Cell Types Research Articles

Acoustically targeted measurement of transgene expression in the brain.

Gene expression is a critical component of brain physiology, but monitoring this expression in the living brain represents a major challenge. Here, we introduce a new paradigm called recovery of markers through insonation (REMIS) for noninvasive measurement of gene expression in the brain with cell type, spatial, and temporal specificity. Our approach relies on engineered protein markers that are produced in neurons but exit into the brain's interstitium. When ultrasound is applied to targeted brain regions, it opens the blood-brain barrier and releases these markers into the bloodstream. Once in blood, the markers can be readily detected using biochemical techniques. REMIS can noninvasively confirm gene delivery and measure endogenous signaling in specific brain sites through a simple insonation and a subsequent blood test. REMIS is reliable and demonstrated consistent improvement in recovery of markers from the brain into the blood. Overall, this work establishes a noninvasive, spatially specific method of monitoring gene delivery and endogenous signaling in the brain.

The spatial structure of the tumor immune microenvironment can explain and predict patient response in high-grade serous carcinoma.

Ovarian cancer is the deadliest gynecological malignancy, and therapeutic options and mortality rates over the last three decades have largely not changed. Recent studies indicate that the composition of the tumor immune microenvironment (TIME) influences patient outcomes. To improve spatial understanding of the TIME, we performed multiplexed ion beam imaging on 83 human high-grade serous carcinoma tumor samples, identifying about 160,000 cells across 23 cell types. For 77 of these samples meeting inclusion criteria, we generated composition features based on cell type proportions, spatial features based on the distances between cell types, and spatial network features representing cell interactions and cell clustering patterns, which we linked to traditional clinical and immunohistochemical variables and patient overall survival (OS) and progression-free survival (PFS) outcomes. Among these features, we found several significant univariate correlations, including B-cell contact with M1 macrophages (OS hazard ratio HR=0.696, p=0.011, PFS HR=0.734, p=0.039). We then used high-dimensional random forest models to evaluate out-of-sample predictive performance for OS and PFS outcomes and to derive relative feature importance scores for each feature. The top model for predicting low or high PFS used TIME composition and spatial features and achieved an average AUC (area under the receiver-operating characteristic curve) score of 0.71. The results demonstrate the importance of spatial structure in understanding how the TIME contributes to treatment outcomes. Furthermore, the present study provides a generalizable roadmap for spatial analyses of the TIME in ovarian cancer research.

Distinct granzyme k expression in immune cells: a single-cell rna-seq meta-analysis.

Granzymes are essential serine proteases in cytotoxic T cells and natural killer (NK) cells, with GZMK's expression being less understood. This study aims to uncover GZMK expression profiles across various immune cell types using single-cell RNA sequencing meta-analysis. This study aims to uncover GZMK expression profiles across various immune cell types using single-cell RNA sequencing meta-analysis. We conducted a meta-analysis using cellxgene, an interactive data exploration platform developed by the Chan Zuckerberg Initiative. We focused on mature T cells, NK cells, B cells, and NKT cells. We also checked transcription factor binding sites at the granzyme gene promoter regions using JASPAR. Comparative analysis was also done using mouse single-cell RNA sequencing data. GZMK was the most lowly expressed in NK cells and mature NKT cells in most tissues except for colon and lymph nodes. In mature T cells, GZMK is similarly or more highly expressed than other granzymes. HBCA data revealed weak expression of GZMK in NK cells but strong expression in effector memory CD8-positive, alpha-beta T cells. Combined data shows no significant difference in GZMK expression between cell types. Subtype analysis shows that GZMK expression was higher in CD16-negative, CD56-bright NK cells when compared to CD16-positive, CD56-dim NK cells. We also identified unique transcription factor binding sites for GZMK. While this pattern in mouse data with low Gzmk expression in NK cells and higher T cells was repeated. GZMK expression is distinctively regulated among immune cells and tissues, with unique promoter regions and transcription factor binding sites contributing to this differential expression. These insights into GZMK's role in immune function and regulation offer potential therapeutic targets.

