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We narrowed to 1,027 results for: ELL

Showing: 331 - 360 of 1027 results
  1. Hot Plasmids - June 2019 - Optogenetics, Acoustic Reporter Genes, microRNAs, and the CRISPR-Cas9 system CHIME

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    ...efficient gene deletion in B cells, T cells, macrophages, and dendritic cells, with no deleterious effects...to HEK293FT and HeLa cell lines. When the miRNA activity profile for a given cell type is already known...or ZFN to edit immune cells poses challenges such as the inhibition of immune cell differentiation. Furthermore...immune cell activity. However, a CRISPR-based tool for in vivo functional analysis of immune cells has been...construct in bone marrow stem cells from Cas9-expressing mice, and used the cells to reconstitute the immune...vivo using ultrasound in Escherichia coli and Salmonella Typhimurium. This work demonstrates engineered...post-transcriptional gene expression across the majority of cellular pathways. Despite several years of research, the...
  2. New Tools Enable CRISPRa for Neuroscience Applications

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    ...fluorescence activated cell sorting (FACS) to isolate differentiated from undifferentiated cells at the end of ...these cell types are used. The lack of good flow cytometric antibodies for many CNS-resident cell types...for which CRISPRa is well-suited, including studying mRNA dosing effects, cellular reprogramming, and disease...that drive neuronal fate and reprogramming." Cell stem cell 23.5 (2018): 758-771. PubMed PMID: 30318302...-Rhodes, a Ruth L. Kirschstein NRSA Predoctoral Fellow at University of Rochester Medical Center. During...relationships in defined substructures of the CNS as well as individual neuronal populations.  The Yang Lab...lentiviral vectors for in vitro and in vivo CRISPRa (Savell et al., 2019). This dual lentivirus system pairs...
  3. Advanced Uses of Cre-lox and Flp-FRT - A Neuroscientist’s View

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    ...specific cell types (populations) within neuronal networks in living animals. To accomplish such cell specific...individual cells. With this technique, a Neuroscientist can see the full dendritic arbor of a single cell with...Cre-mediated possibilities for site specific (and often cell type specific) control of DNA recombination and ...expression can be advanced by the coordinated use of fellow SSR system FLP-FRT. In addition, a variety of means...30 °C and is therefore inefficient in mammalian cells (usually grown at 37 °C). Smart molecular evolution...revolutionize neuroscience Manipulation of specific cell types in neuronal networks Double inverted vectors...combination with mouse lines that express Cre only in the cell type of interest (Atasoy et al. 2008; Cardin et ...
  4. Hot Plasmids April 2018 - Protein Degradation, Nanoscopy, FIRE-Cas9, and Yeast Expression Tools

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    ...proteins in ten ddifferent cell types, including difficult-to-manipulate primary cells, achieving knockdown ...stable cell lines overexpressing TRIM21, finding that TRIM21 overexpression did not affect cell proliferation... small cell populations, co-microinjection of TRIM21 protein and the target antibody works well. In larger...electroporated cells re-adhered to the culture plate within 4 hr of treatment. In some primary cell lines, endogenous...proliferation. These cells also did not contain changes in expression of TRIM21-associated genes, indicating...larger cell populations, you can deliver these components together using electroporation. In these bulk...bulk cell experiments, Clift et al. observed no stress or damage upon TRIM-Away, and the electroporated...
  5. Antibodies 101: Validation

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    ...look at the subcellular localization of a protein of interest. Conveniently, you found a cell line in which...perform immunocytochemistry on these mutant cells as well as a non-mutant line and see a great antibody...antibody binding in the transfected cells but not in control cells. But (there is always a ‘but’), you...transfect it into your favorite cell line. In parallel, you transfect cells with another plasmid not encoding...the cells transfected with your protein of interest and show just the faintest band from the cells transfected...or may not perform well under the same conditions. Example: You want to sort cells based on the expression...when you start using complex samples such as whole cell lysate or tissue sections. It is important to confirm...
  6. Four Ways to Package Transgenes That Exceed the Size Limit of Adeno-associated Virus

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    ...human T cells and hematopoietic stem and progenitor cells (HSPC)s to ~40% expression in the K562 cell line....201302948 Trapani I, Toriello E, de Simone S, Colella P, Iodice C, Polishchuk EV, Sommella A, Colecchi L, Rossi...gene to airway epithelial cells in mice. This vector transduced ~10% of cells, similar to the transduction...//doi.org/10.1038/mt.2010.205 Trapani I, Colella P, Sommella A, Iodice C, Cesi G, Simone S, Marrocco E... then independently packaged into an AAV. When a cell is co-infected with both part A and part B AAVs,... always.  The combination of serotype and tissue/cell type could have a big impact on the rate of transgene...since both of these variables influence whether cells will be co-transduced with multiple copies of both...
  7. Plasmids 101: Knockout/Knock-In Plasmids

