High-cholesterol diet in combination with hydroxypropyl-beta-cyclodextrin induces NASH-like disorders in the liver of rats

Non-alcoholic fatty liver disease (NAFLD) is a general term for fatty liver disease not caused by viruses or alcohol. Fibrotic hepatitis, cirrhosis, and hepatocellular carcinoma can develop. The recent increase in NAFLD incidence worldwide has stimulated drug development efforts. However, there is still no approved treatment. This may be due in part to the fact that non-alcoholic steatohepatitis (NASH) pathogenesis is very complex, and its mechanisms are not well understood. Studies with animals are very important for understanding the pathogenesis. Due to the close association between the establishment of human NASH pathology and metabolic syndrome, several animal models have been reported, especially in the context of overnutrition. In this study, we investigated the induction of NASH-like pathology by enhancing cholesterol absorption through treatment with hydroxypropyl-beta-cyclodextrin (CDX). Female Sprague-Dawley rats were fed a normal diet with normal water (control group); a high-fat (60 kcal%), cholesterol (1.25 %), and cholic acid (0.5 %) diet with normal water (HFCC group); or HFCC diet with 2 % CDX water (HFCC+CDX group) for 16 weeks. Compared to the control group, the HFCC and HFCC+CDX groups showed increased blood levels of total cholesterol, aspartate aminotransferase, and alanine aminotransferase. At autopsy, parameters related to hepatic lipid synthesis, oxidative stress, inflammation, and fibrosis were elevated, suggesting the development of NAFLD/NASH. Elevated levels of endoplasmic reticulum stress-related genes were evident in the HFCC+CDX group. In the novel rat model, excessive cholesterol intake and accelerated absorption contributed to NAFLD/NASH pathogenesis.

Genetic architecture underlying IgG-RF production is distinct from that of IgM-RF

OBJECTIVE

HLA-DRB1 alleles, particularly the shared epitope (SE) alleles, are strongly associated with RA. Different genetic structures underlie the production of different autoantibodies in RA. While extensive genetic analyses were conducted for detailed profiles of ACPA, a representative autoantibody in RA, the genetic architecture underlying subfractions of RF other than IgM-RF, namely IgG-RF, known to be associated with rheumatoid vasculitis, is not well understood.

METHODS

We enrolled a total of 743 RA subjects whose detailed autoantibody (IgG-RF, IgM-RF, and ACPA) data were available. We evaluated co-presence and correlations of the levels of these autoantibodies. We analyzed associations between the presence or levels of the autoantibodies and HLA-DRB1 alleles for the 743 RA patients and 2,008 healthy controls.

RESULTS

We found both IgG-RF(+) and IgG-RF(-) RA subjects showed comparable associations with SE, which was not observed for the other autoantibodies. Furthermore, there was a clear difference in SE associations between IgG-RF(+) and (-) subsets; the association with the IgG-RF(+) subsets was solely driven by HLA-DRB1*04:05, the most frequent SE allele in the Japanese, while not only HLA-DRB1*04:05 but HLA-DRB1*04:01, less frequent in the Japanese but the most frequent SE in Europeans, were main drivers in IgG-RF(-) subset. We confirmed that these associations were irrespective of ACPA presence.

CONCLUSION

We found a unique genetic architecture of IgG-RF(-) RA, which showed a strong association with the SE allele less frequent among Japanese but the most frequent in Europeans. The findings could shed light on uncovered RA pathology.

A Novel CD135+ Subset of Mouse Monocytes with a Distinct Differentiation Pathway and Antigen-Presenting Properties

The mononuclear phagocyte system (MPS), composed of monocytes/macrophages and dendritic cells (DCs), plays a critical role at the interface of the innate and adaptive immune systems. However, the simplicity of MPS has been challenged recently by discoveries of novel cellular components. In the current study, we identified the CD135+ subset of monocytes as a novel class of APCs in mice. CD135+ monocytes were readily found in the bone marrow, spleen, and peripheral blood at steady state, and they expressed markers specific to DCs, including MHC class II and CD209a, along with markers for monocytes/macrophages. In addition, this subset phagocytosed bacteria and activated naive T lymphocytes, fulfilling the criteria for APCs. CD135+ monocytes were derived directly from macrophage DC progenitors, not from common monocyte progenitors or other monocytes, suggesting that these are distinct from conventional monocytes. These findings facilitate our understanding of the MPS network that regulates immune responses for host defense.

P-127 Identification of the optimal puncture position by image analysis may reduce oocyte degeneration in intracytoplasmic sperm injection (ICSI)

Study question

Is it possible to identify the optimal puncture position by image analysis where oocyte degeneration is reduced in ICSI procedure?

Summary answer

Visualizing the likelihood of unintentional membrane rupture (UMR) using image analysis can reduce oocyte degeneration and thereby generate more embryos available for treatment.

What is known already

It is known that the oocyte degeneration after both conventional-ICSI and Piezo-ICSI are often observed when UMR occurs during the puncturing process and the likelihood of UMR may depends on the location of the puncture site on the oolemma. Identifying the appropriate puncturing position may decrease the likelihood of membrane rupture and thus degeneration, however, there are no studies identifying the optimal puncture position during ICSI.

Study design, size, duration

We have developed the ICSI Position Detector (IPD), which can identify an area where rupture is likely to occur and visualize it on a video monitor. This study included 1,110 mature oocytes retrieved from 190 consenting patients. Matured oocytes were inseminated either by Conventional-ICSI (n = 437, average maternal age: 39.1±4.6 y.o.) or Piezo-ICSI (n = 673, average maternal age: 38.6±4.5 y.o.). ICSI was performed blindly, moving images were recorded and analyzed retrospectively during ICSI using IPD.

Participants/materials, setting, methods

Inseminated oocytes were subsequently divided into two groups according to IPD results, oocytes on which ICSI was performed at the position with a low chance of UMR (appropriate group), and with a high chance of UMR (non-appropriate group) by IPD. The rates of UMR, degeneration, fertilization (2PN), blastocyst formation, and good-quality blastocyst (Grade 3BB and above on day 5 by the Gardner scoring) were compared between the two groups of both conventional-ICSI and Piezo-ICSI.

Main results and the role of chance

The areas in which UMR is less likely to occur and more likely to occur are heterogeneously distributed. When ICSI was performed blindly, about half was from the non-appropriate position. In appropriate group of Piezo-ICSI, rates of UMR (4.3% vs. 17.4%, P < 0.001) and degeneration (1.0% vs. 5.7%, P < 0.001) were significantly lower than those of non-appropriate group, whereas rates of fertilization (88.0% vs. 78.4%, P < 0.01) and blastocyst formation (57.8% vs. 45.9%, P < 0.01) were significantly higher than those of non-appropriate group, respectively. The rate of good-quality blastocyst (28.8% vs. 24.9%) was in favor of appropriate group, but not significantly different. In appropriate group of Conventional-ICSI, rates of UMR (6.7% vs. 20.6%, P < 0.001) and degeneration (1.5% vs. 6.6%, P < 0.01) were significantly lower than those of non-appropriate group, whereas rate of fertilization (88.7% vs. 69.5, P < 0.001) was significantly higher than those of non-appropriate group, respectively. The rates of blastocyst formation (37.5% vs. 35.3%), good-quality blastocyst (21.3% vs. 18.7%) were all in favor of appropriate group, but not significantly different.

