siRNA / RNAi /miRNA transfection Human Cells Cal 27 cells

Stem cells have the unique ability to self-renew or differentiate themselves into various cell types in response to appropriate signals. These cells are especially important for tissue repair, regeneration, replacement, or in the case of hematopoietic stem cells (HSCs) to differentiate into various myeloid populations. Appropriate signals refer to the growth factor supplements or cytokines that mediate differentiation of various stem cells into the required differentiated form. For instance, HSCs can be differentiated into dendritic cells (with IL-4 and GM-CSF), macrophages (with m-CSF) and MDSCs (with IL-6 and GM-CSF). Human pluripotent stem cells (hPSCs) and induced pluripotent stem cells (iPSCs) can be first cultured in neural differentiation media (GSK3𝛃-i, TGF𝛃-i, AMPK-i, hLIF) to form neural rosettes, which can be differentiated into neural or glial progenitors (finally differentiated into oligodendrocytes). Neural progenitors can be finally differentiated into glutaminergic (dibytyryl cAMP, ascorbic acid) and dopaminergic (SHH, FGF-8, BDNF, GDNF, TGF-𝛃3) neurons. Thus, it is important to first identify the self-renewing cell line: its source and its final differentiation state, followed by the supplements and cytokines required for the differentiation, and final use. Timelines are another thing that is considered. For instance, it takes 7-10 days to form neural rosettes from iPSCs and 3 days to differentiate neural progenitors to neurons. Finally, the stability for stem cell culture media varies. It is advised to make fresh media every time when differentiating HSCs to myeloid populations, whereas neural differentiation media may remain stable for two weeks when stored in dark between 2-8C.

Get tips on using Attractene Transfection Reagent to perform DNA transfection Mammalian cells - Immortalized cell lines OVCAR-3

Get tips on using SMARTpool: ON-TARGETplus Hipk2 siRNA to perform siRNA / miRNA gene silencing Mouse - Glomerular mesangial cells HIPK2 Polymer / Lipid delivery

DNA microarrays enable researchers to monitor the expression of thousands of genes simultaneously. However, the sensitivity, accuracy, specificity, and reproducibility are major challenges for this technology. Cross-hybridization, combination with splice variants, is a prime source for the discrepancies in differential gene expression calls among various microarray platforms. Removing (either from production or downstream bioinformatic analysis) and/or redesigning the microarray probes prone to cross-hybridization is a reasonable strategy to increase the hybridization specificity and hence, the accuracy of the microarray measurements.

TUNEL assay is the cell death detection method where the biochemical marker of apoptosis is DNA fragmentation. The assay involves the microscopical detection of generated DNA fragments with free 3'-hydroxyl residues. in apoptotic cells using enzyme terminal deoxynucleotidyl transferase (TdT) which adds biotinylated nucleotides at the site of DNA breaks. Major challenges of this method involve proper access of the enzyme which could be hampered by poor permeabilization and/or excessive fixation with cross-linking fixative (common with archival tissue). This issue can be resolved by optimizing the incubation time with Proteinase K or CytoninTM.

Get tips on using mirVana™ miRNA Isolation Kit, with phenol to perform RNA isolation / purification Cells - primary human airway epithelial cells

Get tips on using mirVana™ miRNA Isolation Kit, with phenol to perform RNA isolation / purification Cells - primary human aortic endothelial cells

TUNEL assay is the cell death detection method where the biochemical marker of apoptosis is DNA fragmentation. The assay involves the microscopical detection of generated DNA fragments with free 3'-hydroxyl residues. in apoptotic cells using enzyme terminal deoxynucleotidyl transferase (TdT) which adds biotinylated nucleotides at the site of DNA breaks. Major challenges of this method involve proper access of the enzyme which could be hampered by poor permeabilization and/or excessive fixation with cross-linking fixative (common with archival tissue). This issue can be resolved by optimizing the incubation time with Proteinase K or CytoninTM.

The process of RNA extraction from bacteria, in general, involves an RNA-protective, effective lysis of bacterial cell wall (which may pose difficulties). EDTA promotes loss of outer membrane to provide lysozyme with access to peptidoglycan. Another common method for cell wall lysis is mechanical disruption using a homogenizer (applied for gram-positive bacteria and some strains of gram-negative bacteria). Following lysis, it is necessary to disrupt protein-nucleic acid interactions, which can be achieved by adding sodium dodecyl sulfate (SDS). Next step involves using phenol-chloroform-isoamyl alcohol extraction, where RNA can be obtained from the bottom organic phase, the top phase consists of DNA and the interphase contains proteins. Isoamyl alcohol is an inert and optional addition to this mixture and is added as an anti-foaming reagent to reduce the interphase. Following RNA extraction, the samples should be checked for its quality by gel electrophoresis (23S and 16S rRNAs and 5s rRNA and tRNA bands) or UV spectrophotometric or fluorescence methods.