搜索结果: 'methocult media formulations for mouse hematopoietic cells serum containing'

BACKGROUND: Basophils are increasingly utilized as indicators of allergic inflammation and as primary allergic effector cells to study signalling pathways. However,until the present,their enrichment has been time consuming,costly and limited to relatively few specialized laboratories. OBJECTIVE: We have therefore devised a reproducible and rapid method for the purification of human basophils from small quantities of peripheral blood within 1.5 h,which does not require the use of specialized equipment such as elutriators. METHODS: Human basophils were obtained from healthy volunteers undergoing venipuncture. Heparinized or K3-ethylenediaminetetraacetic acid blood samples were first subjected to centrifugation in Hetasep,directly followed by negative selection using immunomagnetic beads. Basophil morphology and purity were assessed by May-Grünwald staining of cytospins. IgE-mediated histamine release was analysed spectrofluorometrically and IL-4 and IL-13 production by quantitative RT-PCR. CD203c and CD63 surface expression was measured using flow cytometry before and after activation with anti-IgE. RESULTS: Using this protocol,basophils were enriched close to homogeneity in most cases with a mean purity of 99.34+/-0.88% (range 97-100%,n=18) and a mean recovery of 75.6 (range 39-100%,n=8). Basophil viability following purification was 99.6+/-0.89% using Trypan blue exclusion. The purification procedure gave rise to basophils with normal functional responses to anti-IgE regarding histamine release as well as IL-4 and IL-13 mRNA expression. Moreover,constitutive cell-surface CD203c/CD63 expressions were not elevated before anti-IgE stimulation. CONCLUSION: The rapidity,simplicity and reproducibility of this method will facilitate the employment of basophils in high-output ex vivo studies. View Publication

We previously developed an antibody-avidin fusion protein (ch128.1Av) targeting the human transferrin receptor 1 (TfR1,also known as CD71),which demonstrates direct in vitro cytotoxicity against malignant hematopoietic cells. This cytotoxicity is attributed to its ability to decrease the level of TfR1 leading to lethal iron deprivation. We now report that ch128.1Av shows the ability to bind the Fcγ receptors and the complement component C1q,suggesting that it is capable of eliciting Fc-mediated effector functions such as antibody-dependent cell-mediated cytotoxicity and complement-mediated cytotoxicity. In addition,in 2 disseminated multiple myeloma xenograft mouse models,we show that a single dose of ch128.1Av results in significant antitumor activity,including long-term survival. It is interesting to note that the parental antibody without avidin (ch128.1) also shows remarkable in vivo anticancer activity despite its limited in vitro cytotoxicity. Finally,we demonstrate that ch128.1Av is not toxic to pluripotent hematopoietic progenitor cells using the long-term cell-initiating culture assay suggesting that these important progenitors would be preserved in different therapeutic approaches,including the in vitro purging of cancer cells for autologous transplantation and in vivo passive immunotherapy. Our results suggest that ch128.1Av and ch128.1 may be effective in the therapy of human multiple myeloma and potentially other hematopoietic malignancies. View Publication

Eosinophils,a type of granulocyte derived from myeloid precursors in the bone marrow,are distinguished by their cytoplasmic granules. They play crucial roles in immunoregulation,tissue homeostasis,and host defense,while also contributing to the pathogenesis of various inflammatory diseases. Although long non-coding RNAs (lncRNAs) are known to be involved in eosinophilic conditions,their specific expression and functions within eosinophils have not been thoroughly investigated,largely due to the reliance on tissue homogenates. In an effort to address this gap,we analyzed publicly available high-throughput RNA sequencing data to identify lncRNAs associated with eosinophilic conditions. Among the identified lncRNAs,ITGB2 antisense RNA 1 (ITGB2-AS1) was significantly downregulated in blood eosinophils from patients with hypereosinophilia. To further explore its role in eosinophil biology,we generated a stable ITGB2-AS1 knockdown in the HL-60 cell line. Interestingly,ITGB2-AS1 deficiency led to impaired eosinophil differentiation,as evidenced by a reduction in cytoplasmic granules and decreased expression of key eosinophil granule proteins,including eosinophil peroxidase (EPX) and major basic protein-1 (MBP-1). Additionally,ITGB2-AS1-deficient cells exhibited compromised eosinophil effector functions,with reduced degranulation and impaired production of reactive oxygen species (ROS). These findings suggest that ITGB2-AS1 plays a pivotal role in eosinophil differentiation and function,positioning it as a novel regulator in eosinophil biology. View Publication