Bovine respiratory syncytial virus enhances the attachment of Trueperella pyogenes to cells.

In cattle, bovine respiratory syncytial virus (BRSV) is associated with secondary bacterial infections; however, the mechanisms of the interaction between BRSV and bacteria are unclear. Trueperella pyogenes (T. pyogenes) causes pneumonia in cattle and is involved in secondary infections following viral infections. In this study, we evaluated the effect of BRSV infection on the adhesion of T. pyogenes to BRSV-infected cells. BRSV infection significantly enhanced the adhesion of T. pyogenes to cells in a multiplicity of infection- and time-dependent manner. The BRSV-mediated change in the adhesion of T. pyogenes was widely observed in various cell types and bacterial strains. The results from the gentamicin protection assay showed that BRSV infection did not affect the intracellular invasion ability of T. pyogenes. Furthermore, adhesion assays conducted using BRSV G protein-expressing cells and anti-BRSV G antibodies revealed that the increased adhesion of T. pyogenes to cells was mediated by the G protein of BRSV. In addition, immunofluorescence assay revealed the colocalization of BRSV G protein and T. pyogenes. Thus, BRSV infection can potentially lead to bovine respiratory disease complex by promoting the adhesion of T. pyogenes to the infected cells.

Prognostic value of 18F-FDG PET/CT in postoperative recurrence of retroperitoneal liposarcoma: a single-center retrospective study.

Recurrence is the leading cause of tumor-related death in retroperitoneal liposarcoma (RPLPS). Variant subtypes of RPLPS determine different recurrence 18F]-fluoro-2-deoxy-D-glucose (18F-FDG) PET/computed tomography (PET/CT). This study analyzed the characteristics of different histologic subtypes of 18F-FDG PET/CT and their associations with recurrence and prognosis. Clinical-pathological information, 18F-FDG PET/CT data, recurrence, and progression-free survivals (PFS) of 83 patients with RPLPS were collected. Maximum and peak standardized uptake values (SUVmax and SUVpeak, respectively) and mean CT value (CTmean) of tumors were measured and correlated with histologic subtype. The predictability of SUVmax, SUVpeak, and CTmean for the histologic subtype was evaluated using receiver operating characteristics (ROC) max and SUVpeak for recurrence. Kaplan-Meier analysis was performed to max and SUVpeak were risk factors for recurrence. Studied patients with different types of liposarcomas. Dedifferentiated liposarcomas (DDLPS) had higher SUVmax and SUVpeak than well-differentiated (WDLPS) and myxoid/round cell (MLPS) types. WDLPS had lower CTmean values compared to MLPS and DDLPS. Using ROC curves, determined cut-off values for SUVmax (5.1) to differentiate DDLPS, SUVpeak (3.0) for WDLPS, and CTmean (12.3 Hu) for WDLPS. These cut-offs were found to be best for predicting recurrence. Kaplan-Meier analysis showed that histologic subtype, SUVmax, and SUVpeak were all linked to recurrence-free survival. The use of SUV and CT features on 18F-FDG PET/CT imaging may increase confidence in subtype diagnosis. Patients with SUVmax > 5.1 or SUVpeak > 3.0 suggest a poor prognosis.

Pathological examination of factors involved in PD-L1 expression in patients with oral tongue squamous cell carcinoma.

