Mitochondrial-dependent oxidative phosphorylation is key for postnatal metabolic adaptation of alveolar macrophages in the lung.

Alveolar macrophages (AMs) seed in lung during embryogenesis and become mature in perinatal period. Establishment of acclimatization to environmental challenges is important, whereas the detailed mechanisms that drive metabolic adaptation of AMs remains to be elucidated. Here, we showed that energy metabolism of AMs was transformed from glycolysis prenatally to oxidative phosphorylation (OXPHOS) postnatally accompanied by up-regulated expression of mitochondrial transcription factor A (TFAM). TFAM deficiency disturbed mitochondrial stability and decreased OXPHOS, which finally impaired AM maintenance and function, but not AM embryonic development. Mechanistically, Tfam-deletion resulted in impaired mitochondrial respiration and decreased ATP production, which triggered endoplasmic reticulum (ER) stress to cause B cell lymphoma 2 ovarian killer (BOK) accumulation and abnormal distribution of intracellular Ca2+, eventually led to induce AM apoptotic death. Thus, our data illustrated mitochondrial-dependent OXPHOS played a key role in orchestrating AM postnatal metabolic adaptation.

IL-4-induced decrease in both the number and CTLA-4 expression of Treg impairs suppression of Th2 type inflammation in severe atopic dermatitis.

BACKGROUND: Treg plays a pivotal role in the suppression of Th2 cell and the maintenance of immune homeostasis. The precise molecular mechanism underlying the disruption of Treg suppression of Th2 cell and the promotion of Th2 type inflammation in allergic diseases remains elusive. OBJECTIVE: This study aims to investigate the molecular mechanism underlying quantitative and functional changes of Treg in AD. METHODS: The molecular mechanism was investigated using flow cytometry, mRNA sequencing, co-culture experiments, co-immunoprecipitation, chromatin immunoprecipitation, and bisulfite sequencing in vitro or in AD mice model and patients with AD. RESULTS: Increased proportion of Treg was detected in mild and moderate AD. Conversely, characteristic decrease in both the number and CTLA-4 expression of Treg was relevant to serum IL-4 level in severe AD patients, which was verified under a high concentration of IL-4 treatment in vitro. The underlying mechanism is that IL-4/pSTAT6 pathway recruits DNMT1 and HDAC2 to inhibit transcriptional regulation of Foxp3 and CTLA-4 loci. High level of IL-4 impaired the suppression of Treg against Th2 cell differentiation mediated by CTLA-4, and blockade of IL-4Rα signaling in Treg restored Treg number and suppression of Th2 cell in AD model mice and patients with AD. CONCLUSION: The number of Treg is relevant to stratification of severity and serum IL-4 level in patients with AD. Abnormal high level of IL-4 epigenetically triggers a decrease in both the number and CTLA-4 expression of Treg. The reduced expression of CTLA-4 on Treg induced by IL-4 impairs suppression of Th2 cell differentiation.

Dynamic pathological analysis reveals a protective role against skin fibrosis for TREM2-dependent macrophages.

Rationale: Systemic sclerosis (SSc) is a chronic and incurable autoimmune disease with high mortality rates, and skin fibrosis is one of distinguishing hallmarks in the pathogenesis. However, macrophage heterogeneity regulating skin fibrosis remain largely unknown. Methods: We established mouse disease model and performed single-cell RNA-sequencing (scRNA-seq) to resolve the dynamic and heterogenous characteristics of macrophages in skin fibrosis, and the role of TREM2-dependent macrophages in the pathological process was investigated using knockout mice and intraperitoneal transferring TREM2+ macrophages combining with functional assays. Results: We show that TREM2-expressing macrophages (TREM2+ MФs) accumulate in injured skin of mice treated by bleomycin (BLM) and human SSc, and their gene signatures and functional pathways are identified in the course of disease. Genetic ablation of Trem2 in mice globally accelerates and aggravates skin fibrosis, whereas transferring TREM2hi macrophages improves and alleviates skin fibrosis. Amazingly, we found that disease-associated TREM2+ MФs in skin fibrosis exhibit overlapping signatures with fetal skin counterparts in mice and human to maintain skin homeostasis, but each has merits in skin remodeling and development respectively. Conclusion: This study identifies that TREM2 acts as a functional molecule and a major signaling by which macrophage subpopulations play a protective role against fibrosis, and disease-associated TREM2+ MФs in skin fibrosis might undergo a fetal-like reprogramming similar to fetal skin counterparts.

