Induction of Immunological Antitumor Effects by the Combination of Adenovirus-Mediated Gene Transfer of B7-1 and Anti-Programmed Cell Death-1 Antibody in a Murine Squamous Cell Carcinoma Model

BACKGROUND

The goal of this study was to evaluate the antitumor immune effects of B7-1 gene expression in addition to immune checkpoint inhibitor against squamous cell carcinoma.

METHODS

A murine SCC cell line, KLN205, was infected with adenoviral vector carrying B7-1 (AdB7). Infected cells were injected subcutaneously in the flanks of DBA/2 mice. Three weeks after implantation, anti-mouse PD-1 antibody (antiPD1) was intraperitonially administrated twice a week for a total of six times.

RESULTS

CD80 was significantly overexpressed in the AdB7-infected tumors. IFN-gamma in the T cells in the spleen was significantly increased and tumor size was significantly reduced in the mice treated with both AdB7 and antiPD1. Targeted tumors treated with both AdB7 and antiPD1 exhibited significantly increased cell densities of total immune cells as well as Ki-67+ CD8+ T cells and decreased regulatory T cells.

CONCLUSIONS

These results suggest that the B7-1 gene transfer may enhance the antitumor effect of anti-PD1 antibody against SCC.

First Observation of Electron Scattering from Online-Produced Radioactive Target

We successfully performed electron scattering off unstable nuclei which were produced online from the photofission of uranium. The target ^{137}Cs ions were trapped with a new target-forming technique that makes a high-density stationary target from a small number of ions by confining them in an electron storage ring. After developments of target generation and transportation systems and the beam stacking method to increase the ion beam intensity up to approximately 2×10^{7} ions per pulse beam, an average luminosity of 0.9×10^{26}  cm^{-2} s^{-1} was achieved for ^{137}Cs. The obtained angular distribution of elastically scattered electrons is consistent with a calculation. This success marks the realization of the anticipated femtoscope which clarifies the structures of exotic and short-lived unstable nuclei.

Pleural empyema with gas formation caused by mixed infection of Edwardsiella tarda with Streptococcus constellatus

Edwardsiella tarda is an anaerobic, gram‐negative rod bacterium associated with freshwater and marine life. Human E. tarda infections are rare, and most infections in humans cause gastroenteritis. Extraintestinal infections of E. tarda such as pleural empyema are particularly rare. A 72‐year‐old man was admitted with cough and purulent sputum. His medical history included periodontal disease and gastric cancer for which he had undergone total gastrectomy. Chest computed tomography showed left pleural effusion with foci of gas, and both E. tarda and Streptococcus constellatus were cultured from the pleural effusion. Thus, he was diagnosed with gas‐forming empyema. He was successfully treated with therapeutic thoracentesis and antibiotics. Our case suggests that a dietary habit of raw fish, undernutrition, gastrectomy and oral infection may be predisposing factors for empyema caused by E. tarda.

Reconstruction of the external auditory canal using full-thickness rolled-up skin graft after lateral temporal bone resection for T1 and T2 external auditory canal cancer

OBJECTIVE

To present our results of the external auditory canal (EAC) reconstruction procedure using rolled-up full-thickness skin graft with tympanoplasty after lateral temporal bone resection (LTBR) for early-stage EAC carcinoma.

PATIENTS AND METHODS

A retrospective review of 15 patients who had undergone LTBR with reconstruction of the EAC for T1 and T2 EAC cancer between 2016 and 2020.

RESULTS

Postoperative mean air-bone gap was 30.7 decibel hearing level. Although a few patients experienced chronic granulation, persistent otorrhea, and/or laterization of the tympanic membrane, most patients showed no serious complications related to the EAC reconstruction.

CONCLUSION

EAC reconstruction using a full-thickness skin graft in combination with tympanoplasty is useful for minimizing the hearing loss, maintaining the cosmetic appearance, and facilitating the observation into the ear cavity.

