TUNEL-positive structures in activated microglia and SQSTM1/p62-positive structures in activated astrocytes in the neurodegenerative brain of a CLN10 mouse model

Neuronal ceroid lipofuscinosis is a group of pediatric neurodegenerative diseases. One of their causative genes, CLN10/CtsD, encodes cathepsin D, a major lysosomal protease. Central nervous system (CNS)-specific CtsD-deficient mice exhibit a neurodegenerative disease phenotype with accumulation of ceroid lipofuscins, granular osmiophilic deposits, and SQSTM1/p62. We focused on activated astrocytes and microglia in this neurodegenerative mouse brain, since there are few studies on the relationship between these accumulators and lysosomes in these glial cells. Activated microglia and astrocytes in this mouse thalamus at p24 were increased by approximately 2.5- and 4.6-fold compared with the control, while neurons were decreased by approximately half. Granular osmiophilic deposits were detected in microglial cell bodies and extended their processes in the thalamus. LAMP1-positive lysosomes, but not SQSTM1/p62 aggregates, accumulated in microglia of this mouse thalamus, whereas both lysosomes and SQSTM1/p62 aggregates accumulated in its astrocytes. TUNEL-positive signals were observed mainly in microglia, but few were observed in neurons and astrocytes. These signals were fragmented DNA from degenerated neurons engulfed by microglia or in the lysosomes of microglia. Abnormal autophagic vacuoles also accumulated in the lysosomes of microglia. Granular osmiophilic deposit-like structures localized to LAMP1-positive lysosomes in CtsD-deficient astrocytes. SQSTM1/p62-positive but LAMP1-negative membranous structures also accumulated in the astrocytes and were less condensed than typical granular osmiophilic deposits. These results suggest that CtsD deficiency leads to intracellular abnormalities in activated microglia and astrocytes in addition to neuronal degeneration.

Recent advances in in-resin correlative light and electron microscopy of Epon-embedded cells

Correlative fluorescent and electron microscopic images of the same section of epoxy (or other polymer)-embedded samples, hereafter referred to as 'in-resin CLEM', have been developed to improve the positional accuracy and Z-axis resolution limitations of conventional correlative light and electron microscopy (CLEM). High-pressure freezing and quick-freezing substitution result in in-resin CLEM of acrylic-based resin-embedded cells expressing green fluorescent protein, yellow fluorescent protein, mVenus and mCherry, which are sensitive to osmium tetroxide. The identification of osmium-resistant fluorescent proteins leads to the development of in-resin CLEM of Epon-embedded cells. Using subtraction-based fluorescence microscopy with a photoconvertible fluorescent protein, mEosEM-E, its green fluorescence can be observed in thin sections of Epon-embedded cells, and two-color in-resin CLEM using mEosEM-E and mScarlet-H can be performed. Green fluorescent proteins, CoGFP variant 0 and mWasabi, and far-red fluorescent proteins, mCherry2 and mKate2, are available for in-resin CLEM of Epon-embedded cells using the standard procedure for Epon-embedding with additional incubation. Proximity labeling is applied to in-resin CLEM to overcome the limitations of fluorescent proteins in epoxy resin. These approaches will contribute significantly to the future of CLEM analysis.

Application of immuno- and affinity labeling with fluorescent dyes to in-resin CLEM of Epon-embedded cells

In-resin CLEM (Correlative Light and Electron Microscopy) of Epon-embedded cells involves correlating fluorescence microscopy with electron microscopy in the same Epon-embedded ultrathin section. This method offers the advantage of high positional accuracy compared to standard CLEM. However, it requires the expression of recombinant proteins. In order to detect the localization of endogenous target(s) and their localized ultrastructures of Epon-embedded samples using in-resin CLEM, we investigated whether immunological and affinity-labeling using fluorescent dyes applied to in-resin CLEM of Epon-embedded cells. The orange fluorescent (λ_em ∼550 nm) and far-red (λ_em ∼650 nm) fluorescent dyes examined maintained a sufficient level of fluorescent intensity after staining with osmium tetroxide and subsequent dehydration treatment with ethanol. Immunological in-resin CLEM of mitochondria and the Golgi apparatus was achieved using anti-TOM20, anti-GM130 antibodies, and fluorescent dyes. Two-color in-resin CLEM revealed that wheat germ agglutinin-puncta showed the ultrastructures of multivesicular body-like structures. Finally, taking the advantage of high positional accuracy, volume in-resin CLEM of mitochondria in the semi-thin section (2 μm thick) of Epon-embedded cells was performed by focused ion beam scanning electron microscopy. These results suggested that the application of immunological reaction and affinity-labeling with fluorescent dyes to in-resin CLEM of Epon-embedded cells is suitable for analyzing the localization of endogenous targets and their ultrastructures by scanning and transmission electron microscopy.