Apolipoprotein E deficiency attenuated osteogenesis via down-regulating osterix.

Apolipoprotein E (ApoE), a ligand for low-density lipoprotein receptors, is strongly induced during osteogenesis and has a physiologic role in regulating osteoblast function, but the mechanisms of its action are still unclear. The study aims to elucidate the influence and molecular mechanisms of ApoE on bone formation. An ovariectomy-induced osteoporotic model were conducted in ApoE knockout (ApoE-/-) mice to study the effect of ApoE on the bone system. Bone quality were assessed through bone mineral density and histomorphometric analysis. To investigate the underlying role and mechanisms of ApoE during osteogenesis, primary osteoblasts from the calvariums of newborn ApoE-/- or wild-type (WT) mice were cultured in the osteoblastic differentiation medium in vitro for further research. Our animal experiment data showed that ApoE-/- mice exhibited bone loss, exacerbated by estrogen deprivation after ovariectomy. ApoE deficiency attenuated osteoblast activity and inhibited osteoblast osteogenesis, accompanied by decreased osterix expression. ApoE deficiency did not affect primary osteoblast viability and collagen-1 expression. Moreover, osteoprotegerin expression in ApoE-/- osteoblasts was reduced compared to WT controls. Our study demonstrated that ApoE gene deficiency contributed to bone loss and attenuated osteogenesis by down-regulating osterix expression.

Women undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) might benefit from maintaining serum luteinizing hormone levels: A retrospective analysis.

We aimed to evaluate the effect of serum luteinizing hormone (LH) levels on human chorionic gonadotropin (HCG) injection day (LHHCG) on outcomes of in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) patients. It is a retrospective cohort study involving 620 women who had an IVF cycle in Taizhou Hospital Affiliated to Wenzhou Medical University between 2018-2020. The participants were divided into different groups according to LHHCG level and age. The clinical data and outcomes were compared between groups. The numbers of follicles (≥ 14 mm) on HCG day, retrieved oocytes, mature oocytes, and two pronuclei (2PN) embryos in women with LHHCG < 2 IU/L were more than those with LHHCG ≥ 2 IU/L. Women with LHHCG < 2 IU/L had lower high-quality embryo rate (42.2% vs. 46.5%, p = 0.002) and implantation rate (40.0% vs. 58.8%, p = 0.044) compared to those with LHHCG ≥ 2 IU/L. When LHHCG < 2 IU/L, there was no significant difference in implantation rates in patients < 35 years compared to those ≥ 35 years. When LHHCG ≥ 2 IU/L, patients < 35 years old had higher implantation rates (71.7% vs. 41.2%, p < 0.001) compared to those ≥ 35 years old. The success rates of IVF fertilization and ICSI fertilization and biochemical and clinical pregnancy rates were not significantly different between groups. Our results demonstrated that women undergoing IVF/ICSI-ET might benefit from maintaining LHHCG levels at ≥ 2 IU/L. In addition, age might associate with LHHCG levels and be a better determining factor of the transfer outcome than serum LHHCG levels for IVF/ICSI-ET.

Sodium thiosulfate inhibits epithelial-mesenchymal transition in melanoma via regulating the Wnt/ß-catenin signaling pathway.

