Usefulness of peripheral-pressure-directed balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

Background

Balloon pulmonary angioplasty (BPA) in expert center may be considered in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are technically non-operable for pulmonary endarterectomy. BPA based on objective quantitative methods has not been established. The endpoint at BPA sessions has not been clarified yet.

Objectives

The purpose of this study was to investigate the usefulness of BPA according to peripheral pressure measured by pressure wire or catheter.

Methods

This study included consecutive 143 CTEPH who underwent cardiopulmonary exercise test with right heart catheterization after BPA. All patients were divided into 2 groups such as angio-guided (n=47) group or pressure-guidedgroup (n=96). In pressure-guided group, the pulmonary arterial pressure (PAP) proximal and distal to the target lesion and the ratio of the 2 pressures were measured by the pressure wire or catheter. the endpoint was determined to when the pressure ratio of distal to proximal pressures was >0.7 to 0.8 finally. The dilation was stopped when the distal mean PAP after each dilation reached 35 mm Hg and when the baseline mean PAP was >35 mm Hg. Changes of hemodynamic parameters such as PAP and pulmonary vascular resistance (PVR) from baseline, and mean PAP and PVR at peak oxygen consumption, and pulmonary arterial pressure – cardiac output (PA-CO) slope were compared between two groups. All data except changes of hemodynamics from baseline were expressed by median [25th percentile-75th percentile]. Changes of hemodynamics from baseline were expressed by average [95% confidence interval]

Results

The median age and male were 66 [56–72] years old and 35. There were no significant differences in number of sessions and dilated vessels between two groups (Angio-guided group vs. Pressure-guided group: 4 [3–6] vs. 4 [3–5], P>0.05; 19 [12–22] vs. 17 [13–22], P>0.05). Changes of PAP and PVR from baseline in pressure-guided group was significantly higher than in angio-guided groups (Angio-guided group vs. Pressure-guided group; ΔPAP: −19 [−20 to −17] vs. −20 [−21 to −20], P>0.05; ΔPVR: −6.0 [−6.3 to −5.7] vs. −6.6 [−6.8 to −6.3], P<0.01). Mean PAP and PVR at peak oxygen consumption (VO2) and PA-CO slope in pressure-guided group were significantly lower than in angio-guided group (Angio-guided group vs. Pressure-guided group; PAP at VO2: 43 [36–50] vs. 39 [34–43], P<0.05; PVR at VO2: 2.7 [1.9–4.5] vs. 2.2 [1.6–2.9], P<0.01; PA-CO slope: 3.8 [2.1–5.2] vs. 2.9 [1.9–4.0], P<0.05).

Conclusions

Peripheral-pressure-directed BPA can improve hemodynamics at rest and exercise more effectively.

Funding Acknowledgement

Type of funding source: None

Rare SCN10A variants associated with cardiac conduction system diseases

Background

The genetic bases of cardiac conduction-system disease (CCSD) range from ion channelopathies to mutations in many other genes. Genome-wide association studies have shown common variants in SCN10A influence cardiac conduction. However, it has not yet to be determined whether vulnerability to CCSD is associated with rare coding sequence variation in the SCN10A gene.

Purpose

We sought to determine the clinical impact of rare variants in SCN10A in patients with CCSD and classified the variants according to the 2015 American College of Medical Genetics and Genomics (ACMG) standards and guidelines.

Methods

We performed screening for rare variants (minor allele frequency ≤0.001) in SCN10A in CCSD patients with an onset at a young age under 65 or those who had a family history of pacemaker implantation (PMI) (n=40; 18 female; mean age, 41±18 years). We transiently expressed engineered variants in ND 7/23 cells, and conducted whole-cell voltage clamp experiments to clarify the functional properties of the Nav1.8 current.

Results

We identified nine rare variants in SCN10A in 7 patients. Two patients were carriers of two rare variants in SCN10A and 5 were carriers of one rare variant in SCN10A. Four patients were affected with sinus node dysfunction, 1 were atrioventricular block, and 2 were both dysfunctions. We performed electrophysiological study for 8 of 9 rare variants. It demonstrated that 2 rare variants showed gain-of-function, and 3 rare variants showed loss-of-function. We finally determined 5 likely pathogenic variants in SCN10A in 5 patients (12.5%) according to the ACMG standards and guidelines. All 5 patients underwent a pacemaker implantation at an average age of 43±16.

