had no significant difference between the two groups (all p &gt; 0.05) throughout cardiac cycle. In contrast, mitral annulus saddle shape was preserved in the improved MR group than the remained MR group (p = 0.010) and annular area changed dynamically through early- to late-systole in the improved MR group (phasic p = 0.017) despite it was adynamic in remained MR group (phasic p = 0.201). Conclusions: IMR improvement in the remote phase after AMI associated with preserved EF, mitral annulus saddle shape and dynamics during systole in the acute phase of MI. 4D dynamics of the mitral apparatus can be clinically useful predictor of the improvement in acute IMR and may contribute to the clinical decision making including surgical or percutaneous intervention for IMR.

P292 The risk of adverse outcome with ischemic mitral regurgitation at 6-month after myocardial infarction: possible benefit of early intervention by transcatheter mitral-valve repair

Background

The latest study has demonstrated the better outcomes of transcatheter mitral-valve repair in patients with decompensated heart failure (HF) and left ventricular (LV) dysfunction. However, it is unknown whether earlier intervention for mitral regurgitation (MR) can improve the outcome of myocardial infarction (MI).

Purpose

The aim of this study was to investigate the prognostic value of ischemic MR (IMR) at 6-month after MI for the later incidence of HF and death.

Methods

We retrospectively examined 723 MI patients who were admitted to our hospital. 95.5% of the patients were treated by primary coronary intervention. Patients were clinically followed-up at 6-month after the onset of MI, and divided into 3 groups according to the degree of IMR, i.e. No/Trivial IMR group (n = 528), Mild IMR group (n= 154) and ≥Moderate IMR group (n= 41). We compared the later incidence of hospitalization for HF and all-cause death at 3-year for each group.

Results

The studied population had preserved ejection fraction (EF) (56.9 ± 10.7%, average) and mostly asymptomatic at 6-month after MI. All-cause mortality within 3-year was higher in patients with ≥Moderate IMR (p &lt; 0.001), and the incidence of hospitalization for HF was significantly higher depends on the degree of IMR at 6-month (p &lt; 0.001). Multivariate analysis showed EF and the degree of IMR were the independent predictor for the hospitalization for HF.

Conclusions

IMR at 6-month after MI was associated with the later adverse events despite relatively preserved LV contraction without heart failure symptoms at the index examination. Early intervention for IMR potentially benefit for the better outcome.

Abstract P292 Figure. Caplan-Meier estimates on adverse events

P1520 Aortic flow reversal caused by aortic regurgitation deteriorates renal function

Background

Chronic kidney disease is a growing public health problem. Renal dysfunction is known as a strong risk factor for cardiovascular disease and end-stage renal failure. The presence of pan-diastolic flow reversal in the abdominal aorta is a very specific sign of severe aortic regurgitation (AR). A higher aortic reverse/forward flow ratio is associated with lower intrarenal forward flow. However, the influence of AR on renal function has been poorly understood. We hypothesized that the aortic flow reversal reduces the renal artery forward flow and accordingly leads to renal dysfunction in patients with severe AR.

Methods

The study consisted of 21 consecutive patients (mean age 69 ± 11 years) with severe AR who underwent aortic valve replacement (AVR). We compared echocardiographic indices and the glomerular filtration rate (GFR) before and 603 ± 541 days after AVR.

Results

Blood pressure was 122 ± 16/54 ± 8 mmHg before AVR and 123 ± 16/76 ± 11 mmHg after AVR. After AVR, left ventricular (LV) end-diastolic dimension decreased from 57 ± 9 to 44 ± 5 mm and LV ejection fraction increased from 58 ± 12 to 60 ± 11 %. Estimated GFR significantly increased from 62.9 ± 18.9 to 71.8 ± 18.1 mL/min per 1.73 m2 after AVR (p = 0.003).

