GWAS for systemic sclerosis identifies six novel susceptibility loci including one in the Fcγ receptor region

Here we report the largest Asian genome-wide association study (GWAS) for systemic sclerosis performed to date, based on data from Japanese subjects and comprising of 1428 cases and 112,599 controls. The lead SNP is in the FCGR/FCRL region, which shows a penetrating association in the Asian population, while a complete linkage disequilibrium SNP, rs10917688, is found in a cis-regulatory element for IRF8. IRF8 is also a significant locus in European GWAS for systemic sclerosis, but rs10917688 only shows an association in the presence of the risk allele of IRF8 in the Japanese population. Further analysis shows that rs10917688 is marked with H3K4me1 in primary B cells. A meta-analysis with a European GWAS detects 30 additional significant loci. Polygenic risk scores constructed with the effect sizes of the meta-analysis suggest the potential portability of genetic associations beyond populations. Prioritizing the top 5% of SNPs of IRF8 binding sites in B cells improves the fitting of the polygenic risk scores, underscoring the roles of B cells and IRF8 in the development of systemic sclerosis. The results also suggest that systemic sclerosis shares a common genetic architecture across populations.

Impact of body mass index on the severity of bexarotene-associated hypertriglyceridemia: A post hoc analysis of an open-labeled clinical study of combined bexarotene and phototherapy in Japanese patients with cutaneous T-cell lymphoma

Bexarotene is an effective oral drug for the treatment of cutaneous T-cell lymphoma, but careful management is required due to its various side effects. In particular, hypertriglyceridemia often requires a reduction or even suspension of bexarotene therapy. The risk factors of bexarotene-associated severe hypertriglyceridemia are not clear. Here, we conducted a post hoc analysis of the data from our previous clinical trial, which confirmed the efficacy and safety of combined bexarotene and phototherapy, to evaluate the effect of body mass index on bexarotene-associated hypertriglyceridemia. Twenty-five subjects were divided into two subgroups: normal and underweight (body mass index [BMI] <25 kg/m² group) and overweight and obese (BMI ≥25 kg/m² group) patients. The overall incidence of hypertriglyceridemia was 81.3% (13/16) in the BMI <25 kg/m² group and 88.9% (8/9) in the BMI ≥25 kg/m² group. The incidence of grade ≥3 hypertriglyceridemia (≥500 mg/dL) was 7.7% (1/13) in the BMI <25 kg/m² group and 7/8 (87.5%) in the BMI ≥25 kg/m² group (P < 0.001). Consequently, dose reduction in the BMI ≥25 kg/m² group was larger than that in the BMI <25 kg/m² group. The bexarotene-induced change in the serum triglyceride concentration was significantly increased in cutaneous T-cell lymphoma patients with a higher body mass index (ρ = 0.508, P = 0.009). The area under the curve was 0.886 (95% confidence interval 0.748-1.000, P = 0.002). With a body mass index cut-off of 24.85 kg/m² , the sensitivity and specificity for identifying grade ≥3 hypertriglyceridemia were 0.875 and 0.882, respectively. The present findings suggest that BMI ≥25 kg/m² is a risk factor for bexarotene-associated severe hypertriglyceridemia, therefore overweight and obese patients treated with bexarotene should receive lipid-lowering drugs prophylactically. Further studies for optimizing the initial bexarotene dose in such patients are required.

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

Autoinflammatory Keratinization Disease With Hepatitis and Autism Reveals Roles for JAK1 Kinase Hyperactivity in Autoinflammation