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    ...recombined cells. Recombination is a rare event, so you must select as opposed to screen for cells where recombination...Correctly recombined cells will not contain the negative selection marker, but cells with random recombination...modified version of the targeted sequence to the cell which will recombine the template with the endogenous... used to inactivate specific genes in mammalian cells. Despite the popularity of CRISPR-based knockout...targeting construct. For recombination to occur in a cell, a minimum of 2 kb of sequence homology is required...antibiotic resistance gene. To avoid selecting for cells in which the construct has randomly integrated into...outside one of the homology arms. When we select cells later, we will first perform a positive selection...
  8. Deep Dive: Fixing and Permeabilizing for Immunofluorescence

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    ...holes in the cell membranes of your sample to allow antibodies better access to intracellular targets. If...allowing antibodies into the cell where they could bind to intracellular epitopes. C) Permeabilizing with...method for visualizing molecules of interest within a cell or tissue. In that introduction, we broke down the...structure of your samples, the relationships between cellular components, and the accessibility of your target...cross-linkers work by (as the name suggests) cross-linking cellular proteins. Cross-linking is a chemical reaction...great for preserving your samples and maintaining cellular and tissue morphology. Formaldehyde is the most...37%). Formalin solutions often contain methanol as well, in order to slow the polymerization of formaldehyde...
  9. Live and Let Dye: Self-Labeling Protein Tags

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    ...mitochondria reveals dynamic organelle interactions. a) Labeling scheme. b) COS-7 cell ER labeled with Halo-Sec61β...Bewersdorf, J. (2016). Two-colour live-cell nanoscale imaging of intracellular targets. Nature Communications,...better-dyeing-through-chemistry-small-molecule-fluorophores  Los, G. V., Encell, L. P., McDougall, M. G., Hartzell, D. D., Karassina, N., Zimprich...opening up new applications.   Figure 1: Live-cell labeling strategies. The green structure represents...standard confocal microscopy. Image adapted from (Bottanelli et al., 2016) under CC-BY license. Combining... HaloTag for their "ticker tape" method for intracellular recordings, switching between different colored...649-mDia1, magenta) and capping protein (549-CP, yellow) at the tip. 649-mDia1 and 549-CP are both SNAP-tag...
  10. Plasmids 101: Screens vs. Selections

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    ...culture cells in the drug of interest at a lethal dose for non-manipulated cells and then assay cells which...considering either a cellular screen or a selection. A selection is a process in which only cells with the trait...selection, you might put cells into a drug-containing media in which only cells which can tolerate the ... – that is, you are not specifically looking at cells that can survive. Instead, all manipulations are...off. For a screen, you would individually treat cells with many different drugs and then perform an assay...manipulating or mutagenizing a population (typically cells or small organisms) and then assaying for a functional...For example, a drug screen may be performed on a cell line possessing a patient mutation to assess how...
  11. Antibodies 101: Isotypes

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    ...the surface of basophils and mast cells, two types of white blood cells involved in allergic reactions. ...determines several key characteristics of an antibody as well as the role it plays in an immune response. But ... is important because it determines what immune cells and molecules are recruited by the antibody to help...each of these functions: Recruitment of immune cells that express receptors that recognize the Fc portion...which can initiate a cascade that helps attack extracellular pathogens.  Transportation of antibodies to ...special receptors that transport antibodies through cells and into different body compartments, such as into...isotype nomenclature. Antibody heavy chain proteins as well as the genes that encode those proteins are designated...
  12. Plasmids 101: Yeast Vectors

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    ...within an E. coli cell, but vectors can be widely utilized across many different cell types and each one... the yeast cell. These elements control not only the number of plasmids found in each cell, but also whether...are eukaryotes and thus contain complex internal cell structures similar to those of plants and animals... ease of replica plating and mutant isolation, a well-defined genetic system, and a highly versatile DNA...diploid state which is useful for genetic analysis, as well as an efficient mechanism of homologous recombination...components to allow shuttling between E. coli and yeast cells. To be useful in the lab, the vectors must contain...replication (ORI) and a means of selection in yeast cells, in addition to the bacterial ORI and antibiotic...
  13. Advancing Biology with Zebrafish: Genetic Tools for Developmental Studies and More

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    ...development. Single cell sequencing-based lineage tracing Recently, gene expression in all cells of the developing...gene activity and cell divisions that coordinate development of the body plan (Farrell et al., 2018). This...proportions of otherwise normal cell types are produced, rather than novel, abnormal cell types. Sequencing-based...): 193. PubMed PMID: 30944477. Farrell, Jeffrey A., et al. "Single-cell reconstruction of developmental...applications. For example, specific tissues such as blood cells or neurons can be fluorescently labeled, allowing...Strategies for generating transgenic zebrafish are well established (Felker and Mosimann, 2016). One common...divisions, and movements of each of the thousands of cells in the developing zebrafish embryo have been tracked...
  14. dTAG - You're it!