Conclusions An increase in aortic flow reversal caused by severe AR reduces forward flow into the kidney and thereby deteriorates renal function. This study demonstrated a key mediating role of central hemodynamic factors, particularly an exaggerated aortic flow reversal in renal dysfunction and severe AR.

mDia1/3-dependent actin polymerization spatiotemporally controls LAT phosphorylation by Zap70 at the immune synapse

The mechanism by which the cytosolic protein Zap70 physically interacts with and phosphorylates its substrate, the transmembrane protein LAT, upon T cell receptor (TCR) stimulation remains largely obscure. In this study, we found that the pharmacological inhibition of formins, a major class of actin nucleators, suppressed LAT phosphorylation by Zap70, despite TCR stimulation-dependent phosphorylation of Zap70 remaining intact. High-resolution imaging and three-dimensional image reconstruction revealed that localization of phosphorylated Zap70 to the immune synapse (IS) and subsequent LAT phosphorylation are critically dependent on formin-mediated actin polymerization. Using knockout mice, we identify mDia1 and mDia3, which are highly expressed in T cells and which localize to the IS upon TCR activation, as the critical formins mediating this process. Our findings therefore describe previously unsuspected roles for mDia1 and mDia3 in the spatiotemporal control of Zap70-dependent LAT phosphorylation at the IS through regulation of filamentous actin, and underscore their physiological importance in TCR signaling.

1182 Clinical evidence of the mitral valve leaflet remodeling after st-elevation acute myocardial infarction: longitudinal observation using real-time 3D echocardiography

Background

Mitral valve (MV) leaflet remodeling after acute myocardial infarction (AMI) has been proposed as biological and physiological reaction under the ischemic environment mainly by animal experiments. Clinical evidence of leaflet growth after AMI is lacking.

Purpose

We aimed to assess the clinical evidence of the mitral valve leaflet remodeling after acute myocardial infarction by serial 2D/3D transthoracic echocardiography.

Methods

Sixty-six patients with first-onset ST-elevation MI (33 anterior and 33 inferior) were serially examined by 2D/3D-transthoracic echocardiography. MV complex geometry including leaflet surface area and leaflet thickness was quantitatively analyzed in acute phase and 6-month follow-up.

Results

3D-leaflet surface area was significantly increased in 6-month follow-up (anterior MI; 5.58 [4.93-6.00] versus 5.98 [5.68-6.40] cm²/m²; P &lt; 0.001, inferior MI; 5.48 [4.69-6.07] versus 5.79 [4.74-6.37] cm²/m²; P &lt; 0.001). In anterior MI, both anterior and posterior leaflet lengths significantly increased (anterior leaflet; 12.78 [11.55-13.55] versus 13.63 [12.52-14.15] mm/m²; P = 0.001, posterior leaflet; 9.61 [8.73-10.77] versus 9.84 [8.94-10.96] mm/m²; P = 0.037). In inferior MI, posterior leaflet length significantly increased (9.18 [8.50-10.38] versus 10.00 [8.56-10.85] mm/m²; P = 0.029), while there was no significant change in anterior leaflet length (12.54 [11.61-13.56] versus 12.56 [12.08-14.06] mm/m²; P = 0.214). Leaflet thickness was found to become greater in both groups in 6-month follow-up (anterior MI; 1.08 [0.92-1.21] versus 1.32 [1.25-1.45] mm; P &lt; 0.001, inferior MI; 1.14 [0.98-1.25] versus 1.32 [1.21-1.49] mm; P &lt; 0.001) (Figure).

Conclusions

In six months from the onset of AMI, MV enlarged in area and increased in thickness. Anterior leaflet mainly enlarged in anterior MI, while posterior leaflet enlarged in inferior MI. This is the first clinical evidence of the MV remodeling after AMI, and long-year follow-up should contribute to assess the course of valve growth with relation to ischemic mitral regurgitation.