Heterozygous mutations in JAK1 which result in JAK-STAT hyperactivity have been implicated in an autosomal dominant disorder that features multi-organ immune dysregulation. This study identifies another previously unreported heterozygous missense JAK1 mutation, H596D, in an individual with a unique autoinflammatory keratinization disease associated with early-onset liver dysfunction and autism. Using CRISPR-Cas9 gene targeting, we generated mice with an identical Jak1 knock-in missense mutation (Jak1^{H595D/+;I596I/+;Y597Y/+} mice) that recapitulated key aspects of the human phenotype. RNA sequencing of samples isolated from the Jak1^{H595D/+;I596I/+;Y597Y/+} mice revealed the upregulation of genes associated with the hyperactivation of tyrosine kinases and NF-κB signaling. Interestingly, there was a strong correlation between genes downregulated in Jak1^{H595D/+;I596I/+;Y597Y/+} mice and those downregulated in the brain of model mice with 22q11.2 deletion syndrome that showed cognitive and behavioral deficits, such as autism spectrum disorders. Our findings expand the phenotypic spectrum of JAK1-associated disease and underscore how JAK1 dysfunction contributes to this autoinflammatory disorder.

Comparison of the Efficacy and Safety of Bexarotene and Photo(Chemo)Therapy Combination Therapy and Bexarotene Monotherapy for Cutaneous T-Cell Lymphoma

Introduction

Cutaneous T-cell lymphoma (CTCL) is a chronic condition with low malignancy. The combined use of therapeutic agents and photo(chemo)therapy is widely applied for the treatment of CTCL. The efficacy and safety of bexarotene and photo(chemo)therapy combination therapy were previously confirmed in Japanese patients with CTCL. The efficacy and safety of the bexarotene and photo(chemo)therapy combination therapy was compared with bexarotene monotherapy in Japanese patients with CTCL.

Methods

This was a randomized, open-label, two-parallel-group, active-control specified clinical study in Japanese patients diagnosed with CTCL carried out over 8 weeks with a study extension conducted at two institutions. This study was registered in Japan Registry of Clinical Trials (jRCTs041180094).

Results

In the combination therapy group, 22 subjects received oral bexarotene (300 mg/m² body surface area) once daily, followed by bath-psoralen and ultraviolet (UV) A or narrowband UVB. In the monotherapy group, 24 subjects received oral bexarotene (300 mg/m²) once daily. The efficacy analysis using the modified Severity-Weighted Assessment Tool, which included 39 patients, showed a response rate of 81.0% (17/21) in the combination therapy group and 83.3% (15/18) in the monotherapy group. No statistically significant difference was detected between groups. In the combination therapy group, four subjects showed a complete clinical response or complete response, and subjects with a partial response exhibited a high rate of skin lesion resolution, significantly better than in the monotherapy group. In the safety analysis, which included 46 treated subjects (22 in the combination therapy group and 24 in the monotherapy group), no adverse events or adverse drug reactions were reported in either group.

Conclusion

Both bexarotene and photo(chemo)therapy combination therapy and bexarotene monotherapy were therapeutically effective in Japanese patients with CTCL and well tolerated. Combination therapy led to a higher skin lesion resolution rate and greater therapeutic effects compared with monotherapy.

Trial Registration

jRCTs041180094.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-021-00655-0.

This study evaluated the efficacy and safety of bexarotene monotherapy compared with bexarotene and photo(chemo)therapy combination therapy in Japanese patients with cutaneous T-cell lymphoma (CTCL). The study was a randomized, open-label, two-parallel-group, active-control specified clinical study in patients diagnosed with CTCL performed over an 8-week period with a study extension conducted in two institutions. In the combination therapy group, bexarotene (300 mg/m² body surface area) was administered orally once daily to 22 subjects, followed by treatment with bath-psoralen and ultraviolet A (bath-PUVA) or narrowband UVB. In the bexarotene monotherapy group, bexarotene (300 mg/m²) was administered orally once daily to 24 subjects. Efficacy was assessed using the modified Severity-Weighted Assessment Tool. Among the 39 subjects analyzed for treatment efficacy, the response rate of the combination therapy group was 81.0% (17/21) and that of the monotherapy group was 83.3% (15/18). Differences between the two treatment groups were not statistically significant. Of the 21 subjects in the combination therapy group, 4 had a complete clinical response or complete response, and those with a partial response showed a higher skin lesion resolution rate than in the monotherapy group. The safety analysis revealed no reports of adverse events or adverse drug reactions among the 46 treated subjects (combination therapy group = 22; monotherapy group = 24). Thus, both bexarotene and photo(chemo)therapy combination therapy and bexarotene monotherapy were therapeutically effective and well tolerated in Japanese patients with CTCL. Patients receiving the combined therapy, however, showed a higher rate of skin lesion resolution.

