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FEATURED NEW PRODUCTS
what they are
CellLight® reagents are fluorescent protein–signal peptide fusions that permit accurate and specific targeting to cellular structures, including lysosomes, for live-cell imaging applications, or for fixed-cell analyses following formaldehyde-based fixation.
what they offer
how they work
Cellular labeling with CellLight® reagents employs BacMam technology, which uses a modified insect cell baculovirus coupled with a mammalian promoter as a vehicle to efficiently deliver and express genes in mammalian cells. The inability of baculoviruses to replicate in mammalian cells renders them safe as research reagents and provides a transient, footprint-free method to label cells. Unlike expression vectors, BacMam reagents enable titratable and reproducible expression and offer high cotransduction efficiency, enabling multiple BacMam reagents to be used in the same cell.
Monitor Influenza Strains for Resistance to Neuraminidase Inhibitors — Applied Biosystems® NA-XTD™ and NA-Fluor™ Influenza Neuraminidase Assay Kits
what it is
Monitor influenza strains for resistance to neuraminidase inhibitors with the NA-XTD™ or NA-Fluor™ Influenza Neuramindase Assay Kits. These assay kits provide chemiluminescent or fluorescent detection reagents with complete assay protocols for quantitating the sensitivity of influenza virus isolates to neuraminidase inhibitors.
what it offers
how it works
The NA-XTD™ Influenza Neuraminidase Assay Kit yields a long-lasting chemiluminescent readout, and the NA-Fluor™ Influenza Neuraminidase Assay Kit is a fluorescent assay based on the traditional MUNANA substrate, comparable to published NISN protocols. The kits enable detection of low virus concentrations in viral isolates or cell-based samples for easy screening of new neuraminidase inhibitors. The assays detect seasonal influenzas, including human types A and B and A/H1N1 pandemic, and avian, equine, and porcine strains.
what it is
Chemokines are a family of small cytokines, or proteins secreted by cells. Some chemokines are considered proinflammatory and can be induced during an immune response to promote cells of the immune system to a site of infection, while others are considered homeostatic and are involved in controlling the migration of cells during normal processes of tissue maintenance or development.
what it offers
how it works
The Human Chemokine II 5-Plex Panel is a multiplex bead immunoassay designed to simultaneously determine the protein concentrations of human I-309/CCL1, MDC/CCL22, MIP-3α/CCL20, TARC/CCL17, and ENA-78 in serum, plasma, or tissue culture supernatant. The assay is a solid-phase sandwich immunoassay designed to be analyzed with a Luminex® 100™/200™ or FlexMAP 3D® instrument. The assay may be run alone or in combination with other Invitrogen™ chemokine panels.
|CXCL5/ENA-78 ||Epithelial Neutrophil Activating Peptide ||Produced by IL-1– or TNF-alpha–stimulated epithelial cells and fibroblasts. Attracts and activates neutrophils. Elevated in synovial fluid of RA. Elevated in Crohn’s disease, ulcerative colitis, acute appendicitis, acute pancreatitis. |
|CCL1/I-309 ||(I-309 refers to a cDNA clone) ||Produced by T lymphocytes upon activation. A monocyte chemoattractant. I-309 has been implicated in angiogenesis and asthma. Its biological activity is blocked by MC148R, an open reading frame found in the genomes of molluscum contagiosum virus (MCV) type 1 and type 2. Localizes in atherosclerotic plaques. |
|CCL22/MDC ||Macrophage-Derived Chemokine ||Produced by macrophages and monocyte-derived dendritic cells (but not monocytes). Upregulated by Th2 cytokines such as IL-4 and IL-13. Plays a role in the recruitment of Th2 cells by antigen-presenting cells; a chemoattractant for monocyte-derived dendritic cells, activated NK cells, and activated T cells. Found in advanced atherosclerotic plaques. |
|CCL20/MIP-3α||Macrophage Inflammatory Protein 3 alpha (aka LARC and Exodus) ||Produced by lymphocytes, lymph nodes, liver, and appendix. Upregulated by LPS and proinflammatory cytokines. Plays a role in the trafficking of memory T cells, B cells, and dendritic cells. Shown to have antibacterial properties with E. coli, S. aureus, P. aeruginosa, and others. |
|CCL17/TARC||Thymus and Activation-Regulated Chemokine||Constitutively expressed by thymus. Transiently upregulated in PHA-stimulated PBMCs. Plays a role in the trafficking of Th2 cells. TARC is produced by Reed-Sternberg cells of Hodgkin’s lymphoma, and thus is a biomarker for this disease. Also implicated in asthma.|
|Chemokine Human 10-Plex Panel ||Eotaxin, GRO-α, IP-10, MCP-1, MCP-2, MCP-3, MIG, MIP-1α, MIP-1β, RANTES, and Buffer Kit||100 tests ||LHC6001|
|Chemokine Human 5-Plex Panel ||Eotaxin, MCP-1, MIP-1α, MIP-1β, RANTES, and Buffer Kit||100 tests ||LHC0005|
|Chemokine II Human 5-Plex Panel ||I-309/CCL1, MDC/CCL22, MIP-3α/CCL20, TARC/CCL17, ENA-78, and Buffer Kit||100 tests ||LHC0012|
|Traditional gene expression profiling, based on the quantitation of total mRNA, is biased to detect changes in short-lived transcripts, because the slow turnover of long-lived transcripts can obscure short-term changes in their synthesis. Analysis of newly transcribed (nascent) RNA provides information that cannot be obtained using traditional total RNA preparations. The new Click-iT® Nascent RNA Capture Kit makes it simple to partition newly transcribed RNA from preexisting RNA, and enhances the resolution of gene expression analysis compared to methods using total RNA. |
The new Click-iT® Nascent RNA Capture Kit is based on metabolic labeling of nascent RNA with the modified nucleoside 5-ethynyl uridine (EU), and subsequent purification of labeled RNA using click chemistry–based capture. The procedure is simple—EU ribonucleotide homologs containing an alkyne reactive group are fed to cells or tissue, and once incorporated, cells are lysed and the RNA is isolated for transcriptome analysis. A unique benefit of Click-iT® EU is the small size of the alkyne tag (MW ~25), which enables its efficient incorporation by RNA polymerases without any apparent changes to the global transcriptome. A biotin azide is then "clicked on", and streptavidin magnetic beads are used to capture the newly synthesized pool of RNA. The captured RNAs are then amplified and the resultant cDNAs are used in any number of post-capture methodologies.