Conclusions

These results demonstrate that SCN10A variants play a pivotal role in enhanced susceptibility of CCSD. We suggest the importance for screening SCN10A variants in clinical settings.

Funding Acknowledgement

Type of funding source: None

B-Type natriuretic peptide predicts major adverse cardiac and cerebrovascular events after catheter ablation of atrial fibrillation: insights from AF frontier ablation registry

Background

High plasma B-Type natriuretic peptide (BNP) level is associated with cardiac events or stroke in patients with atrial fibrillation (AF). However, it is still unknown whether BNP predicts worse clinical outcomes after catheter ablation ofAF.

Purpose

We aimed to see if plasma BNP level is associated with major adverse cardiac and cerebrovascular events (MACCE) after catheter ablation of AF.

Methods

We retrospectively analyzed 1,853 participants (73.1% men, mean age 63.3±10.3 years, 60.7% paroxysmal AF) who received first catheter ablation of AF with pre-ablation plasma BNP level measurement and completed follow-up more than 3 months after the procedure from AF Frontier Ablation Registry, a multicenter cohort study in Japan. We evaluated an association between plasma BNP level before catheter ablation and first MACCE in cox-regression hazard models adjusted for known risk factors. MACCE were defined as stroke/transient ischemic attack (TIA), cardiovascular events or all-cause death.

Results

The mean plasma BNP level was 120.2±3.7 pg/mL. During a mean follow-up period of 21.9 months, 57 patients (3.1%) suffered MACCE (ischemic stroke 8 [14.0%], hemorrhagic stroke 5 [8.8%], TIA 5 [8.8%], hospitalization for heart failure 11 [19.2%], acute coronary syndrome 9 [15.8%], hospitalization for other cardiovascular events 8 [14.0%] and all-cause death 11 [19.2%]). Plasma BNP level of patients with MACCE were significantly higher than those without MACCE (291.7±47.0 vs 114.7±3.42 pg/mL, P<0.001). Multivariate analysis revealed that plasma BNP level (hazard ratio [HR] per 10 pg/mL increase 1.014; 95% confidence interval [CI] 1.005–1.023; P=0.001), baseline age (HR 1.052; 95% CI 1.022–1.084; P=0.001), heart failure (HR 2.698; 95% CI 1.512–4.815; P=0.001), old myocardial infarction (HR 3.593; 95% CI 1.675–7.708; P=0.001) and non-ischemic cardiomyopathy (HR 2.676; 95% CI 1.337 - 5.355; P=0.005) were independently associated with MACCE. At receiver-operating characteristic curve analysis, plasma BNP level before catheter ablation ≥162.7 pg/mL was the best threshold to predict MACCE (area under the curve: 0.71). Kaplan-Meier curve analysis (Figure) showed that the cumulative incidence of MACCE was significantly higher in patients with a BNP ≥162.7 pg/mL than in those with a BNP below 162.7 pg/mL (HR 4.85; 95% CI 2.86–8.21; P<0.001).

Conclusions

Elevation of plasma BNP level was independently related to the increased risk of MACCE after catheter ablation ofAF.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Bristol-Meiers Squibb

Isozyme-Specific Role of SAD-A in Neuronal Migration During Development of Cerebral Cortex

SAD kinases regulate presynaptic vesicle clustering and neuronal polarization. A previous report demonstrated that Sada-/- and Sadb-/- double-mutant mice showed perinatal lethality with a severe defect in axon/dendrite differentiation, but their single mutants did not. These results indicated that they were functionally redundant. Surprisingly, we show that on a C57BL/6N background, SAD-A is essential for cortical development whereas SAD-B is dispensable. Sada-/- mice died within a few days after birth. Their cortical lamination pattern was disorganized and radial migration of cortical neurons was perturbed. Birth date analyses with BrdU and in utero electroporation using pCAG-EGFP vector showed a delayed migration of cortical neurons to the pial surface in Sada-/- mice. Time-lapse imaging of these mice confirmed slow migration velocity in the cortical plate. While the neurites of hippocampal neurons in Sada-/- mice could ultimately differentiate in culture to form axons and dendrites, the average length of their axons was shorter than that of the wild type. Thus, analysis on a different genetic background than that used initially revealed a nonredundant role for SAD-A in neuronal migration and differentiation.