Abstract 1182 Figure. 3D analysis of the mitral valve

Polymer gel with a flexible and highly ordered three-dimensional network synthesized via bond percolation

Gels are a soft elastic material consisting of a three-dimensional polymer network with nanometer-sized pores and are used in a variety of applications. However, gel networks typically have a substantial level of defects because the network formation reaction proceeds stochastically. In this study, we present a general scheme to fabricate gels with extremely low levels of defects by applying geometric constraints into pregel solution based on the "bond percolation" concept. In the formed gel, stationary laser speckles, which are an indicator of spatial defects, were not observed at all. In addition, we found that the concentration fluctuations of the polymer chains were ergodic across the whole gel network. In such a homogeneous gel, both the spatial and temporal correlations of polymer chains are the same before and after gelation.

Expanding CAR T cells in human platelet lysate renders T cells with in vivo longevity

BACKGROUND

Pre-clinical and clinical studies have shown that the infusion of CAR T cells with a naive-like (T_N) and central memory (T_CM) phenotype is associated with prolonged in vivo T cell persistence and superior anti-tumor effects. To optimize the maintenance of such populations during the in vitro preparation process, we explored the impact of T cell exposure to both traditional [fetal bovine serum (FBS), human AB serum (ABS)] and non-traditional [human platelet lysate (HPL) - a xeno-free protein supplement primarily used for the production of clinical grade mesenchymal stromal / stem cells (MSCs)] serum supplements.

METHODS

Second generation chimeric antigen receptor with CD28 and CD3ζ endodomain targeting prostate stem cell antigen (PSCA) (P28z) or CD19 (1928z) were constructed and used for this study. After retroviral transduction, CAR T cells were divided into 3 conditions containing either FBS, ABS or HPL and expanded for 7 days. To evaluate the effect of different sera on CAR T cell function, we performed a series of in vitro and in vivo experiments.

RESULTS

HPL-exposed CAR T cells exhibited the less differentiated T cell phenotype and gene signature, which displayed inferior short-term killing abilities (compared to their FBS- or ABS-cultured counterparts) but superior proliferative and anti-tumor effects in long-term in vitro coculture experiments. Importantly, in mouse xenograft model, HPL-exposed CAR T cells outperformed their ABS or FBS counterparts against both subcutaneous tumor (P28z T cells against Capan-1^PSCA) and systemic tumor (1928z T cells against NALM6). We further observed maintenance of less differentiated T cell phenotype in HPL-exposed 1928z T cells generated from patient's PBMCs with superior anti-tumor effect in long-term in vitro coculture experiments.

CONCLUSIONS

Our study highlights the importance of serum choice in the generation of CAR T cells for clinical use.

P3619Incidence of progressively reduced LVEF during long-year follow-up after myocardial infarction: impact for mid-term outcomes

Background

Severely reduced left ventricular ejection fraction (LVEF≤35%) is commonly seen in approximately 5% of the myocardial infarction (MI) survivors in its acute-phase, which is recognized as a risk factor of post-MI cardiac death. However, clinical impact of the progressively reduced LVEF in the chronic-phase after MI has not been clarified.

Purpose

To evaluate clinical impact of the progressively reduced LVEF in the chronic-phase after MI.

Method

We evaluated 1659 consecutive patients with acute MI by serial echocardiography. Primary outcome was severely reduced LVEF. And secondary outcome was all cause death and cardiac death.

Result

During follow-up (median: 1097 days), severely reduced LVEF newly developed in 8.6% of AMI survivors. These patients had significantly higher incidence of all cause death (20.7% vs. 4.4%, p<0.01) and cardiac death (10.6% vs. 1.2%, p<0.01) than those with LVEF>35%. Severely reduced LVEF progressed in the chronic-phase associated with all cause death and cardiac death as well as those with severely reduced EF in the acute-phase.

Figure 1

Conclusions

Progressively reduced LVEF during chronic-phase occurred 8.6% per 10-year in MI survivors. Careful long-term follow-up after MI should be needed to identify possible candidate for the implantable cardioverter-defibrillator.