Insufficient lipid lowering therapy could not bring favorable prognostic effect in high risk patients who were functionally deferred percutaneous coronary intervention

Introduction

Deferral of percutaneous coronary intervention (PCI) of a functionally insignificant stenosis is associated with favorable long-term prognoses. However, previous reports revealed that patients with fractional flow reserve (FFR) 0.81–0.85 had higher cardiovascular adverse event rates than those with FFR >0.85. Numbers of large clinical trials established the lower, the better strategy for low-density lipoprotein cholesterol (LDL-C) management for patients after PCI. However, in the real clinical practice, the achievement rate of target LDL-C is often insufficient in patients with atherosclerotic risk factors who were functionally deferred PCI.

Purpose

We aimed to examine optimal LDL-C management for patients with intermediate coronary stenosis deferred PCI by FFR measurement.

Methods

This observational study included 293 consecutive patients with coronary stenosis deferred PCI due to greater FFR than 0.80. We separately analyzed 90 patients with 0.81–0.85 of FFR and 203 patients with >0.85. Patients in each group were further classified into 2 groups based on LDL-C level at one year after FFR measurement; the Lower LDL-C group (<100 mg/dL) and the Higher LDL-C group (>100 mg/dL). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE) including death, non-fatal myocardial infarction, ischemic stroke, heart failure hospitalization and unplanned revascularization.

Results

Patients with FFR 0.81–0.85 had a significantly higher MACCE rate than those with FFR >0.85 (hazard ratio (HR): 1.77, 95% confidence interval (CI): 1.02–3.07, p=0.043). In patients with FFR 0.81–0.85, the Lower LDL-C group (n-=53) had a significantly lower rate of the primary endpoint than the Higher LDL-C group (HR: 0.41, 95% CI: 0.18–0.97, Log-rank p=0.036, Figure A). Whereas, there was no significant difference in the event rate between 2 groups in patients with FFR >0.85 (Log-rank p=0.42, Figure B).

Conclusion

Uncontrolled LDL-C level was associated with higher MACCE rate in patients who were deferred PCI due to FFR 0.81–0.85. These results suggested that even in patients who were deferred PCI, those with coronary artery stenosis of lower FFR value should receive strict LDL-C lowering therapy with close monitoring.

Figure 1

Funding Acknowledgement

Type of funding source: None

The clinical and pathological features of intraplaque hemorrhage in coronary artery -insights from Japan DCA registry-

Introduction

Intraplaque hemorrhage (IPH) is known to play an important role in plaque vulnerability in coronary artery. However, the biological reaction in IPH and clinical features of patients with IPH remain unknown, since most histological studies of IPH in coronary artery were performed on autopsy cases. Directional coronary atherectomy (DCA) enables the direct pathological evaluation of collected tissue from “living” patients.

Purpose

We aimed to clarify the clinical presentations and histopathologic features of IPH using specimens obtained by DCA.

Method

This multicentral prospective observational study included consecutive patients who underwent percutaneous coronary intervention for de novo lesions using DCA from June 2015 to February 2018. Histopathological sections that were collected from coronary plaques by DCA were evaluated and classified by the presence of IPH. IPH in DCA specimens was defined as clusters of hemosiderin (Figure A, arrows), erythrocytes (Figure B, arrow heads) and fibrin (Figure C, arrows) within the coronary plaque. A total of 154 de novo lesions from 154 patients were ultimately analyzed, and were divided into IPH group (n=37) and non-IPH group (n=117).

Result

Clinical profiles of patients in the two groups were comparable, except that unstable angina rather than chronic coronary syndrome was significantly more prevalent in the IPH group (32.4% vs. 16.2%, P=0.04). Histopathological analysis showed a significantly higher incidence of cellular-rich plaque (46.0% vs. 25.6%, P=0.02) and spindle-shaped cells (18.9% vs. 6.0%, P=0.02), which indicate active cell proliferations, in the IPH group. The prevalence of necrotic core was also higher in IPH group compared to non-IPH group (48.7% vs. 13.7%, P<0.01).

