Human archetypal pluripotent stem cells differentiate into trophoblast stem cells via endogenous BMP5/7 induction without transitioning through naive state.

Primary human trophoblast stem cells (TSCs) and TSCs derived from human pluripotent stem cells (hPSCs) can potentially model placental processes in vitro. Yet, the pluripotent states and factors involved in the differentiation of hPSCs to TSCs remain poorly understood. In this study, we demonstrate that the primed pluripotent state can generate TSCs by activating pathways such as Epidermal Growth Factor (EGF) and Wingless-related integration site (WNT), and by suppressing tumor growth factor beta (TGFß), histone deacetylases (HDAC), and Rho-associated protein kinase (ROCK) signaling pathways, all without the addition of exogenous Bone morphogenetic protein 4 (BMP4)-a condition we refer to as the TS condition. We characterized this process using temporal single-cell RNA sequencing to compare TS conditions with differentiation protocols involving BMP4 activation alone or BMP4 activation in conjunction with WNT inhibition. The TS condition consistently produced a stable, proliferative cell type that closely mimics first-trimester placental cytotrophoblasts, marked by the activation of endogenous retroviral genes and the absence of amnion expression. This was observed across multiple cell lines, including various primed induced pluripotent stem cell (iPSC) and embryonic stem cell (ESC) lines. Primed-derived TSCs can proliferate for over 30 passages and further specify into multinucleated syncytiotrophoblasts and extravillous trophoblast cells. Our research establishes that the differentiation of primed hPSCs to TSC under TS conditions triggers the induction of TMSB4X, BMP5/7, GATA3, and TFAP2A without progressing through a naive state. These findings propose that the primed hPSC state is part of a continuum of potency with the capacity to differentiate into TSCs through multiple routes.

A case of anti-BP230 antibody-positive bullous pemphigoid receiving DPP-4 inhibitor.

Bullous pemphigoid (BP) is a cutaneous autoimmune blistering disorder. Recently, it has been reported that dipeptidyl peptidase-4 inhibitors (DPP4i) is associated with the development of BP (DPP4i-BP). Patients with DPP4i-BP have autoantibodies (autoAbs) preferentially targeting full-length BP180, but not the BP180NC16a domain. In this report, we described a case of anti-BP230 antibody (Ab)-positive BP receiving DPP4i. A 78-year-old male with a medical history of type 2 diabetes receiving vildagliptin at 100 mg daily for 38 months was referred to our hospital with itching blisters on his body and extremities. Skin biopsy showed subepidermal bulla with eosinophil infiltration. Direct immunofluorescence staining revealed a linear staining pattern with complement C3 and IgG at the subepidermal basement membrane zone. By laboratory testing, autoAbs against BP180NC16a and full-length BP180 were negative by enzyme-linked immunosorbent assay (ELISA); however, anti-BP230 Abs were positive by ELISA (index: 123.91). His HLA genotype was DQB1*04:01 and 05:01. Based on these results, we diagnosed the patient with anti-BP230 Abs-positive BP associated with DPP4i. To the best of our knowledge, this is the first case of DPP4i-BP with only anti-BP230 Abs. Further accumulation of DPP4i-BP cases is needed to clarify the relationship between overall features of DPP4i-BP and anti-BP230 Abs.

BAFF inhibition attenuates fibrosis in scleroderma by modulating the regulatory and effector B cell balance.

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and lung fibrosis. More than 90% of patients with SSc are positive for autoantibodies. In addition, serum B cell activating factor (BAFF) level is correlated with SSc severity and activity. Thus, B cells are considered to play a pathogenic role in SSc. However, there are two opposing subsets: regulatory B cells (Bregs) and effector B cells (Beffs). Interleukin-10 (IL-10)-producing Bregs negatively regulate the immune response, while IL-6-producing Beffs positively regulate it. Therefore, a protocol that selectively depletes Beffs would represent a potent therapy for SSc. The aims of this study were to investigate the roles of Bregs and Beffs in SSc and to provide a scientific basis for developing a new treatment strategy targeting B cells. A bleomycin-induced scleroderma model was induced in mice with a B cell-specific deficiency in IL-6 or IL-10. We also examined whether BAFF regulates cytokine-producing B cells and its effects on the scleroderma model. IL-6-producing Beffs increased in number and infiltrated the inflamed skin in the scleroderma model. The skin and lung fibrosis was attenuated in B cell-specific IL-6-deficient mice, whereas B cell-specific IL-10-deficient mice showed more severe fibrosis. In addition, BAFF increased Beffs but suppressed Bregs. Furthermore, BAFF antagonist attenuated skin and lung fibrosis in the scleroderma model with reduction of Beffs but not of Bregs. The current study indicates that Beffs play a pathogenic role in the scleroderma model, while Bregs play a protective role. BAFF inhibition is a potential therapeutic strategy for SSc via alteration of B cell balance.

S-nitrosylation regulates mitochondrial quality control via activation of parkin.

Parkin, a ubiquitin E3 ligase of the ring between ring fingers family, has been implicated in mitochondrial quality control. A series of recent reports have suggested that the recruitment of parkin is regulated by phosphorylation. However, the molecular mechanism that activates parkin to induce mitochondrial degradation is not well understood. Here, and in contrast to previous reports that S-nitrosylation of parkin is exclusively inhibitory, we identify a previously unrecognized site of S-nitrosylation in parkin (Cys323) that induces mitochondrial degradation. We demonstrate that endogenous S-nitrosylation of parkin is in fact responsible for activation of its E3 ligase activity to induce aggregation and degradation. We further demonstrate that mitochondrial uncoupling agents result in denitrosylation of parkin, and that prevention of denitrosylation restores mitochondrial degradation. Our data indicates that NO both positive effects on mitochondrial quality control, and suggest that targeted S-nitrosylation could provide a novel therapeutic strategy against Parkinson's disease.

Relation of the Glu298Asp polymorphism of the nitric oxide synthase gene to hypertension and serum cholesterol in Japanese workers.

OBJECTIVE: To assess whether the Glu298Asp polymorphism of the endothelial nitric oxide synthase (eNOS) gene possibly mediates the relation of blood pressure and serum cholesterol. METHOD: Regular health examination in 2003 of 1,694 Japanese workers from the Shimane Prefecture, Japan. RESULTS: The frequencies of the Glu/Glu, Glu/Asp, and Asp/Asp genotypes were 85.9%, 13.4%, and 0.7%, respectively. After adjustment for age, sex, BMI, and lifestyle (drinking, smoking, exercise and stress), the odds ratio (OR) of hypertension associated with high (> or = 220 mg/dl or under treatment) total cholesterol was 2.08 (95% Confidence Interval (CI) 1.02-4.24) among carriers of the eNOS 298Asp allele versus 1.18 (95% CI 0.89-1.55, p for interaction=0.50) among non-carriers. Similarly, the ORs of hypertension associated with counseling-need (120-139 mg/dl) and high (> or = 140 mg/dl) levels of LDL cholesterol among carriers of the eNOS 298Asp allele were significantly higher than those among non-carriers, at 2.65 (95% CI 1.16-6.01) versus 1.03 (95% CI 0.77-1.39, p for interaction=0.01), and 2.80 (95% CI 1.33-5.89) versus 0.95 (95% CI 0.71-1.26, p for interaction=0.04), respectively. CONCLUSION: These results indicate that the eNOS 298Asp allele, which is weakly associated with hypertension, may increase the risk of hypertension when associated with high serum lipid levels.