BACKGROUND: Melanoma is the most common form of skin cancer. Given its high metastasis and high recurrence, its therapies are constantly updated. OBJECTIVE: The study aims to prove the efficacy of sodium thiosulfate (STS), an antidote to cyanide or nitroprusside poisoning, in melanoma treatment. METHODS: We tested the effect of STS by culturing melanoma cells (B16 and A375) in vitro and establishing melanoma mouse models in vivo. The proliferation and viability of melanoma cells were measured by the CCK-8 test, cell cycle assay, apoptosis analysis, wound healing assay, and transwell migration assay. The expression of apoptosis-related molecules, epithelial-mesenchymal transition (EMT)-associated molecules, and the Wnt/ß-catenin signaling pathway-related molecules were determined by Western blotting and immunofluorescence. RESULTS: The high metastasis of melanoma is considered to be linked to the EMT process. The scratch assay using B16 and A375 cells also showed that STS could inhibit the EMT process of melanoma. We demonstrated that STS inhibited the proliferation, viability, and EMT process of melanoma by releasing H2S. STS-mediated weakening of cell migration was related to the inhibition of the Wnt/ß-catenin signaling pathway. Mechanistically, we defined that STS inhibited the EMT process via the Wnt/ß-catenin signaling pathway. CONCLUSIONS: These results suggest that the negative effect of STS on melanoma development is mediated by the reduction of EMT via the regulation of the Wnt/ß-catenin signaling pathway, which provides a new clue to treating melanoma.

Loss-of-function mutations in CST6 cause dry skin, desquamation and abnormal keratosis without hypotrichosis.

Cystatin M/E (encoded by the CST6 gene) is a cysteine protease inhibitor, that exerts regulatory and protective effects against uncontrolled proteolysis mainly by directly regulating cathepsin V, cathepsin L, and legumain activities. Previous studies have suggested that CST6 may exert a regulatory role in epidermal differentiation and hair follicle formation by inhibiting the activity of respective cognate target proteases. However, until recently, studies have revealed that loss- or gain-of-function of the CST6 gene causes dry skin with hypotrichosis in humans. Here, we reported two siblings of Chinese origin with dry skin, desquamation and abnormal keratosis without hypotrichosis. By applying whole-exome sequencing, we identified homozygous loss-of-function mutation c.251G > A (p.Gly84Asp) in the CST6 gene as the underlying genetic cause. Further fluorimetric enzyme assays demonstrated the mutant cystatin M/E protein lost its inhibitory function on the protease activity of cathepsins. Moreover, the corresponding mutation in mice resulted in excessive cornification, desquamation, impaired skin barrier function, and abnormal proliferation and differentiation of keratinocytes. In conclusion, the homozygous missense mutation c.251G > A in CST6 gene resulted in dry skin, desquamation, as well as abnormal keratosis of the skin, promoting our understanding of the role of protease-antiprotease balance in human skin disorders.

Inhibitory Effect of Nano-targeted Micelle Administration Combined with in Vitro Radiotherapy on Glioma Based on Nuclear Magnetic Resonance Technology.

Glioma is a malignant tumor originating from the central nervous system. Glioma is the incidence rate of the central nervous system in adults. Nanotechnology has been widely used in drug delivery in vivo, achieving targeted drug delivery through surface modification. At the same time, the samples measured by NMR have no bias to all compounds, and there is no need for specific internal standards for quantification. Therefore, based on the use of nuclear magnetic resonance technology, this paper analyzed the inhibitory effect of nano-targeted micelles combined with in vitro radiotherapy on glioma. The results show that the coupling constants of ß - CH3 of Ala and ß - CH3 of Lac are close. It is difficult to distinguish the spectral lines of Ala and Lae by 1.5T NMR. DHA-PLys(s-s)P can efficiently deliver drugs across BBB and into brain parenchymal cells to release drugs. Due to its increased stability in the systemic circulation, DHA-PLys(s-s)P can help to improve drug delivery efficiency. The DNA damage of U87 and U251 cells was more serious than that of C6 cells. There was a positive correlation between DNA damage and Cho/Cr ratio, indicating that nano-targeted micelles combined with in vitro radiotherapy have an inhibitory effect on glioma.

Knockdown of NDUFC1 inhibits cell proliferation, migration, and invasion of hepatocellular carcinoma.

