Genetic determinants of obesity in Korean populations: exploring genome-wide associations and polygenic risk scores.

East Asian populations exhibit a genetic predisposition to obesity, yet comprehensive research on these traits is limited. We conducted a genome-wide association study (GWAS) with 93,673 Korean subjects to uncover novel genetic loci linked to obesity, examining metrics such as body mass index, waist circumference, body fat ratio, and abdominal fat ratio. Participants were categorized into non-obese, metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO) groups. Using advanced computational methods, we developed a multifaceted polygenic risk scores (PRS) model to predict obesity. Our GWAS identified significant genetic effects with distinct sizes and directions within the MHO and MUO groups compared with the non-obese group. Gene-based and gene-set analyses, along with cluster analysis, revealed heterogeneous patterns of significant genes on chromosomes 3 (MUO group) and 11 (MHO group). In analyses targeting genetic predisposition differences based on metabolic health, odds ratios of high PRS compared with medium PRS showed significant differences between non-obese and MUO, and non-obese and MHO. Similar patterns were seen for low PRS compared with medium PRS. These findings were supported by the estimated genetic correlation (0.89 from bivariate GREML). Regional analyses highlighted significant local genetic correlations on chromosome 11, while single variant approaches suggested widespread pleiotropic effects, especially on chromosome 11. In conclusion, our study identifies specific genetic loci and risks associated with obesity in the Korean population, emphasizing the heterogeneous genetic factors contributing to MHO and MUO.

Genotypic Heterogeneity of Orientia tsutsugamushi in Scrub Typhus Patients and Thrombocytopenia Syndrome Co-infection, Myanmar.

Serologic and molecular surveillance of serum collected from 152 suspected scrub typhus patients in Myanmar revealed Orientia tsutsugamushi of genotypic heterogeneity. In addition, potential co-infection with severe fever with thrombocytopenia syndrome virus was observed in 5 (3.3%) patients. Both scrub typhus and severe fever with thrombocytopenia syndrome are endemic in Myanmar.

Effects of gemfibrozil on sex hormones and reproduction related performances of Oryzias latipes following long-term (155 d) and short-term (21 d) exposure.

Gemfibrozil, a lipid-regulating pharmaceutical, has been widely used for treating dyslipidemia in humans and detected frequently in freshwater environments. Since plasma cholesterol is a precursor of steroid hormones, the use of gemfibrozil may influence the sex hormone balances. However, its endocrine toxicity following long-term exposure is not well understood. The purpose of the present study is to investigate the effects of gemfibrozil on sex hormones and reproductive outcomes in a freshwater fish, following a long-term (155 d) exposure. For this purpose, Japanese medaka embryos (F0) were exposed to a series of gemfibrozil concentrations, i.e., 0, 0.04, 0.4, 3.7, and 40 mg/L for 155 d, and reproductive parameters, sex hormones, and associated gene expressions were assessed. For comparison, a short-term exposure (21 d) was performed separately with adult medaka and measured for sex hormones and related gene expressions. Following the 155 d long-term exposure, the fecundity showed a decreasing pattern. In addition, at 3.7 mg/L gemfibrozil, testosterone (T) level in the female fish was significantly decreased, and the hatchability of F1 fish was significantly decreased. The estrogen receptor (er) or vitellogenin (vtg) genes in gonads and liver were up-regulated. However, plasma cholesterol levels did not show significant changes in both sexes. The observations from the short-term (21 d) exposure were different from those of the long-term exposure. Following the short-term exposure, decreased 17ß-estradiol (E2), and 11-ketotestosterone (11-KT) levels along with decrease plasma cholesterol were observed in the male fish. The hormone disruption following the short-term exposure appears to be associated with the hypocholesterolemic activity of gemfibrozil. Our results show that the mechanisms of gemfibrozil toxicity may depend on the exposure duration. Consequences of long-term exposure to other fibrates in the water environment warrant further investigations.

The Specific Morphological Features of Alveolar Bone.