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    ...dTAG molecule toxicity in new cell lines Treat parental cells (or cells expressing a control -- for example...contributed by guest blogger Behnam Nabet, a postdoctoral fellow at Dana-Farber Cancer Institute. Targeted protein...dTAG system is versatile and can be used in both cell-based assays and mouse models. The dTAG system The...broad utility for degrading targets in different cellular compartments, and in vivo utility. dTAG molecules...of N- and C-terminal fusions and degradation in a cell line of interest prior to starting knock-in experiments...the FKBP12F36V-fusion chimera of interest. In the cell lines we have evaluated to date, we observed little...different contexts (for example, IZKF1 and IZKF3 are cell-type specific transcription factors with important...
  15. It’s Bioelectric! An Exciting Interdisciplinary Field of Research

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    ...for neurons. Non-neuronal cells do this too. It's just that for non-neural cells, ion-based communication...between many cells (through gap junction proteins which connect the cytoplasm of two cells) can also affect...more depolarized (positive) the cell is, the more embryonic, stem cell-like, or cancerous it is (Levin...happens at a slightly slower scale.  All living cells with a membrane possess an electrical state. This...charge between the inside and the outside of the cell. This imbalance is maintained by ion channels and...when I attended the Developmental Bioelectricity satellite symposium at the 2019 Society for Developmental...proteins cx43 GJB1 GJB2 Bioelectric states can alter cell types and patterning There is mounting evidence ...
  16. Important Considerations When Using AAVs

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    ...to us? Well, an AAV user must determine which serotype is most efficient at transducing the cell type under...optogenetics as tools to investigate the roles of certain cell types in locomotion. We have relied heavily upon...deliver chemogenetic/optogenetic constructs into our cells of interest. Although they have a small packaging...of serotype (which determines which tissues and cells an AAV can infect) can influence an AAV’s value ... tissue? Location (2): Where in the tissue/which cell type? Location (3): Traveling from the original ...AAV5, AAV6, AAV9 Pancreas AAV8 Photoreceptor Cells AAV2, AAV5, AAV8 RPE (Retinal Pigment Epithelium...-vectors/aav/aav-guide. Where in the tissue/what cell type? In the CNS, for instance, there are marked...
  17. Popular Retroviral Vectors and Their Uses in Scientific Research

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    ... Viruses are intracellular parasites and natural vehicles for genetic information. Therefore they make...make excellent tools for genetic engineering. There are several different viral vectors to choose from,...Virus (MoMLV, MMLV, MuLV, or MLV) or Murine Stem Cell Virus (MSCV) genomes whereas lentiviral vectors ...up of separate envelope and packaging plasmids as well as transfer plasmids. This concept ensures safe ...things) gene delivery, generating pluripotent stem cells, and developing gene therapies for monogenic diseases...vectors, their infectivity is limited to dividing cells. Find tips on using gamma-retroviral vectors in ...are able to transduce dividing and non-dividing cells. More detailed descriptions of the lentiviral elements...
  18. Hot Plasmids February 2024

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    ...yielded editing of 80–90% in human cell lines and primary cells. Although cell entry of a Cas9 ribonucleoprotein...post: Peptide-assisted genome editing for primary cells Monomeric StayGold variants AAV.CAP-Mac for systemic...antibodies Peptide-assisted genome editing for primary cells By Susanna Stroik Even with the advances in CRISPR...CRISPR technology over the past decade, primary cells remain difficult to genetically edit due to toxicity...toxicity from electroporation or poor cellular entry with other transfection methods. The Junwei Shi Lab addressed...Genome Editing (PAGE). They fused the Cas enzyme to cell-penetrating peptides and co-incubate it with an ...including in clinically-relevant lines such as CAR-T cells. Plus, this method is fast! These editing frequencies...
  19. Quick Guide to Near-Infrared Fluorescent Proteins

