F-type proton-pumping ATPase mediates acid tolerance in Streptococcus mutans.

AIMS: Streptococcus mutans is highly sensitive to inhibitors of proton-pumping F-type ATPase (F-ATPase) under acidic conditions. Herein, we investigated the role of S. mutans F-ATPase in acid tolerance using a bacterium expressing the F-ATPase ß subunit at lower levels than the wild-type strain. METHODS AND RESULTS: We generated a mutant S. mutans expressing the catalytic ß subunit of F-ATPase at lower levels than the wild-type bacterium. The mutant cells exhibited a significantly slower growth rate at pH 5.30, whereas the rate was essentially the same as that of wild-type cells at pH 7.40. In addition, the colony-forming ability of the mutant was decreased at pH <4.30 but not at pH 7.40. Thus, the growth rate and survival of S. mutans expressing low levels of the ß subunit were reduced under acidic conditions. CONCLUSIONS: Together with our previous observations, this study indicates that F-ATPase is involved in the acid tolerance mechanism of S. mutans by secreting protons from the cytoplasm.

Efficient scarless genome editing in human pluripotent stem cells.

Scarless genome editing in human pluripotent stem cells (hPSCs) represents a goal for both precise research applications and clinical translation of hPSC-derived therapies. Here we established a versatile and efficient method that combines CRISPR-Cas9-mediated homologous recombination with positive-negative selection of edited clones to generate scarless genetic changes in hPSCs.

Knockdown of the mitochondria-localized protein p13 protects against experimental parkinsonism.

Mitochondrial dysfunction in the nigrostriatal dopaminergic system is a critical hallmark of Parkinson's disease (PD). Mitochondrial toxins produce cellular and behavioural dysfunctions resembling those in patients with PD Causative gene products for familial PD play important roles in mitochondrial function. Therefore, targeting proteins that regulate mitochondrial integrity could provide convincing strategies for PD therapeutics. We have recently identified a novel 13-kDa protein (p13) that may be involved in mitochondrial oxidative phosphorylation. In the current study, we examine the mitochondrial function of p13 and its involvement in PD pathogenesis using mitochondrial toxin-induced PD models. We show that p13 overexpression induces mitochondrial dysfunction and apoptosis. p13 knockdown attenuates toxin-induced mitochondrial dysfunction and apoptosis in dopaminergic SH-SY5Y cells via the regulation of complex I. Importantly, we generate p13-deficient mice using the CRISPR/Cas9 system and observe that heterozygous p13 knockout prevents toxin-induced motor deficits and the loss of dopaminergic neurons in the substantia nigra. Taken together, our results suggest that manipulating p13 expression may be a promising avenue for therapeutic intervention in PD.

p13 overexpression in pancreatic ß-cells ameliorates type 2 diabetes in high-fat-fed mice.

We examined the pancreatic function of p13 encoded by 1110001J03Rik, whose expression is decreased in pancreatic islets in high-fat-fed diabetic mice, by generating transgenic mice overexpressing p13 (p13-Tg) in pancreatic ß-cells. p13-Tg mice showed normal basal glucose metabolism; however, under high-fat feeding, these animals showed augmented glucose-induced first-phase and total insulin secretion, improved glucose disposal, greater islet area and increased mitotic insulin-positive cells. In addition, high-fat diet-induced 4-hydroxynonenal immunoreactivity, a reliable marker and causative agent of lipid peroxidative stress, was significantly decreased in p13-Tg mouse islets. These results indicate that p13 is a novel pancreatic factor exerting multiple beneficial effects against type 2 diabetes.

Role of complement 3a in the growth of mesangial cells from stroke-prone spontaneously hypertensive rats.