P642What is the most important residual risk after achievement of appropriate low-density lipoprotein cholesterol lowering therapy in secondary prevention of Japanese patients?

Background

In secondary prevention of coronary artery disease, target value of low-density lipoprotein cholesterol (LDL-C) <100mg/dL with using statins is recommended as standard therapy in Japanese guideline. However, impact of residual risks after achievement of standard LDL-C lowering therapy was not fully examined. Furthermore, there is little information whether more strict management of LDL-C lowering is effective to prevent long-term cardiovascular events than standard management.

Purpose

The purpose of this study was to evaluate the relationship between residual risks after achievement of standard LDL-C lowering therapy and long-term coronary events in secondary prevention of Japanese patients.

Methods

From January 2007 to August 2018, 333 patients with previous percutaneous coronary intervention underwent late coronary angiography to examine recurrence of cardiac ischemia beyond the early phase of restenosis. We defined appropriate LDL-C lowering therapy as achieved LDL-C <100mg/dL with using statins. Patients whose achieved LDL-C was <100mg/dL with using statins were classified as Appropriate-group (n=139), and patients who were not using statins or whose achieved LDL-C was ≥100mg/dL were classified as Inappropriate-group (n=194). Endpoints of the study were recurrence of cardiac ischemia as acute coronary syndrome (recurrence-ACS) and any late coronary revascularization.

Results

During average 7.1 years follow-up, 195 patients (59%) underwent any late coronary revascularization. In 91 of those patients, clinical presentation of recurrence-ACS was observed. Kaplan-Meier curve analysis revealed that the incidence of recurrence-ACS and any late coronary revascularization were significantly lower in Appropriate-group than in Inappropriate-group (p=0.017 and p<0.001, respectively). In Appropriate-group, recurrence-ACS was significantly lower in patients with achieved LDL-C <70mg/dL than in those with LDL-C 70 to <100mg/dL (p=0.042), however, any late revascularization was not different between the two groups. On the other hand, in Inappropriate-group, recurrence-ACS was significantly lower in patients with using statins than in those without using statins (p=0.038), and any late revascularization was less frequent in patients with achieved LDL-C <100mg/dL than in those with LDL-C ≥100mg/dL (p=0.035). Moreover, multivariate analysis identified that only LDL-C was an independent predictor of recurrence-ACS in Appropriate-group (HR: 1.047, p=0.006), in contrast, LDL-C (HR: 1.008, p=0.020), using statins (HR: 0.555, p=0.034) and triglyceride (HR: 1.003, p=0.038) were independent predictors of recurrence-ACS in Inappropriate-group.

Conclusions

LDL-C was the most important residual risk of recurrence-ACS even after recommended standard therapy has been achieved. More strict management of LDL-C targeting to <70mg/dL should be considered in secondary prevention of Japanese patients.

P3604Gender difference in Low-BMI patients with acute myocardial infarction makes an impact on mid-term outcomes

Background/Introduction

There are some reports about impact of low body-mass-index (BMI) on patients with acute myocardial infarction (MI), suggesting an obesity paradox. However, the differential impact of gender between low-BMI and mid-term outcome remains unclear.

Purpose

To evaluate the differential impact of gender between low-BMI patients with acute MI and mid-term outcome.

Methods

We evaluated 3038 consecutive patients with acute MI in Miyazaki medical association hospital. Patients were stratified low-BMI group (BMI≤20) from other-BMI group (BMI>20), and compared. BMI was measured at admission of acute MI. Primary outcome was cardiac death. We also analyzed each gender, using Kaplan-meier curve with long-rank test.

Result

Among all patients, low-BMI patient was 8.6%. Median follow-up was 1085 days, and cardiac death was significantly higher rate in low-BMI group (14.5% vs 7.7%, p<0.001). Male patient with low-BMI was significantly higher event rate, compared with other-BMI group (11.0% vs 5.5%, p<0.001). However, female patient group had no significant difference of outcomes between low-BMI and other-BMI (12.6% vs 10.3%, p=0.315). Event rate is shown in the Figure.