Background: NADH: ubiquinone oxidoreductase subunit C1(NDUFC1) encodes a subunit of the Complex I, which may support the structural stability of Complex I and assist in its biogenesis. The expression and functional roles of NDUFC1 in hepatocellular carcinoma (HCC) remain unknown. Result: We knocked down the expression of NDUFC1 in HCC cell lines to explore the effects of NDUFC1 downregulation on HCC in vitro. MTT assay determined that downregulation of NDUFC1 significantly inhibited cell proliferation. Flow cytometry with (propidium iodide) PI staining indicated silencing of NDUFC1 arrested cell cycle of BEL-7404 cells at G2 phase and SK-HEP-1 cells at S/G2 phase. Annexin V-PI double staining and flow cytometric analysis showed that the downregulation of NDUFC1 significantly increased the population of apoptotic cells. Wound-healing assay and transwell assay indicated that the downregulation of NDUFC1 suppressed the migration and invasion of HCC cells. According to the detection of complex1 activity, we found that the activity of NDUFC1 silenced group decreased, whereas the content of ROS increased. Furthermore, combined with bioinformatics analysis of senescence-related genes, we found that the silence of NDUFC1 in HCC could induce senescence and inhibit autophagy. In addition, NDUFC1 could correlate positively with cancer-related pathways, among which the p53 pathways and the PI3K/Akt/mTOR pathways. Finally, NDUFC1 is high expression in HCC specimens. High NDUFC1 expression was associated with poor prognosis and was an independent risk factor for reduced overall survival (OS). Conclusions: Our study indicated, for the first time, that NDUFC1 is an independent risk factor for the poor prognosis of HCC patients. NDUFC1 may promote tumor progression by inhibiting mitochondrial Complex I and up-regulating ROS through multiple cancer-related and senescence-related pathways of HCC, including p53 pathways and PI3K/Akt/mTOR pathways. We suppose that NDUFC1 might be a potential target for the mitochondrial metabolism therapy of HCC.

FibROAD: a manually curated resource for multi-omics level evidence integration of fibrosis research.

Organ fibrosis represents a vital health threat that substantially contributes to yearly mortality rates. While a considerable amount of research has been conducted on fibrosis, these reports have only focused on specific organs as affected within distinct disorders. Accordingly, results from such studies have been unable to provide a comprehensive understanding of the pathological processes involved. Here, we describe the development of FibROAD, an open-access database that integrates evidence from fibrosis-associated disorders as obtained from both the literature and multi-omics data. This resource will greatly assist both researchers and clinicians in the comprehension and treatment of this condition. FibROAD currently involves an assembly of 232 strong evidence-based fibrosis-related genes (FRGs) as garnered from 909 PubMed publications and contains lists of multi-omics data from > 4000 samples including RNA-seq, single-cell RNA-seq, miRNA-seq, ChIP-seq, ATAC-seq MeDIP-seq and MBD-seq as obtained from 17 different organs in 5 species. Results from integrative analyses as obtained using FibROAD have demonstrated that FRGs can be indicators for a wide range of organ fibrosis and reveal potential pro-fibrotic candidate genes for fibrosis research. In conclusion, FibROAD serves as a convenient platform where researchers can acquire integrated evidence and a more comprehensive understanding of fibrosis-related disorders. Database URL  https://www.fibroad.org.

Effect of Different Sterilization Methods on the Microbial and Physicochemical Changes in Prunus mume Juice during Storage.

This study evaluated the pasteurization (P), ozone (O3), ultrasonic (US), and high-hydrostatic-pressure (HHP) sterilization approaches for processing of Prunus mume regarding browning factors and microorganisms, compared with non-sterilization (control check, CK) treatment. The microorganisms (total bacterial count and fungi and yeast count) in the juice were identified after different sterilization techniques, while the quality parameter changes (degree of browning, color measurements, total phenolic content, reducing sugar, ascorbic acid, 5-hydroxymethyl furaldehyde (5-HMF), amino acid nitrogen, total soluble solids (TSS), pH value) were investigated. The results indicate that P and HHP treatment reduced non-enzymatic browning while substantially impacting the color measurements, TSS, and pH, while the sterilization effect was remarkable, with a rate exceeding 90%. Furthermore, the Prunus mume juices treated with P and HHP sterilization were used as the objects, and the CK group was used as the control group. They were placed at 4 °C, 25 °C and 37 °C, respectively, and stored in dark for 15 d. Sampling and determination were carried out on 0, 3, 6, 9, 12, and 15 d, respectively. M-&-Y (molds and yeasts) were not detected in the late storage period, and no obvious microbial growth was observed during storage, indicating that P and HHP treatments could ensure the microbial safety of Prunus mume juice. P- and HHP- treated Prunus mume juice has better quality and low temperature storage is beneficial for maintaining the quality of Prunus mume juice. Therefore, P treatment or HHP treatment combined with low temperature storage could achieve a more ideal storage effect. Overall, this study conclusively established that P and HHP methods were suitable for sterilizing Prunus mume juice. These techniques minimally affected overall product quality while better maintaining the quality parameters than the untreated juice samples and those exposed to O3 and US treatment.