Vascular smooth muscle cells (VSMCs) derived from spontaneously hypertensive rats (SHR) show exaggerated growth with a synthetic phenotype and angiotensin II (Ang II) production associated with increased production of complement (C3). We hypothesized that C3 is involved in the growth of mesangial cells (MCs) from hypertensive rats. We examined the effects of a C3a receptor inhibitor on proliferation, phenotype and Ang II generation in MCs from stroke prone-spontaneously hypertensive rats (SHR)-SP, SHR and Wistar-Kyoto (WKY) rats. Expression of C3 and C3a receptor were evaluated by immunohistochemical staining of the renal cortex. We examined the effects of the C3a inhibitor, SB290157, on proliferation, the expression of phenotype-marker mRNAs and Ang II production in cells from SHR-SP, SHR and WKY rats. Immunostaining of C3 was stronger in SHR and SHRSP glomeruli. MCs from SHR-SP and SHR abundantly express pre-pro C3 mRNA. SB290157 significantly inhibited basal DNA synthesis and proliferation of MCs from SHR-SP and SHR. Expression of osteopontin mRNA in MCs from SHR-SP and SHR was decreased with SB290157 treatment, whereas MC basal expression of α-SMA mRNA was decreased. SB290157 significantly decreased the production of Ang II in MCs from SHR-SP and SHR. Endogenous C3a promotes exaggerated growth with a synthetic phenotype and the production of Ang II in MCs from SHR-SP and SHR. The C3 and C3a receptor system may primarily be involved in the pathogenesis of renal remodeling in hypertensive rats.

iPSC-derived hypoimmunogenic tissue resident memory T cells mediate robust anti-tumor activity against cervical cancer.

Functionally rejuvenated human papilloma virus-specific cytotoxic T lymphocytes (HPV-rejTs) generated from induced pluripotent stem cells robustly suppress cervical cancer. However, autologous rejT generation is time consuming, leading to difficulty in treating patients with advanced cancer. Although use of allogeneic HPV-rejTs can obviate this, the major obstacle is rejection by the patient immune system. To overcome this, we develop HLA-A24&-E dual integrated HPV-rejTs after erasing HLA class I antigens. These rejTs effectively suppress recipient immune rejection while maintaining more robust cytotoxicity than original cytotoxic T lymphocytes. Single-cell RNA sequencing performed to gain deeper insights reveal that HPV-rejTs are highly enriched with tissue resident memory T cells, which enhance cytotoxicity against cervical cancer through TGFßR signaling, with increased CD103 expression. Genes associated with the immunological synapse also are upregulated, suggesting that these features promote stronger activation of T cell receptor (TCR) and increased TCR-mediated target cell death. We believe that our work will contribute to feasible "off-the-shelf" T cell therapy with robust anti-cervical cancer effects.

Characterization of insulin adsorption behavior of dialyzer membranes used in hemodialysis.

Although it has been reported that plasma insulin is removed by hemodialysis (HD), the mechanism for this has not been elucidated. We investigated the mechanism of insulin removal during HD treatment and the characteristics of insulin removal with three high-flux membranes. In our in vivo study, 20 stable diabetic patients on HD were randomly selected for three HD sessions with three different membranes: polysulfone (PS), cellulose triacetate (CTA), and polyester polymer alloy (PEPA). Blood samples were obtained from the blood tubing at the arterial (A) site at the beginning and end of the sixth HD session to investigate insulin reduction in patients. At 1 h after the initiation of dialysis, blood samples were obtained from both the A and venous sites of the dialyzer to investigate the insulin clearance with the different membranes. There was a significant reduction in patients' plasma insulin at each time point with each of the three membranes. The insulin clearance with the PS membrane was significantly higher than that with the CTA and PEPA membranes. Although no difference was observed in the plasma insulin reduction rate between the three membranes in the total subject group, there was a significantly higher reduction rate with the PS membrane in insulin-dependent diabetes mellitus subjects. The clearance of insulin in in vitro tests was significantly higher with the PS and PEPA membranes than with the CTA membrane in both new and clinically used dialyzers. Insulin was not detected in the dialysate or ultrafiltration fluids in either the in vivo or in vitro studies. The mechanism of plasma insulin clearance by HD is mainly by adsorption, and the amount of insulin adsorbed differed depending on the dialyzer membrane used.

