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

Automation and quality control (QC) are critical in manufacturing safe and effective cell and gene therapy products. However,current QC methods,reliant on molecular staining,pose difficulty in in-line testing and can increase manufacturing costs. Here we demonstrate the potential of using label-free ghost cytometry (LF-GC),a machine learning-driven,multidimensional,high-content,and high-throughput flow cytometry approach,in various stages of the cell therapy manufacturing processes. LF-GC accurately quantified cell count and viability of human peripheral blood mononuclear cells (PBMCs) and identified non-apoptotic live cells and early apoptotic/dead cells in PBMCs (ROC-AUC: area under receiver operating characteristic curve = 0.975),T cells and non-T cells in white blood cells (ROC-AUC = 0.969),activated T cells and quiescent T cells in PBMCs (ROC-AUC = 0.990),and particulate impurities in PBMCs (ROC-AUC ≧ 0.998). The results support that LF-GC is a non-destructive label-free cell analytical method that can be used to monitor cell numbers,assess viability,identify specific cell subsets or phenotypic states,and remove impurities during cell therapy manufacturing. Thus,LF-GC holds the potential to enable full automation in the manufacturing of cell therapy products with reduced cost and increased efficiency. Subject terms: Biotechnology,Cell biology,Immunology,Biomedical engineering View Publication

Genome editing using CRISPR-Cas systems is a promising avenue for the treatment of genetic diseases. However,cellular and humoral immunogenicity of genome editing tools,which originate from bacteria,complicates their clinical use. Here we report reduced immunogenicity (Red)(i)-variants of two clinically relevant nucleases,SaCas9 and AsCas12a. Through MHC-associated peptide proteomics (MAPPs) analysis,we identify putative immunogenic epitopes on each nuclease. Using computational modeling,we rationally design these proteins to evade the immune response. SaCas9 and AsCas12a Redi variants are substantially less recognized by adaptive immune components,including reduced binding affinity to MHC molecules and attenuated generation of cytotoxic T cell responses,yet maintain wild-type levels of activity and specificity. In vivo editing of PCSK9 with SaCas9.Redi.1 is comparable in efficiency to wild-type SaCas9,but significantly reduces undesired immune responses. This demonstrates the utility of this approach in engineering proteins to evade immune detection. Subject terms: Protein design,Immunogenetics,CRISPR-Cas9 genome editing View Publication

Respiratory organoids have emerged as a powerful in vitro model for studying respiratory diseases and drug discovery. However,the high-throughput analysis of organoid images remains a challenge due to the lack of automated and accurate segmentation tools. This study presents a semi-automatic algorithm for image analysis of respiratory organoids (nasal and lung organoids),employing the U-Net architecture and CellProfiler for organoids segmentation. The algorithm processes bright-field images acquired through z-stack fusion and stitching. The model demonstrated a high level of accuracy,as evidenced by an intersection-over-union metric (IoU) of 0.8856,F1-score = 0.937 and an accuracy of 0.9953. Applied to forskolin-induced swelling assays of lung organoids,the algorithm successfully quantified functional differences in Cystic Fibrosis Transmembrane conductance Regulator (CFTR)-channel activity between healthy donor and cystic fibrosis patient-derived organoids,without fluorescent dyes. Additionally,an open-source dataset of 827 annotated respiratory organoid images was provided to facilitate further research. Our results demonstrate the potential of deep learning to enhance the efficiency and accuracy of high-throughput respiratory organoid analysis for future therapeutic screening applications. Author summaryIn this study,we developed a semi-automated tool to analyze images of respiratory organoids—3D cell structures that mimic the human respiratory system. These organoids are vital for studying diseases like cystic fibrosis and testing potential drugs,but manually analyzing their images is time-consuming and prone to errors. Our tool uses artificial intelligence (AI) to quickly and accurately measure organoid size and shape from bright-field microscope images,eliminating the need for fluorescent dyes that can harm cells. We trained our AI model on a publicly shared dataset of 827 annotated organoid images,achieving high accuracy in detecting and quantifying organoids. When applied to cystic fibrosis research,the tool successfully measured differences in organoid swelling (forskolin-induced swelling - a key test for drug response) between healthy and patient-derived samples. By making our dataset and method openly available,we hope to support further research into respiratory diseases. Our work bridges the gap between complex lab techniques and practical applications,offering a faster,more reliable way to study human health and disease. View Publication