circRNA_0000285 knockdown suppresses viability and promotes apoptosis of cervical cancer cells by sponging microRNA-654-3p.

Cervical cancer (CC) is one of the most common gynecological tumors worldwide. Several studies have reported that circular RNAs (circRNAs) play important roles in various types of diseases, including cancer. Thus, the present study aimed to investigate the role of circRNA_0000285 in CC development. Dual-luciferase reporter and RNA pull-down assays were performed to verify the binding region between circRNA_0000285 and miR-654-3p. The expression levels of circRNA_0000285 and miR-654-3p were analyzed in CC and the corresponding normal tissues, as well as in SiHa, HeLa, and NC104 cells using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, the effect of circRNA_0000285 inhibition on cell viability, apoptosis, and the expression of apoptosis-related markers was assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), flow cytometry, and Western blotting assays, respectively. The results verified that miR-654-3p directly targeted circRNA_0000285 expression. circRNA_0000285 was overexpressed and miR-654-3p expression was downregulated in CC tissues and cells compared to that in control. Moreover, circRNA_0000285 knockdown suppressed the viability and promoted the apoptosis of CC cells, which was accompanied by the downregulated and upregulated expressions B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X (Bax), respectively. The ratio of Bax/Bcl-2 levels also increased following circRNA_0000285 knockdown. However, these findings were abrogated after miR-654-3p inhibitor treatment. Hence, circRNA_0000285 knockdown suppressed cell viability and promoted apoptosis by targeting miR-654-3p in CC.

Oncostatin M sensitizes keratinocytes to UVB-induced inflammation via GSDME-mediated pyroptosis.

BACKGROUND: Oncostatin M (OSM), an interleukin-6 (IL-6) family proinflammatory cytokine, plays a critical role in inflammatory skin diseases, but its mechanism of action is not well understood. OBJECTIVE: To demonstrate the mechanism of OSM induced pyropotosis in normal human epidermal keratinocytes (NHEKs) and immortalized human keratinocytes (HaCaT cells). METHODS: NHEKs and HaCaT cells were treated with OSM. Knockout of OSM receptor (OSMR) with CRISPR/Cas9 system, knockdown of GSDME with small interfering RNA and primary keratinocytes from Osmr-/- and Gsdme-/- mice were used to study the effect of OSMR and GSDME. After treatment of OSM, NHEKs and HaCaT cells were irradiated with UVB. The mRNA was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and RNA sequencing, protein level was detected by Western Blotting, Elisa and immunofluorescence. Cell death was examined by lactate dehydrogenase (LDH) releasing. RESULTS: Here we found that OSM induced pyropotosis in NHEKs and HaCaT cells, but knockout of OSMR abolished pyropotosis. RNA sequencing revealed an upregulation of several key genes involved in NLRP3 inflammasome activation following OSM treatment, among which NLRP3, GSDME, and IL-1ß were confirmed by qRT-PCR and Western Blotting. Knockdown of GSDME alleviated OSM-induced pyropotosis. Pretreatment of OSM boosted UVB-induced pyroptosis and inflammation in NHEKs and HaCaT cells, and this priming function was lost in keratinocytes of Osmr-/- and Gsdme-/- mice. Similar results were obtained in a 3-dimensional culture of human epidermis. CONCLUSION: OSM functions as a priming cytokine to enhance UVB-induced inflammation in keratinocytes, providing insight into the pathogenesis of inflammatory skin diseases.

Single-cell transcriptome analysis reveals the dynamics of human immune cells during early fetal skin development.