Comparison of sustained hemodiafiltration with continuous venovenous hemodiafiltration for the treatment of critically ill patients with acute kidney injury.

Despite improvements in medical care, the mortality of critically ill patients with acute kidney injury (AKI) who require renal replacement therapy (RRT) remains high. We describe a new approach, sustained hemodiafiltration, to treat patients who suffered from acute kidney injury and were admitted to intensive care units (ICUs). In our study, 60 critically ill patients with AKI who required RRT were treated with either continuous venovenous hemodiafiltration (CVVHDF) or sustained hemodiafiltration (S-HDF). The former was performed by administering a postfilter replacement fluid at an effluent rate of 35 mL/kg/h, and the latter was performed by administering a postfilter replacement fluid at a dialysate-flow rate of 300-500 mL/min. The S-HDF was delivered on a daily basis. The baseline characteristics of the patients in the two treatment groups were similar. The primary study outcome--survival until discharge from the ICU or survival for 30 days, whichever was earlier--did not significantly differ between the two groups: 70% after CVVHDF and 87% after S-HDF. The hospital-survival rate after CVVHDF was 63% and that after S-HDF was 83% (P < 0.05). The number of patients who showed renal recovery at the time of discharge from the ICU and the hospital and the duration of the ICU stay significantly differed between the two treatments (P < 0.05). Although there was no significant difference between the mean number of treatments performed per patient, the mean duration of daily treatment in the S-HDF group was 6.5 +/- 1.0 h, which was significantly shorter. Although the total convective volumes--the sum of the replacement-fluid and fluid-removal volumes--did not differ significantly, the dialysate-flow rate was higher in the S-HDF group. Our results suggest that in comparison with conventional continuous RRT, including high-dose CVVHDF, more intensive renal support in the form of postdilution S-HDF will decrease the mortality and accelerate renal recovery in critically ill patients with AKI.

Generation of human striatal organoids and cortico-striatal assembloids from human pluripotent stem cells.

Cortico-striatal projections are critical components of forebrain circuitry that regulate motivated behaviors. To enable the study of the human cortico-striatal pathway and how its dysfunction leads to neuropsychiatric disease, we developed a method to convert human pluripotent stem cells into region-specific brain organoids that resemble the developing human striatum and include electrically active medium spiny neurons. We then assembled these organoids with cerebral cortical organoids in three-dimensional cultures to form cortico-striatal assembloids. Using viral tracing and functional assays in intact or sliced assembloids, we show that cortical neurons send axonal projections into striatal organoids and form synaptic connections. Medium spiny neurons mature electrophysiologically following assembly and display calcium activity after optogenetic stimulation of cortical neurons. Moreover, we derive cortico-striatal assembloids from patients with a neurodevelopmental disorder caused by a deletion on chromosome 22q13.3 and capture disease-associated defects in calcium activity, showing that this approach will allow investigation of the development and functional assembly of cortico-striatal connectivity using patient-derived cells.

Loss of Extreme Long-Range Enhancers in Human Neural Crest Drives a Craniofacial Disorder.

Non-coding mutations at the far end of a large gene desert surrounding the SOX9 gene result in a human craniofacial disorder called Pierre Robin sequence (PRS). Leveraging a human stem cell differentiation model, we identify two clusters of enhancers within the PRS-associated region that regulate SOX9 expression during a restricted window of facial progenitor development at distances up to 1.45 Mb. Enhancers within the 1.45 Mb cluster exhibit highly synergistic activity that is dependent on the Coordinator motif. Using mouse models, we demonstrate that PRS phenotypic specificity arises from the convergence of two mechanisms: confinement of Sox9 dosage perturbation to developing facial structures through context-specific enhancer activity and heightened sensitivity of the lower jaw to Sox9 expression reduction. Overall, we characterize the longest-range human enhancers involved in congenital malformations, directly demonstrate that PRS is an enhanceropathy, and illustrate how small changes in gene expression can lead to morphological variation.

Neuronal defects in a human cellular model of 22q11.2 deletion syndrome.