Effect of adalimumab on axial manifestations in Japanese patients with psoriatic arthritis: a 24 week prospective, observational study

OBJECTIVES

PsA is characterized by enthesitis, synovitis and osseous involvement in the peripheral and axial joints. Few studies have examined axial involvement in PsA using imaging techniques. Here we examined axial involvement in PsA patients using MRI. In addition, we determined the efficacy of 24 week adalimumab treatment in improving the MRI findings of spondylitis and sacroiliitis.

METHODS

This was a prospective, open-label, single-arm study in patients with PsA. Adalimumab was administered to patients for a total of 24 weeks. MRI examinations were conducted at baseline and at week 24 of adalimumab treatment.

RESULTS

Thirty-seven patients with PsA were included in this study. Spondylitis was observed in at least one site of the positive scan in 91% (n = 31) of patients with PsA. The number of arthritic sites in the cervical, thoracic and lumbar regions of the spine was 48, 67 and 53, respectively. All patients had MRI-determined sacroiliitis of grade ≥1 severity while 28 patients (82%) had grade ≥2 sacroiliitis in at least one sacroiliac region. Sacroiliac arthritis was statistically more severe on the right side than on the left side (P < 0.05). In 34 patients with PsA, the thoracic spine was the most common site of spondylitis. In addition, 24 week adalimumab treatment led to an improvement in the mean number of spondylitis sites and the mean grade of sacroiliitis.

CONCLUSION

Treatment with adalimumab for 24 weeks resulted in improvement in spondylitis and sacroiliitis.

Efficacy of bath-psoralen and ultraviolet A therapy for mycosis fungoides - retrospective analysis of 62 cases

Photochemotherapy with psoralen and ultraviolet A (PUVA) is widely used for refractory skin diseases. Bathwater delivery of 8‐methoxypsoralen (8‐MOPS) with subsequent UVA irradiation (bath‐PUVA) or oral administration of 8‐MOPS with UVA is used to treat mycosis fungoides. We retrospectively analyzed 62 patients with mycosis fungoides (8 stage IA, 30 stage IB, 5 stage IIB, 18 stage IIIA, and 1 stage IVA2) treated with bath‐PUVA at the Dermatology Clinic of Nagoya City University Hospital from November 2004 to December 2013. A complete response was achieved in 37 (59.7%) patients, a partial response was achieved in 16 (25.8%), and stable disease was achieved in 6 (9.7%). Progressive disease was observed in 3 (4.8%) patients. Almost all patients in stage IA/IB achieved a complete response. Of the 5 stage IIB patients, 2 achieved a partial response, 1 achieved stable disease, and 2 had progressive disease. The serum concentrations of soluble interleukin‐2 receptor and lactate dehydrogenase decreased significantly following treatment with bath‐PUVA (p < 0.001). We examined the risk factors of patients whose stage progressed despite PUVA treatment. A multivariate Cox regression analysis of risk factors associated with stage progression yielded a hazard ratio of 28.5 for stage IIb. Treatment with bath‐PUVA is highly effective in the early stages of mycosis fungoides, and partially effective in advanced stages.

Gender disparities in academic dermatology in Japan: Results from the first national survey

BACKGROUND

A wide gender gap exists in many fields in Japan, including the academic society of dermatology. Women are substantially underrepresented in the highest academic ranks.

OBJECTIVE

We aimed to clarify the possible factors contributing to the current gender gap in the field of academic dermatology and to recommend necessary measures to decrease the gender gap.

METHODS

We performed a cross-sectional study of faculty members' academic productivity at the dermatology departments of all the educational institutions in Japan in 2019.

RESULTS

Women had significantly lower academic productivity than men. A significant gender difference in academic productivity was found in lecturers and assistant professors but not in associate professor and professor positions. This gender difference was still significant after normalizing the productivity for career length.