A synthetic synaptic organizer protein restores glutamatergic neuronal circuits

Neuronal synapses undergo structural and functional changes throughout life, which are essential for nervous system physiology. However, these changes may also perturb the excitatory-inhibitory neurotransmission balance and trigger neuropsychiatric and neurological disorders. Molecular tools to restore this balance are highly desirable. Here, we designed and characterized CPTX, a synthetic synaptic organizer combining structural elements from cerebellin-1 and neuronal pentraxin-1. CPTX can interact with presynaptic neurexins and postsynaptic AMPA-type ionotropic glutamate receptors and induced the formation of excitatory synapses both in vitro and in vivo. CPTX restored synaptic functions, motor coordination, spatial and contextual memories, and locomotion in mouse models for cerebellar ataxia, Alzheimer's disease, and spinal cord injury, respectively. Thus, CPTX represents a prototype for structure-guided biologics that can efficiently repair or remodel neuronal circuits.

Chondroitin sulfate N-acetylgalactosyltransferase-1 knockout shows milder phenotype in experimental autoimmune encephalomyelitis than in wild type

Proteoglycans (PGs) are one of the main components in the extracellular matrix of the central nervous system. Chondroitin sulfate (CS) is a glycosaminoglycan (GAG), which is composed of major PGs. Similar to keratin sulfate (KS), another GAG, CS inhibits axon regeneration. However, the influence of these GAGs on the pathogenicity of neuroimmunological diseases is unclear. Here, we induced experimental autoimmune encephalomyelitis (EAE) in mice lacking CS N-acetylgalactosaminyltransferase-1 (CSGalNAcT1-KO), an important enzyme for CS synthesis. In our study, CSGalNAcT1-KO mice showed milder EAE symptoms than those in wild-type (WT) mice. The recall response of antigen-specific lymphocytes showed that CSGalNAcT1-KO-derived lymphocytes had a milder cell proliferation response than that in WT-derived lymphocytes. These results suggest that CS contributes toward the induction phase of EAE. We previously performed EAE experiments in GlcNAc-6-O-sulfotransferase KO (GlcNAc6ST-KO) and C6ST1-KO mice, which had reduced KS and reduced CS-C, respectively. EAE in CSGalNAcT1-KO mice was more similar to that in GlcNAc6ST-KO mice than in C6ST1-KO mice. In conclusion, the distinct GAG sugar chains are associated with severe or mild phenotypes of EAE and are therefore potential new therapeutic targets for neuroimmunological diseases, including multiple sclerosis.

P628Association of outpatient cardiac rehabilitation with mortality and morbidities in patients with acute myocardial infarction

Background/Introduction

Outpatient cardiac rehabilitation (CR) is commonly recommended for patients with acute myocardial infarction (AMI). However, the survival benefit has recently been contested, especially with no survival benefit having been found in non-Western countries.

Purpose

To investigate whether outpatient CR, under current real-world clinical practice, is associated with lower mortality and morbidity risks in patients with AMI.

Methods

The retrospective cohort study was conducted from January 2011 to June 2016 (final date of follow-up: July 31, 2016) with a nation-wide administrative database for acute-care hospitals in Japan. Data for 7,411 patients were analyzed, with 5,654 fulfilling the inclusion criteria of being admitted for AMI and receiving both percutaneous coronary intervention and inpatient CR between January 2011 and December 2014. We compared patients who participated in outpatient CR at least once within 180 days of discharge and who did not. To account for measured baseline imbalances between outpatient CR participants and non-participants, 1:1 propensity-score matching was performed. The primary outcome was a composite of all-cause death and recurrence of AMI after the landmark time-point of day 180 after discharge. Secondary outcomes included all-cause death, recurrence of AMI, and heart failure.