OBJECTIVE: The aim of the study was to study the specific morphological features of alveolar bone and compare it to femoral bone in rats. METHODS: Twelve 3-month-old nonpregnant female Sprague-Dawley rats were used in the present study. The left maxillae and femurs of 6 rats were used for micro-computed tomography (micro-CT) scanning. The trabecular bone of the distal femur and the interradicular alveolar bone of the maxillary first molar were reconstructed and analyzed. Another 6 rats were used for histological analysis of trabecular bone and alveolar bone. RESULTS: Micro-CT analysis suggested that the femoral trabecular bone was porous with rod-like trabeculae with a scattered distribution in bone marrow, whereas alveolar bone showed a compact structure with plate-like trabeculae and limited bone marrow. Tissue mineral density, bone mineral density, bone volume fraction, and trabecular thickness were dramatically higher in the alveolar bone compared with that in the trabecular bone. Alveolar bone displayed lower trabecular number and trabecular separation. Histomorphometric analysis showed that alveolar bone was formed of compact bone with wide trabeculae, whereas femurs were composed of loose bone with finer trabeculae. CONCLUSIONS: In comparison to the spongiosa of the distal femur, alveolar bone displays specific morphological features with compact, wide, and highly mineralized trabeculae.

Casein Kinase 2 (CK2)-mediated Phosphorylation of Hsp90ß as a Novel Mechanism of Rifampin-induced MDR1 Expression.

The P-glycoprotein (P-gp) encoded by the MDR1 gene is a drug-exporting transporter located in the cellular membrane. P-gp induction is regarded as one of the main mechanisms underlying drug-induced resistance. Although there is great interest in the regulation of P-gp expression, little is known about its underlying regulatory mechanisms. In this study, we demonstrate that casein kinase 2 (CK2)-mediated phosphorylation of heat shock protein 90ß (Hsp90ß) and subsequent stabilization of PXR is a key mechanism in the regulation of MDR1 expression. Furthermore, we show that CK2 is directly activated by rifampin. Upon exposure to rifampin, CK2 catalyzes the phosphorylation of Hsp90ß at the Ser-225/254 residues. Phosphorylated Hsp90ß then interacts with PXR, causing a subsequent increase in its stability, leading to the induction of P-gp expression. In addition, inhibition of CK2 and Hsp90ß enhances the down-regulation of PXR and P-gp expression. The results of this study may facilitate the development of new strategies to prevent multidrug resistance and provide a plausible mechanism for acquired drug resistance by CK2-mediated regulation of P-gp expression.

Generation of protective immunity against Orientia tsutsugamushi infection by immunization with a zinc oxide nanoparticle combined with ScaA antigen.

BACKGROUND: Zinc oxide nanoparticle (ZNP) has been applied in various biomedical fields. Here, we investigated the usage of ZNP as an antigen carrier for vaccine development by combining a high affinity peptide to ZNP. RESULTS: A novel zinc oxide-binding peptide (ZBP), FPYPGGDA, with high affinity to ZNP (K a  = 2.26 × 106 M-1) was isolated from a random peptide library and fused with a bacterial antigen, ScaA of Orientia tsutsugamushi, the causative agent of scrub typhus. The ZNP/ZBP-ScaA complex was efficiently phagocytosed by a dendritic cell line, DC2.4, in vitro and significantly enhanced anti-ScaA antibody responses in vivo compared to control groups. In addition, immunization with the ZNP/ZBP-ScaA complex promoted the generation of IFN-γ-secreting T cells in an antigen-dependent manner. Finally, we observed that ZNP/ZBP-ScaA immunization provided protective immunity against lethal challenge of O. tsutsugamushi, indicating that ZNP can be used as a potent adjuvant when complexed with ZBP-conjugated antigen. CONCLUSIONS: ZNPs possess good adjuvant potential as a vaccine carrier when combined with an antigen having a high affinity to ZNP. When complexed with ZBP-ScaA antigen, ZNPs could induce strong antibody responses as well as protective immunity against lethal challenges of O. tsutsugamushi. Therefore, application of ZNPs combined with a specific soluble antigen could be a promising strategy as a novel vaccine carrier system.