Lack of Cathepsin D in the central nervous system results in microglia and astrocyte activation and the accumulation of proteinopathy-related proteins

Neuronal ceroid lipofuscinosis is one of many neurodegenerative storage diseases characterized by excessive accumulation of lipofuscins. CLN10 disease, an early infantile neuronal ceroid lipofuscinosis, is associated with a gene that encodes cathepsin D (CtsD), one of the major lysosomal proteases. Whole body CtsD-knockout mice show neurodegenerative phenotypes with the accumulation of lipofuscins in the brain and also show defects in other tissues including intestinal necrosis. To clarify the precise role of CtsD in the central nervous system (CNS), we generated a CNS-specific CtsD-knockout mouse (CtsD-CKO). CtsD-CKO mice were born normally but developed seizures and their growth stunted at around postnatal day 23 ± 1. CtsD-CKO did not exhibit apparent intestinal symptoms as those observed in whole body knockout. Histologically, autofluorescent materials were detected in several areas of the CtsD-CKO mouse's brain, including: thalamus, cerebral cortex, hippocampus, and cerebellum. Expression of ubiquitin and autophagy-associated proteins was also increased, suggesting that the autophagy-lysosome system was impaired. Microglia and astrocytes were activated in the CtsD-CKO thalamus, and inducible nitric oxide synthase (iNOS), an inflammation marker, was increased in the microglia. Interestingly, deposits of proteinopathy-related proteins, phosphorylated α-synuclein, and Tau protein were also increased in the thalamus of CtsD-CKO infant mice. Considering these results, we propose thatt the CtsD-CKO mouse is a useful mouse model to investigate the contribution of cathepsin D to the early phases of neurodegenerative diseases in relation to lipofuscins, proteinopathy-related proteins and activation of microglia and astrocytes.

OP0112 THE EVER-LARGEST ASIAN GWAS FOR SYSTEMIC SCLEROSIS AND TRANS-POPULATION META-ANALYSIS IDENTIFIED SEVEN NOVEL LOCI AND A CANDIDATE CAUSAL SNP IN A CIS-REGULATORY ELEMENT OF THE FCGR REGION

Background

Genome-wide association studies (GWASs) have identified 29 disease-associated single nucleotide polymorphisms (SNPs) for systemic sclerosis (SSc) in non-human leukocyte antigen (HLA) regions (1-7). While these GWASs have clarified genetic architectures of SSc, study subjects were mainly Caucasians limiting application of the findings to Asians.

Objectives

The study was conducted to identify novel causal variants for SSc specific to Japanese subjects as well as those shared with European population. We also aimed to clarify mechanistic effects of the variants on pathogenesis of SSc.

Methods

A total of 114,108 subjects comprising 1,499 cases and 112,609 controls were enrolled in the two-staged study leading to the ever-largest Asian GWAS for SSc. After applying a strict quality control both for genotype and samples, imputation was conducted using the reference panel of the phase 3v5 1,000 genome project data combined with a high-depth whole-genome sequence data of 3,256 Japanese subjects. We conducted logistic regression analyses and also combined the Japanese GWAS results with those of Europeans (6) by an inverse-variance fixed-effect model. Polygenicity and enrichment of functional annotations were evaluated by linkage disequilibrium score regression (LDSC), Haploreg and IMPACT programs. We also constructed polygenic risk score (PRS) to predict SSc development.

Results

We identified three (FCRLA-FCGR, TNFAIP3, PLD4) and four (EOMES, ESR1, SLC12A5, TPI1P2) novel loci in Japanese GWAS and a trans-population meta-analysis, respectively. One of Japanese novel risk SNPs, rs6697139, located within FCGR gene clusters had a strong effect size (OR 2.05, P=4.9×10-11). We also found the complete LD variant, rs10917688, was positioned in cis-regulatory element and binding motif for an immunomodulatory transcription factor IRF8 in B cells, another genome-wide significant locus in our trans-ethnic meta-analysis and the previous European GWAS. Notably, the association of risk allele of rs10917688 was significant only in the presence of the risk allele of the IRF8. Intriguingly, rs10917688 was annotated as one enhancer-related histone marks, H3K4me1, in B cells, implying that FCGR gene(s) in B cells may play an important role in the pathogenesis of SSc. Furhtermore, significant heritability enrichment of active histone marks and a transcription factor C-Myc were found in B cells both in European and Japanese populations by LDSC and IMPACT, highlighting a possibility of a shared disease mechanism where abnormal B-cell activation may be one of the key drivers for the disease development. Finally, PRS using effects sizes of European GWAS moderately fit in the development of Japanese SSc (AUC 0.593), paving a path to personalized medicine for SSc.