Limitations, reasons for caution

This is a single private fertility clinic study. Its reproducibility should be assessed in different laboratory conditions and the hands of different operators. Moreover, specific studies should be addressed on the effect of the other putative confounders under investigation (e.g. kind of ovulation trigger, patient demographics, culture environment, etc.).

Wider implications of the findings

This study demonstrated that the IPD is useful to identify the optimal puncture location site to prevent UMR on ICSI procedure, resulting in reducing UMR and degeneration of the oocytes and increasing culture results, thereby, generating more embryos available for transfer or cryopreservation.

Trial registration number

not applicable

Co-occurrence of relapsing polychondritis and autoimmune thyroid diseases

BACKGROUND

Relapsing polychondritis (RP) is a rare inflammatory disease characterized by recurrent inflammation and destruction of cartilaginous tissues. RP has characteristics of autoimmune disease and some reports have noted co-occurrence with autoimmune thyroid disease (AITD), consisting of Graves' disease (GD) and Hashimoto thyroiditis (HT). However, there have been no detailed studies on the co-occurrence of RP and AITD. In this study, we aimed to determine whether patients with RP tend to be complicated with AITD. We also analyzed the clinical and genetic profiles of patients in whom these diseases co-occur.

METHODS

We recruited 117 patients with RP and reviewed their medical records. Furthermore, we genotyped Human Leucocyte Antigen (HLA)-A, B Cw, DRB1, DQB1, and DPB1 alleles for 93 of the 117 patients. The prevalence of AITD among the patients with RP was compared with that among the general Japanese population. We also analyzed the clinical and genetic features of the patients with both RP and AITD.

RESULTS

The prevalence of GD among the patients with RP was 4.3% (5 among 117 patients), significantly higher than that among Japanese (0.11%) (p = 2.44 × 10-7, binomial test). RP patients with GD tended to have nasal involvement (p = 0.023) (odds ratio (OR) 2.58) and HLA-DPB1*02:02 (p = 0.035, OR 10.41). We did not find significant enrichment of HT in patients with RP.

CONCLUSIONS

Patients with RP appear to be at elevated risk of GD. Nasal involvement and HLA-DPB1*02:02 characterize the subset of RP patients with GD, which may guide attempts to characterize a distinct subtype of RP for precision medicine.

Pathophysiological Analysis of Uninephrectomized db/db Mice as a Model of Severe Diabetic Kidney Disease

Diabetic nephropathy, included in diabetic kidney disease (DKD), is the primary disease leading to end-stage renal disease (ESRD) or dialysis treatment, accounting for more than 40% of all patients with ESRD or receiving dialysis. Developing new therapeutics to prevent the transition to ESRD or dialysis treatment requires an understanding of the pathophysiology of DKD and an appropriate animal model for drug efficacy studies. In this study, we investigated the pathophysiology of diabetic kidney disease with type 2 diabetes in uninephrectomized db/db mice. In addition, the nephrectomized db/db mice from 10 weeks to 42 weeks were used to assess the efficacy of long-term administration of the angiotensin-II–receptor antagonist losartan. The blood and urinary biochemical parameters and the blood pressure which is a main pharmacological endpoint of the losartan therapy, were periodically measured. And at the end, histopathological analysis was performed. Uninephrectomized db/db mice clearly developed obesity and hyperglycemia from young age. Furthermore, they showed renal pathophysiological changes, such as increased urinary albumin-creatinine ratio (UACR) (the peak value 3104±986 in 40-week-old mice), glomerular hypertrophy and increased fibrotic areas in the tubulointerstitial tubules. The blood pressure in the losartan group was significantly low compared to the normotensive Vehicle group. However, as expected, Losartan suppressed the increase in UACR (829±500) indicating the medication was sufficient, but the histopathological abnormalities including tubular interstitial fibrosis did not improve. These results suggest that the uninephrectomized db/db mice are useful as an animal model of the severe DKD indicated by the comparison of the efficacy of losartan in this model with the efficacy of losartan in clinical practice.

Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Background

Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients.

Patients and methods

We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan–Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4.

Results

Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001).

Conclusions

First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.

•

Anti-PD-1 plus anti-CTLA-4 antibody therapy (PD1 + CTLA4) is an option for patients with advanced mucosal melanoma (MCM).

•

Data on the efficacy of PD1 + CTLA4 compared with PD-1 monotherapy (PD1) for MCM, however, are limited.

•

We retrospectively analyzed data from 329 Japanese patients with advanced MCM treated with PD1 or PD1 + CTLA4.

•

No significant differences in objective response rate, progression-free survival, or overall survival were observed.

•

Immune-related adverse events resulting in treatment cessation were higher in the PD1 + CTLA4 group.

Homodyne interferometry using a phase rotator for calibration of sine-cosine phase detection of a 70 GHz probe beam through a plasma

Homodyne interferometry using a motorized phase rotator for calibration of sine-cosine detection of the phase shift of a 70 GHz probe beam through a plasma has been developed. Four interferometers based on this interferometry have been installed on the low aspect ratio torus experiment (LATE) device with four horizontal probe beams on the mid-plane, which has measured the line-integrated electron densities with a time resolution of 10 μs and a resolution of line-integrated density of 5 × 10¹⁵ m^-2.

Impact of 2 Gy γ-irradiation on the hallmark characteristics of human bone marrow-derived MSCs

Two gray γ-irradiation is a widely employed basic module for total body irradiation (TBI) in allogeneic hematopoietic cell transplantation (HCT). The effects of γ-irradiation on hematopoietic and immune cells have been well investigated, but its effects on the bone marrow microenvironment (BMM) are unknown. Given the crucial contribution of mesenchymal/stromal stem cells (MSCs) in the BMM to hematopoiesis and osteogenesis, we investigated whether γ-irradiation affects the hallmark characteristics of human bone marrow-derived MSCs (BM-MSCs). Expansion of 2 Gy γ-irradiated BM-MSCs was delayed but eventually recovered. Colony formation and osteogenic, adipogenic, and chondrogenic differentiation capabilities of these cells were extensively suppressed. Irradiation of BM-MSCs did not affect the expansion of CD34 + hematopoietic stem and progenitor cells or production of CD11b + mature myeloid cells in co-cultures. However, it reduced production of CD19 + B-cells, as well as expression of CXCL12 and interleukin-7, which are essential for B-cell lymphopoiesis, in 2 Gy γ-irradiated BM-MSCs. Collectively, colony formation, osteogenic differentiation, and B-cell lymphopoiesis-supportive capabilities of γ-irradiated BM-MSCs were reduced. These effects may predispose survivors receiving HCT with TBI to defective bone formation and a perturbed humoral immune response.