Tumor tissues comprise cancer cells and stromal cells, and their interactions form the cancer microenvironment. Therefore, treatments targeting cells other than cancer cells are also actively being developed, and among them, treatment targeting PD-1, an immune checkpoint molecule that is important in tumor immune evasion, has also been indicated for head and neck cancer. PD-L1, a ligand of PD-1, is expressed in both tumor cells and stromal cells, and the scoring system based on the combined positivity rates of both types of cells, the combined positive score (CPS), is used for predicting treatment effect. However, much is unknown regarding the expression of PD-L1. In this study, we histopathologically examined factors controlling the expression of PD-1/PD-L1. This study included 37 patients who underwent resection surgery for tongue squamous cell carcinoma in the Department of Oral and Maxillofacial Surgery at Tokyo Dental College Suidobashi Hospital. The expression levels of PD-L1, α-SMA, and p53 were assessed by immunohistochemical staining. Seven participants had CPS ≥ 20, twenty-four participants had 1 ≤ CPS < 20, and six participants had CPS < 1. The overall positivity rate of α-SMA, a marker for cancer-associated fibroblasts (CAFs), was 27% (10/37 participants), and the positivity rates of α-SMA for the three CPS groups were 85.7% (6/7 participants), 16.7% (4/24 participants), and 0% (0/6 participants), respectively. In addition, the overall positivity rate of p53 was 37.8% (14/37 participants), and the positivity rates of p53 for the three CPS groups were 71.4% (5/7 participants), 37.5% (9/24 participants), and 0% (0/6 participants), respectively. The expression of PD-L1 demonstrated an association with α-SMA and p53 positivity. In addition, compared with the expression of p53, the expression of α-SMA demonstrated a higher association with PD-L1 expression in patients with a high CPS. The abovementioned findings suggest that the interactions between CAFs, cancer cells, and immunocompetent cells may regulate the expression of PD-L1.

In-depth histological, lectin-histochemical, immunohistochemical and ultrastructural description of the olfactory rosettes and olfactory bulbs of turbot (Scophthalmus maximus).

Chemical communication through olfaction is crucial for fish behaviours, mediating in socio-sexual behaviours as reproduction. Turbot, a flatfish with significant aquaculture production, possesses a well-developed olfactory system from early developmental stages. After metamorphosis, flatfish acquire their characteristic bilateral asymmetry with an ocular side facing the open water column, housing the dorsal olfactory rosette, and a blind side in contact with the sea bottom where the ventral rosette is located. This study aimed to address the existing gap in specific histological, ultrastructural, lectin-histochemical and immunohistochemical studies of the turbot olfactory rosettes and olfactory bulbs. We examined microdissected olfactory organs of adult turbots and premetamorphic larvae by using routine histological staining techniques, and a wide array of lectins and primary antibodies against G-proteins and calcium-binding proteins. We observed no discernible structural variations in the olfactory epithelium between rosettes, except for the dorsal rosette being larger in size compared to the ventral rosette. Additionally, the use of transmission electron microscopy significantly improved the characterization of the adult olfactory epithelium, exhibiting high cell density, small cell size, and a wide diversity of cell types. Moreover, specific immunopositivity in sensory and non-sensory cells provided us of essential information regarding their olfactory roles. The results obtained significantly enriched the scarce morphological and neurochemical information available on the turbot olfactory system, revealing a highly complex olfactory epithelium with distinct features compared to other teleost species, especially with regard to olfactory cell distribution and immunolabelling patterns.

Conditions for establishing fin primary cell cultures in a wide range of ray-finned fishes.

Ray-finned fishes (Actinopterygii) represent the most diverse vertebrate lineage that show extensive variations in physiology, ways of life, and adaptations to marine and freshwater environments, and several species have been established as biological research models. The in vitro culture of cells is fundamental for several fields of biological research, being an alternative for studies that use animals. Hundreds of fish cell lines have been established using specific methods for each cell type and species. Here is described a protocol which can be used commonly for obtaining cell cultures from the caudal fin of a wide range of ray-finned fishes including marine and freshwater species. Conditions for sample collection, microbial disinfection, tissue dissociation, plating and incubation, cryopreservation and thawing, and karyotyping are described in detail. Primary cell cultures were developed for 20 species grouped into 12 different orders. Eleven of these species have been cultivated in vitro for the first time. In the beginning, the fish cell cultures showed different capacities of proliferation among them; however throughout the passages, most cultures began to have a similar proliferation rate. Throughout the passages, it was noticed that cells similar to fibroblasts began to predominate. The great proliferative ability of these cultures reveals their potential to become cell lines. The culture of A. mexicanus, for example, has been proliferating for months and is already in its 65th passage. Moreover, these cell cultures showed conserved diploid chromosome numbers in comparison with in vivo descriptions which suggest these cultures have stable karyotypes. Therefore, these cultures have potential to be used in several fields, such as toxicology, cytogenetics, genomics, pathology, immunology, cellular agriculture, and conservation, and this method has the potential to be expanded to species not yet tested, as well as to other organs.