Conclusion

Our study identified seven novel susceptibility loci in SSc. Downstream analyses highlighted a novel disease mechanism of SSc where an interactive role of FCGR gene(s) and IRF8 may accelerate the disease development and B cells may play a key role on the pathogenesis of SSc.

References

[1]F. C. Arnett et al. Ann Rheum Dis, 2010.

[2]T. R. Radstake et al. Nat Genet, 2010.

[3]Y. Allanore et al. PLoS Genet, 2011.

[4]O. Gorlova et al. PLoS Genet, 2011.

[5]C. Terao et al. Ann Rheum Dis, 2017.

[6]E. López-Isac et al. Nat Commun, 2019.

[7]W. Pu et al. J Invest Dermatol, 2021.

Disclosure of Interests

None declared

A sublethal ATP11A mutation associated with neurological deterioration causes aberrant phosphatidylcholine flipping in plasma membranes

ATP11A translocates phosphatidylserine (PtdSer), but not phosphatidylcholine (PtdCho), from the outer to the inner leaflet of plasma membranes, thereby maintaining the asymmetric distribution of PtdSer. Here, we detected a de novo heterozygous point mutation of ATP11A in a patient with developmental delays and neurological deterioration. Mice carrying the corresponding mutation died perinatally of neurological disorders. This mutation caused an amino acid substitution (Q84E) in the first transmembrane segment of ATP11A, and mutant ATP11A flipped PtdCho. Molecular dynamics simulations revealed that the mutation allowed PtdCho binding at the substrate entry site. Aberrant PtdCho flipping markedly decreased the concentration of PtdCho in the outer leaflet of plasma membranes, whereas sphingomyelin (SM) concentrations in the outer leaflet increased. This change in the distribution of phospholipids altered cell characteristics, including cell growth, cholesterol homeostasis, and sensitivity to sphingomyelinase. Matrix-assisted laser desorption ionization-imaging mass spectrometry (MALDI-IMS) showed a marked increase of SM levels in the brains of Q84E-knockin mouse embryos. These results provide insights into the physiological importance of the substrate specificity of plasma membrane flippases for the proper distribution of PtdCho and SM.

No significant association between stable iodine intake and thyroid dysfunction in children after the Fukushima Nuclear Disaster: an observational study

PURPOSE

Stable iodine prophylaxis helps prevent childhood thyroid cancer in nuclear emergencies; however, there is limited information on its effect on thyroid function. This study aimed to examine thyroid function and autoimmunity among children and adolescents that took stable iodine after the Fukushima Nuclear Disaster.

METHODS

For this observational study, data were obtained from children and adolescents that underwent thyroid cancer screening at Hirata Central Hospital from April 2012 to March 2018. Participant characteristics, including possible hypothyroidism and hyperthyroidism, were compared between the prophylaxis and no-prophylaxis groups. Multivariable logistic regression models were used to assess for possible hypothyroidism, autoantibodies positive, and hyperthyroidism.

RESULTS

A total of 1,225 participants with stable iodine prophylaxis and 3,946 without prophylaxis were enrolled. Of those participants, blood samples were available for 144 and 1,201 participants in the prophylaxis and no-prophylaxis groups, respectively. There were 17 (11.8%) and 146 cases (12.2%) of possible hypothyroidism or autoantibodies positive cases in the prophylaxis and no-prophylaxis groups, respectively, and there were no cases and 3 cases (0.2%) of possible hyperthyroidism in those two groups, respectively. Multivariable analysis for possible hypothyroidism revealed no association between stable iodine intake and possible hypothyroidism or autoantibodies positive [odds ratio 0.716 (95% confidence interval 0.399-1.284)] (p = 0.262). We did not perform multivariable analysis for hyperthyroidism due to the limited number of cases.

CONCLUSION

Significant adverse effects of stable iodine intake on thyroid function were not observed among children and adolescents 7 years after the Fukushima Nuclear Disaster.

A new multi-tracer pellet injection for a simultaneous study of low- and mid/high-Z impurities in high-temperature plasmas

A new multi-tracer technique in the Tracer-Encapsulated Solid Pellet (TESPEL) method has been developed in order to acquire simultaneously the information about the behaviors of various impurities, i.e., to study concurrently the behaviors of low- and mid/high-Z impurities in magnetically confined high-temperature plasmas. In this new technique, an inorganic compound (for example, lithium titanate, Li₂TiO₃) is proposed to be used as a tracer embedded in the core of the TESPEL, instead of pure elements. The results of the proof-of-principle experiment clearly demonstrate the applicability of the new multi-tracer technique in the TESPEL method for the simultaneous study of behaviors of low- and mid/high-Z impurities in high-temperature plasmas.