Delivering macromolecules across biological barriers such as the blood–brain barrier limits their application in vivo. Previous work has demonstrated that Toxoplasma gondii,a parasite that naturally travels from the human gut to the central nervous system (CNS),can deliver proteins to host cells. Here we engineered T. gondii ’s endogenous secretion systems,the rhoptries and dense granules,to deliver multiple large (>100 kDa) therapeutic proteins into neurons via translational fusions to toxofilin and GRA16. We demonstrate delivery in cultured cells,brain organoids and in vivo,and probe protein activity using imaging,pull-down assays,scRNA-seq and fluorescent reporters. We demonstrate robust delivery after intraperitoneal administration in mice and characterize 3D distribution throughout the brain. As proof of concept,we demonstrate GRA16-mediated brain delivery of the MeCP2 protein,a putative therapeutic target for Rett syndrome. By characterizing the potential and current limitations of the system,we aim to guide future improvements that will be required for broader application. Subject terms: Parasitology,Biologics,Synthetic biology View Publication

Metastasis is one of the leading causes of cancer-related death worldwide. Fascin,a protein that bundles actin filaments to produce protrusions in cancer cells,plays a significant role in the enhancement of cell migration. This protein has been shown that the overexpression of this protein is related to the appearance of different types of cancer,such as colorectal cancer. In this study,we conducted in silico screening of the Enamine library,a compound library with a broad chemical space. Using a ligand-based virtual screening approach based on the pharmacophore model of G2,we identified the predicted inhibitors. First,these compounds were validated by physicochemical analysis. Differential scanning calorimetry (DSF) was used to study the binding between the predicted compounds and fascin protein,followed by an F-actin bundling assay to determine which compounds inhibited the bundling function of fascin. Z1362873773,which exhibited binding to fascin and inhibited F-actin bundling,was further tested in cell cultures to assess its effects on cancer cell viability and migration as well as in organoid models to evaluate potential cytotoxicity. Finally,we established a protocol that can be applied to discover anti-fascin agents from diverse compound libraries. A new molecule has been identified with considerable fascin inhibitory and migration-arresting capacity,which may lead to the development of new therapies to treat cancer. The online version contains supplementary material available at 10.1038/s41598-025-96457-x. Subject terms: Biochemistry,Biophysics,Cancer,Drug discovery,Molecular biology,Virtual drug screening View Publication

Suspension bath bioprinting,whereby bioinks are extruded into a yield stress bath with rapid recovery from shearing,has enabled the printing of low viscosity bioinks into constructs with high geometric complexity. Previous studies have often relied upon external stabilisation of the suspension bath (e.g. collagen) in order to culture soft materials without loss of printed structure. Here,we report a systematic investigation of suspension bath properties that support the printing,fusion,and culture of spheroid-based bioinks without added stabilisation. Specifically,agarose fluid gels of varied polymer concentrations and dilutions were produced and characterised morphologically and rheologically. Juvenile bovine chondrocytes or mesenchymal stromal cells (MSCs) were formed into spheroids of ∼150 µ m in diameter and investigated within agarose suspension baths either for their fusion in hanging drop cultures or as jammed bioinks. MSC spheroids were also printed when mixed with hydrogel microparticles to demonstrate additional versatility to the approach. Suspension baths of lower polymer concentrations and increased dilution enabled faster spheroid fusion; however,the most heavily diluted suspension bath was unable to maintain print fidelity. Other formulations supported the printing,fusion,and culture of spheroid-based inks,either as simple lines or more complex patterns. These findings help to inform the design of suspension baths for bioprinting and culture. View Publication