CONCLUSION

Our findings suggest the need to encourage women lecturers and assistant professors to improve their academic achievement to decrease the gender gap in academic dermatology.

Combination immunosuppressant therapy for rapidly progressive pyoderma gangrenosum in a child

An 8-year-old girl was presented to our clinic with fever, arthritis in her left knee, a necrotic right fifth toe, and multiple large deep-seated ulcerations. She was diagnosed with pyoderma gangrenosum. Treatment with corticosteroids alone was ineffective for her skin lesions, and therefore combination immunosuppressant therapy was administered. Her skin lesions rapidly improved, enabling discontinuation of the corticosteroid therapy and avoiding systemic infection through the ulcers. Combination immunosuppressant therapy may be a treatment option for patients with severe, rapidly progressive pyoderma gangrenosum.

Exploration of biomarkers to predict clinical improvement of atopic dermatitis in patients treated with dupilumab: A study protocol

BACKGROUND

Atopic dermatitis (AD) is a common eczematous skin disorder that profoundly reduces the quality of life due to intractable pruritus. Excellent therapeutic success of the anti-interleukin 4 receptor-α antibody dupilumab in clinical trials and a real-world clinical context indicates the crucial roles of interleukin (IL)-4 and IL-13 in the pathogenesis of AD. Along with the clinical improvement in skin scores and pruritus, dupilumab significantly and progressively reduces and normalizes the upregulated expression of T helper type 2 signatures such as Chemokine (C-C motif) ligand (CCL)17, CCL18, CCL22, and CCL26 in the lesional skin of AD. However, no blood/serum biomarkers are known to predict good or poor outcome in patients with AD treated with dupilumab.

METHODS

Patients are at least 18 years of age and have moderate-to-severe AD with Eczema Area and Severity Index (EASI) ≥16, Investigator's Global Assessment ≥3, and body surface area ≥10%. We are going to enroll more than 130 subjects from 18 medical facilities. Clinical objective findings will be evaluated by EASI. Subjective symptoms will be assessed by Patient-Oriented Eczema Measure, Numerical Rating Scale for Pruritus (Pruritus-NRS), Skin Comfort-NRS, and Treatment Satisfaction-NRS. We will measure 18 blood/serum biomarkers including % eosinophils in blood cell count, lactate dehydrogenase, total IgE, soluble interleukin 2 receptor, CCL17, CCL18, CCL22, CCL26, CCL27, IL-13, IL-22, IL-24, IL-25, IL-31, IL-33, thymic stromal lymphopoietin, periostin, and squamous cell carcinoma antigen-2. The clinical evaluation and biomarker sampling will be performed at 0, 2, 4, 8, and 16 weeks of dupilumab treatment. We will also perform proteomic analysis (of roughly 300 proteins) of the patients' sera obtained at 0 and 2 weeks of treatment. The primary endpoint is the association between "baseline levels of 18 biomarkers" and "% change from baseline of EASI at 16 weeks of dupilumab treatment."

DISCUSSION

This is the first clinical trial to explore the biomarkers, including potential proteomic markers, most strongly associated with improvement in EASI in patients with moderate-to-severe AD treated with dupilumab for 16 weeks (B-PAD study). A limitation is that we will only enroll Japanese patients.

Ultraviolet A1 phototherapy for the treatment of localized scleroderma

Ultraviolet (UV)A1 phototherapy is effective for T-cell-mediated skin diseases such as atopic dermatitis and mast cell-mediated skin diseases such as mastocytoma. UVA1 phototherapy is also effective against the sclerotic lesions of systemic sclerosis and morphea. Currently, in Japan, access to UVA1 phototherapy is limited because the UVA1 phototherapy device has not yet been approved. On the basis of our experience, we report three patients with localized scleroderma who responded successfully to UVA1 phototherapy. Efficacy was assessed by histological analysis and elastography. UVA1 successfully ameliorated sclerotic lesions, including morphea, linear scleroderma and morphea lesions in a patient with limited cutaneous systemic sclerosis. No side-effects were observed during UVA1 phototherapy.

