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

The neutralization of integrin α4 (Itga4) is currently used as treatment in multiple sclerosis. Although most studies have focused on its function on lymphocyte migration to the CNS,we have uncovered the importance of Itga4 for the generation of regulatory B cells in peripheral immune organs and their control of pathogenic T cell response and CNS pathology. Our study underscores the importance of looking at the dual role of B cells in CNS autoimmunity and provides important perspectives regarding the efficacy and side effects associated with Itga4 neutralization and other B cell-targeting therapies. 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

Protein kinase B (PKB/Akt) belongs to the AGC superfamily of related serine/threonine protein kinases. It is a key regulator downstream of various growth factors and hormones and is involved in malignant transformation and chemo-resistance. Full-length PKB protein has not been crystallised,thus studying the molecular mechanisms that are involved in its regulation in relation to its structure have not been simple. Recently,the dynamics between the inactive and active conformer at the molecular level have been described. The maintenance of PKB's inactive state via the interaction of the PH and kinase domains prevents its activation loop to be phosphorylated by its upstream activator,phosphoinositide-dependent protein kinase-1 (PDK1). By using a multidisciplinary approach including molecular modelling,classical biochemical assays,and Förster resonance energy transfer (FRET)/two-photon fluorescence lifetime imaging microscopy (FLIM),a detailed model depicting the interaction between the different domains of PKB in its inactive conformation was demonstrated. These findings in turn clarified the molecular mechanism of PKB inhibition by AKT inhibitor VIII (a specific allosteric inhibitor) and illustrated at the molecular level its selectivity towards different PKB isoforms. Furthermore,these findings allude to the possible function of the C-terminus in sustaining the inactive conformer of PKB. This study presents essential insights into the quaternary structure of PKB in its inactive conformation. An understanding of PKB structure in relation to its function is critical for elucidating its mode of activation and discovering how to modulate its activity. The molecular mechanism of inhibition of PKB activation by the specific drug AKT inhibitor VIII has critical implications for determining the mechanism of inhibition of other allosteric inhibitors and for opening up opportunities for the design of new generations of modulator drugs. View Publication

This report describes an international prevalidation study conducted to optimise the Standard Operating Procedure (SOP) for detecting myelosuppressive agents by CFU-GM assay and to study a model for predicting (by means of this in vitro hematopoietic assay) the acute xenobiotic exposure levels that cause maximum tolerated decreases in absolute neutrophil counts (ANC). In the first phase of the study (Protocol Refinement),two SOPs were assessed,by using two cell culture media (Test A,containing GM-CSF; and Test B,containing G-CSF,GM-CSF,IL-3,IL-6 and SCF),and the two tests were applied to cells from both human (bone marrow and umbilical cord blood) and mouse (bone marrow) CFU-GM. In the second phase (Protocol Transfer),the SOPs were transferred to four laboratories to verify the linearity of the assay response and its interlaboratory reproducibility. After a further phase (Protocol Performance),dedicated to a training set of six anticancer drugs (adriamycin,flavopindol,morpholino-doxorubicin,pyrazoloacridine,taxol and topotecan),a model for predicting neutropenia was verified. Results showed that the assay is linear under SOP conditions,and that the in vitro endpoints used by the clinical prediction model of neutropenia are highly reproducible within and between laboratories. Valid tests represented 95% of all tests attempted. The 90% inhibitory concentration values (IC(90)) from Test A and Test B accurately predicted the human maximum tolerated dose (MTD) for five of six and for four of six myelosuppressive anticancer drugs,respectively,that were selected as prototype xenobiotics. As expected,both tests failed to accurately predict the human MTD of a drug that is a likely protoxicant. It is concluded that Test A offers significant cost advantages compared to Test B,without any loss of performance or predictive accuracy. On the basis of these results,we proposed a formal Phase II validation study using the Test A SOP for 16-18 additional xenobiotics that represent the spectrum of haematotoxic potential. View Publication

In the present study,we combined stem cell technology with a non-absorbable biomaterial for the reconstruction of the ruptured ACL. Towards this purpose,multipotential stromal cells derived either from subcutaneous human adipose tissue (hAT-MSCs) or from induced pluripotent stem cells (iPSCs) generated from human foreskin fibroblasts (hiPSC-MSCs) were cultured on the biomaterial for 21days in vitro to generate a 3D bioartifical ACL graft. Stem cell differentiation towards bone and ligament at the ends and central part of the biomaterial was selectively induced using either BMP-2/FGF-2 or TGF-β/FGF-2 combinations,respectively. The bioartificial ACL graft was subsequently implanted in a swine ACL rupture model in place of the surgically removed normal ACL. Four months post-implantation,the tissue engineered ACL graft generated an ACL-like tissue exhibiting morphological and biochemical characteristics resembling those of normal ACL. View Publication

Tunneling nanotubes (TNTs) are ultrafine,filamentous actin-based cytoplasmic extensions which form spontaneously to connect cells at short and long-range distances. We have previously described long-range intercellular communication via TNTs connecting mesothelioma cells in vitro and demonstrated TNTs in intact tumors from patients with mesothelioma. Here,we investigate the ability of TNTs to mediate a viral thymidine kinase based bystander effect after oncolytic viral infection and administration of the nucleoside analog ganciclovir. Using confocal microscopy we assessed the ability of TNTs to propagate enhanced green fluorescent protein (eGFP),which is encoded by the herpes simplex virus NV1066,from infected to uninfected recipient cells. Using time-lapse imaging,we observed eGFP expressed in infected cells being transferred via TNTs to noninfected cells; additionally,increasing fluorescent activity in recipient cells indicated cell-to-cell transmission of the eGFP-expressing NV1066 virus had also occurred. TNTs mediated cell death as a form of direct cell-to-cell transfer following viral thymidine kinase mediated activation of ganciclovir,inducing a unique long-range form of the bystander effect through transmission of activated ganciclovir to nonvirus-infected cells. Thus,we provide proof-of-principle demonstration of a previously unknown and alternative mechanism for inducing apoptosis in noninfected recipient cells. The conceptual advance of this work is that TNTs can be harnessed for delivery of oncolytic viruses and of viral thymidine kinase activated drugs to amplify the bystander effect between cancer cells over long distances in stroma-rich tumor microenvironments. View Publication