22q11.2 deletion syndrome (22q11DS) is a highly penetrant and common genetic cause of neuropsychiatric disease. Here we generated induced pluripotent stem cells from 15 individuals with 22q11DS and 15 control individuals and differentiated them into three-dimensional (3D) cerebral cortical organoids. Transcriptional profiling across 100 days showed high reliability of differentiation and revealed changes in neuronal excitability-related genes. Using electrophysiology and live imaging, we identified defects in spontaneous neuronal activity and calcium signaling in both organoid- and 2D-derived cortical neurons. The calcium deficit was related to resting membrane potential changes that led to abnormal inactivation of voltage-gated calcium channels. Heterozygous loss of DGCR8 recapitulated the excitability and calcium phenotypes and its overexpression rescued these defects. Moreover, the 22q11DS calcium abnormality could also be restored by application of antipsychotics. Taken together, our study illustrates how stem cell derived models can be used to uncover and rescue cellular phenotypes associated with genetic forms of neuropsychiatric disease.

[Longstanding intractable massive ascites caused by chronic lupus peritonitis with nephrotic syndrome: a case report].

A 36-year-old woman with systemic lupus erythematosus (SLE) and nephrotic syndrome showed massive ascites. She was admitted to our hospital because of edema in both legs and a remarkably distended non-tender abdomen. On admission, massive ascites was observed in the abdominal CT scan findings. Laboratory examination of the ascites showed low levels of total protein (1.5 g/dL), albumin (0.5 g/dL) and LDH (89 IU/L), which were characterized as ascites per diapedesis. In addition, she was diagnosed with SLE and nephrotic syndrome from the clinical and laboratory findings. We treated her with steroid therapy, including methylprednisolone plus therapy. Although the serological abnormalities with SLE had normalized and urinary protein almost disappeared on the 51th hospital day, the ascites had not improved at all. These findings indicated that she had suffered from chronic lupus peritonitis, complicated with nephrotic syndrome and we had continued to treat her with prednisolone for a long time. The ascites was remarkably diminished at 220 days after admission. We believe that in addition to nephrotic syndrome, impaired vascular circulation caused by chronic lupus peritonitis might have contributed to accumulation of the massive ascites.

Highly Efficient and Marker-free Genome Editing of Human Pluripotent Stem Cells by CRISPR-Cas9 RNP and AAV6 Donor-Mediated Homologous Recombination.

Genome editing of human pluripotent stem cells (hPSCs) provides powerful opportunities for in vitro disease modeling, drug discovery, and personalized stem cell-based therapeutics. Currently, only small edits can be engineered with high frequency, while larger modifications suffer from low efficiency and a resultant need for selection markers. Here, we describe marker-free genome editing in hPSCs using Cas9 ribonucleoproteins (RNPs) in combination with AAV6-mediated DNA repair template delivery. We report highly efficient and bi-allelic integration frequencies across multiple loci and hPSC lines, achieving mono-allelic editing frequencies of up to 94% at the HBB locus. Using this method, we show robust bi-allelic correction of homozygous sickle cell mutations in a patient-derived induced PSC (iPSC) line. Thus, this strategy shows significant utility for generating hPSCs with large gene integrations and/or single-nucleotide changes at high frequency and without the need for introducing selection genes, enhancing the applicability of hPSC editing for research and translational uses.

A long-forgotten 'dinosaur' bone from a museum cabinet, uncovered to be a Japan's iconic extinct mammal, Paleoparadoxia (Desmostylia, Mammalia).

Here, we report a new 'discovery' of a desmostylian fossil in the geological collection at a national university in Japan. This fossil was unearthed over 60 years ago and donated to the university. Owing to the original hand-written note kept with the fossil in combination with interview investigation, we were able to reach two equally possible fossil sites in the town of Tsuchiyu Onsen, Fukushima. Through the interviews, we learned that the fossil was discovered during construction of a debris flow barrier and that it was recognized as a 'dinosaur' bone among the locals and displayed in the Village Hall before/until the town experienced a fire disaster in 1954. As scientific findings, the fossil was identified to be a right femur of Paleoparadoxia (Desmostylia), which shows well-preserved muscle scars on the surface. The age was estimated to be 15.9 Ma or younger in zircon-dating. This study shows an excellent case that historical and scientific significances could be extracted from long-forgotten uncatalogued specimens as long as the original information is retained with the specimens.