Feature-Agnostic Metabolomics for Determining Effective Sub-cytotoxic Doses of Common Pesticides in Human Cells.

While classical molecular biology assays can provide a measure of cellular response to chemical challenges, they rely on a single biological phenomenon to infer a broader measure of cellular metabolic response. These methods do not always afford the necessary sensitivity to answer questions of sub-cytotoxic effects, nor do they work for all cell types. Likewise, boutique assays such as cardiomyocyte beat rate may indirectly measure cellular metabolic response, but they too, are limited to measuring a specific biological phenomenon and are often limited to a single cell type. For these reasons, toxicological researchers need new approaches to determine metabolic changes across various doses in differing cell types, especially within the low-dose regime. The data collected herein demonstrate that LC-MS/MS-based untargeted metabolomics with a feature-agnostic view of the data, combined with a suite of statistical methods including an adapted environmental threshold analysis, provides a versatile, robust, and holistic approach to directly monitoring the overall cellular metabolomic response to pesticides. When employing this method in investigating two different cell types, human cardiomyocytes and neurons, this approach revealed separate sub-cytotoxic metabolomic responses at doses of 0.1 µM and 1 µM of chlorpyrifos and carbaryl. These findings suggest that this agnostic approach to untargeted metabolomics can provide a new tool for determining effective dose by metabolomics (EDm) of chemical challenges, such as pesticides, in a direct measurement of metabolomic response that is not cell type-specific or observable using traditional assays.

Engineered exosomes with a photoinducible protein delivery system enable CRISPR-Cas-based epigenome editing in Alzheimer's disease.

Effective intracellular delivery of therapeutic proteins can potentially treat a wide array of diseases. However, efficient delivery of functional proteins across the cell membrane remains challenging. Exosomes are nanosized vesicles naturally secreted by various types of cells and may serve as promising nanocarriers for therapeutic biomolecules. Here, we engineered exosomes equipped with a photoinducible cargo protein release system, termed mMaple3-mediated protein loading into and release from exosome (MAPLEX), in which cargo proteins can be loaded into the exosomes by fusing them with photocleavable protein (mMaple3)-conjugated exosomal membrane markers and subsequently released from the exosomal membrane by inducing photocleavage with blue light illumination. Using this system, we first induced transcriptional regulation by delivering octamer-binding transcription factor 4 and SRY-box transcription factor 2 to fibroblasts in vitro. Second, we induced in vivo gene recombination in Cre reporter mice by delivering Cre recombinase. Last, we achieved targeted epigenome editing in the brains of 5xFAD and 3xTg-AD mice, two models of Alzheimer's disease. Administration of MAPLEXs loaded with β-site amyloid precursor protein cleaving enzyme 1 (Bace1)-targeting single guide RNA-incorporated dCas9 ribonucleoprotein complexes, coupled with the catalytic domain of DNA methyltransferase 3A, resulted in successful methylation of the targeted CpG sites within the Bace1 promoter. This approach led to a significant reduction in Bace1 expression, improved recognition memory impairment, and reduced amyloid pathology in 5xFAD and 3xTg-AD mice. These results suggest that MAPLEX is an efficient intracellular protein delivery system that can deliver diverse therapeutic proteins for multiple diseases.

The construction of stem cell-induced hepatocyte model and its application in evaluation of developmental hepatotoxicity of environmental pollutants.

Stem cells, with their ability to self-renew and differentiate into various cell types, are a unique and valuable resource for medical research and toxicological studies. The liver is the most crucial metabolic organ in the human body, and serves as the primary site for the accumulation of environmental pollutants. Enrichment with environmental pollutants can disrupt the early developmental processes of the liver and have a significant impact on liver function. The liver comprises a complex array of cell types, and different environmental pollutants have varying effects on these cells. Currently, there is a lack of well-established research models that can effectively demonstrate the mechanisms by which environmental pollutants affect human liver development. The emergence of liver cells and organoids derived from stem cells offers a promising tool for investigating the impact of environmental pollutants on human health. Therefore, this study systematically reviewed the developmental processes of different types of liver cells and provided an overview of studies on the developmental toxicity of various environmental pollutants using stem cell models.