Gender

Conclusions

Low BMI was associated with mid-term outcomes in acute MI patients. Impact of low-BMI on mid-term outcome seems to be gender dependent in acute MI patients.

P1038Device implantation after catheter ablation of paroxysmal atrial fibrillation with coexisting sick sinus syndrome: Insights from the Kansai Plus Atrial Fibrillation (KPAF) study

Background

Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist and interact to initiate and perpetuate each other. Several retrospective or small cohort studies have suggested that successful catheter ablation of AF may help to waive device implantations in patients with paroxysmal AF plus SSS, however, no prospective large studies are so far available on this scenario.

Purpose

We aimed to elucidate the device implantation-free survival after catheter ablation of paroxysmal AF with coexisting SSS in a prospective large-scale registry. We also determined the risk factors for device implantations after catheter ablation of paroxysmal AF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) study is a multi-center prospective registry that enrolled 5,019 consecutive patients that underwent an initial pulmonary vein isolation-based radiofrequency catheter ablation of AF. This study was comprised of 3,226 patients with paroxysmal AF registered in the KPAF study (age, 64.8±10.5 years old; female, n=999 [31.0%]; left atrial diameter [LAD], 37.5±8.0 mm; left ventricular ejection fraction [LVEF], 65.3±8.4%, CHADS2 score, 1.09±1.05). The atrial tachyarrhythmia-free and device-free survivals after catheter ablation were compared between patients with SSS (n=368; tachy-brady syndrome, 88%) and without SSS (control; n=2,858).

Results

The atrial tachyarrhythmia-free survival was almost identical between the two groups both after the first ablation session (Fig.1A) and after the last procedure with an average of 1.3±0.5 sessions. At baseline, the devices had already been implanted in 53 (14.4%) SSS and 36 (1.3%) control patients. In the remaining patients, devices were newly implanted in 54 (17.1%) SSS and 62 (2.2%) control patients during the follow-up of 3 years after the catheter ablation (Figure 1B). In the SSS group, devices were implanted predominantly within 6 months after the catheter ablation, and atrial tachyarrhythmia recurrence preceded the device implantation in 48 (89%) patients. Multivariate predictors of device implantations after the paroxysmal AF ablation included: SSS (hazard ratio [HR] 6.85, 95% confidence interval [CI] 4.61–10.19, p<0.001), an age>75 years old (HR 1.69, 95% CI 1.08–2.64, p=0.019), a female gender (HR 2.16, 95% CI 1.44–3.24, p<0.001), the LAD (mm) (HR 1.05, 95% CI 1.02–1.08, p=0.006), and the LVEF (%) (95% CI 0.96, 95% CI 0.94–0.98, p<0.001).

Figure 1

Conclusions

Device implantations could be waived in >80% of patients with SSS at 3 years of follow-up after the catheter ablation of paroxysmal AF in this real world all comer prospective registry. In addition to coexisting SSS, predictors of device implantations after paroxysmal AF ablation included: the elderly, a female gender, a large LA, and a reduced LVEF.

Acknowledgement/Funding

None

Benign hilar bile duct strictures resected as perihilar cholangiocarcinoma

BACKGROUND

Differentiation between perihilar cholangiocarcinoma (PHCC) and benign strictures is frequently difficult. The aim of this study was to investigate the incidence and long-term outcome of patients with tumours resected because of suspicion of PHCC, which ultimately turned out to be benign (malignancy masquerade).

METHODS

Patients who underwent surgical resection with a diagnosis of PHCC between 2001 and 2016 were reviewed retrospectively.