Long-term follow-up of patients with anti-cyclic citrullinated peptide antibody-positive connective tissue disease: a retrospective observational study including information on the HLA-DRB1 allele and citrullination dependency

BACKGROUND

The anti-cyclic citrullinated peptide (CCP) antibody is a diagnostic biomarker of rheumatoid arthritis (RA). However, some non-RA connective tissue disease (CTD) patients also test positive for the anti-CCP antibody and, thus, may ultimately develop RA. We retrospectively investigated whether anti-CCP-positive non-RA CTD patients developed RA and attempted to identify factors that may differentiate RA-overlapping CTD from pure CTD.

METHODS

In total, 842 CTD patients with a primary diagnosis that was not RA were selected from our CTD database as of December 2012. Anti-CCP antibody titers were obtained from a retrospective chart review or measured using stored sera. RA was diagnosed according to the 1987 revised American College of Rheumatology classification criteria. Thirty-three anti-CCP-positive non-RA CTD patients were retrospectively followed up for the development of RA. Bone erosions on the hands and feet were assessed by X-ray. Citrullination dependency was evaluated by an in-house ELISA, the HLA-DRB1 allele was typed, and the results obtained were then compared between RA-overlapping and non-RA anti-CCP-positive CTD patients.

RESULTS

Two out of 33 anti-CCP-positive CTD patients (6.1%) developed RA during a mean follow-up period of 8.9 years. X-rays were examined in 27 out of the 33 patients, and only one (3.7%) showed bone erosions. The frequency of the HLA-DRB1 shared epitope (SE) and anti-CCP antibody titers were both significantly higher in anti-CCP-positive RA-overlapping CTD patients than in anti-CCP-positive non-RA CTD patients, while no significant differences were observed in citrullination dependency.

CONCLUSIONS

Anti-CCP-positive non-RA CTD patients rarely developed RA. HLA-DRB1 SE and anti-CCP antibody titers may facilitate the differentiation of RA-overlapping CTD from anti-CCP-positive non-RA CTD.

Correction to: Menatetrenone facilitates hematopoietic cell generation in a manner that is dependent on human bone marrow mesenchymal stromal/stem cells

In the original publication of the article, the Figs. 4 C, F and 5 B, C were published with unexpected appearance of dots.

Menatetrenone facilitates hematopoietic cell generation in a manner that is dependent on human bone marrow mesenchymal stromal/stem cells

Vitamin K2 in the form of menatetrenone has clinical benefits for osteoporosis and cytopenia. Given the dominant role of mesenchymal-osteolineage cells in the regulation of hematopoiesis, we investigated whether menatetrenone alters the hematopoiesis-supportive capability of human bone marrow mesenchymal stromal/stem cells (BM-MSCs). Menatetrenone up-regulated fibronectin protein expression in BM-MSCs without affecting their proliferation and differentiation capabilities. In addition, menatetrenone treatment of BM-MSCs enhanced generation of the CD34⁺ cell population in co-cultures through acceleration of the cell cycle. This effect was associated with cell-cell interactions mediated by VLA-4 and fibronectin. This proposal was supported by cytokine array and quantitative real-time PCR analyses, in which there were no significant differences between the expression levels of hematopoiesis-associated soluble factors in naïve and menatetrenone-treated BM-MSCs. Profiling of hematopoietic cells in co-cultures with menatetrenone-treated BM-MSCs demonstrated that they included significantly more CD34⁺CD38⁺ hematopoietic progenitor cells and cells skewed toward myeloid and megakaryocytic lineages than those in co-cultures with untreated BM-MSCs. Notably, myelodysplastic syndrome-derived cells were induced to undergo apoptosis when co-cultured with BM-MSCs, and this effect was enhanced by menatetrenone. Overall, our findings indicate that pharmacological treatment with menatetrenone bestows a unique hematopoiesis-supportive capability on BM-MSCs, which may contribute to the clinical improvement of cytopenia.

M2 Phenotype Macrophages Colocalize with Schwann Cells in Human Dental Pulp

Macrophages are immune cells with high plasticity that perform many functions related to tissue injury and repair. They are generally categorized as 2 functional phenotypes: M1 (proinflammatory) and M2 (anti-inflammatory and prohealing). To investigate the role of macrophages in human dental pulp, we examined the localization and distributional alterations of macrophages in healthy dental pulp as well as during the reparative process of pulp capping with mineral trioxide aggregate (MTA) and in cariously inflamed pulp of adult human teeth. We also quantified the populations of M1/M2 macrophages in healthy dental pulp by flow cytometric analysis. CD68⁺CD86⁺ cells (M1 phenotype) and CD68⁺CD163⁺ cells (M2 phenotype) were 2.11% ± 0.50% and 44.99% ± 2.22%, respectively, of 2.96% ± 0.41% CD68⁺ cells (pan-macrophages) in whole healthy dental pulp. Interestingly, M2 phenotype macrophages were associated with Schwann cells in healthy pulp, during mineralized bridge formation, and in pulp with carious infections in vivo. Furthermore, the M2 macrophages associated with Schwann cells expressed brain-derived neurotrophic factor (BDNF) under all in vivo conditions. Moreover, we found that plasma cells expressed BDNF. Coculture of Schwann cells isolated from human dental pulp and human monocytic cell line THP-1 showed that Schwann cells induced M2 phenotypic polarization of THP-1 cell-derived macrophages. The THP-1 macrophages that maintained contact with Schwann cells were stimulated, leading to elongation of their cell shape and expression of M2 phenotype marker CD163 in cocultures. In summary, we revealed the spatiotemporal localization of macrophages and potent induction of the M2 phenotype by Schwann cells in human dental pulp. M2 macrophages protect neural elements, whereas M1 cells promote neuronal destruction. Therefore, suppressing the neurodestructive M1 phenotype and maintaining the neuroprotective M2 phenotype of macrophages by Schwann cells may be critical for development of effective treatment strategies to maintain the viability of highly innervated dental pulp.

Toxicity of dextran stabilized fullerene C60 against C6 Glial cells

Elevated application potential of fullerene C₆₀ paved the way to think on its adverse effect when it reaches to biological system and environment. Though fullerenes are insoluble in water, various strategies are employed to make it soluble. Method of solubilization with organic solvents, yield cytotoxic responses both in vitro and in vivo. In this study, dextran was used to stabilize C₆₀ particle. Fourier transformed-infrared spectroscopy (FT-IR) and transition electron microscopy (TEM) were used for characterization and it confirms effective surface stabilization and morphological characteristics. This was followed by various cytotoxicity studies to evaluate its bio-nano interactions. The results of the study suggest that the dextran stabilized C₆₀ nanoparticles (Dex-C₆₀) forms uniform suspension in water and was stable up to 72 h. The C6 glial cell-Dex-C₆₀ interactions indicated that the Dex-C₆₀ nanoparticles penetrate deeper into the cells and cause dose dependent toxic response. The result of the study recommended that Dex-C₆₀ nanoparticles should undergo intensive risk assessment before biomedical applications and should take proper safety measure to avoid its entry to the environment.