Analysis of the Motional Stark Effect (MSE) diagnostic to measure the rotational transform and current profile in the Large Helical Device

The analysis method of the Motional Stark Effect (MSE) diagnostic to measure the rotational transform and current profiles in the Large Helical Device has been improved. This was done by using the Variational Moments Equilibrium Code to calculate an equilibrium database for various pressure profiles and current profiles. This method looks for the radial profile of the rotational transform in the equilibrium database that gives the best fit to the polarization angle profiles measured with the MSE diagnostic. This analysis improves the measurements of rotational transform, especially near the magnetic axis, where the sensitivity of the polarization angle measurements becomes low and the uncertainty due to error in the estimation of the Pfirsch-Schlüter current becomes large. The radial profiles of the rotational transform and current profiles for Electron Cyclotron Current Drive and Neutral Beam Current Drive are obtained in the new analysis method with a sufficiently high accuracy to discuss the discrepancy of the current density profiles between the measurements and the calculations.

Rectal cancer lateral lymph nodes: multicentre study of the impact of obturator and internal iliac nodes on oncological outcomes

BACKGROUND

In patients with rectal cancer, enlarged lateral lymph nodes (LLNs) result in increased lateral local recurrence (LLR) and lower cancer-specific survival (CSS) rates, which can be improved with (chemo)radiotherapy ((C)RT) and LLN dissection (LLND). This study investigated whether different LLN locations affect oncological outcomes.

METHODS

Patients with low cT3-4 rectal cancer without synchronous distant metastases were included in this multicentre retrospective cohort study. All MRI was re-evaluated, with special attention to LLN involvement and response.

RESULTS

More advanced cT and cN category were associated with the occurrence of enlarged obturator nodes. Multivariable analyses showed that a node in the internal iliac compartment with a short-axis (SA) size of at least 7 mm on baseline MRI and over 4 mm after (C)RT was predictive of LLR, compared with a post-(C)RT SA of 4 mm or less (hazard ratio (HR) 5.74, 95 per cent c.i. 2.98 to 11.05 vs HR 1.40, 0.19 to 10.20; P < 0.001). Obturator LLNs with a SA larger than 6 mm after (C)RT were associated with a higher 5-year distant metastasis rate and lowered CSS in patients who did not undergo LLND. The survival difference was not present after LLND. Multivariable analyses found that only cT category (HR 2.22, 1.07 to 4.64; P = 0.033) and margin involvement (HR 2.95, 1.18 to 7.37; P = 0.021) independently predicted the development of metastatic disease.

CONCLUSION

Internal iliac LLN enlargement is associated with an increased LLR rate, whereas obturator nodes are associated with more advanced disease with increased distant metastasis and reduced CSS rates. LLND improves local control in persistent internal iliac nodes, and might have a role in controlling systemic spread in persistent obturator nodes.Members of the Lateral Node Study Consortium are co-authors of this study and are listed under the heading Collaborators.

Cathepsin B and D deficiency in the mouse pancreas induces impaired autophagy and chronic pancreatitis

The major lysosomal proteases, Cathepsin B (CTSB), Cathepsin D (CTSD) and Cathepsin L (CTSL), are implicated in autophagic activity. To investigate the role of each cathepsin in the exocrine pancreas, we generated mice in which the pancreas was specifically deficient in Ctsb, Ctsd and Ctsl. Each of these gene knockout (KO) and Ctsb;Ctsl and Ctsd;Ctsl double-knockout (DKO) mice were almost normal. However, we found cytoplasmic degeneration in the pancreatic acinar cells of Ctsb;Ctsd DKO mice, similar to autophagy related 5 (Atg5) KO mice. LC3 and p62 (autophagy markers) showed remarkable accumulation and the numbers of autophagosomes and autolysosomes were increased in the pancreatic acinar cells of Ctsb;Ctsd DKO mice. Moreover, these Ctsb;Ctsd DKO mice also developed chronic pancreatitis (CP). Thus, we conclude that both Ctsb and Ctsd deficiency caused impaired autophagy in the pancreatic acinar cells, and induced CP in mice.