Efficacy and safety of bexarotene combined with photo(chemo)therapy for cutaneous T-cell lymphoma

Cutaneous T‐cell lymphoma (CTCL) is a chronic condition with low malignancy. International treatment guidelines for CTCL are widely followed in Europe and the USA. Combination therapy with therapeutic agents for CTCL and phototherapy is effective on the basis of European data. The efficacy and safety of combination therapy for Japanese CTCL patients are not established. We investigated the efficacy and safety of combination therapy with photo(chemo)therapy and bexarotene in Japanese CTCL patients. Twenty‐five patients received daily oral bexarotene (300 mg/m² body surface), followed by bath‐psoralen plus ultraviolet (UV)‐A (PUVA) or narrowband UV‐B. Treatment results were evaluated using the modified Severity‐Weighted Assessment Tool (mSWAT) and the Physician Global Assessment of Clinical Condition (PGA) up to week 24. Safety was also assessed. Twenty‐four weeks after initiating treatment, the total response rate was 80.0% (mSWAT) and 84.0% (PGA). Response rates did not differ when stratified by disease stage. Number of days (mean ± standard deviation) for time to response, duration of response and time to progression determined by the mSWAT were 20.7 ± 9.62, 117.0 ± 43.0 and 163.6 ± 28.8, respectively. T‐helper 2 chemokine levels in patients at stage IIA or more decreased significantly at weeks 12 and 24. All patients experienced adverse events and adverse drug reactions. Serious adverse drug reactions included sepsis, anemia and congestive cardiac insufficiency (n = 1 each). Other adverse drug reactions were of mild to moderate severity. Combination therapy with bexarotene and PUVA was safe and effective in Japanese CTCL patients.

Hyperglycemia Is Associated with Psoriatic Inflammation in Both Humans and Mice

Chronic low-grade inflammation can cause several metabolic syndromes. Patients with psoriasis, a chronic immunological skin inflammation, often develop diabetes. However, it is not clear to date how psoriasis leads to, or is correlated with, glucose intolerance. Here, we investigate whether psoriasis itself is correlated with hyperglycemia in humans and mice. In patients, the severity of psoriasis was correlated with high blood glucose levels, and treatment of psoriasis by phototherapy improved insulin secretion. Imiquimod-induced systemic and cutaneous inflammation in mice, with features of human psoriasis, also resulted in hyperglycemia. Although it should be determined if psoriasis-like cutaneous inflammation alone can induce hyperglycemia, imiquimod-treated mice showed impairment of insulin secretion without significant islet inflammation. Administration of anti-IL-17A monoclonal antibody improved hyperglycemia in patients with psoriasis and imiquimod-treated mice with psoriasiform features. These results suggest that hyperglycemia is highly associated with psoriasis, mainly through IL-17.

Case of epidermolysis bullosa acquisita with concomitant anti-laminin-332 antibodies

Subepidermal autoimmune blistering disease including bullous pemphigoid, pemphigoid gestationis, mucous membrane pemphigoid, anti-laminin-γ1 pemphigoid, linear immunoglobulin A bullous disease and epidermolysis bullosa acquisita (EBA), are all characterized by direct immunofluorescence microscopy or immunoglobulin deposition on the basement membrane zone. Among them, EBA is a rare acquired subepidermal autoimmune blistering disease of the skin and mucous membranes reactive with type VII collagen, a major component of the epidermal basement membrane zone. Anti-laminin-332-type mucous membrane pemphigoid has pathogenic autoantibodies against laminin-332, which is a basement membrane heterotrimeric protein composed of α3, β3 and γ2 laminin chains. We describe a 73-year-old Japanese man presenting with multiple, annular, tense blisters on the lower legs and oral lesions. Despite the severe clinical manifestations, the disease was successfully controlled by combination therapy of oral prednisolone and mizoribine. This case was confirmed to have autoantibodies to both type VII collagen and laminin-332 α3 chain by indirect immunofluorescence of 1 mol NaCl-split normal human skin, various immunoblot analyses and enzyme-linked immunosorbent assays. This case was a rare case of EBA with concomitant anti-laminin-332 antibodies.