The immune system of skin develops in stages in mice. However, the developmental dynamics of immune cells in human skin remains elusive. Here, we perform transcriptome profiling of CD45+ hematopoietic cells in human fetal skin at an estimated gestational age of 10-17 weeks by single-cell RNA sequencing. A total of 13 immune cell types are identified. Skin macrophages show dynamic heterogeneity over the course of skin development. A major shift in lymphoid cell developmental states occurs from the first to the second trimester that implies an in situ differentiation process. Gene expression analysis reveals a typical developmental program in immune cells in accordance with their functional maturation, possibly involving metabolic reprogramming. Finally, we identify transcription factors (TFs) that potentially regulate cellular transitions by comparing TFs and TF target gene networks. These findings provide detailed insight into how the immune system of the human skin is established during development.

C-C chemokine receptor type 6 modulates the biological function of osteoblastogenesis by altering the expression levels of Osterix and OPG/RANKL.

Circulating inflammatory factors affect osteoblast and osteoclast formation and activity in osteoporosis. Estrogen affects the migration of Th17 cells via the C-C chemokine receptor type 6 (CCR6) and C-C chemokine ligand 20 (CCL20) signaling pathways to modulate bone metabolism; however, it is unclear whether and how CCR6 modulates bone homeostasis. In the present study, CCR6 knockout (CCR6-/-) mice were selected to investigate the effects of CCR6 in the regulation of homeostasis of osteoblasts and osteoclasts. Primary osteoblasts were isolated from the calvarium of newborn CCR6-/- or wild-type mice, followed by osteoblastic differentiation culture in vitro. CCR6 deletion reduced osteoblast activity in terms of alkaline phosphatase (ALP) activity and inhibited osteoblast mineralization according to the results of Alizarin Red S staining, whereas it did not affect the proliferation of osteoblasts. CCR6 deletion inhibited Osterix mRNA expression in osteoblasts during the late stage of mineralization in vitro, while it did not affect mRNA expression levels of runt-related transcription factor 2 (Runx2) and Collagen-1. The ratio of osteoprotegerin (OPG) /receptor activator of nuclear factor κ-Β ligand (RANKL) mRNA level in osteoblasts was decreased by CCR6 deficiency in the culture treated with 1,25(OH)2D3/PGE2, while there was no effect observed in the normal culture environment. The results provide novel insights, such as that CCR6 deletion suppresses osteoblast differentiation by downregulating the expression levels of the transcription factor Osterix, and indirectly promotes osteoclast production by increasing transcription of RANKL. This may be one of the mechanisms via which CCR6 deletion regulates bone metabolism.

Single-cell RNA-seq reveals fibroblast heterogeneity and increased mesenchymal fibroblasts in human fibrotic skin diseases.

Fibrotic skin disease represents a major global healthcare burden, characterized by fibroblast hyperproliferation and excessive accumulation of extracellular matrix. Fibroblasts are found to be heterogeneous in multiple fibrotic diseases, but fibroblast heterogeneity in fibrotic skin diseases is not well characterized. In this study, we explore fibroblast heterogeneity in keloid, a paradigm of fibrotic skin diseases, by using single-cell RNA-seq. Our results indicate that keloid fibroblasts can be divided into 4 subpopulations: secretory-papillary, secretory-reticular, mesenchymal and pro-inflammatory. Interestingly, the percentage of mesenchymal fibroblast subpopulation is significantly increased in keloid compared to normal scar. Functional studies indicate that mesenchymal fibroblasts are crucial for collagen overexpression in keloid. Increased mesenchymal fibroblast subpopulation is also found in another fibrotic skin disease, scleroderma, suggesting this is a broad mechanism for skin fibrosis. These findings will help us better understand skin fibrotic pathogenesis, and provide potential targets for fibrotic disease therapies.

Epidermal resident γδ T cell development and function in skin.

Epidermal resident γδ T cells, or dendritic epidermal T cells (DETCs) in mice, are a unique and conserved population of γδ T cells enriched in the epidermis, where they serve as the regulators of immune responses and sense skin injury. Despite the great advances in the understanding of the development, homeostasis, and function of DETCs in the past decades, the origin and the underlying molecular mechanisms remain elusive. Here, we reviewed the recent research progress on DETCs, including their origin and homeostasis in the skin, especially at transcriptional and epigenetic levels, and discuss the involvement of DETCs in skin diseases.