The sodium-glucose cotransporter 2 inhibitor tofogliflozin prevents diabetic kidney disease progression in type 2 diabetic mice

Trials on cardiovascular and renal outcomes in patients with type 2 diabetes have consistently demonstrated that sodium–glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of diabetic kidney disease (DKD) progression. However, their renal protective mechanisms have yet to be completely understood and the effect on albuminuria reduction in animal models is controversial. We investigated these issues using KK and KK‐A^y mice as a control (CTRL) and as a model for type 2 diabetes (DKD), respectively. KK‐A^y mice were treated with 0.015% tofogliflozin, which is an SGLT2 inhibitor, starting at seven weeks of age for eight weeks. Compared with the CTRL mice, the DKD mice had higher HbA1c levels and albuminuria. Although tofogliflozin treatment significantly lowered HbA1c levels, it did not reverse albuminuria. Tofogliflozin treatment enhanced damage in both the glomerular (i.e., enlarged mesangial area, increased foot process effacement rate, and decreased number of WT‐1‐positive cells) and tubulointerstitial (increased protein levels of KIM‐1 and MCP‐1, increased number of macrophages, and abnormal mitochondrial morphology) areas. Our results suggest that tofogliflozin may prevent glomerular and tubulointerstitial damage, partly by ameliorating hyperglycemia, renal inflammation, and abnormal mitochondrial morphology.

Characterization of starvation-induced autophagy in cerebellar Purkinje cells of pHluorin-mKate2-human LC3B transgenic mice

We generated a new transgenic mouse model that expresses a pHluorin-mKate2 fluorescent protein fused with human LC3B (PK-LC3 mice) for monitoring autophagy activity in neurons of the central nervous system. Histological analysis revealed fluorescent puncta in neurons of the cerebral cortex, hippocampus, cerebellar Purkinje cells, and anterior spinal regions. Using CLEM analysis, we confirmed that PK-LC3-positive puncta in the perikarya of Purkinje cells correspond to autophagic structures. To validate the usability of PK-LC3 mice, we quantified PK-LC3 puncta in Purkinje cells of mice kept in normal feeding conditions and of mice starved for 24 hours. Our results showed a significant increase in autophagosome number and in individual puncta areal size following starvation. To confirm these results, we used morphometry at the electron microscopic level to analyze the volume densities of autophagosomes and lysosomes/autolysosomes in Purkinje cells of PK-LC3 mice. The results revealed that the volume densities of autophagic structures increase significantly after starvation. Together, our data show that PK-LC3 mice are suitable for monitoring autophagy flux in Purkinje cells of the cerebellum, and potentially other areas in the central nervous system.

Autophagy Deficiency in Renal Proximal Tubular Cells Leads to an Increase in Cellular Injury and Apoptosis under Normal Fed Conditions

Renal proximal tubular epithelial cells are significantly damaged during acute kidney injury. Renal proximal tubular cell-specific autophagy-deficient mice show increased sensitivity against renal injury, while showing few pathological defects under normal fed conditions. Considering that autophagy protects the proximal tubular cells from acute renal injury, it is reasonable to assume that autophagy contributes to the maintenance of renal tubular cells under normal fed conditions. To clarify this possibility, we generated a knock out mouse model which lacks Atg7, a key autophagosome forming enzyme, in renal proximal tubular cells (Atg7^flox/flox;KAP-Cre⁺). Analysis of renal tissue from two months old Atg7^flox/flox;KAP-Cre⁺ mouse revealed an accumulation of LC3, binding protein p62/sequestosome 1 (a selective substrate for autophagy), and more interestingly, Kim-1, a biomarker for early kidney injury, in the renal proximal tubular cells under normal fed conditions. TUNEL (TdT-mediated dUTP Nick End Labeling)-positive cells were also detected in the autophagy-deficient renal tubular cells. Analysis of renal tissue from Atg7^flox/flox;KAP-Cre⁺ mice at different age points showed that tubular cells positive for p62 and Kim-1 continually increase in number in an age-dependent manner. Ultrastructural analysis of tubular cells from Atg7^flox/flox;KAP-Cre⁺ revealed the presence of intracellular inclusions and abnormal structures. These results indicated that autophagy-deficiency in the renal proximal epithelial tubular cells leads to an increase in injured cells in the kidney even under normal fed conditions.

Isotope Effect on Energy Confinement Time and Thermal Transport in Neutral-Beam-Heated Stellarator-Heliotron Plasmas

The isotope effect on energy confinement time and thermal transport has been investigated for plasmas confined by a stellarator-heliotron magnetic field. This is the first detailed assessment of an isotope effect in a stellarator heliotron. Hydrogen and deuterium plasmas heated by neutral beam injection on the Large Helical Device have exhibited no significant dependence on the isotope mass in thermal energy confinement time, which is not consistent with the simple gyro-Bohm model. A comparison of thermal diffusivity for dimensionally similar hydrogen and deuterium plasmas in terms of the gyroradius, collisionality, and thermal pressure has clearly shown robust confinement improvement in deuterium to compensate for the unfavorable mass dependence predicted by the gyro-Bohm model.