Results

Among 5,654 patients (mean [SD] age, 66.8 [12.4] years; 21.2% female; median follow-up period [IQR] 1.44 [0.87 to 2.27] years), 730 (12.9%) received outpatient CR. Of 1,458 propensity-score matched patients, outpatient CR participants did not show a significantly lower risk of the primary outcome than non-participants (1.38 vs. 2.12 per 100 patient-years; hazard ratio [HR], 0.71 [95% CI, 0.32 to 1.61]). Similarly, outpatient CR participation was not associated with lower risks of all-cause death (0.68 vs. 1.31 per 100 patient-years; HR, 0.83 [95% CI, 0.25 to 2.73]), recurrence of AMI (0.69 vs. 0.88 per 100 patient-years; HR, 0.56 [95% CI, 0.19 to 1.66]) or heart failure (2.01 vs. 2.06 per 100 patient-years; HR, 0.89 [95% CI, 0.47 to 1.72]), respectively.

Conclusion

Among patients with AMI who received percutaneous coronary intervention and inpatient CR, outpatient CR was not associated with lower risks of mortality and morbidities. The survival benefit of outpatient CR should be reaffirmed under current real-world clinical practice, especially in non-Western countries.

Periodontitis Is Associated with Chronic Obstructive Pulmonary Disease

Although they are known to share pathophysiological processes, the relationship between periodontitis and chronic obstructive pulmonary disease (COPD) is not fully understood. The aim of the present study was to test the hypothesis that periodontitis is associated with a greater risk of development of COPD, when smoking is taken into account. The analysis in a 5-y follow-up population-based cohort study was based on 900 community-dwelling Japanese adults (age: 68.8 ± 6.3 [mean ± SD], 46.0% male) without COPD aged 60 or older with at least 1 tooth. Participants were classified into 3 categories according to baseline periodontitis severity (no/mild, moderate, and severe). COPD was spirometrically determined by a fixed ratio of <0.7 for forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and by FEV1/FVC below the lower limit of normal. Poisson regression was used to calculate the relative risk (RR) of developing COPD according to the severity of periodontitis. The population attributable fraction (PAF) was also calculated. During follow-up, 22 (2.4%) subjects developed COPD. Compared with no/mild periodontitis subjects, a significantly increased risk of COPD occurred among severe periodontitis subjects (RR = 3.55; 95% confidence interval [CI], 1.18 to 10.67), but no significant differences were observed between the no/mild and moderate categories (RR = 1.48; 95% CI, 0.56 to 3.90). After adjustment for potential confounders, including smoking intensity, the relationship between severe periodontitis and risk of COPD remained significant (RR = 3.51; 95% CI, 1.15 to 10.74). Likewise, there was a positive association of periodontitis severity with risk of COPD ( P for trend = 0.043). The PAF for COPD due to periodontitis was 22.6%. These data highlight the potential importance of periodontitis as a risk factor for COPD.

Abstract P3-06-04: Clonal evolution of non-malignant proliferative lesions into breast cancers

[Introduction] Non-malignant proliferative lesions in the breast have been implicated in the development of invasive breast cancer. Previous studies showed that adjacent atypical proliferative lesions and breast cancers shared common genetic alterations, suggesting that these evolved from the same ancestral cell. However, the clonal structure of atypical proliferative lesions and their clonal dynamics during progression to cancer are poorly understood. In this study, we compared genetic profiles (with and without pathogenic germline mutations) of normal mammary ducts, non-malignant proliferative lesions, and cancer tissues from the same patients to illustrate the clonal evolution of cancer from a non-malignant epithelial cell.

[Methods] Multiple samples were collected from different proliferative lesions within the cancer-borne breast, including invasive cancers, using micro-dissection from formalin-fixed, paraffin-embedded surgical specimens. Somatic mutations and copy number alterations (CNAs) were then evaluated by whole exome sequencing.

[Results] We analyzed a total of 34 samples from 5 premenopausal females carrying estrogen receptor-positive cancers, where the samples were obtained from normal ducts (N = 6), non-atypical (N = 1) and atypical (N = 8) proliferative lesions, and non-invasive (N = 16) and invasive (N = 3) cancers. The number of somatic mutations per sample ranged from 1 to 276 and increased with disease progression, regardless of the germline mutation status. Two cases with bilateral cancers had a pathogenic germline mutation of either BRCA2 or TP53, where no somatic mutations or CNAs were shared by individual proliferative lesions, suggesting multifocal independent cancerous evolutions. By contrast, in the remaining three unilateral cases, no pathogenic germline mutations were detected, but all proliferative lesions, which were separated by a distance of 7-25 mm, shared one or more driver alterations, such as an AKT1 mutation (UID: KU01), concurrent 1q gain and 16q loss (der(1;16)) (UID: KU02), and a GATA3 mutation and der(1;16) (UID: KU03), while harboring private mutations and/or CNAs of their own. The phylogenetic analysis based on the number of shared mutations predicted an early origin of these founder mutations, which frequently predated decades before the onset of cancer.