Assessment of medication adherence and treatment satisfaction in Japanese patients with psoriasis of various severities

Psoriasis is a chronic, relapsing, inflammatory keratotic skin disease. To elucidate the medication adherence and treatment satisfaction, we performed a questionnaire survey using the eight-item Morisky Medication Adherence Scale (MMAS-8) and nine-item Treatment Satisfaction Questionnaire for Medication (TSQM-9) of 163 psoriatic patients who regularly visited hospitals or clinics. To assess the relationship between the MMAS-8/TSQM-9 outcomes and severity of psoriasis, two different clinical severity indices were used: the Psoriasis Area and the Severity Index (PASI) for disease severity and the Psoriasis Disability Index (PDI) for quality of life (QOL) impairment. The MMAS-8 score for oral medication was significantly higher than that for topical medication. The oral and topical MMAS-8 scores were significantly correlated with the PDI score, but not with the PASI score, indicating that QOL impairment lowered treatment motivation. All of the TSQM-9 domain scores (effectiveness, convenience and global satisfaction) were significantly correlated with both the PASI and PDI scores, suggesting that patients whose skin and QOL conditions were under good control had high satisfaction with treatment. Patients treated with biologics had higher satisfaction than those treated with non-biologics.

[Survey on Information Sharing and Approaches to Cooperation between Hospitals and Community Pharmacies in the Care of Outpatients Receiving Chemotherapy]

Outpatients undergoing chemotherapy receive oral anticancer drugs, supportive care medicine, and drugs for complications from health insurance pharmacies(ie, drugstores). Therefore, drugstore personnel and patients were surveyed using a questionnaire to ascertain the current conditions of information sharing between drugstores and hospitals. Only 31% of the patients surveyed responded that they received cancer chemotherapy via the drugstores, while a few of them understood the need for information sharing with the drugstore. We also found that the drugstores required a considerable amount of patient information including prescribed therapeutic drugs, treatment regimens, disease conditions, and test value. Therefore, we held a study session and clinical conference to facilitate the creation of an information-sharing system. In conclusion, it is imperative for drugstores and hospitals to cooperate and establish a strategy for information sharing in the future.

Action spectrum of melanoblast maturation and involvement of the aryl hydrocarbon receptor

The aryl hydrocarbon receptor (AHR) mediates melanocyte activation and skin tanning. We hypothesized that the AHR also mediates melanoblast-to-melanocyte maturation. In a cloned cell line, NCCmelb4, derived from mouse neural crest cells, we investigated AHR expression in melanoblasts stimulated by UV irradiation and AHR agonists. We irradiated the cells with UV, ranging from 280 to 380 nm in 10-nm increments, using a multiwavelength irradiation spectral apparatus. Tyrosinase expression significantly increased with bimodal peaks at 310 and 360 nm. Although melanoblast activation peaked 48 hours after irradiation, the most suitable irradiation interval was 24 hours. AHR expression significantly increased at 360 nm, but not at 310 nm. The AHR agonist, VAF347, and water-soluble tobacco smoke extract induced melanoblast maturation and AHR activation. The culture supernatant derived from the NS47 fibroblast cell line also induced melanoblast maturation and AHR activation. These findings suggest that UV and environmental stimulation of melanoblast-to-melanocyte maturation are enhanced via the AHR pathway.

Periodontal tissue engineering by nano beta-tricalcium phosphate scaffold and fibroblast growth factor-2 in one-wall infrabony defects of dogs

BACKGROUND AND OBJECTIVE

Nanoparticle bioceramics are being investigated for biomedical applications. We fabricated a regenerative scaffold comprising type I collagen and beta-tricalcium phosphate (β-TCP) nanoparticles. Fibroblast growth factor-2 (FGF-2) is a bioeffective signaling molecule that stimulates cell proliferation and wound healing. This study examined the effects, on bioactivity, of a nano-β-TCP/collagen scaffold loaded with FGF-2, particularly on periodontal tissue wound healing.