Lack of Cathepsin D in the Renal Proximal Tubular Cells Resulted in Increased Sensitivity against Renal Ischemia/Reperfusion Injury

Cathepsin D is one of the major lysosomal aspartic proteases that is essential for the normal functioning of the autophagy-lysosomal system. In the kidney, cathepsin D is enriched in renal proximal tubular epithelial cells, and its levels increase during acute kidney injury. To investigate how cathepsin D-deficiency impacts renal proximal tubular cells, we employed a conditional knockout CtsD^flox/−; Spink3^Cre mouse. Immunohistochemical analyses using anti-cathepsin D antibody revealed that cathepsin D was significantly decreased in tubular epithelial cells of the cortico-medullary region, mainly in renal proximal tubular cells of this mouse. Cathepsin D-deficient renal proximal tubular cells showed an increase of microtubule-associated protein light chain 3 (LC3; a marker for autophagosome/autolysosome)-signals and an accumulation of abnormal autophagic structures. Renal ischemia/reperfusion injury resulted in an increase of early kidney injury marker, Kidney injury molecule 1 (Kim-1), in the cathepsin D-deficient renal tubular epithelial cells of the CtsD^flox/−; Spink3^Cre mouse. Inflammation marker was also increased in the cortico-medullary region of the CtsD^flox/−; Spink3^Cre mouse. Our results indicated that lack of cathepsin D in the renal tubular epithelial cells led to an increase of sensitivity against ischemia/reperfusion injury.

A case with good response to belimumab for lupus nephritis complicated by IgG4-related disease

Immunoglobulin (Ig)G4-related disease (IgG4-RD) is an unusual complication of systemic lupus erythematosus (SLE). We report a case in which belimumab proved efficacious for not only SLE, but also IgG4-RD. A 58-year-old Japanese woman had suffered from photodermatosis and erythema on the limbs for 20 years. She presented in slight fever and fatigue since 2016. Laboratory data showed hypergammaglobulinemia, proteinuria and positive results for anti-nuclear antibody and anti-double-stranded DNA antibody. Furthermore, elevated levels of serum IgG4 were detected. Contrast-enhanced computed tomography disclosed multiple areas of poor enhancement in the kidneys. The patient was diagnosed with lupus nephritis and IgG4-RD from renal biopsy. Treatment was started with prednisolone at 40 mg/day and mycophenolate mofetil. Proteinuria and serological findings improved initially, but tapering the dose of glucocorticoid proved difficult. After treatment was started with belimumab, clinical symptoms and proteinuria resolved completely. The dose of glucocorticoid was successfully tapered and serum concentration of IgG4 fell further. This appears to represent the first report of a case in which both SLE and IgG4-RD were effectively treated using belimumab.

Atg9a deficiency causes axon-specific lesions including neuronal circuit dysgenesis

Conditional knockout mice for Atg9a, specifically in brain tissue, were generated to understand the roles of ATG9A in the neural tissue cells. The mice were born normally, but half of them died within one wk, and none lived beyond 4 wk of age. SQSTM1/p62 and NBR1, receptor proteins for selective autophagy, together with ubiquitin, accumulated in Atg9a-deficient neurosoma at postnatal d 15 (P15), indicating an inhibition of autophagy, whereas these proteins were significantly decreased at P28, as evidenced by immunohistochemistry, electron microscopy and western blot. Conversely, degenerative changes such as spongiosis of nerve fiber tracts proceeded in axons and their terminals that were occupied with aberrant membrane structures and amorphous materials at P28, although no clear-cut degenerative change was detected in neuronal cell bodies. Different from autophagy, diffusion tensor magnetic resonance imaging and histological observations revealed Atg9a-deficiency-induced dysgenesis of the corpus callosum and anterior commissure. As for the neurite extensions of primary cultured neurons, the neurite outgrowth after 3 d culturing was significantly impaired in primary neurons from atg9a-KO mouse brains, but not in those from atg7-KO and atg16l1-KO brains. Moreover, this tendency was also confirmed in Atg9a-knockdown neurons under an atg7-KO background, indicating the role of ATG9A in the regulation of neurite outgrowth that is independent of autophagy. These results suggest that Atg9a deficiency causes progressive degeneration in the axons and their terminals, but not in neuronal cell bodies, where the degradations of SQSTM1/p62 and NBR1 were insufficiently suppressed. Moreover, the deletion of Atg9a impaired nerve fiber tract formation.

A motional Stark effect diagnostic analysis routine for improved resolution of iota in the core of the large helical device

A new Motional Stark Effect (MSE) analysis routine has been developed for improved spatial resolution in the core of the Large Helical Device (LHD). The routine was developed to reduce the dependency of the analysis on the Pfirsch-Schlüter (PS) current in the core. The technique used the change in the polarization angle as a function of flux in order to find the value of diota/dflux at each measurement location. By integrating inwards from the edge, the iota profile can be recovered from this method. This reduces the results' dependency on the PS current because the effect of the PS current on the MSE measurement is almost constant as a function of flux in the core; therefore, the uncertainty in the PS current has a minimal effect on the calculation of the iota profile. In addition, the VMEC database was remapped from flux into r/a space by interpolating in mode space in order to improve the database core resolution. These changes resulted in a much smoother iota profile, conforming more to the physics expectations of standard discharge scenarios in the core of the LHD.