[Conclusions] Our results suggest that early breast cancer development is shaped by the evolution of multiple precancerous clones. These clones are originated from a common ancestor that acquired a founder mutation long before the onset of cancer, followed by branching evolution of multiple clones that acquired additional driver mutations of their own, from which an invasive cancer ultimately develops. In hereditary cases, this process is thought to be substantially promoted multi-focally from within the entire breasts by a germline mutation shared by all mammary cells, frequently resulting in bilateral and/or multifocal breast cancers. Our findings provide unique insight into the early development of breast cancer.

Citation Format: Nishimura T, Yoshida K, Kawata Y, Takeuchi Y, Kakiuchi N, Shiozawa Y, Aoki K, Hirata M, Kataoka TR, Sakurai T, Baba S, Shiraishi Y, Chiba K, Takeuchi K, Haga H, Miyano S, Toi M, Ogawa S. Clonal evolution of non-malignant proliferative lesions into breast cancers [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-06-04.

Adhesive Platelet Count and Blood Coagulability in Myocardial Infarction and Cerebral Thrombosis

In 382 patients, aged 21 to 76 years, including 39 healthy volunteers, a platelet count by Olef’s method, an adhesive platelet count by Moolten-Vroman’s method, prothrombin activity due to one-stage prothrombin time and calcium clotting time were measured. In 39 cases of myocardial infarction and 40 cases of cerebral thrombosis, both in acute stage, a marked decrease in the adhesive platelet count and adhesive index and an increase of prothrombin activity were observed with statistical significance compared to the healthy group (P < 0.01). In the recovery stage of myocardial infarction, cerebral thrombosis and other diseases, except for malignant tumors, acute infectious diseases, diabetes mellitus and blood or liver diseases, the above observations were absent or reduced. In the case of thrombosis, a negative correlation was seen between the adhesive platelet count and prothrombin activity (r — —0.238, P < 0.01). There is no correlation between the changes in platelet adhesiveness or blood coagulability and total cholesterol level in serum.

Appearance of Thrombogenic Tendency Induced by Adrenaline and Its Prevention by β-Adrenergic Blocking Agent, Nialamide and Pyridinolcarbamate

In 52 men and 33 women, the total, adhesive and nonadhesive platelet counts, onestage prothrombin time, euglobulinlysis time, and plasma nonesterified fatty acid were measured before and after an intravenous injection with 0.1 μg/kg of adrenaline or 1-noradrenaline. Three hours before the injection, placebo, 30 mg of phenoxybenzamine, 300 mg of pronethalol, 100 mg of nialamide or 100 mg of pyridinolcarbamate was administered orally under the double blind technique. Five minutes after the injection with adrenaline in 15 cases pretreated with placebo, a decrease in adhesive platelet count, and a shortening of one-stage prothrombin time and euglobulin lysis time were observed with statistical significance (P ˂ 0.01 ∼ 0.05). These changes were not observed in 15 cases injected with saline or noradrenaline. The changes were not observed in 10 cases pretreated with pronethalol, but were observed in 10 cases pretreated with phenoxybenzamine. So the effect of adrenaline may be due to stimulation of ß-adrenergic receptor sites. Meanwhile, the decrease in adhesive platelet count and the enhancement of blood coagulability were prevented by nialamide and pyridinolcarbamate, while the enhancement of fibrinolysis was not. The preventive effect of nialamide was less than that of pyridinolcarbamate. Phenoxybenzamine and nialamide prevented an increase in systolic blood pressure induced by adrenaline, and pronethalol prevented tachycardia by adrenaline, while pyridinolcarbamate did not affect these changes. Changes in plasma nonesterified fatty acid showed no relationship to the above hematological changes.