Effects of Barium Chloride Exposure on Hormones and Genes of the Hypothalamic-Pituitary-Gonad Axis, and Reproduction of Zebrafish (Danio rerio).

Adult zebrafish pairs were exposed to sub-lethal concentrations of BaCl2 for 21 days, and the effects on reproduction, sex steroid hormones, and transcription of the genes belonging to the hypothalamic-pituitary-gonad (HPG) axis were investigated. The adverse effects on performances of F1 generation were further examined with or without subsequent exposure to BaCl2. Egg production was significantly decreased, and parental exposure to BaCl2 resulted in lesser rates of hatching. In males, exposure to BaCl2 resulted in greater concentrations of E2 along with greater mRNA expression of cyp19a. The results demonstrated that BaCl2 could modulate gene transcriptions and hormone production of the HPG axis in a sex-dependent way, which could cause adverse effects on reproduction and the development of offspring.

The effect of dialysis modality on annual mortality: A prospective cohort study.

Despite numerous studies on the effect of each dialysis modality on mortality, the issue remains controversial. We investigated the hazard rate of mortality in patients with incident end-stage renal disease (ESRD) concerning initial dialysis modality (hemodialysis vs. peritoneal dialysis). Using a nationwide, multicenter, prospective cohort in South Korea, we studied 2207 patients, of which 1647 (74.6%) underwent hemodialysis. We employed the weighted Fine and Gray model over the follow-up period using inverse probability of treatment and censoring weighting. Landmark analysis was used for identifying the changing effect of dialysis modality on individuals who remained event-free at each landmark point. No significant difference in hazard rate was observed overall. However, the peritoneal dialysis group had a significantly higher hazard rate than the hemodialysis group among patients under 65 years after 4- and 5- year follow-up. A similar pattern was observed among those with diabetes mellitus. Landmark analysis also showed the higher hazard rate for peritoneal dialysis at 2 years for the education-others group and at 3 years for the married group. These findings may inform dialysis modality decisions, suggesting a preference for hemodialysis in young patients with diabetes, especially for follow-ups longer than 3 years.

A comparative immunological assessment of multiple clinical-stage adjuvants for the R21 malaria vaccine in nonhuman primates.

Authorization of the Matrix-M (MM)-adjuvanted R21 vaccine by three countries and its subsequent endorsement by the World Health Organization for malaria prevention in children are a milestone in the fight against malaria. Yet, our understanding of the innate and adaptive immune responses elicited by this vaccine remains limited. Here, we compared three clinically relevant adjuvants [3M-052 + aluminum hydroxide (Alum) (3M), a TLR7/8 agonist formulated in Alum; GLA-LSQ, a TLR4 agonist formulated in liposomes with QS-21; and MM, the now-approved adjuvant for R21] for their capacity to induce durable immune responses to R21 in macaques. R21 adjuvanted with 3M on a 0, 8, and 23-week schedule elicited anti-circumsporozoite antibody responses comparable in magnitude to the R21/MM vaccine administered using a 0-4-8-week regimen and persisted up to 72 weeks with a half-life of 337 days. A booster dose at 72 weeks induced a recall response similar to the R21/MM vaccination. In contrast, R21/GLA-LSQ immunization induced a lower, short-lived response at the dose used. Consistent with the durable serum antibody responses, MM and 3M induced long-lived plasma cells in the bone marrow and other tissues, including the spleen. Furthermore, whereas 3M stimulated potent and persistent antiviral transcriptional and cytokine signatures after primary and booster immunizations, MM induced enhanced expression of interferon- and TH2-related signatures more highly after the booster vaccination. Collectively, these findings provide a resource on the immune responses of three clinically relevant adjuvants with R21 and highlight the promise of 3M as another adjuvant for malarial vaccines.

Active escape of Orientia tsutsugamushi from cellular autophagy.