Conclusion

Pathohistological analysis revealed that coronary plaques with IPH had an active cell proliferation, and patients with IPH likely to had clinical presentations of unstable angina.

Figure 1

Funding Acknowledgement

Type of funding source: None

Comfort and safety of bronchoscopy performed under sedation and local anesthesia in elderly patients

Although sedation for bronchoscopy improves patient comfort, there is a risk of oversedation in elderly patients. Only a few studies have evaluated the efficacy and safety of sedation for bronchoscopy in elderly patients.This study retrospectively analyzed records of 210 patients who underwent transbronchial brushing and/or biopsy under midazolam sedation at National Hospital Organization Omuta National Hospital between June 2017 and October 2019. Patients were administered 1 mg midazolam following 10 mL 4% lidocaine inhalation. When sedation was insufficient, 0.5 mg midazolam was administered additionally. Diagnostic yield, incidence of complications, amount of oxygen supplementation, decreases in percutaneous oxygen saturation (SpO2), changes in blood pressure, and degree of comfort were analyzed.Patients were divided into the elderly (n = 102) and non-elderly (n = 108) groups. No significant differences were observed in diagnostic yield and procedure time between the 2 groups, and no severe adverse events were noted in the elderly group. The degree of comfort during bronchoscopy was significantly higher in the elderly group. In patients administered < 2 mg midazolam, the amount of oxygen supplementation and decreases in SpO2 were significantly smaller in the elderly group compared to the non-elderly group.The risk of adverse events related to midazolam sedation in bronchoscopy does not increase with age, and sedation improves comfort during flexible bronchoscopy in elderly patients. Moreover, a total dose of midazolam <2 mg is safe for elderly patients undergoing bronchoscopy.

Gradient subthalamic neurodegeneration and tau pathology in the hypoglossal nucleus as essential pathological markers of progressive supranuclear palsy - Richardson syndrome

Progressive supranuclear palsy - Richardson syndrome (PSP-RS) was first described in 1964 by Steele et al. Tau pathology has not been reported in the hypoglossal nuclei of PSP-RS patients, whereas Steele et al. described gliosis with no remarkable neuronal losses in the hypoglossal nucleus. This study aimed to investigate the distribution and degree of tau pathology-associated neurodegeneration, with an emphasis on the hypoglossal nucleus, in patients with PSP-RS. Six clinicopathologically proven PSP-RS cases were included in this study. All patients were clinicopathologically and immunohistochemically re-evaluated. This study confirmed the following neuropathological characteristics of PSP-RS: (1) neurodegeneration usually affects the striatonigral system and cerebellar dentate nucleus; (2) the cerebellar afferent system in PSP-RS is affected by absent-to-mild neurodegeneration; and (3) the extent of tau distribution throughout the central nervous system is greater than the extent of neurodegeneration. Furthermore, we found that subthalamic neurodegeneration was more prominent in the ventromedial region than in the dorsolateral region. Nevertheless, the tau pathology showed no remarkable differences between these two sites. Interestingly, the tau pathology was frequently observed in the hypoglossal nuclei of PSP-RS patients. Gradient neurodegeneration of the subthalamus and tau pathology in the hypoglossal nucleus could be regarded as essential pathological features of PSP-RS.

Predictive performance of eleven pharmacokinetic models for propofol infusion in children for long-duration anaesthesia

Background

Predictive performance of eleven published propofol pharmacokinetic models was evaluated for long-duration propofol infusion in children.

Methods

Twenty-one aged three-11 yr ASA I-II patients were included. Anaesthesia was induced with propofol or sevoflurane, and maintained with propofol, remifentanil, and fentanyl. Propofol was continuously infused at rates of 4-14 mg kg  - 1 h - 1 after an initial bolus of 1.5-2.0 mg kg  - 1 . Venous blood samples were obtained every 30-60 min for five h and then every 60-120 min after five h from the start of propofol administration, and immediately after the end of propofol administration. Model performance was assessed with prediction error (PE) derivatives including divergence PE, median PE (MDPE), and median absolute PE (MDAPE) as time-related PE shift, measures for bias, and inaccuracy, respectively.