White Matter Abnormalities in Multiple Sclerosis Evaluated by Quantitative Synthetic MRI, Diffusion Tensor Imaging, and Neurite Orientation Dispersion and Density Imaging

BACKGROUND AND PURPOSE

A number of MR-derived quantitative metrics have been suggested to assess the pathophysiology of MS, but the reports about combined analyses of these metrics are scarce. Our aim was to assess the spatial distribution of parameters for white matter myelin and axon integrity in patients with relapsing-remitting MS by multiparametric MR imaging.

MATERIALS AND METHODS

Twenty-four patients with relapsing-remitting MS and 24 age- and sex-matched controls were prospectively scanned by quantitative synthetic and 2-shell diffusion MR imaging. Synthetic MR imaging data were used to retrieve relaxometry parameters (R1 and R2 relaxation rates and proton density) and myelin volume fraction. Diffusion tensor metrics (fractional anisotropy and mean, axial, and radial diffusivity) and neurite orientation and dispersion index metrics (intracellular volume fraction, isotropic volume fraction, and orientation dispersion index) were retrieved from diffusion MR imaging data. These data were analyzed using Tract-Based Spatial Statistics.

RESULTS

Patients with MS showed significantly lower fractional anisotropy and myelin volume fraction and higher isotropic volume fraction in widespread white matter areas. Areas with different isotropic volume fractions were included within areas with lower fractional anisotropy. Myelin volume fraction showed no significant difference in some areas with significantly decreased fractional anisotropy in MS, including in the genu of the corpus callosum and bilateral anterior corona radiata, whereas myelin volume fraction was significantly decreased in some areas where fractional anisotropy showed no significant difference, including the bilateral posterior limb of the internal capsule, external capsule, sagittal striatum, fornix, and uncinate fasciculus.

CONCLUSIONS

We found differences in spatial distribution of abnormality in fractional anisotropy, isotropic volume fraction, and myelin volume fraction distribution in MS, which might be useful for characterizing white matter in patients with MS.

Effect of Gadolinium on the Estimation of Myelin and Brain Tissue Volumes Based on Quantitative Synthetic MRI

BACKGROUND AND PURPOSE

The effect of gadolinium on the estimation of myelin has not been reported. The aim of the current study was to investigate the effects of gadolinium on automatic myelin and brain tissue volumetry via quantitative synthetic MR imaging.

MATERIALS AND METHODS

The study included 36 patients who were referred for brain metastases screening, and quantitative synthetic MR imaging data before and after gadolinium-based contrast agent administration were analyzed retrospectively. Brain metastases were detected in 17 patients. WM volume, GM volume, CSF volume, non-WM/GM/CSF volume, myelin volume, brain parenchymal volume, myelin fraction (myelin volume/brain parenchymal volume), and intracranial volume were estimated. T1 and T2 relaxation times, proton density, and myelin partial volume per voxel averaged across the brain parenchyma were also analyzed.

RESULTS

In patients with and without metastases after gadolinium-based contrast agent administration, measurements of WM and myelin volumes, and myelin fraction were significantly increased (+26.65 and +29.42 mL, +10.14 and +12.46 mL, +0.88% and +1.09%, respectively), whereas measurements of GM, CSF, brain parenchymal, and intracranial volumes were significantly decreased (-36.23 and -34.49 mL, -20.77 and -18.94 mL, -6.76 and -2.84 mL, -27.41 and -21.84 mL, respectively). Non-WM/GM/CSF volume did not show a significant change. T1, T2, and proton density were significantly decreased (-51.34 and -46.84 ms, -2.67 and -4.70 ms, -1.05%, and -1.28%, respectively) after gadolinium-based contrast agent administration, whereas measurements of myelin partial volume were significantly increased (+0.78% and +0.75%, respectively).

CONCLUSIONS

Gadolinium had a significant effect on the automatic calculation of myelin and brain tissue volumes using quantitative synthetic MR imaging, which can be explained by decreases in T1, T2, and proton density.

Improving the Quality of Synthetic FLAIR Images with Deep Learning Using a Conditional Generative Adversarial Network for Pixel-by-Pixel Image Translation

BACKGROUND AND PURPOSE

Synthetic FLAIR images are of lower quality than conventional FLAIR images. Here, we aimed to improve the synthetic FLAIR image quality using deep learning with pixel-by-pixel translation through conditional generative adversarial network training.

MATERIALS AND METHODS

Forty patients with MS were prospectively included and scanned (3T) to acquire synthetic MR imaging and conventional FLAIR images. Synthetic FLAIR images were created with the SyMRI software. Acquired data were divided into 30 training and 10 test datasets. A conditional generative adversarial network was trained to generate improved FLAIR images from raw synthetic MR imaging data using conventional FLAIR images as targets. The peak signal-to-noise ratio, normalized root mean square error, and the Dice index of MS lesion maps were calculated for synthetic and deep learning FLAIR images against conventional FLAIR images, respectively. Lesion conspicuity and the existence of artifacts were visually assessed.

RESULTS

The peak signal-to-noise ratio and normalized root mean square error were significantly higher and lower, respectively, in generated-versus-synthetic FLAIR images in aggregate intracranial tissues and all tissue segments (all P < .001). The Dice index of lesion maps and visual lesion conspicuity were comparable between generated and synthetic FLAIR images (P = 1 and .59, respectively). Generated FLAIR images showed fewer granular artifacts (P = .003) and swelling artifacts (in all cases) than synthetic FLAIR images.

CONCLUSIONS

Using deep learning, we improved the synthetic FLAIR image quality by generating FLAIR images that have contrast closer to that of conventional FLAIR images and fewer granular and swelling artifacts, while preserving the lesion contrast.

Correction: Myeloproliferative leukemia protein activation directly induces fibrocyte differentiation to cause myelofibrosis

Owing to the insufficient specificity of the anti-myeloproliferative leukemia protein (MPL) antibody in the original version of this Article, Figure 6 and parts of Figures 2a, 4e, and 5a do not represent the correct information. The corrected version of Figure 6 is in this correction and those of Figures 2a, 4e, and 5a are shown in the supplemental information.