Growth Cone Phosphoproteomics Reveals that GAP-43 Phosphorylated by JNK Is a Marker of Axon Growth and Regeneration

Neuronal growth cones are essential for nerve growth and regeneration, as well as for the formation and rearrangement of the neural network. To elucidate phosphorylation-dependent signaling pathways and establish useful molecular markers for axon growth and regeneration, we performed a phosphoproteomics study of mammalian growth cones, which identified >30,000 phosphopeptides of ∼1,200 proteins. The phosphorylation sites were highly proline directed and primarily MAPK dependent, owing to the activation of JNK, suggesting that proteins that undergo proline-directed phosphorylation mediate nerve growth in the mammalian brain. Bioinformatics analysis revealed that phosphoproteins were enriched in microtubules and the cortical cytoskeleton. The most frequently phosphorylated site was S96 of GAP-43 (growth-associated protein 43-kDa), a vertebrate-specific protein involved in axon growth. This previously uncharacterized phosphorylation site was JNK dependent. S96 phosphorylation was specifically detected in growing and regenerating axons as the most frequent target of JNK signaling; thus it represents a promising new molecular marker for mammalian axonal growth and regeneration.

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Phosphoproteomics of mammalian growth cone membranes reveals activation of MAPK

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JNK is the activated MAPK in growth cones and phosphorylates S96 of GAP-43

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pS96 of GAP-43, the most frequent site, is observed in growing axons

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pS96 is biochemically detected in the regenerating axons of the peripheral nerves

Robust water desalination membranes against degradation using high loads of carbon nanotubes

Chlorine resistant reverse osmosis (RO) membranes were fabricated using a multi-walled carbon nanotube-polyamide (MWCNT-PA) nanocomposite. The separation performance of these membranes after chlorine exposure (4800 ppm·h) remained unchanged (99.9%) but was drastically reduced to 82% in the absence of MWCNT. It was observed that the surface roughness of the membranes changed significantly by adding MWCNT. Moreover, membranes containing MWCNT fractions above 12.5 wt.% clearly improved degradation resistance against chlorine exposure, with an increase in water flux while maintaining salt rejection performance. Molecular dynamics and quantum chemical calculations were performed in order to understand the high chemical stability of the MWCNT-PA nanocomposite membranes, and revealed that high activation energies are required for the chlorination of PA. The results presented here confirm the unique potential of carbon nanomaterials embedded in polymeric composite membranes for efficient RO water desalination technologies.

Roles of CSGalNAcT1, a key enzyme in regulation of CS synthesis, in neuronal regeneration and plasticity

Chondroitin sulfate (CS) is a sulfated glycosaminoglycan composed of a long chain of repeating disaccharide units that are attached to core proteins, resulting in CS proteoglycans (CSPGs). In the mature brain, CS is concentrated in perineuronal nets (PNNs), which are extracellular structures that surround synapses and regulate synaptic plasticity. In addition, CS is rapidly synthesized after CNS injury to create a physical and chemical barrier that inhibits axon growth. Most previous studies used a bacterial CS-degrading enzyme to investigate the physiological roles of CS. Recent studies have shown that CS is synthesized by more than 15 enzymes, all of which have been characterized in vitro. Here we focus on one of those enzymes, CSGalNAcT1 (T1). We produced T1 knockout mice (KO), which show extensive axon regeneration following spinal cord injury, as well as the loss of onset of ocular dominance plasticity. These results from T1KO mice suggest important roles for extracellular CS in the brain regarding neuronal plasticity and axon regeneration.

Abnormalities in perineuronal nets and behavior in mice lacking CSGalNAcT1, a key enzyme in chondroitin sulfate synthesis

Chondroitin sulfate (CS) is an important glycosaminoglycan and is mainly found in the extracellular matrix as CS proteoglycans. In the brain, CS proteoglycans are highly concentrated in perineuronal nets (PNNs), which surround synapses and modulate their functions. To investigate the importance of CS, we produced and precisely examined mice that were deficient in the CS synthesizing enzyme, CSGalNAcT1 (T1KO). Biochemical analysis of T1KO revealed that loss of this enzyme reduced the amount of CS by approximately 50% in various brain regions. The amount of CS in PNNs was also diminished in T1KO compared to wild-type mice, although the amount of a major CS proteoglycan core protein, aggrecan, was not changed. In T1KO, we observed abnormalities in several behavioral tests, including the open-field test, acoustic startle response, and social preference. These results suggest that T1 is important for plasticity, probably due to regulation of CS-dependent PNNs, and that T1KO is a good model for investigation of PNNs.