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    ...Shcherbakova et al., 2016), as well as in four-color imaging (cyan, yellow, red, and near-infrared) (Qian...reporters and biosensors NIR reporters can tell us about cellular events via  fluorescence changes occurring...mammalian cells. dDetermined as effective NIR fluorescence in transiently transfected live HeLa cells with ...Near-Infrared Fluorescent Proteins in Mammalian Cells. Cell Chem Biol 24, 758-766 e753 (2017). Baloban, M...developers and users, BV is present in eukaryotic cells as an intermediate of heme metabolism (Shemetov ...to GFP-like probes by supplying a single gene to cells. Still in bacteria, which do not produce BV, an ... to consider effective brightness of NIR FPs in cells, in addition to their molecular brightness (a product...
  20. The Advances Behind The World's First Personalized CRISPR Treatment

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    ...). The Heroes of CRISPR. Cell, 164(1), 18–28. https://doi.org/10.1016/j.cell.2015.12.041  Musunuru, K....birth. Within a seven-month whirlwind of developing cell and mouse model systems, testing base editing variants...reporting genome editing by CRISPR in mammalian cells appeared in 2013 (Cong et al., 2013; reviewed in...editor (ABE) followed based on similar principles (Gaudelli et al., 2017). These editors did not create double-stranded... The first ABE was about 50% efficient in human cells on average, but its effectiveness varied depending... the chromosomal location, sequence context, and cell type. Multiple labs worked to improve its effectiveness...and more flexible in their target preferences (Gaudelli et al., 2020; Richter et al., 2020).  Five years...
  21. Plasmids 101: Biotinylation

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    ...Immunosorbent Assay) Southern/Northern blotting Cell surface labelling Attaching polypeptides to a substrate Flow...carboxyl groups to organic acids to produce important cellular metabolites. Biotin acts as a carboxyl carrier...chemically. Enzymatic biotinylation occurs naturally in cells and is the process by which biotin is covalently...sequestering biotin from being absorbed. In 1940 Esmond E. Snell was able to purify the protein responsible for binding...the chicken, “Avian”, egg it was purified from. Snell later confirmed that avidin was indeed the culprit... for use in immunohistochemistry and antibody labelling. In these experiments, biotin is added to a primary... Flow cytometry/fluorescence-activated cell sorting (FACS) In situ hybridization Methods for biotinylating...
  22. Hot Plasmids - May 2022

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    ... Mixing the subclones within a single well reduced well-to-well variability, while the readout was able.... Nat Cell Biol. 2022. https://doi.org/10.1038/s41556-021-00836-1 Visual barcodes for live cell clonal...with one visual barcode per cell and up to 200-plex with two barcodes per cell. The researchers validated...long sequence knock-ins Visual barcodes for live cell clonal multiplexing Improving flexibility for ... powerful approach for proteomic mapping in both cell culture and whole organisms (see our 2019 overview...reduced risks of unwanted mutations in mammalian cells. Long sequences traditionally have higher risks ...multiplexing by: Rachel Leeson Multiplexed images in live cells remains a challenge due to multiple factors, including...
  23. Tips for Using FRET in Your Experiments

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    ... N1 Yellow Mammalian Express a gene of interest fused to the N-terminus of Amber Amber C1 Yellow Mammalian... pCEP4YPet-MAMM Yellow Mammalian Expresses mammalian optimized YPet pYPet-His Yellow Bacterial Expresses...(FRET) microscopy imaging of live cell protein localizations. J Cell Biol. 2003 Mar 3;160(5):629-33. ... The student was of course talking about the now well-known FRET, aka Fluorescence (Förster) Resonance...measurement of single molecule interactions in living cells using a microscope. Historically, molecular interactions...suitable for studying interactions within living cells. By coupling fluorophores to proteins, pioneers ...directly detect protein/protein interactions in living cells. Since then FRET has also been used to measure conformational...
  24. Selecting Your Plasmid Purification Kit

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    ... For most kits, the steps for lysing cells and removing cellular debris look very similar. However, keep... Yes —beads, columns, plates, buffers 96-well plates, 8-well kit, automation-friendly Not mentioned Endotoxin-free...relative term — even armed with the highest-competency cells you will still struggle to get transformants if ...quantity) – Depending on the experiment, mammalian cell transfections can require quite large amounts of...your plasmid; separate plasmid DNA from unwanted cellular “debris”; and then clean-up the plasmid DNA (Figure...your bacteria to release the plasmid, separate the cell debris from the plasmid, and then clean-up the plasmid...and column-based DNA purification methods perform well in terms of quality and yield. Bead-based purifications...
  25. Viral Vectors 101: An Introduction to AAV