Studies on Production of Antithrombin III with Special Reference to Endotoxin-Induced DIC in Dogs

The production of antithrombin III (AT III) was studied using Se-75-selenomethionine as a tracer in dogs with disseminated intravascular coagulation (DIC) experimentally induced by endotoxin infusion. Using canine AT III purified by heparin-Sepharose affinity chromatography, antiserum against canine AT III was raised in rabbit. To study the production of plasma AT III, Se-75-selenomethionine was injected into the dog and thereafter the radioactivity incorporated into plasma AT III immunoprecipitated by anti-AT III rabbit serum was serially measured. In normal control dogs, peak radioactivity incorporated into AT III fraction was 970 ± 55 (mean ± SE) cpm/mg of AT III. It was 1196 ± 51.5 cpm/mg, 2748 ± 826 cpm/mg and 1057 ± 74 cpm/mg when Se-75-selenomethionine was injected 6 h, 24 h and 48 h after a single infusion with one mg of endotoxin/kg body weight of dogs, and was 1.2 times, 2.8 times and 1.1 times more than normal control dogs, respectively. Plasma AT III levels decreased to a minimum of 26.7 ± 4.9 mg/dl within 6 h after endotoxin infusion and returned to normal levels by 2 to 3 days after the infusion. Since the catabolic rate of AT III was evidently accelerated, judging from the more rapid decay of the AT III radioactivity, it is suggested that the production of AT III is markedly increased in dogs with DIC induced by endotoxin infusion even during a period of low plasma level.

Diabetic macular edema-like ocular lesions in male spontaneously diabetic torii fatty rats

Diabetic macular edema (DME) is a major factor contributing to visual disabilities in diabetic patients, and the number of patients is increasing. Animal models play a key role in the development of novel therapies. In this study, pathophysiological analyses of ocular lesions in Spontaneously Diabetic Torii (SDT) fatty rats were performed. First, vascular endothelial growth factor (VEGF) concentrations in vitreous humor, retinal vascular permeability and retinal thickness were measured in SDT fatty rats (Experiment 1). Furthermore, the pharmacological effects of two anti-diabetic drugs, phlorizin and pioglitazone, on retinal lesions were evaluated (Experiment 2). As results, the SDT fatty rats exhibited VEGF increase in vitreous humor at 8 and 16 weeks of age, and both retinal vascular hyperpermeability and retinal thickening at 16 weeks of age. In particular, the layers between the retinal internal limiting membrane and the outer nuclear layer were thickened. Phlorizin treatment from 4 to 16 weeks of age improved hyperglycemia and normalized retinal thickness; however, the effect of pioglitazone on retinal thickness was not strong despite the normalization of hyperglycemia. These data demonstrate that the male SDT fatty rat is a useful model for developing new therapeutic approaches in DME.

HLA-DRB1 Analysis Identified a Genetically Unique Subset within Rheumatoid Arthritis and Distinct Genetic Background of Rheumatoid Factor Levels from Anticyclic Citrullinated Peptide Antibodies

OBJECTIVE

HLA-DRB1 is the most important locus associated with rheumatoid arthritis (RA) and anticitrullinated protein antibodies (ACPA). However, fluctuations of rheumatoid factor (RF) over the disease course have made it difficult to define fine subgroups according to consistent RF positivity for the analyses of genetic background and the levels of RF.

METHODS

A total of 2873 patients with RA and 2008 healthy controls were recruited. We genotyped HLA-DRB1 alleles for the participants and collected consecutive data of RF in the case subjects. In addition to RF+ and RF- subsets, we classified the RF+ subjects into group 1 (constant RF+) and group 2 (seroconversion). We compared HLA-DRB1 alleles between the RA subsets and controls and performed linear regression analysis to identify HLA-DRB1 alleles associated with maximal RF levels. Omnibus tests were conducted to assess important amino acid positions.

RESULTS

RF positivity was 88%, and 1372 and 970 RF+ subjects were classified into groups 1 and 2, respectively. RF+ and RF- showed similar genetic associations to ACPA+ and ACPA- RA, respectively. We found that shared epitope (SE) was more enriched in group 2 than 1, p = 2.0 × 10^-5, and that amino acid position 11 showed a significant association between 1 and 2, p = 2.7 × 10^-5. These associations were independent of ACPA positivity. SE showed a tendency to be negatively correlated with RF titer (p = 0.012). HLA-DRB1*09:01, which reduces ACPA titer, was not associated with RF levels (p = 0.70).

CONCLUSION

The seroconversion group was shown to have distinct genetic characteristics. The genetic architecture of RF levels is different from that of ACPA.

Graft-Versus-Host Disease Amelioration by Human Bone Marrow Mesenchymal Stromal/Stem Cell-Derived Extracellular Vesicles Is Associated with Peripheral Preservation of Naive T Cell Populations

A substantial proportion of patients with acute graft-versus-host disease (aGVHD) respond to cell therapy with culture-expanded human bone marrow mesenchymal stromal/stem cells (BM-MSCs). However, the mechanisms by which these cells can ameliorate aGVHD-associated complications remain to be clarified. We show here that BM-MSC-derived extracellular vesicles (EVs) recapitulated the therapeutic effects of BM-MSCs against aGVHD. Systemic infusion of human BM-MSC-derived EVs prolonged the survival of mice with aGVHD and reduced the pathologic damage in multiple GVHD-targeted organs. In EV-treated GVHD mice, CD4+ and CD8+ T cells were suppressed. Importantly, the ratio of CD62L-CD44+ to CD62L + CD44- T cells was decreased, suggesting that BM-MSC-derived EVs suppressed the functional differentiation of T cells from a naive to an effector phenotype. BM-MSC-derived EVs also preserved CD4 + CD25 + Foxp3+ regulatory T cell populations. In a culture of CD3/CD28-stimulated human peripheral blood mononuclear cells with BM-MSC-derived EVs, CD3+ T cell activation was suppressed. However, these cells were not suppressed in cultures with EVs derived from normal human dermal fibroblasts (NHDFs). NHDF-derived EVs did not ameliorate the clinical or pathological characteristics of aGVHD in mice, suggesting an immunoregulatory function unique to BM-MSC-derived EVs. Microarray analysis of microRNAs in BM-MSC-derived EVs versus NHDF-derived EVs showed upregulation of miR-125a-3p and downregulation of cell proliferative processes, as identified by Gene Ontology enrichment analysis. Collectively, our findings provide the first evidence that amelioration of aGVHD by therapeutic infusion of BM-MSC-derived EVs is associated with the preservation of circulating naive T cells, possibly due to the unique microRNA profiles of BM-MSC-derived EVs. Stem Cells 2018;36:434-445.

MR Imaging Features of the Cerebellum in Adult-Onset Neuronal Intranuclear Inclusion Disease: 8 Cases

Neuronal intranuclear inclusion disease is a neurodegenerative disorder pathologically characterized by eosinophilic hyaline intranuclear inclusions. A high-intensity signal along the corticomedullary junction on DWI has been described as a specific MR imaging finding of the cerebrum in neuronal intranuclear inclusion disease. However, MR imaging findings of the cerebellum in neuronal intranuclear inclusion disease have not been fully evaluated. Here, we review MR imaging findings of the cerebellum in a series of 8 patients with pathologically confirmed neuronal intranuclear inclusion disease. The MR imaging results showed cerebellar atrophy (8/8 patients) and high-intensity signal on FLAIR images in the medial part of the cerebellar hemisphere right beside the vermis (the "paravermal area") (6/8) and in the middle cerebellar peduncle (4/8). The paravermal abnormal signals had a characteristic distribution, and they could be an indicator of the diagnosis of neuronal intranuclear inclusion disease even when using the results of past MR imaging examinations in which DWI findings were not examined.