Comparative gene expression profiles in pancreatic islets associated with agouti yellow mutation and PACAP overexpression in mice.

In diabetes mellitus, pituitary adenylate cyclase-activating polypeptide (PACAP) has insulinotropic and glucose-lowering properties. We previously demonstrated that transgenic mice overexpressing PACAP in pancreatic ß-cells (PACAP-Tg) show attenuated pancreatic islet hyperplasia and hyperinsulinemia in type 2 diabetic models. To explore the underlying mechanisms, here we crossed PACAP-Tg mice with lethal yellow agouti (KKAy) diabetic mice, and performed gene chip analysis of laser capture microdissected pancreatic islets from four F1 offspring genotypes (wild-type, PACAP-Tg, KKAy, and PACAP-Tg:KKAy). We identified 1371 probes with >16-fold differences between at least one pair of genotypes, and classified the probes into five clusters with characteristic expression patterns. Gene ontology enrichment analysis showed that genes involved in the terms ribosome and intracellular organelles such as ribonucleoprotein complex, mitochondrion, and chromosome organization were significantly enriched in clusters characterized by up-regulated genes in PACAP-Tg:KKAy mice compared with KKAy mice. These results may provide insight into the mechanisms of diabetes that accompany islet hyperplasia and amelioration by PACAP.

Role of complement 3a in the synthetic phenotype and angiotensin II-production in vascular smooth muscle cells from spontaneously hypertensive rats.

BACKGROUND: Spontaneously hypertensive rats (SHR)-derived vascular smooth muscle cells (VSMCs) show exaggerated growth with a synthetic phenotype and angiotensin II (Ang II)-production. To evaluate the contribution of complement 3 (C3) or C3a toward these abnormalities in SHR, we examined effects of a C3a receptor inhibitor on proliferation, phenotype, and Ang II-production in VSMCs from SHR and Wistar-Kyoto (WKY) rats. METHODS: Expression of pre-pro-C3 messenger RNA (mRNA) and C3 protein was evaluated by reverse transcription-PCR and western blot analyses, and C3a receptor mRNA was evaluated by reverse transcription-PCR analysis in quiescent VSMCs from SHR and WKY rats. We examined the effects of the C3a inhibitor, SB290157, on proliferation and the expression of phenotype-marker and Krueppel-like factor 5 (KLF-5) mRNAs in VSMCs from SHR and WKY rats. We examined effects of C3a receptor inhibitor, SB290157, on Ang II-production in conditioned medium of VSMCs from SHR and WKY rats by a radioimmunoassay. RESULTS: Expression of pre-pro-C3 mRNA and C3 protein was significantly higher in SHR VSMCs than WKY VSMCs. SB290157 significantly inhibited proliferation of VSMCs from SHR, but not in cells from WKY rats. Relative to WKY VSMCs, SB290157 significantly increased the low expression of SM22α mRNA and decreased the high expression of osteopontin mRNA in SHR VSMCs. SB290157 significantly decreased the high expression of KLF-5 and Ang II-production in VSMCs from SHR, but not in cells from WKY rats. CONCLUSIONS: C3a induces exaggerated growth, a synthetic phenotype and Ang II-production in SHR-derived VSMCs. C3a may be primarily involved in cardiovascular remodeling in hypertension.

Cerulein-induced acute pancreatitis in PACAP knockout mice.