Results

We collected 85 samples over 270 (130) (88-545), mean (SD) (range), min. The Short model for children, and the Schüttler general-purpose model had acceptable performance (-20%≤MDPE ≤ 20%, MDAPE ≤ 30%, -4% h - 1  ≤   divergence PE ≤ 4% h - 1 ). The Short model showed the best performance with the maximum predictive performance metric. Two models developed only using bolus dosing (Shangguan and Saint-Maurice models) and the Paedfusor of the remaining nine models had significant negative divergence PE (≤-6.1% h - 1 ).

Conclusions

The Short model performed well during continuous infusion up to 545 min. This model might be preferable for target-controlled infusion for long-duration anaesthesia in children.

Graft Protective Effect of HMG-CoA Reductase Inhibitor Pravastatin in Murine Cardiac Allograft Transplantation

The HMG-CoA reductase inhibitor (statin), which reduces serum cholesterol, has been demonstrated in the control of immune responses and may potentially play an important role in the regulation of acute and chronic rejection in organ transplantations. We investigated the graft-protective effect of a kind of statin, pravastatin, in the survival of fully major histocompatibility complex--mismatched murine cardiac allograft transplantation. Fully vascularized heterotopic hearts from C57BL/6 donors were transplanted into CBA recipients through microsurgical techniques. CBA recipients transplanted with a C57BL/6 heart received oral administration of 40, 120, or 400 μg/kg/day of pravastatin from the day of transplantation to 7 days afterward. Immunohistochemical staining studies were performed to determine whether intimal formation of coronary arteries in the transplanted cardiac allografts was preserved and also to conduct morphometric analysis. Untreated CBA recipients rejected C57BL/6 cardiac grafts acutely (median survival time [MST] 7 days). CBA recipients exposed with 40 and 120 μg/kg/day of pravastatin had a small prolonged allograft survival (MSTs of 10 and 9 days, respectively). However, the MST of CBA recipients exposed to 400 μg/kg/day of pravastatin was significantly effective for allograft survival (MST 50 days). Immunohistochemical staining assessments on 4 weeks after grafting showed suppression of intimal hyperplasia in allograft coronary arteries. Pravastatin could induce the prolongation of fully major histocompatibility complex--mismatched cardiac allograft through the protection of the coronary artery.

Administration of Thrombomodulin (CD141) Could Improve Cardiac Allograft Survival in Mice

Thrombomodulin (TM) is a promising natural anti-coagulant therapeutic protein that is effective in the treatment of disseminated intravascular coagulation. However, the mechanisms by which TM on micro-vessels enable the regulation of intimal hyperplasia remain elusive. We investigated the graft-protective effects of TM in a fully major histocompatibility complex-mismatched murine cardiac allograft transplantation model. CBA recipients transplanted with a C57BL/6 heart received intraperitoneal administration of 0.2, 2.0, and 20.0 μg/day of TM for 8 days. Histological staining was conducted to assess the degree of inflammation and infiltration in the transplanted cardiac grafts. Untreated CBA recipients rejected C57BL/6 cardiac grafts acutely (median survival time [MST] was 7 days). CBA recipients exposed to the above dosages had significantly prolonged allograft survival (MSTs were 16, 21, and 37.5 days, respectively). Histologic assessments from TM-exposed recipients 2 weeks after grafting showed that the myocardium and vessel structure in their allografts were clearly preserved, and that the infiltration of inflammatory cells around coronary arteries was suppressed. TM can induce the prolongation of fully major histocompatibility complex-mismatched cardiac allograft by exerting graft protective effects within the myocardium and coronary arteries.