RNA-binding motif protein 15 (RBM15) is involved in the RBM15-megakaryoblastic leukemia 1 fusion in acute megakaryoblastic leukemia. Although Rbm15 has been reported to be required for B-cell differentiation and to inhibit myeloid and megakaryocytic expansion,it is not clear what the normal functions of Rbm15 are in the regulation of hematopoietic stem cell (HSC) and megakaryocyte development. In this study,we report that Rbm15 may function in part through regulation of expression of the proto-oncogene c-Myc. Similar to c-Myc knockout (c-Myc-KO) mice,long-term (LT) HSCs are significantly increased in Rbm15-KO mice due to an apparent LT-HSC to short-term HSC differentiation defect associated with abnormal HSC-niche interactions caused by increased N-cadherin and beta(1) integrin expression on mutant HSCs. Both serial transplantation and competitive reconstitution capabilities of Rbm15-KO LT-HSCs are greatly compromised. Rbm15-KO and c-Myc-KO mice also share related abnormalities in megakaryocyte development,with mutant progenitors producing increased,abnormally small low-ploidy megakaryocytes. Consistent with a possible functional interplay between Rbm15 and c-Myc,the megakaryocyte increase in Rbm15-KO mice could be partially reversed by ectopic c-Myc. Thus,Rbm15 appears to be required for normal HSC-niche interactions,for the ability of HSCs to contribute normally to adult hematopoiesis,and for normal megakaryocyte development; these effects of Rbm15 on hematopoiesis may be mediated at least in part by c-Myc. View Publication

MafB is a member of the large Maf family of transcription factors that share similar basic region/leucine zipper DNA binding motifs and N-terminal activation domains. Although it is well known that MafB is specifically expressed in glomerular epithelial cells (podocytes) and macrophages,characterization of the null mutant phenotype in these tissues has not been previously reported. To investigate suspected MafB functions in the kidney and in macrophages,we generated mafB/green fluorescent protein (GFP) knock-in null mutant mice. MafB homozygous mutants displayed renal dysgenesis with abnormal podocyte differentiation as well as tubular apoptosis. Interestingly,these kidney phenotypes were associated with diminished expression of several kidney disease-related genes. In hematopoietic cells,GFP fluorescence was observed in both Mac-1- and F4/80-expressing macrophages in the fetal liver. Interestingly,F4/80 expression in macrophages was suppressed in the homozygous mutant,although development of the Mac-1-positive macrophage population was unaffected. In primary cultures of fetal liver hematopoietic cells,MafB deficiency was found to dramatically suppress F4/80 expression in nonadherent macrophages,whereas the Mac-1-positive macrophage population developed normally. These results demonstrate that MafB is essential for podocyte differentiation,renal tubule survival,and F4/80 maturation in a distinct subpopulation of nonadherent mature macrophages. View Publication

Canine leukocyte adhesion deficiency (CLAD) represents the canine counter-part of the human disease leukocyte adhesion deficiency (LAD). Defects in the leukocyte integrin CD18 adhesion molecule in both CLAD and LAD lead to recurrent,life-threatening bacterial infections. We evaluated ex vivo retroviral-mediated gene therapy in CLAD using 2 nonmyeloablative conditioning regimens--200 cGy total body irradiation (TBI) or 10 mg/kg busulfan--with or without posttransplantation immunosuppression. In 6 of 11 treated CLAD dogs,therapeutic levels of CD18(+) leukocytes were achieved. Conditioning with either TBI or busulfan allowed long-term engraftment,and immunosuppression was not required for efficacy. The percentage of CD18(+) leukocytes in the peripheral blood progressively increased over 6 to 8 months after infusion to levels ranging from 1.26% to 8.37% at 1-year follow-up in the 6 dogs. These levels resulted in reversal or moderation of the severe CLAD phenotype. Linear amplification-mediated polymerase chain reaction assays indicated polyclonality of insertion sites. These results describe ex vivo hematopoietic stem cell gene transfer in a disease-specific,large animal model using 2 clinically applicable conditioning regimens,and they provide support for the use of nonmyeloablative conditioning regimens in preclinical protocols of retroviral-mediated gene transfer for nonmalignant hematopoietic diseases such as LAD. View Publication

Most polyreactive and antinuclear antibodies are removed from the human antibody repertoire during B cell development. To elucidate how B cell receptor (BCR) signaling may regulate human B cell tolerance,we tested the specificity of recombinant antibodies from single peripheral B cells isolated from patients suffering from X-linked agammaglobulinemia (XLA). These patients carry mutations in the Bruton's tyrosine kinase (BTK) gene that encode an essential BCR signaling component. We find that in the absence of Btk,peripheral B cells show a distinct antibody repertoire consistent with extensive secondary V(D)J recombination. Nevertheless,XLA B cells are enriched in autoreactive clones. Our results demonstrate that Btk is essential in regulating thresholds for human B cell tolerance. View Publication

NKX2-5 is expressed in the heart throughout life. We targeted eGFP sequences to the NKX2-5 locus of human embryonic stem cells (hESCs); NKX2-5(eGFP/w) hESCs facilitate quantification of cardiac differentiation,purification of hESC-derived committed cardiac progenitor cells (hESC-CPCs) and cardiomyocytes (hESC-CMs) and the standardization of differentiation protocols. We used NKX2-5 eGFP(+) cells to identify VCAM1 and SIRPA as cell-surface markers expressed in cardiac lineages. View Publication