Smad2/4 Signaling Pathway Is Critical for Epidermal Langerhans Cell Repopulation Under Inflammatory Condition but Not Required for Their Homeostasis at Steady State.

Epidermal Langerhans cells (LCs) are skin-resident dendritic cells that are essential for the induction of skin immunity and tolerance. Transforming growth factor-ß 1 (TGFß1) is a crucial factor for LC maintenance and function. However, the underlying TGFß1 signaling pathways remain unclear. Our previous research has shown that the TGFß1/Smad3 signaling pathway does not impact LC homeostasis and maturation. In this study, we generated mice with conditional deletions of either individual Smad2, Smad4, or both Smad2 and Smad4 in the LC lineage or myeloid lineage, to further explore the impact of TGFß1/Smad signaling pathways on LCs. We found that interruption of Smad2 or Smad4 individually or simultaneously in the LC lineage did not significantly impact the maintenance, maturation, antigen uptake, and migration of LCs in vivo or in vitro during steady state. However, the interruption of both Smad2 and Smad4 pathways in the myeloid lineage led to a dramatic inhibition of bone marrow-derived LCs in the inflammatory state. Overall, our data suggest that canonical TGFß1/Smad2/4 signaling pathways are dispensable for epidermal LC homeostasis and maturation at steady state, but are critical for the long-term LC repopulation directly originating from the bone marrow in the inflammatory state.

Evaluation of Maternal Serum sHLA-G Levels for Trisomy 18 Fetuses Screening at Second Trimester.

Human leukocyte antigen-G (HLA-G) has been widely acknowledged to play critical roles in fetal-maternal maintenance. However, the significance of using maternal serum sHLA-G to detect prenatal chromosomal abnormality has not been investigated. In China, prenatal screening using maternal α-fetoprotein (AFP), unconjugated estriol (uE3), and free ß subunit human chorionic gonadotropin (ß-hCG) in the second trimester has been widely applied. In this study, we evaluated the use of sHLA-G as a screening marker, compared with traditional second trimester prenatal screening. Serum samples from 1,019 singleton women in their second trimester were assessed. Among them, 139 infants were confirmed with trisomy 21 (T21) by karyotyping, 83 were confirmed with trisomy 18 (T18), and the remaining 797 infants had no abnormalities. The sHLA-G levels in maternal sera were significantly lower in pregnant women with T18 fetuses (median: 47.8 U/ml, range: 9.8-234.2 U/ml) and significantly higher in those with T21 fetuses (median: 125.7 U/ml, range: 28.7-831.7 U/ml), compared with the normal controls (median: 106.3 U/ml, range: 50.5-1136.4 U/ml) (p < 0.001). The risk values of the screening of T21 or T18 fetuses were assessed using mean and standard deviation log10 analyte multiples of median (MoM) which showed that the predictive values of sHLA-G were the same as free ß-hCG, and superior to AFP and uE3 for T18 screening. Logistic regression analysis revealed that sHLA-G MoM was the highest risk factor associated with pregnant women carrying T18 fetuses [Exp(B): 171.26, 95% CI: 36.30-807.97, p < 0.001]. Receiver operating characteristic (ROC) analysis revealed that the area under ROC curve for sHLA-G MoM was 0.915 (95% CI, 0.871-0.959, p < 0.001), for AFP MoM was 0.796 (95% CI, 0.730-0.861, p < 0.001), for free ß-hCG MoM was 0.881 (95% CI, 0.829-0.934, p < 0.001), and for uE3 MoM was 0.876 (95% CI, 0.828-0.923, p < 0.001) in the T18 group. sHLA-G MoM demonstrated the best sensitivity and negative predictive value. For the first time, our findings reveal that sHLA-G is a better second trimester screening marker for the detection of T18 fetuses and the combined application of sHLA-G with AFP, free ß-hCG, and uE3 could improve clinical screening for T18 fetuses.