Effects of acute exposure to low-dose radiation on the characteristics of human bone marrow mesenchymal stromal/stem cells

Background

In recent years, increasing attention has been paid to the effects of low-dose irradiation on human health. We examined whether low-dose irradiation affected the functions of mesenchymal stromal/stem cells (MSCs), which are tissue/organ-supportive stem cells, derived from bone marrow (BM).

Methods

Normal human BM-MSCs from five healthy individuals were used in this study. Culture-expanded BM-MSCs were exposed to 0.1 gray (Gy) of γ-radiation (Cesium-137) at a rate of 0.8 Gy/min (Ir-MSCs), and their expansion, multi-differentiation, and hematopoiesis-supportive capabilities were investigated.

Results

The expansion of BM-MSCs was transiently delayed after low-dose γ-irradiation compared with that of non-irradiated BM-MSCs (non-Ir-MSCs) in two out of five lots. Adipogenic and osteogenic differentiation capabilities were not significantly affected by low-dose irradiation, although one lot of BM-MSCs tended to have transiently reduced differentiation. When human BM hematopoietic stem/progenitor cells (HPCs) were co-cultured with Ir-MSCs, the generation of CD34⁺CD38⁺ cells from HPCs was enhanced compared with that in co-cultures with non-Ir-MSCs in two out of five lots. The mRNA expression level of interleukin (IL)-6 was increased and those of stem cell factor (SCF) and fms-related tyrosine kinase 3 ligand (Flt3L) were decreased in the affected lots of Ir-MSCs. In the other three lots of BM-MSCs, a cell growth delay, enhanced generation of CD34⁺CD38⁺ cells from HPCs in co-culture, and a combination of increased expression of IL-6 and decreased expression of SCF and Flt3L were not observed. Of note, the characteristics of these affected Ir-MSCs recovered to a similar level as those of non-Ir-MSCs following culture for 3 weeks.

Conclusions

Our results suggest that acute exposure to low-dose (0.1 Gy) radiation can transiently affect the functional characteristics of human BM-MSCs.

Isolation of mesenchymal stromal/stem cells from cryopreserved umbilical cord blood cells

Umbilical cord blood (UCB) has advantages over other tissues because it can be obtained without an invasive procedure and complex processing. We explored the availability of cryopreserved UCB cells as a source of mesenchymal stromal/stem cells (MSCs). MSCs were successfully isolated from six of 30 UCB units (median volume, 34.0 mL; median nucleated cell number, 4.4×10⁸) that were processed and cryopreserved using CP-1/human serum albumin. This isolation rate was lower than that (57%) from non-cryopreserved UCB cells. The number of nucleated cells before and after hydroxyethyl starch separation, UCB unit volume, and cell viability after thawing did not significantly differ between UCB units from which MSCs were successfully isolated and those from which they were not. When CryoSure-DEX40 was used as a cryoprotectant, MSCs were isolated from two of ten UCB units. Logistic regression analysis demonstrated that the cryopreservation method was not significantly associated with the success of MSC isolation. The isolated MSCs had a similar morphology and surface marker expression profile as bone marrow-derived MSCs and were able to differentiate into osteogenic, adipogenic, and chondrogenic cells. In summary, MSCs can be isolated from cryopreserved UCB cells. However, the cryopreservation process reduces the isolation rate; therefore, freshly donated UCB cells are preferable for the isolation of MSCs.

Constitutively active ABL family kinases, TEL/ABL and TEL/ARG, harbor distinct leukemogenic activities in vivo

ABL (ABL1) and ARG (ABL2) are highly homologous to each other in overall domain structure and amino-acid sequence, with the exception of their C termini. As with ABL, translocations that fuse ARG to ETV6/TEL have been identified in patients with leukemia. To assess the in vivo leukemogenic activity of constitutively active ABL and ARG, we generated a bone marrow (BM) transplantation model using the chimeric forms TEL/ABL and TEL/ARG, which have comparable kinase activities. TEL/ABL rapidly induced fatal myeloid leukemia in recipient mice, whereas recipients of TEL/ARG-transduced cells did not develop myeloid leukemia, instead, they succumbed to a long-latency infiltrative mastocytosis that could be adoptively transferred to secondary recipients. Swapping of the C termini of ABL and ARG altered disease latency and phenotypes. In a detailed in vitro study, TEL/ARG strongly promoted mast cell differentiation in response to stem cell factor or interleukin-3, whereas TEL/ABL preferentially induced myeloid differentiation of hematopoietic stem/progenitor cells. These results indicate that ABL and ARG kinase activate distinct differentiation pathways to induce specific diseases in vivo, that is, myeloid leukemia and mastocytosis, respectively. Further elucidation of the differences in their properties should provide important insight into the pathogenic mechanisms of oncogenes of the ABL kinase family.

Pharmacological targeting of bone marrow mesenchymal stromal/stem cells for the treatment of hematological disorders

The therapeutic effects of mesenchymal stromal/stem cells (MSCs) are mainly based on three characteristics: immunomodulation, tissue regeneration, and hematopoietic support. Cell therapy using culture-expanded MSCs is effective in some intractable bone and hemato-immune disorders; however, its efficacy is limited. In this article, we review the previous efforts to improve the clinical outcomes of cell therapy using MSCs for such disorders. We describe pharmacological targeting of endogenous bone marrow-derived MSCs as a crucial quality-based intervention to establish more effective MSC-based therapies.

Differential Expression and Roles of Secreted Frizzled-Related Protein 5 and the Wingless Homolog Wnt5a in Periodontitis

The Wingless/integrase-1 (Wnt) family of protein ligands and their functional antagonists, secreted frizzled-related proteins (sFRPs), regulate various biological processes ranging from embryonic development to immunity and inflammation. Wnt5a and sFRP5 comprise a typical ligand/antagonist pair, and the former molecule was recently detected at the messenger RNA (mRNA) level in human periodontitis. The main objective of this study was to investigate the interrelationship of expression of Wnt5a and sFRP5 in human periodontitis (as compared to health) and to determine their roles in inflammation and bone loss in an animal model. We detected both Wnt5a and sFRP5 mRNA in human gingiva, with Wnt5a dominating in diseased and sFRP5 in healthy tissue. Wnt5a and sFRP5 protein colocalized in the gingival epithelium, suggesting epithelial cell expression, which was confirmed in cultured human gingival epithelial cells (HGECs). The HGEC expression of Wnt5a and sFRP5 was differentially regulated by a proinflammatory stimulus (lipopolysaccharide [LPS] from Porphyromonas gingivalis) in a manner consistent with the clinical observations (i.e., LPS upregulated Wnt5a and downregulated sFRP5). In HGECs, exogenously added Wnt5a enhanced whereas sFRP5 inhibited LPS-induced inflammation, as monitored by interleukin 8 production. Consistent with this, local treatment with sFRP5 in mice subjected to ligature-induced periodontitis inhibited inflammation and bone loss, correlating with decreased numbers of osteoclasts in bone tissue sections. As in humans, mouse periodontitis was associated with high expression of Wnt5a and low expression of sFRP5, although this profile was reversed after treatment with sFRP5. In conclusion, we demonstrated a novel reciprocal relationship between sFRP5 and Wnt5a expression in periodontal health and disease, paving the way to clinical investigation of the possibility of using the Wnt5a/sFRP5 ratio as a periodontitis biomarker. Moreover, we showed that sFRP5 blocks experimental periodontal inflammation and bone loss, suggesting a promising platform for the development of a new host modulation therapy in periodontitis.