MATERIAL AND METHODS

Beta-tricalcium phosphate was pulverized into nanosize particles (84 nm) and was then dispersed. A nano-β-TCP scaffold was prepared by coating the surface of a collagen scaffold with a nanosize β-TCP dispersion. Scaffolds were characterized using scanning electron microscopy, compressive testing, cell seeding and rat subcutaneous implant testing. Then, nano-β-TCP scaffold, nano-β-TCP scaffold loaded with FGF-2 and noncoated collagen scaffold were implanted into a dog one-wall infrabony defect model. Histological observations were made at 10 d and 4 wk postsurgery.

RESULTS

Scanning electron microscopy images show that TCP nanoparticles were attached to collagen fibers. The nano-β-TCP scaffold showed higher compressive strength and cytocompatibility compared with the noncoated collagen scaffold. Rat subcutaneous implant tests showed that the DNA contents of infiltrating cells in the nano-β-TCP scaffold and the FGF-2-loaded scaffold were approximately 2.8-fold and 3.7-fold greater, respectively, than in the collagen scaffold. Histological samples from the periodontal defect model showed about five-fold greater periodontal tissue repair following implantation of the nano-β-TCP scaffold loaded with FGF-2 compared with the collagen scaffold.

CONCLUSION

The β-TCP nanoparticle coating strongly improved the collagen scaffold bioactivity. Nano-β-TCP scaffolds containing FGF-2 are anticipated for use in periodontal tissue engineering.

Site-specific migration of human fetal melanocytes in volar skin

BACKGROUND

Melanocytes originate from the neural crest and migrate ventrally from the dorsal neural tube during embryogenesis. How human melanocytes locate at their suitable positions during embryogenesis, however, is unclear. Although a growing body of evidence indicates that melanocytes, melanoblasts, and melanocyte stem cells are closely related to hair follicles, little is known about volar skin.

OBJECTIVE

The aim of this study was to observe skin development during human fetal period and clarify the site-specific migration process of human fetal sole melanocytes.

METHODS

We obtained 4-mm punch biopsies from the scalp, back, abdomen, and right sole of 36 aborted fetuses (gestational age 12-21 weeks). We compared the migration process between hairly areas and volar areas by immunohistochemical staining.

RESULTS

Immunohistochemical examination revealed that gp100 (HMB-45) sensitively detects human melanocytes in embryogenesis. Melanocytes were present at the epidermal base, where hair placodes/buds form at 12-15 weeks gestation. Fetal melanocytes in hair follicles are supplied from the epidermis. In volar skin, melanocytes originally localize only in the acrosyringium, where they migrate deeper into with gland development at 16-18 weeks gestation. Palmoplantar melanocyte migration and maturation processes differ considerably from those of the other hairy skin sites.

CONCLUSION

Eccrine sweat glands seem to have a central role in the palmoplantar melanocyte migration process, similar to the role of hair follicles in hairy sites.

Bone augmentation using a highly porous PLGA/β-TCP scaffold containing fibroblast growth factor-2

BACKGROUND AND OBJECTIVE

Beta-tricalcium phosphate (β-TCP), a bio-absorbable ceramic, facilitates bone conductivity. We constructed a highly porous three-dimensional scaffold, using β-TCP, for bone tissue engineering and coated it with co-poly lactic acid/glycolic acid (PLGA) to improve the mechanical strength and biological performance. The aim of this study was to examine the effect of implantation of the PLGA/β-TCP scaffold loaded with fibroblast growth factor-2 (FGF-2) on bone augmentation.

MATERIAL AND METHODS

The β-TCP scaffold was fabricated by the replica method using polyurethane foam, then coated with PLGA. The PLGA/β-TCP scaffold was characterized by scanning electron miscroscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction, compressive testing, cell culture and a subcutaneous implant test. Subsequently, a bone-forming test was performed using 52 rats. The β-TCP scaffold, PLGA-coated scaffold, and β-TCP and PLGA-coated scaffolds loaded with FGF-2, were implanted into rat cranial bone. Histological observations were made at 10 and 35 d postsurgery.