Microwave oscillator using piezoelectric thin-film resonator aiming for ultraminiaturization of atomic clock

We developed a microwave oscillator and a micro electromechanical systems-based rubidium cell for the miniaturization of atomic clocks. A thin-film bulk acoustic resonator (FBAR) having a resonant frequency of the fundamental mode in the 3.5 GHz band was employed instead of a crystal resonator. It delivers a clock transition frequency of Rb atoms of 3.417 GHz without the need for a complicated frequency multiplication using a phase-locked loop. This topology considerably reduces the system scale and power consumption. For downsizing the atomic clock system toward the chip level as well as mass production, a microfabricated gas cell containing Rb and N₂ gases was also developed. These microcomponents were incorporated into an atomic clock test bench, resulting in a clock operation with a short-term frequency instability of 2.1 × 10^-11 at 1 s. To the best of our knowledge, this is the first report of a coherent population trapping clock operation using an FBAR-based microwave oscillator as well as a microfabricated gas cell.

Supporting Endgame Strategy in Tobacco Control

Background and context: Finland has set itself the goal of ending the use of tobacco and other nicotine products by 2030. This would mean that <5% of the adult population would use tobacco and nicotine products daily. This goal has been set out in the Tobacco Act (2016). To help realize the goal, a working group appointed by the Ministry of Social Affairs and Health proposed 31 May 2018 a roadmap of measures. How does the Cancer Society of Finland best support these actions? Aim: Tobacco control is at the core focus of cancer prevention. The Cancer Society's strategic purpose is beating cancer. Strategy/Tactics: The Cancer Society of Finland supports advocacy work for tobacco- and nicotine-free Finland 2030 within several networks. The society has identified its strategic position in tobacco-control activities. Both its strategy and its communications need to be responsive and flexible. When creating awareness on societal level of cancer burden, we must not forget the role of the tobacco industry. Analyzing tobacco industry arguments and use of media is part of our strategic planning. Because tobacco industry strategies are global, the arguments it deploys can be anticipated. In Europe, third-party strategies and criticism toward regulation are among the usual industry tactics and are well documented. Program/Policy process: Tobacco-control legislation in Finland has been well received. One role for NGOs like the Cancer Society is to create critical awareness of industry tactics, especially among stakeholders, in the media, and in decision-making. Article 5.3. of the WHO Framework Convention on Tobacco Control needs better implementation and guidelines in Finland. Outcomes: Collaborative networks both nationally, regionally and globally are bases of tobacco control advocacy. Engaging the cancer community in tobacco control is a unique role for cancer societies. What was learned: 1. Experience sharing within network structures nationally and on the Nordic, European and global level is essential for effective advocacy. 2. In the field of communication analysis of industry arguments can spur effective media strategies to support tobacco control.

Prognostic factors in patients with miliary tuberculosis

Background and purpose

Acute respiratory distress syndrome (ARDS) complication has long been considered a factor associated with poor prognosis in patients with miliary tuberculosis. However, few reports exist on the prognostic factors of miliary tuberculosis including those complicating ARDS.

Subjects and methods

We retrospectively examined prognoses and other clinical information obtained from medical records of a total of 68 patients diagnosed with miliary tuberculosis. Clinical findings were compared between patients who died within three months (non-survivor group) and those who survived beyond three months (survivor group), and risk factors for death within three months of diagnosis were examined using logistic regression analysis.

Results

Fifteen of 68 patients diagnosed with miliary tuberculosis died within three months. Most patients were aged 60 years or older (63 patients; 91.2%), with a peak in the 80 s (32 patients; 47.1%). Of the 68 patients with miliary tuberculosis, 13 (19%) had ARDS. The risk of death within three months increased with increasing age and ARDS onset during the disease course. The results of multivariate analysis revealed that, in addition to age (odd ratio (OR): 15.5) and the presence/absence of ARDS (OR: 12.0), consciousness disturbance (OR: 81.53) and high BUN levels (OR: 5.71) were independent factors for death within three months.