RESULTS

Among 707 consecutive patients, 685 had PHCC and the remaining 22 (3·1 per cent) had benign biliary stricture. All patients with benign disease underwent major hepatectomy, with no deaths. Preoperative histological assessment using bile duct biopsy or aspiration cytology had a high specificity (90 per cent), low sensitivity (62 per cent) and unsatisfactory accuracy (63 per cent). Despite the increasing use of histological assessment, the incidence of benign strictures resected did not decrease over time, being 0·9 per cent in 2001-2004, 4·0 per cent in 2005-2008, 3·8 per cent in 2009-2012 and 2·9 per cent in 2013-2016. The final pathology of benign strictures included IgG4-related sclerosing cholangitis (9 patients), hepatolithiasis (4), granulomatous cholangitis (3), non-specific chronic cholangitis (3), benign strictures after cholecystectomy (2), and a benign stricture possibly caused by parasitic infection (1). The 10-year overall survival rate for the 22 patients with benign stricture was 87 per cent, without recurrence of biliary stricture.

CONCLUSION

The incidence of benign strictures resected as PHCC as a proportion of all resections was relatively low, at 3·1 per cent. Currently, unnecessary surgery for suspected PHCC is unavoidable.

Continuous cell culture monitoring using a compact microplate reader with a silicone optical technology-based spatial filter

Continuous cell monitoring is very important for the maintenance and control of cell multiplication and differentiation. This paper presents a compact microplate reader that is able to continuously measure a 24-well microplate (6 × 4 wells) using the optical absorption measurement method. The 24-channel plate reader consisted of a spatial filter, light emitting diode light source, and color sensors and was similarly sized with the cell culture microwell plates. A spatial filter was previously fabricated by our group using silicone optical technology (SOT). This SOT-based spatial filter has an excellent noise reduction effect. Light reflection at the optical path interface can be absorbed and only forward light can be transmitted; accordingly, a larger S/N ratio than that of conventional optical systems is expected. The fabricated 24-channel plate reader permits real-time cell monitoring during cultivation on the clean bench and in cell culture conditions by incorporating the SOT spatial filter. Using the device, it was possible to continuously evaluate the concentration and pH of reagents in the 24 wells in real time. Moreover, cell activity and protein production were detectable using the device. These results suggest that the newly fabricated device is a promising tool for the evaluation of cell behaviors for cell management.

Major hepatectomy with or without pancreatoduodenectomy for advanced gallbladder cancer

BACKGROUND

The indications for major hepatectomy for gallbladder cancer either with or without pancreatoduodenectomy remain controversial. The clinical value of these extended procedures was evaluated in this study.

METHODS

Patients who underwent major hepatectomy for gallbladder cancer between 1996 and 2016 were identified from a prospectively compiled database. Postoperative outcomes and overall survival were compared between patients undergoing major hepatectomy alone or combined with pancreatoduodenectomy (HPD).

RESULTS

Seventy-nine patients underwent major hepatectomy alone and 38 patients had HPD. The patients who underwent HPD were more likely to have T4 disease (P < 0·001), nodal metastasis (P = 0·015) and periaortic nodal metastasis (P = 0·006), but were less likely to receive adjuvant therapy (P = 0·006). HPD was associated with a high incidence of grade III or higher complications (P = 0·002) and death (P = 0·037). Overall survival was longer in patients who underwent major hepatectomy alone than in patients who underwent HPD (median survival time 32 versus 10 months; P < 0·001). In multivariable analysis, surgery in the early period (1996-2006) (P = 0·002), pathological T4 disease (P = 0·005) and distant metastasis (P < 0·001) were associated with shorter overall survival, and cystic duct tumour (P = 0·002) with longer overall survival.

CONCLUSION

Major hepatectomy alone for gallbladder cancer contributes to favourable overall survival with low morbidity and mortality, whereas HPD is associated with poor overall survival and high morbidity and mortality rates. HPD may eradicate locally spreading gallbladder cancer; however, the indication for the procedure is questioned from an oncological viewpoint.