A Rare Case of Adult Autoimmune Neutropenia Successfully Treated with Prednisolone

Autoimmune neutropenia (AIN) is a rare disorder that may cause life-threatening infections. In adults, most cases are secondary to other pathological conditions, and primary AIN is extremely rare. We herein report a case involving a 57-year-old woman diagnosed with AIN. A granulocyte immunofluorescence test detected autoantibodies against human neutrophil antigens in her serum, while various examinations revealed no other causes of neutropenia, suggesting her AIN was primary. She was refractory to granulocyte-colony-stimulating factor but responded to prednisolone. Her neutrophil count remained normal after gradual discontinuation of prednisolone. Diagnostic procedures and optimal treatments for this disorder need to be established.

Ethics for clinical research

In order to translate research results obtained with technical innovations into the novel therapeutic approaches expeditiously, it is mandatory that both researchers and clinicians collaborate with pharmaceutical companies. In other words, investigators, pharmaceutical companies, and patients should work together to make newly innovative drugs more patient-friendly and more effective, with fewer adverse side effects. Patient cooperation is also indispensable for carrying out investigator-initiated clinical trials providing informative evidence for the development of clinical practice guidelines. In order to achieve these goals, it is necessary that the general public allow the implementation of investigatorinitiated clinical trials. For this purpose, it is mandatory to ripen the "social soil", while at the same time building a "system" including such essentials as regulations. Enhancing the transparency of conflicts of interest is one aspect of such a "system", and it is impossible to ripen the "social soil" in the settings of scientific misconduct and fraudulent medical research or clinical trials. In order to foster the "social soil" concept, it is clearly important to cultivate firm insights and lofty ethics of individual physicians and researchers.

Combination of panobinostat with ponatinib synergistically overcomes imatinib-resistant CML cells

The major mechanism of imatinib (IM) resistance of CML is the reactivation of ABL kinase either through BCR-ABL gene amplification or mutation. We investigated the cytotoxicity of a pan-ABL tyrosine kinase inhibitor, ponatinib, and a pan-histone deacetylase inhibitor, panobinostat, against IM-resistant CML cells in vitro. Two different IM-resistant cell lines, K562/IM-R1 and Ba/F3/T315I were evaluated in comparison with their respective, parental cell lines, K562 and Ba/F3. K562/IM-R1 overexpressed BCR-ABL due to gene amplification. Ba/F3/T315I was transfected with a BCR-ABL gene encoding T315I-mutated BCR-ABL. Ponatinib inhibited the growth of both K562/IM-R1 and Ba/F3/T315I as potently as it inhibited their parental cells with an IC50 of 2-30 nM. Panobinostat also similarly inhibited the growth of all of the cell lines with an IC50 of 40-51 nM. This was accompanied by reduced histone deacetylase activity, induced histone H3 acetylation, and an increased protein level of heat shock protein 70, which suggested disruption of heat shock protein 90 chaperone function for BCR-ABL and its degradation. Importantly, the combination of ponatinib with panobinostat showed synergistic growth inhibition and induced a higher level of apoptosis than the sum of the apoptosis induced by each agent alone in all of the cell lines. Ponatinib inhibited phosphorylation not only of BCR-ABL but also of downstream signal transducer and activator of transcription 5, protein kinase B, and ERK1/2 in both K562/IM-R1 and Ba/F3/T315I, and the addition of panobinostat to ponatinib further inhibited these phosphorylations. In conclusion, panobinostat enhanced the cytotoxicity of ponatinib towards IM-resistant CML cells including those with T315I-mutated BCR-ABL.

Targeting self-renewal pathways in cancer stem cells: clinical implications for cancer therapy

Extensive cancer research in the past few decades has identified the existence of a rare subpopulation of stem cells in the grove of cancer cells. These cells are known as the cancer stem cells marked by the presence of surface biomarkers, multi-drug resistance pumps and deregulated self-renewal pathways (SRPs). They have a crucial role in provoking cancer cells leading to tumorigenesis and its progressive metastasis. Cancer stem cells (CSCs) are much alike to normal stem cells in their self-renewal mechanisms. However, deregulations in the SRPs are seen in CSCs, making them resistant to conventional chemotherapeutic agents resulting in the tumor recurrence. Current treatment strategies in cancer fail to detect and differentiate the CSCs from their non-tumorigenic progenies owing to absence of specific biomarkers. Now, it has become imperative to understand complex functional biology of CSCs, especially the signaling pathways to design improved treatment strategies to target them. It is hopeful that the SRPs in CSCs offer a promising target to alter their survival strategies and impede their tumorigenic potential. However, there are many perils associated with the direct targeting method by conventional therapeutic agents such as off targets, poor bioavailability and poor cellular distribution. Recent evidences have shown an increased use of small molecule antagonists directly to target these SRPs may lead to severe side-effects. An alternative to solve these issues could be an appropriate nanoformulation. Nanoformulations of these molecules could provide an added advantage for the selective targeting of the pathways especially Hedgehog, Wnt, Notch and B-cell-specific moloney murine leukemia virus integration site 1 in the CSCs while sparing the normal stem cells. Hence, to achieve this goal a complete understanding of the molecular pathways corroborate with the use of holistic nanosystem (nanomaterial inhibition molecule) could possibly be an encouraging direction for future cancer therapy.

[Research ethics and conflicts of interest]

Translating research results to clinical settings requires that both researchers and clinicians work together with pharmaceutical companies. At the same time, however, it must be recognized that pharmaceutical companies are basically profit-motivated organizations. When pharmaceutical companies develop deeper doctor-patient relationships, the benefits of individual doctors and organizations inevitably conflict with the benefits or interests of patients. To promote industry-university cooperative activities, research quality and research ethics should be of major importance and we must ensure the reliability of the scientific nature and ethics of the research for the sake of the public. In other words, "confirming the quality and reliability of research", "ensuring transparency", and "accountability of research activity" are all clearly warranted. For this purpose, it is mandatory that each individual involved has the ethical sophistication and professionalism expected of doctors and researchers. Each physician and researcher must bear in mind that firm insights and the highest ethical judgments regarding the problems of conflict of interest, by themselves, are the only and the final barrier preserving the fairness and transparency of medical research.