MXene-Polydopamine-antiCEACAM1 Antibody Complex as a Strategy for Targeted Ablation of Melanoma.

Photothermal therapy (PTT) is a method for eradicating tumor tissues through the use of photothermal materials and photosensitizing agents that absorb light energy from laser sources and convert it into heat, which selectively targets and destroys cancer cells while sparing healthy tissue. MXenes have been intensively investigated as photosensitizing agents for PTT. However, achieving the selectivity of MXenes to the tumor cells remains a challenge. Specific antibodies (Ab) against tumor antigens can achieve homing of the photosensitizing agents toward tumor cells, but their immobilization on MXene received little attention. Here, we offer a strategy for the selective ablation of melanoma cells using MXene-polydopamine-antiCEACAM1 Ab complexes. We coated Ti3C2Tx MXene with polydopamine (PDA), a natural compound that attaches Ab to the MXene surface, followed by conjugation with an anti-CEACAM1 Ab. Our experiments confirm the biocompatibility of the Ti3C2Tx-PDA and Ti3C2Tx-PDA-antiCEACAM1 Ab complexes across various cell types. We also established a protocol for the selective ablation of CEACAM1-positive melanoma cells using near-infrared irradiation. The obtained complexes exhibit high selectivity and efficiency in targeting and eliminating CEACAM1-positive melanoma cells while sparing CEACAM1-negative cells. These results demonstrate the potential of MXene-PDA-Ab complexes for cancer therapy. They underline the critical role of targeted therapies in oncology, offering a promising avenue for the precise and safe treatment of melanoma and possibly other cancers characterized by specific biomarkers. Future research will aim to refine these complexes for clinical use, paving the way for new strategies for cancer treatment.

Compartmentalization in cardiomyocytes modulates creatine kinase and adenylate kinase activities.

Intracellular molecules are transported by motor proteins or move by diffusion resulting from random molecular motion. Cardiomyocytes are packed with structures that are crucial for function, but also confine the diffusional spaces, providing cells with a means to control diffusion. They form compartments in which local concentrations are different from the overall, average concentrations. For example, calcium and cyclic AMP are highly compartmentalized, allowing these versatile second messengers to send different signals depending on their location. In energetic compartmentalization, the ratios of AMP and ADP to ATP are different from the average ratios. This is important for the performance of ATPases fuelling cardiac excitation-contraction coupling and mechanical work. A recent study suggested that compartmentalization modulates the activity of creatine kinase and adenylate kinase in situ. This could have implications for energetic signaling through, for example, AMP-activated kinase. It highlights the importance of taking compartmentalization into account in our interpretation of cellular physiology and developing methods to assess local concentrations of AMP and ADP to enhance our understanding of compartmentalization in different cell types.

A spatial expression atlas of the adult human proximal small intestine.

The mouse small intestine shows profound variability in gene expression along the crypt-villus axis1,2. Whether similar spatial heterogeneity exists in the adult human gut remains unclear. Here we use spatial transcriptomics, spatial proteomics and single-molecule fluorescence in situ hybridization to reconstruct a comprehensive spatial expression atlas of the adult human proximal small intestine. We describe zonated expression and cell type representation for epithelial, mesenchymal and immune cell types. We find that migrating enterocytes switch from lipid droplet assembly and iron uptake at the villus bottom to chylomicron biosynthesis and iron release at the tip. Villus tip cells are pro-immunogenic, recruiting γδ T cells and macrophages to the tip, in contrast to their immunosuppressive roles in mouse. We also show that the human small intestine contains abundant serrated and branched villi that are enriched at the tops of circular folds. Our study presents a detailed resource for understanding the biology of the adult human small intestine.

Chondrogenic potential of superficial versus cartilage layer cells of the temporomandibular joint condyle in photopolymerizable gelatin-based hydrogels.