RESULTS

SEM and TEM observations showed a thin PLGA layer on the β-TCP particles after coating. High porosity (> 90%) of the scaffold was exhibited after PLGA coating, and the compressive strength of the PLGA/β-TCP scaffold was six-fold greater than that of the noncoated scaffold. Good biocompatibility of the PLGA/β-TCP scaffold was found in the culture and implant tests. Histological samples obtained following implantation of PLGA/β-TCP scaffold loaded with FGF-2 showed significant bone augmentation.

CONCLUSION

The PLGA coating improved the mechanical strength of β-TCP scaffolds while maintaining high porosity and tissue compatibility. PLGA/β-TCP scaffolds, in combination with FGF-2, are bioeffective for bone augmentation.

Novel CD3-specific antibody induces immunosuppression via impaired phosphorylation of LAT and PLCγ1 following T-cell stimulation

The activation of T cells is known to be accompanied by the temporary downmodulation of the TCR/CD3 complex on the cell surface. Here, we established a novel monoclonal antibody, Dow2, that temporarily induces downmodulation of the TCR/CD3 complex in mouse CD4(+) T cells without activating T cells. Dow2 recognized the determinant on CD3ε; however, differences were observed in the binding mode between Dow2 and the agonistic anti-CD3ε Ab, 145-2C11. An injection of Dow2 in vivo resulted in T-cell anergy, and prolonged the survival of cardiac allografts without a marked increase in cytokine release. The phosphorylated forms of the signaling proteins PLC-γ1 and LAT in Dow2-induced anergic T cells were markedly decreased upon stimulation. However, the levels of phosphorylated LAT and PLCγ1 in Dow2-induced anergic T cells could be rescued in the presence of the proteasome inhibitor MG-132. These results suggest that proteasome-mediated degradation is involved in hypophosphorylated LAT and PLCγ1 in Dow2-induced anergic T cells. The novel CD3-specific Ab, Dow2, may provide us with a unique tool for inducing immunosuppression.

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gμ below 10(-8) in some regions of the cosmic string parameter space.

Role of the aryl hydrocarbon receptor in tobacco smoke extract-induced matrix metalloproteinase-1 expression

Findings from large epidemiologic studies indicate that there is a link between smoking and extrinsic skin ageing. We previously reported that matrix metalloproteinases (MMPs) mediate connective tissue damage in skin exposed to tobacco smoke extracts. Tobacco smoke contains more than 3800 constituents, including numerous water-insoluble polycyclic aromatic hydrocarbons (PAHs) that trigger aryl hydrocarbon receptor (AhR) signalling pathways. To analyse the molecular mechanisms involved in tobacco smoke-induced skin ageing, we exposed primary human fibroblasts and keratinocytes to tobacco smoke extracts. Hexane- and water-soluble tobacco smoke extracts significantly induced MMP-1 mRNA in both human cultured fibroblasts and keratinocytes in a dose-dependent manner. To clarify the involvement of the AhR pathway, we used a stable AhR-knockdown HaCaT cell line. AhR knockdown abolished the increased transcription of the AhR-dependent genes CYP1A1/CYP1B1 and MMP-1 induced by either of the tobacco smoke extracts. Furthermore, the tobacco smoke extracts induced 7-ethoxyresorufin-O-deethylase activity, which was almost completely abolished by AhR knockdown. Likewise, treating fibroblasts with AhR pathway inhibitors, that is, the flavonoids 3-methoxy-4-nitroflavone and α-naphthoflavone, blocked the expression of CYP1B1 and MMP-1. These findings suggest that the tobacco smoke extracts induce MMP-1 expression in human fibroblasts and keratinocytes via activation of the AhR pathway. Thus, the AhR pathway may be pathogenetically involved in extrinsic skin ageing.