An association between amino acid position 74 of HLA-DRB1 and anti-citrullinated protein antibody levels in Japanese patients with anti-citrullinated protein antibody-positive rheumatoid arthritis

OBJECTIVE

Anti-citrullinated protein antibodies (ACPAs) are highly specific to rheumatoid arthritis (RA), and strong associations between HLA-DRB1 alleles and ACPA levels have been detected in RA patients. We undertook this study to elucidate the associations between particular amino acid positions in HLA-DRB1 and ACPA levels in patients with RA.

METHODS

We analyzed ACPA data on a total of 4,371 Japanese ACPA-positive RA patients in whom HLA-DRB1 allele genotyping had been performed. Generalized linear regression analysis and omnibus testing were carried out to determine associations of HLA-DRB1 alleles, amino acid residues, or amino acid positions with levels of ACPA.

RESULTS

HLA-DRB1*09:01 and HLA-DR15 were confirmed to be associated with ACPA levels. HLA-DRB1*08:03 and DRB1*14:06 were associated with reduced and increased ACPA levels, respectively. We detected a strong association between ACPA levels and amino acid position 74 (P = 1.9 × 10(-51) ). The association was mainly conferred by alanine residue (P = 4.5 × 10(-51) ). After adjustment for position 74, amino acid positions 60 and 57 were found to be associated with ACPA levels. Amino acid positions 74 and 57 had previously been reported to be associated with susceptibility to ACPA-positive RA in Asians. Combinations of the amino acid residues at position 74 and position 60 or 57 could induce improvement in Akaike's information criterion comparable to that induced by the 5 significant HLA-DRB1 alleles (HLA-DRB1*08:03, DRB1*09:01, DRB1*14:06, DRB1*15:01, and DRB1*15:02).

CONCLUSION

Amino acid position 74 in HLA-DRB1 is strongly associated with ACPA levels in ACPA-positive RA, as well as with RA susceptibility. The mechanisms of ACPA production and susceptibility to ACPA-positive RA seem to partly overlap.

The role of growth differentiation factor 15 in the pathogenesis of primary myelofibrosis

Growth differentiation factor 15 (GDF15) is a pleiotropic cytokine that belongs to the transforming growth factor-β superfamily. Elevated serum concentrations of this cytokine have been reported in patients with various malignancies. To assess the potential roles of GDF15 in hematologic malignancies, we measured its serum levels in patients with these diseases. We found that serum GDF15 levels were elevated in almost all these patients, particularly in patients with primary myelofibrosis (PMF). Immunohistochemical staining of bone marrow (BM) specimens revealed that GDF15 was strongly expressed by megakaryocytes, which may be sources of increased serum GDF15 in PMF patients. Therefore, we further assessed the contribution of GDF15 to the pathogenesis of PMF. Recombinant human (rh) GDF15 enhanced the growth of human BM mesenchymal stromal cells (BM-MSCs), and it enhanced the potential of these cells to support human hematopoietic progenitor cell growth in a co-culture system. rhGDF15 enhanced the growth of human primary fibroblasts, but it did not affect their expression of profibrotic genes. rhGDF15 induced osteoblastic differentiation of BM-MSCs in vitro, and pretreatment of BM-MSCs with rGDF15 enhanced the induction of bone formation in a xenograft mouse model. These results suggest that serum levels of GDF15 in PMF are elevated, that megakaryocytes are sources of this cytokine in BM, and that GDF15 may modulate the pathogenesis of PMF by enhancing proliferation and promoting osteogenic differentiation of BM-MSCs.

Accelerated apoptosis of peripheral blood monocytes in Cebpb-deficient mice

The CCAAT/enhancer-binding protein β (C/EBPβ) transcription factor is required for granulopoiesis under stress conditions. However, little is known about its roles in steady state hematopoiesis. Here, we analyzed the peripheral blood and bone marrow of Cebpb(-/-) mice at steady state by flow cytometry and unexpectedly found that the number of peripheral blood monocytes was severely reduced, while the number of bone marrow monocytes was maintained. The ability of Cebpb(-/-) bone marrow cells to give rise to macrophages/monocytes in vitro was comparable to that of wild-type bone marrow cells. Apoptosis of monocytes was enhanced in the peripheral blood, but not in the bone marrow of Cebpb(-/-) mice. These results indicate that C/EBPβ is required for the survival of monocytes in peripheral blood.

Isolation of mesenchymal stromal/stem cells from small-volume umbilical cord blood units that do not qualify for the banking system

The clinical application of mesenchymal stromal/stem cells (MSCs) has been extensively explored. In this study, we examined the availability of freshly donated umbilical cord blood (UCB) units that do not qualify for the Japanese banking system for transplantation because of their small volume as a source of MSCs. Forty-five UCB units were used. The median volume of each UCB unit and number of nucleated cells per unit were 40 mL and 5.39 × 10(8), respectively. MSCs were successfully isolated from 18 of 45 units (40 %). The MSC isolation rate was not affected by cell processing method or the interval between delivery and cell processing. The volume of the UCB unit and the mononuclear cell count were predictive factors of the MSC isolation rate. MSCs were effectively isolated by selecting UCB units with a volume of ≥54 mL and containing ≥1.28 × 10(8) mononuclear cells, yielding a MSC isolation rate of >70 %. UCB-derived MSCs were similar to bone marrow-derived MSCs in terms of their morphology, surface marker expression, and differentiation potential, apart from adipogenesis. Our data indicate that UCB units that are currently discarded due to inadequate volume should be reconsidered as a source of MSCs using the well-established UCB banking system.

Non-steady-state hematopoiesis regulated by the C/EBPβ transcription factor

Steady-state hematopoiesis responds to extracellular stimuli to meet changing demands and also to pathologically altered intracellular signaling. Granulocyte production increases following infection or in response to cytokine stimulation, and activation of the CCAAT/enhancer-binding protein β (C/EBPβ) transcription factor is required for such stress-induced granulopoiesis, whereas C/EBPα plays a critical role in maintaining steady-state granulopoiesis. Different roles of these C/EBP transcription factors in different modes of hematopoiesis are evolutionally conserved from zebrafish to humans. In addition to reactions against infections, C/EBPβ is responsible for cancer-driven myelopoiesis, which promotes cancer progression, at least in part, by abrogating the immune response in the cancer microenvironment. The BCR–ABL fusion protein activates emergency-specific pathway of granulopoiesis by upregulating C/EBPβ. This in turn causes chronic phase chronic myeloid leukemia, which is characterized by myeloid expansion. The C/EBPβ transcription factor also plays a role in other hematological malignancies of both myeloid and lymphoid lineage origin. Thus, elucidation of the upstream and downstream networks surrounding C/EBPβ will lead to the development of novel therapeutic strategies for diseases mediated by non-steady-state hematopoiesis.