Orientia tsutsugamushi, the causative agent of scrub typhus, is an obligate intracellular pathogen. After entry into host cells, the bacterium rapidly escapes from the endosomal pathway and replicates in the cytosol of eukaryotic host cells. Here we show that O. tsutsugamushi infection efficiently promotes cellular autophagy, a cell-autonomous defense mechanism of innate immunity. However, most of the internalized bacteria barely colocalized with the induced autophagosomes, even when stimulated with rapamycin, a chemical inducer of autophagy. Treatment of infected cells with tetracycline suppressed bacterial evasion from autophagy and facilitated O. tsutsugamushi targeting to autophagosomes, suggesting that the intracellular pathogen may be equipped with a bacterial factor or factors that block autophagic recognition. Finally, we also found that chemical modulators of cellular autophagy or genetic knockout of the atg3 gene does not significantly affect the intracellular growth of O. tsutsugamushi in vitro. These results suggest that O. tsutsugamushi has evolved to block autophagic microbicidal defense by evading autophagic recognition even though it activates the autophagy pathway during the early phase of infection.

Single-cell RNA-Seq reveals transcriptional regulatory networks directing the development of mouse maxillary prominence.

During vertebrate embryonic development, neural crest-derived ectomesenchyme within the maxillary prominences undergoes precisely coordinated proliferation and differentiation to give rise to diverse craniofacial structures, such as tooth and palate. However, the transcriptional regulatory networks underpinning such an intricate process have not been fully elucidated. Here, we perform single-cell RNA-Seq to comprehensively characterize the transcriptional dynamics during mouse maxillary development from embryonic day (E) 10.5-E14.5. Our single-cell transcriptome atlas of ∼28,000 cells uncovers mesenchymal cell populations representing distinct differentiating states and reveals their developmental trajectory, suggesting that the segregation of dental from the palatal mesenchyme occurs at E11.5. Moreover, we identify a series of key transcription factors (TFs) associated with mesenchymal fate transitions and deduce the gene regulatory networks directed by these TFs. Collectively, our study provides important resources and insights for achieving a systems-level understanding of craniofacial morphogenesis and abnormality.

An Alternative Splicing Variant of the Mixed-Lineage Leukemia 5 Protein Is a Cellular Adhesion Receptor for ScaA of Orientia tsutsugamushi.

Scrub typhus is a mite-borne disease caused by the obligately intracellular bacterium Orientia tsutsugamushi. We previously demonstrated that ScaA, an autotransporter membrane protein of O. tsutsugamushi, is commonly shared in various genotypes and involved in adherence to host cells. Here, we identified a mixed-lineage leukemia 5 (MLL5) mammalian trithorax group protein as a host receptor that interacts with ScaA. MLL5, identified by yeast two-hybrid screening, is an alternative splicing variant of MLL5 (vMLL5) which contains 13 exons with additional intron sequences encoding a tentative transmembrane domain. Indeed, vMLL5 is expressed on the plasma membrane as well as in intracellular compartments in eukaryotic cells and colocalized with adherent O. tsutsugamushi. In addition, ScaA-expressing Escherichia coli showed significantly increased adherence to vMLL5-overexpressing cells compared with vector control cells. We mapped the C-terminal region of the passenger domain of ScaA as a ligand for vMLL5 and determined that the Su(var)3-9, Enhancer of zeste, Trithorax (SET) domain of MLL5 is an essential and sufficient motif for ScaA binding. We observed significant and specific inhibition of bacterial adhesion to host cells in competitive inhibition assays using the C-terminal fragment of ScaA or the SET domain of vMLL5. Moreover, immunization with the C-terminal fragment of ScaA provided neutralizing activity and protective immunity against lethal challenge with O. tsutsugamushi as efficiently as vaccination with the whole passenger domain of ScaA. These results indicate that vMLL5 is a novel cellular receptor for ScaA-mediated adhesion of O. tsutsugamushi and facilitates bacterial adhesion to host cells, thereby enhancing bacterial infection. IMPORTANCE O. tsutsugamushi is a mite-borne pathogen that causes scrub typhus. As an obligately intracellular pathogen, its adhesion to and invasion of host cells are critical steps for bacterial growth. However, the molecular basis of the bacterial ligand and host receptor interaction is poorly defined. Here, we identified a splicing variant of MLL5 (vMLL5) as a cellular adhesion receptor of ScaA, an outer membrane autotransporter protein of O. tsutsugamushi. We mapped the interacting domains in the bacterial ligand and host receptor and confirmed their functional interaction. In addition, immunization with the C-terminal region of ScaA, which involves an interaction with the SET domain of vMLL5, not only induces enhanced neutralizing antibodies but also provides protective immunity against lethal challenge with O. tsutsugamushi.