Conclusion

In patients with miliary tuberculosis, old age, ARDS, consciousness disturbance, and high BUN levels were factors associated with poor prognosis.

Modification of LSC spectra of 125I by high atomic number elements

The ¹²⁵I pulse-height spectra via a liquid scintillation counter (LSC) displayed notable variations. The counting efficiencies of higher and lower energy peaks increased and decreased, respectively, with the enhancement of the amount of high atomic numbered elements within the cocktails. This tendency was ascribed to the increasing probability of the interaction of photons with the scintillation cocktail. Moreover, it was noted that the shape of a ¹²⁵I spectrum strongly depends on the amount of high atomic numbered elements.

The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis

Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.

First Elastic Electron Scattering from ^{132}Xe at the SCRIT Facility

The first elastic electron scattering has been successfully performed at the self-confining radioactive-isotope ion target (SCRIT) facility, the world's first electron scattering facility for SCRIT technique achieved high luminosity (over 10^{27}  cm^{-2} s^{-1}, sufficient for determining the nuclear shape) with only 10^{8} target ions. While ^{132}Xe used in this time as a target is a stable isotope, the charge density distribution was first extracted from the momentum transfer distributions of the scattered electrons by comparing the results with those calculated by a phase shift calculation.

Prognostic value of serial serum KL-6 measurements in patients with idiopathic pulmonary fibrosis

BACKGROUND

The prognostic significance of serial measurements of serum KL-6 levels in patients with idiopathic pulmonary fibrosis (IPF) is unclear; hence, it was assessed in this study.

METHODS

Medical records of 66 patients with IPF, who were not treated with pirfenidone prior to enrollment, were retrospectively reviewed for information on clinical progress, forced vital capacity (FVC), survival, and serum KL-6 levels. We assessed initial serum levels of KL-6, serial changes in serum KL-6 levels, yearly decline in FVC (ΔFVC), and the rate of decline (%ΔFVC).

RESULTS

Patients with increased serum KL-6 levels during follow-up had a significantly steeper decline in ΔFVC than those with no KL-6 increase (-201 vs. -50.7ml/year; p=0.0001). Patients with both initial serum KL-6 ≥1000U/ml and serial increases in serum KL-6 had the steepest decline, while those with both initial serum KL-6 <1000ml and no serial increases in KL-6 had the least decline in ΔFVC and %ΔFVC. Relative to the non-increased KL-6 group, survival in the increased KL-6 group tended to be poorer (p=0.0530). Patients with both initial serum KL-6 values <1000U/ml and no serial increase in KL-6 had more favorable prognoses than those with serial increases in KL-6 or initial serum KL-6 values ≥1000U/ml (p<0.0044). Prognosis was significantly poorer in patients with serial KL-6 changes >51.8U/ml/year than in those with serial KL-6 changes <51.8U/ml/year (p=0.0009).

CONCLUSION

Thus, serial serum KL-6 measurements can be useful for assessing prognosis in patients with IPF.

Arrayed water-in-oil droplet bilayers for membrane transport analysis

The water-in-oil droplet bilayer is a simple and useful lipid bilayer system for membrane transport analysis. The droplet interface bilayer is readily formed by the contact of two water-in-oil droplets enwrapped by a phospholipid monolayer. However, the size of individual droplets with femtoliter volumes in a high-throughput manner is difficult to control, resulting in low sensitivity and throughput of membrane transport analysis. To overcome this drawback, in this study, we developed a novel micro-device in which a large number of droplet interface bilayers (>500) are formed at a time by using femtoliter-sized droplet arrays immobilized on a hydrophobic/hydrophilic substrate. The droplet volume was controllable from 3.5 to 350 fL by changing the hydrophobic/hydrophilic pattern on the device, allowing high-throughput analysis of membrane transport mechanisms including membrane permeability to solutes (e.g., ions or small molecules) with or without the aid of transport proteins. Thus, this novel platform broadens the versatility of water-in-oil droplet bilayers and will pave the way for novel analytical and pharmacological applications such as drug screening.