Small GTPase Rab1B is associated with ATG9A vesicles and regulates autophagosome formation

ATG9 is a membrane protein that is essential for autophagy and is considered to be directly involved in the early steps of autophagosome formation. Yeast Atg9 is mainly localized to small vesicles (Atg9 vesicles), whereas mammalian ATG9A is reportedly localized to the trans-Golgi network, the endosomal compartment, and other unidentified membrane structures. To dissect the ATG9A-containing membranes, we examined the subcellular localization of ATG9A and performed immunoisolation of those membranes. ATG9A-green fluorescent protein in human culture cells was observed as numerous puncta that move rapidly throughout the cytoplasm. We isolated these cytoplasmic membranes and found that they were small vesicles that resemble the yeast Atg9 vesicle. One of the proteins obtained via proteomic analyses of the mammalian ATG9A vesicle was Rab1, a small GTPase that is essential in endoplasmic reticulum-to-Golgi vesicle trafficking. Knockdown studies of Rab1B showed a suppression of autophagy. In these Rab1B-depleted cells, ATG9A accumulated in intermediate membrane structures at autophagosome formation sites. These results indicate that Rab1B is involved in regulating the proper development of autophagosomes.-Kakuta, S., Yamaguchi, J., Suzuki, C., Sasaki, M., Kazuno, S., Uchiyama, Y. Small GTPase Rab1B is associated with ATG9A vesicles and regulates autophagosome formation.

Small GTPase Rab1B is associated with ATG9A vesicles and regulates autophagosome formation

ATG9 is a membrane protein that is essential for autophagy and is considered to be directly involved in the early steps of autophagosome formation. Yeast Atg9 is mainly localized to small vesicles (Atg9 vesicles), whereas mammalian ATG9A is reportedly localized to the trans-Golgi network, the endosomal compartment, and other unidentified membrane structures. To dissect the ATG9A-containing membranes, we examined the subcellular localization of ATG9A and performed immunoisolation of those membranes. ATG9A-green fluorescent protein in human culture cells was observed as numerous puncta that move rapidly throughout the cytoplasm. We isolated these cytoplasmic membranes and found that they were small vesicles that resemble the yeast Atg9 vesicle. One of the proteins obtained via proteomic analyses of the mammalian ATG9A vesicle was Rab1, a small GTPase that is essential in endoplasmic reticulum-to-Golgi vesicle trafficking. Knockdown studies of Rab1B showed a suppression of autophagy. In these Rab1B-depleted cells, ATG9A accumulated in intermediate membrane structures at autophagosome formation sites. These results indicate that Rab1B is involved in regulating the proper development of autophagosomes.-Kakuta, S., Yamaguchi, J., Suzuki, C., Sasaki, M., Kazuno, S., Uchiyama, Y. Small GTPase Rab1B is associated with ATG9A vesicles and regulates autophagosome formation.

Measurements of metastatic renal cell tumours as determined by diffusion weighted imaging or computed tomography are in close agreement, a pilot study

BACKGROUND

Diffusion weighted magnetic resonance imaging (DWI) provides both functional and anatomical information regarding tumours but can also be used for tumour detection. Today, tumour treatment response in clinical trials is mainly assessed on Computed Tomography (CT) using established criteria. Despite availability of dedicated software, CT still requires significant manual work for selection and measurement in treatment response evaluation of solid tumours.

PURPOSE

To compare the maximum diameter of tumour lesions on CT with the corresponding measurements on diffusion weighted images.

MATERIALS AND METHODS

In this prospective cohort, metastatic lesions were identified on CT and on DWI in five patients with metastatic renal cell carcinoma before and after three months of treatment with pazopanib. Two radiologists independently measured the same lesions on axial CT images and separately also on axial DWI images. The measurements were compared between CT and DWI with respect to the number of target lesions measured, size of the lesions, size reduction due to treatment and the inter-observer variability. Wilcoxon signed rank test, linear regression and Bland-Altman plots were used for statistical analyses.

RESULTS

In this pilot study, there was no significant inter-observer variability in terms of numbers of lesion selected between CT and DWI. A significant reduction of lesion size was observed both for CT and DWI when post-treatment scans were compared to pre-treatment scans. There was no significant difference in measurement of lesion size on both pre- and post treatment scans between CT and DWI (p = 0.099 and p = 0.388 respectively).