Corrigendum: Differential association of viral dynamics with disease severity depending on patients' age group in COVID-19.

[This corrects the article DOI: 10.3389/fmicb.2021.712260.].

Corrigendum: Acute surge of atypical memory and plasma B-cell subsets driven by an extrafollicular response in severe COVID-19.

[This corrects the article DOI: 10.3389/fcimb.2022.909218.].

A single-cell atlas of in vitro multiculture systems uncovers the in vivo lineage trajectory and cell state in the human lung.

We present an in-depth single-cell atlas of in vitro multiculture systems on human primary airway epithelium derived from normal and diseased lungs of 27 individual donors. Our large-scale single-cell profiling identified new cell states and differentiation trajectories of rare airway epithelial cell types in human distal lungs. By integrating single-cell datasets of human lung tissues, we discovered immune-primed subsets enriched in lungs and organoids derived from patients with chronic respiratory disease. To demonstrate the full potential of our platform, we further illustrate transcriptomic responses to various respiratory virus infections in vitro airway models. Our work constitutes a single-cell roadmap for the cellular and molecular characteristics of human primary lung cells in vitro and their relevance to human tissues in vivo.

Corrigendum: Elevated IFNA1 and suppressed IL12p40 associated with persistent hyperinflammation in COVID-19 pneumonia.

[This corrects the article DOI: 10.3389/fimmu.2023.1101808.].

Elevated IFNA1 and suppressed IL12p40 associated with persistent hyperinflammation in COVID-19 pneumonia.

Introduction: Despite of massive endeavors to characterize inflammation in COVID-19 patients, the core network of inflammatory mediators responsible for severe pneumonia stillremain remains elusive. Methods: Here, we performed quantitative and kinetic analysis of 191 inflammatory factors in 955 plasma samples from 80 normal controls (sample n = 80) and 347 confirmed COVID-19 pneumonia patients (sample n = 875), including 8 deceased patients. Results: Differential expression analysis showed that 76% of plasmaproteins (145 factors) were upregulated in severe COVID-19 patients comparedwith moderate patients, confirming overt inflammatory responses in severe COVID-19 pneumonia patients. Global correlation analysis of the plasma factorsrevealed two core inflammatory modules, core I and II, comprising mainly myeloid cell and lymphoid cell compartments, respectively, with enhanced impact in a severity-dependent manner. We observed elevated IFNA1 and suppressed IL12p40, presenting a robust inverse correlation in severe patients, which was strongly associated with persistent hyperinflammation in 8.3% of moderate pneumonia patients and 59.4% of severe patients. Discussion: Aberrant persistence of pulmonary and systemic inflammation might be associated with long COVID-19 sequelae. Our comprehensive analysis of inflammatory mediators in plasmarevealed the complexity of pneumonic inflammation in COVID-19 patients anddefined critical modules responsible for severe pneumonic progression.

A Neural Crest-specific Overexpression Mouse Model Reveals the Transcriptional Regulatory Effects of Dlx2 During Maxillary Process Development.