The objectives of this study were to compare the chondrogenic potential of cells derived from different layers of Mandibular condyle cartilage and to gain further understanding of the impact of chondrogenic cues when embedded into a novel hydrogel scaffold (PGH, a polymer blend of poly (ethylene glycol), gelatin, and heparin) compared to a gelatin hydrogel scaffold (GEL). Cartilage layer cells (CLCs) and fibroblastic superficial layer cells (SLCs) were harvested from the mandibular condyle of boer goats obtained from a local abattoir. After expansion, cells were seeded into PGH and GEL hydrogels and cultured in chondrogenic media for 3 weeks. Scaffolds were harvested at 0, 1, and 3 week(s) and processed for gross appearance, histochemical, biochemical, and mechanical assays. In terms of chondrogenesis, major differences were observed between scaffold materials, but not cell types. Glycosaminoglycan (GAG) staining showed GEL scaffolds deposited GAG during the 3 week period, which was also confirmed with the biochemical testing. Moreover, GEL scaffolds had significantly higher compressive modulus and peak stress than PGH scaffolds at all time points with the largest difference seen in week 3. It can be concluded that GEL outperformed PGH in chondrogenesis. It can also be concluded that materials play a more important role in the process of chondrogenesis than the tested cell populations. Fibroblastic SLCs were shown to have similar chondrogenic potential as CLCs cells, suggesting a rich pool of progenitor cells in the superficial fibroblastic layer capable of undergoing chondrogenesis given appropriate physical and chemical cues.

Anatomy, Histology, and Embryonic Origin of Adipose Tissue: Insights to Understand Adipose Tissue Homofunctionality in Regeneration and Therapies.

Preadipocytes are formed during the 14th and 16th weeks of gestation. White adipose tissue, in particular, is generated in specific areas and thereby assembles after birth, rapidly increasing following the propagation of adipoblasts, which are considered the preadipocyte cell precursors. The second trimester of gestation is a fundamental phase of adipogenesis, and in the third trimester, adipocytes, albeit small may be present within the main deposition areas. In the course of late gestation, adipose tissue develops in the foetus and promotes the synthesis of large amounts of uncoupling protein 1, in similar quantities relative to differentiated brown adipose tissue. In mammals, differentiation occurs in two functionally different types of adipose cells: white adipose cells resulting from lipid storage and brown adipose cells from increased metabolic energy consumption. During skeletogenesis, synovial joints develop through the condensation of mesenchymal cells, which forms an insertional layer of flattened cells that umlaut skeletal elements, by sharing the same origin in the development of synovium. Peri-articular fat pads possess structural similarity with body subcutaneous white adipose tissue; however, they exhibit a distinct metabolic function due to the micro-environmental cues in which they are embedded. Fat pads are an important component of the synovial joint and play a key role in the maintenance of joint homeostasis. They are also implicated in pathological states such as osteoarthritis.In this paper we explorethe therapeutic potential of adipocyte tissue mesenchymal precursor-based stem cell therapy linking it back tothe anatomic origin of adipose tissue.

Plain language summary of the CARTITUDE-4 study of ciltacabtagene autoleucel for the treatment of people with relapsed or refractory multiple myeloma.

This is a summary of a phase 3 clinical trial called CARTITUDE-4. This trial compared the anti-cancer therapy ciltacabtagene autoleucel (or cilta-cel) with standard therapies in people who have multiple myeloma, a cancer that affects specific kinds of blood cells called plasma cells. The people in the study had been treated with 1 to 3 previous treatments for multiple myeloma, including a common anti-myeloma treatment called lenalidomide, but their multiple myeloma did not get better. About half of the 419 participants in this study received cilta-cel, while the other half received standard therapies, or therapies that are commonly used to treat multiple myeloma. Participants who received cilta-cel had a type of immune cell called T cells collected from their blood and genetically modified to recognize a specific protein found on myeloma cells. These modified T cells, which comprise cilta-cel, were then infused back into the bloodstream. After approximately 1year in the study, more participants were alive without their cancer getting worse in the cilta-cel group (76%) than in the standard therapies group (49%). The most common side effects in both groups were infections and low blood cell counts. Cytokine release syndrome (a potentially serious side effect caused by overactivation of the immune system) was common but mostly mild. Neurotoxicities (including immune effector cell-associated neurotoxicity syndrome, which can cause symptoms such as headaches, changes in consciousness, and difficulty with memory, attention, speaking, or understanding others) were less common and were reported in 20.5% of participants treated with cilta-cel. In CARTITUDE-4, more participants treated with cilta-cel showed improvements and were alive with control of their disease 12months after receiving cilta-cel compared with participants who received standard therapies.Clinical Trial Registration: NCT04181827 (CARTITUDE-4) (ClinicalTrials.gov).