Several recent reports suggest that there is far more plasticity that previously believed in the developmental potential of bone-marrow-derived cells (BMCs) that can be induced by extracellular developmental signals of other lineages whose nature is still largely unknown. In this study,we demonstrate that bone-marrow-derived mesenchymal stem cells (MSCs) co-cultured with mouse proliferating or fixed (by paraformaldehyde or methanol) neural stem cells (NSCs) generate neural stem cell-like cells with a higher expression of Sox-2 and nestin when grown in NS-A medium supplemented with N2,NSC conditioned medium (NSCcm) and bFGF. These neurally induced MSCs eventually differentiate into beta-III-tubulin and GFAP expressing cells with neuronal and glial morphology when grown an additional week in Neurobasal/B27 without bFGF. We conclude that juxtacrine interaction between NSCs and MSCs combined with soluble factors released from NSCs are important for generation of neural-like cells from bone-marrow-derived adherent MSCs. View Publication

The molecular basis for the unique proliferative and self-renewal properties that hierarchically distinguish human stem cells from progenitors and terminally differentiated cells remains largely unknown. We report a role for the Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) as an indispensable regulator of self-renewal in human stem cells and show that a functional dependence on Mcl-1 defines the human stem cell hierarchy. In vivo pharmacologic targeting of the Bcl-2 family members in human hematopoietic stem cells (HSCs) and human leukemic stem cells reduced stem cell regenerative and self-renewal function. Subsequent protein expression studies showed that,among the Bcl-2 family members,only Mcl-1 was up-regulated exclusively in the human HSC fraction on in vivo regeneration of hematopoiesis. Short hairpin RNA-knockdown of Mcl-1 in human cord blood cells did not affect survival in the HSC or hematopoietic progenitor cell fractions in vitro but specifically reduced the in vivo self-renewal function of human HSCs. Moreover,knockdown of Mcl-1 in ontogenetically primitive human pluripotent stem cells resulted in almost complete ablation of stem cell self-renewal function. Our findings show that Mcl-1 is an essential regulator of stem cell self-renewal in humans and therefore represents an axis for therapeutic interventions. View Publication

There is evidence that neutrophil production is a balance between the proliferative action of granulocyte-colony-stimulating factor (G-CSF) and a negative feedback from mature neutrophils (the chalone). Two neutrophil serine proteases have been implicated in granulopoietic regulation: pro-proteinase 3 inhibits granulocyte macrophage-colony-forming unit (CFU-GM) growth,and elastase mutations cause cyclic and congenital neutropenia. We further studied the action of the neutrophil serine proteases (proteinase 3,elastase,azurocidin,and cathepsin G) on granulopoiesis in vitro. Elastase inhibited CFU-GM in methylcellulose culture. In serum-free suspension cultures of CD34+ cells,elastase completely abrogated the proliferation induced by G-CSF but not that of GM-CSF or stem cell factor (SCF). The blocking effect of elastase was prevented by inhibition of its enzymatic activity with phenylmethylsulfonyl fluoride (PMSF) or heat treatment. When exposed to enzymatically active elastase,G-CSF,but not GM-CSF or SCF,was rapidly cleaved and rendered inactive. These results support a role for neutrophil elastase in providing negative feedback to granulopoiesis by direct antagonism of G-CSF. View Publication

Monomeric clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated 9 (Cas9) nucleases have been widely adopted for simple and robust targeted genome editing but also have the potential to induce high-frequency off-target mutations. In principle,two orthogonal strategies for reducing off-target cleavage,truncated guide RNAs (tru-gRNAs) and dimerization-dependent RNA-guided FokI-dCas9 nucleases (RFNs),could be combined as tru-RFNs to further improve genome editing specificity. Here we identify a robust tru-RFN architecture that shows high activity in human cancer cell lines and embryonic stem cells. Additionally,we demonstrate that tru-gRNAs reduce the undesirable mutagenic effects of monomeric FokI-dCas9. Tru-RFNs combine the advantages of two orthogonal strategies for improving the specificity of CRISPR-Cas nucleases and therefore provide a highly specific platform for performing genome editing. View Publication