Craniofacial morphogenesis is a complex process that requires precise regulation of cell proliferation, migration, and differentiation. Perturbations of this process cause a series of craniofacial deformities. Dlx2 is a critical transcription factor that regulates the development of the first branchial arch. However, the transcriptional regulatory functions of Dlx2 during craniofacial development have been poorly understood due to the lack of animal models in which the Dlx2 level can be precisely modulated. In this study, we constructed a Rosa26 site-directed Dlx2 gene knock-in mouse model Rosa26 CAG-LSL-Dlx2-3xFlag for conditionally overexpressing Dlx2. By breeding with wnt1 cre mice, we obtained wnt1 cre ; Rosa26 Dlx2/- mice, in which Dlx2 is overexpressed in neural crest lineage at approximately three times the endogenous level. The wnt1 cre ; Rosa26 Dlx2/- mice exhibited consistent phenotypes that include cleft palate across generations and individual animals. Using this model, we demonstrated that Dlx2 caused cleft palate by affecting maxillary growth and uplift in the early-stage development of maxillary prominences. By performing bulk RNA-sequencing, we demonstrated that Dlx2 overexpression induced significant changes in many genes associated with critical developmental pathways. In summary, our novel mouse model provides a reliable and consistent system for investigating Dlx2 functions during development and for elucidating the gene regulatory networks underlying craniofacial development.

Hdac4 Regulates the Proliferation of Neural Crest-Derived Osteoblasts During Murine Craniofacial Development.

Craniofacial development involves the regulation of a compendium of transcription factors, signaling molecules, and epigenetic regulators. Histone deacetylases (HDACs) are involved in the regulation of cell proliferation, differentiation, and homeostasis across a wide range of tissues, including the brain and the cardiovascular, muscular, and skeletal systems. However, the functional role of Hdac4 during craniofacial development remains unclear. In this study, we investigated the effects of knocking out Hdac4 on craniofacial skeletal development by conditionally disrupting the Hdac4 gene in cranial neural crest cells (CNCCs) using Cre-mediated recombination. Mice deficient for Hdac4 in CNCC-derived osteoblasts demonstrated a dramatic decrease in frontal bone formation. In vitro, pre-osteoblasts (MC3T3-E1 cells) lacking Hdac4 exhibited reduced proliferative activity in association with the dysregulation of cell cycle-related genes. These findings suggested that Hdac4 acts, at least in part, as a regulator of craniofacial skeletal development by positively regulating the proliferation of CNCC-derived osteoblasts.

Acute Surge of Atypical Memory and Plasma B-Cell Subsets Driven by an Extrafollicular Response in Severe COVID-19.

Background: Despite the use of vaccines and therapeutics against the coronavirus disease 2019 (COVID-19) pandemic, this severe disease has been a critical burden on public health, whereas the pathogenic mechanism remains elusive. Recently, accumulating evidence underscores the potential role of the aberrant B-cell response and humoral immunity in disease progression, especially in high-risk groups. Methods: Using single-cell RNA (scRNA) sequencing analysis, we investigated transcriptional features of B-cell population in peripheral blood from COVID-19 patients and compared them, according to clinical severity and disease course, against a public B-cell dataset. Results: We confirmed that acute B cells differentiate into plasma cells, particularly in severe patients, potentially through enhanced extrafollicular (EF) differentiation. In severe groups, the elevated plasma B-cell response displayed increased B-cell receptor (BCR) diversity, as well as higher levels of anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) spike antibodies in plasma, than those in moderate cases, suggesting more robust and heterogeneous plasma cell response in severe COVID-19 patients. Trajectory analysis identified a differentiation pathway for the EF B-cell response from active naïve to atypical memory B cells (AM2), in addition to the emergence of an aberrant plasma cell subset (PC2), which was associated with COVID-19 progression and severity. The AM2 and PC2 subsets surged in the acute phase of the severe disease and presented multiple inflammatory features, including higher cytokine expression and humoral effector function, respectively. These features differ from other B-cell subsets, suggesting a pathogenic potential for disease progression. Conclusion: The acute surge of AM2 and PC2 subsets with lower somatic hypermutation and higher inflammatory features may be driven by the EF B-cell response during the acute phase of severe COVID-19 and may represent one of the critical drivers in disease severity.