Lineage tracing using Wnt2b-2A-CreERT2 knock-in mice reveals the contributions of Wnt2b-expressing cells to novel subpopulations of mesothelial/epicardial cell lineages during mouse development.

Mesothelial and epicardial cells give rise to various types of mesenchymal cells via epithelial (mesothelial)-to-mesenchymal transition during development. However, the genes controlling the differentiation and diversification of mesothelial/epicardial cells remain unclear. Here, we examined Wnt2b expression in the embryonic mesothelium and epicardium and performed lineage tracing of Wnt2b-expressing cells by using novel Wnt2b-2A-CreERT2 knock-in and LacZ-reporter mice. Wnt2b was expressed in mesothelial cells covering visceral organs, but the expression was restricted in their subpopulations. Wnt2b-expressing cells labeled at embryonic day (E) 10.5 were distributed to the mesothelium and mesenchyme in the lungs, abdominal wall, stomach, and spleen in Wnt2b2A-CreERT2/+;R26RLacZ/+ mice at E13.0. Wnt2b was initially expressed in the proepicardial organ (PEO) at E9.5 and then in the epicardium after E10.0. Wnt2b-expressing PEO cells labeled at E9.5 differentiated into a small fraction of cardiac fibroblasts and preferentially localized at the left side of the postnatal heart. LacZ+ epicardium-derived cells labeled at E10.5 differentiated into a small fraction of fibroblasts and smooth muscle cells in the postnatal heart. Taken together, our results reveal novel subpopulations of PEO and mesothelial/epicardial cells that are distinguishable by Wnt2b expression and elucidate the unique contribution of Wnt2b-expressing PEO and epicardial cells to the postnatal heart.

Multi-Drug Resistance and Breast Cancer Progression via Toll-Like Receptors (TLRs) Signaling.

Toll-like receptors (TLRs) are essential receptors involved in inflammation and innate immunity. Various types of cancer cells, as well as innate immune cells, express TLRs. There is mounting proof that TLRs are critical to the development and spread of cancer as well as metabolism. In breast cancer, up-regulated levels of TLRs have been linked to the aggressiveness of the diseases, worse treatment outcomes, and the emergence of therapeutic resistance. Patients with advanced non-resectable, recurring, and metastatic breast cancer currently have few available treatment choices. An intriguing new strategy is an innate immunity-mediated anticancer immunotherapy, either used alone or in conjunction with existing treatments. In fact, several TLR agonists and antagonists have been used in clinical studies for anti-cancer immunotherapy. Consequently, TLRs serve as critical targets for controlling the course of breast cancer and treatment resistance in addition to being implicated in immune responses against pathogen infection and cancer immunology. In this review, we deliver an overview of the most current findings on TLR involvement in the development of breast cancer and treatment resistance.

Tools and methods for cell ablation and cell inhibition in Caenorhabditis elegans.

To understand the function of cells such as neurons within an organism, it can be instrumental to inhibit cellular function, or to remove the cell (type) from the organism, and thus to observe the consequences on organismic and/or circuit function and animal behavior. A range of approaches and tools were developed and used over the past few decades that act either constitutively or acutely and reversibly, in systemic or local fashion. These approaches make use of either drugs or genetically encoded tools. Also, there are acutely acting inhibitory tools that require an exogenous trigger like light. Here, we give an overview of such methods developed and used in the nematode Caenorhabditis elegans.