Treatment of vasospasm by balloon angioplasty: experimental studies and clinical experiences

The vasodilation mode and degree of the invasion caused by balloon angioplasty were experimentally examined. Assessment by light microscopy and scanning electron microscopy demonstrated that the invasion to the implanted arterial wall, taken from a patient who died from vasospasm, was minimized by the use of the balloon under the condition at 1 atm, 10 times for 10 seconds. Furthermore, we applied angioplasty to eight patients who developed severe vasospasm after subarachnoid haemorrhage, and five showed improvement in neurophysiological (transcranial Doppler sonography), neuroradiological, and clinical examinations. In addition, blood vessels obtained from one patient who died 10 days after angioplasty, demonstrated similar findings to those of the experimental studies. It can be said that angioplasty will be one of the effective therapeutic methods to manage vasospasm when it is applied under the conditions mentioned above.

Resting beta-cells - A functional reserve?

Pancreatic beta-cells play a pivotal role to synthesize and secrete insulin, as the solo source of the body. Physical as well as functional loss of beta-cells over a certain threshold result in diabetes. While the mechanisms underlying beta-cell loss in various types of diabetes have been extensively studied, less is known about residual beta-cells, found even in autoimmune type 1 diabetes and type 2 diabetes with a substantial amount. Why have these beta-cells been spared? Some patients with neonatal diabetes have demonstrated the life-changing restoration of functional beta-cells that were inactive for decades but awakened in several weeks following specific treatment. The recent striking outcomes of bariatric surgery in many obese diabetic patients indicate that their beta-cells are likely "preserved" rather than irreversibly lost even in the multifactorial polygenic state that is type 2 diabetes. Collectively, the preservation of residual beta-cells in various diabetic conditions challenges us regarding our understanding of beta-cell death and survival, where their sustenance may stem from the existence of resting beta-cells under physiological conditions. We posit that beta-cells rest and that studies of this normal feature of beta-cells could lead to new approaches for potentially reactivating and preserving beta-cell mass in order to treat diabetes.

Improved coating of pancreatic islets with regulatory T cells to create local immunosuppression by using the biotin-polyethylene glycol-succinimidyl valeric acid ester molecule

BACKGROUND

We showed that T regulatory (Treg) cells can be attached to the surface of pancreatic islets providing local immunoprotection. Further optimization of the method can improve coating efficiency, which may prolong graft survival. In this study, we compared the effectiveness of two different molecules used for binding of the Tregs to the surface of pancreatic islets. Our aim was to increase the number of Treg cells attached to islets without compromising islets viability and function.

METHODS

The cell surface of human Treg cells and pancreatic islets was modified using biotin-polyethylene glycol-N-hydroxylsuccinimide (biotin-PEG-NHS) or biotin-PEG-succinimidyl valeric acid ester (biotin-PEG-SVA). Then, islets were incubated with streptavidin as islet/Treg cells binding molecule. Treg cells were stained with CellTracker CM-DiL dye and visualized using a Laser Scanning Confocal Microscope. The number of Treg cells attached per islets surface area was analyzed by Imaris software. The effect of coating on islet functionality was determined using the glucose-stimulated insulin response (GSIR) assay.

RESULTS

The coating procedure with biotin-PEG-SVA allowed for attaching 40% more Treg cells per 1 μm(2) of islet surface. Although viability was comparable, function of the islets after coating using the biotin-PEG-SVA molecule was better preserved than with NHS molecule. GSIR was 62% higher for islets coated with biotin-PEG-SVA compared to biotin-PEG-NHS.

CONCLUSION

Coating of islets with Treg cells using biotin-PEG-SVA improves effectiveness with better preservation of the islet function. Improvement of the method of coating pancreatic islets with Treg cells could further facilitate the effectiveness of this novel immunoprotective approach and translation into clinical settings.