CONCLUSION

Measurement of the size of metastatic lesions on the basis of axial DWI images are in close agreement with measurement based on conventional axial CT images, the most often employed approach in clinical trials today. The results in this pilot study can be used to estimate sufficient sample size in a larger trial with adequate power, were the results can be confirmed in a wider range of cancers other than renal cell carcinoma.

Novel method to rescue a lethal phenotype through integration of target gene onto the X-chromosome

The loss-of-function mutations of serine protease inhibitor, Kazal type 1 (SPINK1) gene are associated with human chronic pancreatitis, but the underlying mechanisms remain unknown. We previously reported that mice lacking Spink3, the murine homologue of human SPINK1, die perinatally due to massive pancreatic acinar cell death, precluding investigation of the effects of SPINK1 deficiency. To circumvent perinatal lethality, we have developed a novel method to integrate human SPINK1 gene on the X chromosome using Cre-loxP technology and thus generated transgenic mice termed “X-SPINK1“. Consistent with the fact that one of the two X chromosomes is randomly inactivated, X-SPINK1 mice exhibit mosaic pattern of SPINK1 expression. Crossing of X-SPINK1 mice with Spink3^+/− mice rescued perinatal lethality, but the resulting Spink3^−/−;XX^SPINK1 mice developed spontaneous pancreatitis characterized by chronic inflammation and fibrosis. The results show that mice lacking a gene essential for cell survival can be rescued by expressing this gene on the X chromosome. The Spink3^−/−;XX^SPINK1 mice, in which this method has been applied to partially restore SPINK1 function, present a novel genetic model of chronic pancreatitis.

Development of a new tracer-encapsulated solid pellet injection system for more precise control of tracer-impurity-deposit location in LHD

A new tracer-encapsulated solid pellet (TESPEL) injection system has been developed additionally for the LHD heliotron. This system has three-dimensionally bended guide tubes, which allows us to inject the TESPEL obliquely on a poloidal cross-section of the LHD plasma. Consequently, this system enables us to control a tracer-impurity-deposited location more precisely. Moreover, this system can make it possible for the tracer impurity to be deposited even only inside the ergodic region (outside a last closed flux surface of the LHD plasma). A stereoscopic fast camera system has been also developed for capturing a three-dimensional TESPEL trajectory.

Development of a cascade arc discharge source for an atmosphere-vacuum interface device

To realize a novel vacuum-atmosphere interface that does not require a large differential pumping system, a robust cascade arc discharge source called a plasma window is constructed and tested for long-term operation. By modifying a test plasma with a direct current discharge, a vacuum interface with a high gas pressure ratio of 1/407 between the discharge and expansion sections is demonstrated for currents as high as 20 A. No significant damage to the electrodes is observed during the operation. Analysis of the visible emission spectra reveals that a stationary, stable argon plasma having a temperature of 1 eV and a density of 1.5 × 10(16) cm(-3) is generated in the plasma channel.

Lactobacillus rhamnosus GG increases Toll-like receptor 3 gene expression in murine small intestine ex vivo and in vivo

Administration of Lactobacillus rhamnosus GG (LGG) has been reported to be therapeutically effective against acute secretory diarrhoea resulting from the structural and functional intestinal mucosal lesions induced by rotavirus infection; however, the underlying mechanisms remain to be completely elucidated. Because Toll-like receptor 3 (TLR3) plays a key role in the innate immune responses following the recognition of rotavirus, the present study examined whether LGG influences TLR3 gene expression in murine small intestine ex vivo and in vivo. We employed cultured intestinal organoids derived from small intestinal crypts as an ex vivo tissue model. LGG supplementation increased TLR3 mRNA levels in the intestinal organoids, as estimated by quantitative real-time polymerase chain reaction. Likewise, single and 7-day consecutive daily administrations of LGG increased TLR3 mRNA levels in the small intestine of C57BL/6N mice. The mRNA levels of other TLRs were not substantially altered both ex vivo and in vivo. In addition, LGG supplementation increased the mRNA levels of an antiviral type 1 interferon, interferon-α (IFN-α), and a neutrophil chemokine, CXCL1, upon stimulation with a synthetic TLR3 ligand, poly(I:C) in the intestinal organoids. LGG administration did not alter IFN-α and CXCL1 mRNA levels in the small intestine in vivo. Supplementation of other bacterial strains, Bifidobacterium bifidum and Lactobacillus paracasei, failed to increase TLR3 and poly(I:C)-stimulated CXCL1 mRNA levels ex vivo. We propose that upregulation of TLR3 gene expression may play a pivotal role in the therapeutic efficacy of LGG against rotavirus-associated diarrhoea. In addition, we demonstrated that intestinal organoids may be a promising ex vivo tissue model for investigating host-pathogen interactions and the antiviral action of probiotics in the intestinal epithelium.