In our previous study, we reported that cerulein-induced acute pancreatitis is aggravated in pancreatic ß-cell-specific pituitary adenylate cyclase-activating polypeptide (PACAP) transgenic mice, showing that an increase in pancreatic PACAP is a risk factor for progression of acute pancreatitis. Accordingly, in this study, we examined the progression of cerulein-induced acute pancreatitis in PACAP knockout (KO) mice. Unexpectedly, after cerulein, about 60% of the KO mice showed severe hypothermia below 30°C by 12 h and most of them died within 72 h. In contrast, the remaining KO and wild-type mice showed normothermia with no mortality. Thus, KO mice could be classified into two groups as hypothermic (HT-KO) and normothermic (NT-KO) to cerulein. Only HT-KO mice subsequently showed severe mortality, although both HT-KO and NT-KO mice exhibited similar susceptibility of lungs to cerulein toxicity, comparable to that in wild-type mice. Regarding pancreatitis, HT-KO mice showed ameliorated pancreatic damage without any rise in serum enzyme activities, whereas NT-KO mice exhibited a similar degree of pancreatitis to wild-type mice. Taken together, the present results indicate that lack of pancreatic PACAP did not aggravate, but rather ameliorated, cerulein-induced pancreatitis. In addition, about half of KO mice showed a novel phenotype in which cerulein caused rapid and severe hypothermia, followed by death.

Over-expression of pancreatic pituitary adenylate cyclase-activating polypeptide (PACAP) aggravates cerulein-induced acute pancreatitis in mice.

Development of human chronic pancreatitis is associated with intrapancreatic accumulation of pituitary adenylate cyclase-activating polypeptide (PACAP) accompanied with an altered inflammatory response (Michalski et al., Am J Physiol Gastrointest Liver Physiol. 2008;294:G50-G57). To investigate the role of pancreatic PACAP in the development of acute pancreatitis, we employed transgenic mice over-expressing PACAP in pancreatic beta-cells (PACAP-Tg). In comparison to wild-type mice, PACAP-Tg mice exhibited more severe pathophysiological signs of the cerulein-induced pancreatitis at 12 h, as evidenced by higher serum amylase and lipase levels accompanied by the exacerbation of pancreatic edema, necrosis, and inflammation. Cerulein treatment increased mRNA expression of several proinflammatory cytokines (TNFalpha, IL-1beta, and IL-6) at 12 h with similar magnitude both in wild-type and PACAP-Tg mice. In addition, the mRNA and protein levels of regenerating gene III beta (RegIIIbeta), a key factor in the pancreatic response to acute pancreatitis, were up-regulated at 24 h in wild-type mice upon cerulein administration, whereas they were attenuated in PACAP-Tg mice. These data indicate that over-expressed PACAP in pancreas enhances the cerulein-induced inflammatory response of both acinar cells, leading to aggravated acute pancreatitis, which was accompanied by a down-regulation of RegIIIbeta, an anti-inflammatory factor.

Markedly reduced white adipose tissue and increased insulin sensitivity in adcyap1-deficient mice.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide implicated in several metabolic functions, including insulin secretion and sympathoadrenal activation. To clarify the roles of PACAP in maintenance of whole-body glucose and lipid homeostasis, the impact of the deletion of PACAP on glucose homeostasis, body weight, and adipose tissue mass was examined by comparing mice lacking the Adcyap1 gene encoding PACAP (Adcyap1(-/-)) with wild-type littermate controls. Adcyap1(-/-) mice showed significant hypoinsulinemia, although being normoglycemic, and lower body weight as well as reduced food intake. They also showed greatly reduced white adipose tissue mass, in which the mRNA expression of adipocyte fatty acid-binding protein (aP2), a marker of adipocyte differentiation, was decreased. Glucose and insulin tolerance tests revealed increased insulin sensitivity in Adcyap1(-/-) mice. In accordance with these observations, plasma levels of resistin, an adipocytokine implicated in insulin resistance, were decreased in Adcyap1(-/-) mice. After a high-fat dietary challenge for six weeks, Adcyap1(-/-) mice still showed lower body weights and increased insulin sensitivity. These results indicate the crucial roles of PACAP in energy metabolism, including lipid metabolism, and in the regulation of body weight, raising the possibility that the PACAP-signaling pathway that favors energy storage could be a therapeutic target for obesity.