The figure to the right illustrates high-resolution gene expression analysis facilitated using the Click-iT® Nascent RNA Capture Kit method. The bars on the graph represent the change in relative gene expression (ΔΔCt) in response to an experimental treatment. For six of the nine transcripts analyzed, the fold difference in Ct values is greatly enhanced when nascent RNA was evaluated rather than total RNA.
High-resolution gene expression analysis with the Click-iT® Nascent RNA Capture Kit. Relative expression (∆Ct) of the indicated genes was compared with and without a treatment thought to affect apoptosis (∆∆Ct). For many transcripts, the change in relative gene expression observed was much more dramatic when nascent RNA was used for the analysis rather than total RNA.
Schermelleh L, Heintzmann R, Leonhardt H (2010) J Cell Biol 190(2):165–175.
In attempting to visualize biological structures, life scientists through the ages have had to strike a balance between experimental requirements and technical performance. Cell biology has, to date, been limited by the optical resolution of light microscopy, but some super-resolution technologies are making headway. In a recent review of these technologies, Schermelleh and colleagues summarized both near-field and far-field methods. One method in particular—structured illumination microscopy (SIM)—is particularly amenable to cell biology applications because it can utilize standard dyes and staining protocols and still deliver simultaneous imaging of multiple cellular structures with optical sectioning in three dimensions (3D-SIM). The authors also note that there are several challenges still remaining, including the development of methods for super-resolution imaging that do not affect the physiology or viability of live cells, and those that are effective with thick biological specimens.
- Explore the Molecular Probes® Basic Imaging Toolbox
| ||Imaging stem cell–derived cardiomyocytes with CellLight® reagents. Cardiomyocytes were incubated overnight with CellLight® Actin-GFP in complete medium. The following day, cells were imaged using standard DAP/FITC/TRITC filters. The striations of actin filaments characteristic of muscle cells are clearly evident.|
Alkaline Phosphatase Detection in Pluripotent Stem Cells
Pluripotent stem cells such as embryonic stem cells and induced pluripotent stem cells can self-renew and differentiate into cell types of all three germ layers. These cells are identified and characterized based on the expression of specific surface antigens, pluripotency-specific transcription factors, and high levels of alkaline phosphatase. The ELF® 97 Endogenous Phosphatase Detection Kit provides a fast, easy method to detect phosphatase activity. Upon hydrolysis, the ELF® 97 phosphatase substrate produces a bright and photostable yellow-green fluorescent precipitate at the site of enzymatic activity. This fluorescent precipitate has several unique spectral characteristics, including an extremely large Stokes shift (180 nm), that make it easily distinguishable from endogenous fluorescence.
When ELF® 97 substrate is applied to pluripotent cells, undifferentiated colonies fluoresce green while differentiated cells and feeder cells remain unstained. The signal can be easily observed on a conventional fluorescence microscope using a FITC filter. This differential staining pattern enables a rapid method to identify pluripotent stem cells, especially during the generation of induced pluripotent stem cells. The robust signal can be easily observed typically within 30 minutes of application, with or without cell fixation. ELF® 97 can be used in combination with other pluripotent stem cell detection methods such as antibody staining.
- View Invitrogen™ Stem Cell Protocols
|Alkaline Phosphatase Detection in Pluripotent Stem Cells. H9 human embryonic stem cells were cultured on a feeder layer of irradiated murine embryonic fibroblasts in hESC medium containing 20% KSR and 4 ng/mL bFGF. Cells were stained with the ELF® 97 Endogenous Phosphatase Detection Kit (left) or the ELF® 97 Endogenous Phosphatase Detection Kit in combination with detection of TRA-1-60 (right). Images were collected on an Axiovert fluorescence microscope using a blue filter for DAPI, green filter for ELF® 97, and red filter for Alexa Fluor® 594–labeled secondary antibody against SSEA4, at 10x magnification.|
|ELF® 97 Endogenous Phosphatase Detection Kit||1 kit||E6601|
Our Complete Flow Cytometry Portfolio, Right on Your Desktop
To make it easier to find Invitrogen™ flow cytometry reagents from your computer, we've created an electronic flow cytometry catalog that you can download and view at your convenience. The catalog contains:
- Hyperlinks to every individual product page
- Hundreds of fluorescent conjugated primary antibodies
- Molecular Probes® functional reagents for cell cycle, apoptosis, dead cell discrimination, and more
- Extensive references on how to optimize the use of our reagents
|Molecular Probes® Basic Imaging Toolbox|
We’ve recently launched a basic imaging website that makes it easy to find all the reagents required for an imaging protocol. From antibodies and fluorescent dyes to antifade reagents and signal enhancers, this page directs you to the tools you need for easy and efficient experimental design.
Molecular Probes® The Handbook
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