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    ...Time to expression AAVs have to infect cells, hijack host cell machinery, and synthesize a second strand...that can be used to express genes of interest in cell and animal models. AAVs are non-pathogenic, do not...be specifically targeted to a number of different cell types even when systemically administered in an ...ranging from transient gene expression in a particular cell type to CRISPR genome editing, optogenetics, and...application of AAV is delivery of genetic cargo to a host cell. In order to make room for a gene of interest, AAVs...Serotype refers to the type of capsid (outer protein shell) used to package an rAAV vector; these capsids allow...allow the virus to infect (or not infect) different cell types with some specificity. There are a lot of ...
  26. Mapping the 4D nucleome with CRISPR/Cas9

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    ...be applicable to studies of cell cycle progression, epigenetics and cellular reactions to external stimuli...Weissman JS, Qi LS, Huang B. Cell. 2013 Dec 19;155(7):1479-91. doi: 10.1016/j.cell.2013.12.001. Pubmed. Find...LS, Weissman JS, Vale RD. Cell. 2014 Oct 23;159(3):635-46. doi: 10.1016/j.cell.2014.09.039. Epub 2014 Oct...labeled Cas9 to label multiple genomic loci in live cells. While other systems can be used to label loci, ...CRISPR/Cas9’s ease of use and ability to label live cells make this system truly advantageous. This new technique...nuclear organization varies across the life of a cell, or how organization may be altered in disease states...dead Cas9 (dCas9) has many applications, the most well-known being transcriptional activation/repression...
  27. Hot Plasmids May 2018 - Optogenetics, Decaffeination, Biosensors, and Fluorescent Protein Tools

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    ...illumination of neighboring cells evokes action potentials (APs) in patched cells expressing wild type CoChR...techniques for live-cell imaging of the dynamic changes in biochemical activity within the cell. Their Fluorescence...distribution of clusters without accumulation in subcellular compartments such as nuclear speckles. Furthermore...OptoSTIM1), caused two-fold faster changes in intracellular Ca2+ levels than the original version containing...CRY2clust should prove a useful tool to further probe cellular function. The CRY2clust Plasmid can be found here...28646204. soCoChR: A novel opsin that enables single-cell optogenetics Article contributed by Meghan Rego ...wild type CoChR, soCoChR localizes primarily to the cell body with very little signal detected along the ...
  28. Viral Vectors 101: Chemogenetics

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    ...neuroscience where specific tissues, cell types, or even subcellular regions of a neuron need to be targeted...pathways, giving rise to the same cellular responses. The cellular response set off by a DREADD depends ...disease, neuroscientists need to be able to probe cells and circuits without disrupting normal brain function...it provides a noninvasive method for manipulating cell activity, especially neuronal firing. What is chemogenetics...drugs. Once activated, chemogenetic receptors hijack cell signaling pathways and can lead to such responses...requires successfully introducing receptors to target cells. Targeted and specific delivery becomes especially...ability of agonists to successfully reach target cells while resulting in minimal off target effects. For...
  29. Hot Biosensors 2022: Year-End Roundup

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    ...two-photon microscopy. Cell. 2022 Aug 16. pii: S0092-8674(22)00916-3. doi: 10.1016/j.cell.2022.07.013 pYtags...Calcium Indicator. Front Cell Dev Biol. 2022 Jun 29;10:880107. doi: 10.3389/fcell.2022.880107. KRaION potassium...Stop and smell the flowers - or rather, the lactate! The latest biosensor from Gary Yellen’s lab is LiLac...fluorescence unit fused with TRansmembrane region-to-IntrAcellular loop linkers” (MTRIA for short), where a fluorescent...inserting a circularly-permuted GFP into an intracellular loop of various G-protein-coupled receptors....fluorescent sensor for real-time measurement of extracellular oxytocin dynamics in the brain. Nat Methods....sensor relies on a change in localization to the cell membrane and not a direct change in the fluorescent...
  30. Antibodies 101: Single Chain Fragment Variables (scFvs)

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    ...scFvs and T cell receptors and are expressed on T cells to make CAR T cells. The extracellular scFv portion...Bispecific T-cell engagers (BiTE®s), bind CD3 on T cells and a tumor-specific antigen, it brings T cells to a ...recognizes an antigen of interest while the intracellular T cell receptor portion of the CAR facilitates ...scFv part of the receptor can activate T cells to kill cancer cells. scFv’s small size also allows for their... display libraries screen antibody genes from B cells of immunized animals, but it's possible to avoid...also allows for screening scFv generated from the B cell antibody genes from diseased or vaccinated humans...produce scFvs in mammalian, yeast, plant, and insect cells, they are most often expressed from a plasmid in...
Showing: 331 - 360 of 1027 results