Cell culture models using 2D substrates have provided important conceptual advances in understanding the biology of cells. However, cells grown on flat 2D surfaces can differ substantially from physiological environments. Animal models provide a useful tool to study biology in a physiologically relevant environment. However, animals models are expensive, time-consuming, use a significant amount of test material, and do not always provide a useful extrapolation to humans. In vitro 3D cell culture models bridge the gap between the two, allowing the study of human cells in a physiologically-relevant environment with the convenience and speed of an in vitro model. [Read more…]
Human induced pluripotent stem (iPS) cells and cells differentiated from iPS cells have widely been used for in vivo models human disease progression. Jason Meyer, of Indiana University Purdue University Indianapolis, uses iPS cell-derived models to study retinogenesis and retinal disease. Two recent papers from his lab highlight the benefits of using Stemgent’s RNA reprogramming technology to enable robust differentiation of iPS cells to the retinal lineage (1, 2). RNA reprogramming technology was chosen in order for these studies to ensure that no vestiges of the reprogramming vectors were retained by the cells or integrated into the genome.
The introduction of transgenes into stem cells has shown to be a valuable experimental technique for studying stem cell biology. Transfecting stem cells without inhibiting cell viability and cell growth has shown to be difficult. DNA-In® Stem Transfection Reagent offers a simple, robust and reproducible method for delivering DNA into a wide range of stem cells, including neural stem cells. Formulated and optimized specifically for embryonic and adult stem cells, DNA-In® Stem is a new-generation transfection reagent that enables high efficiency transfection while maintaining maximum cell viability and cell growth.
In this post, I invite you to discover the benefits of using DNA-In® Stem Transfection Reagent vs. other reagents. A lot of pictures and graphs rather than long descriptions! Last but not least, DNA-In® Stem Transfection Reagent is less expensive compared to Lipofectamine reagents… [Read more…]
Donor-derived lymphocytes attack a patient’s cancer — but may attack the patient as well. Donor chimeric antigen receptor (CAR) T cells, on the other hand, brought remissions without this troubling complication.
CAR T cells continue to make waves: At the latest annual meeting of the American Association for the Advancement of Science, it was announced that CAR T cells, in which T cells from a patient are genetically reprogrammed to target cancer cells, removed all traces of cancer in the bone marrow of 27 out of 29 acute lymphoblastic leukemia patients. Nineteen of 30 individuals with non-Hodgkin lymphoma also responded in the form of partial or complete responses. The cumulative successes found in CAR T cell studies have labeled them “extraordinary.” [Read more…]
NADPH is a critical cofactor supporting numerous biochemical reactions. In ADME-Tox studies, NAD(P)H regeneration is strongly recommended when using drug metabolizing enzymes (ex. Cytochrome P450 (CYP), Flavin-containing MonoOxygenases (FMO)), Recombinant CYPs (incl. bactosomes) or cellular fractions (Microsomes, S9). Currently, the most simple and cost-effective way to regenerate the NAD(P)H in situ and enzymatically is to use the commercially-available RapidStart™ NADPH Regenerating System (Xenotech-Sekisui). [Read more…]
The inadequacy of animal models to predict human biology in the drug development process is becoming increasingly clear, due to species differences in uptake and metabolism at both cellular and organ levels.
As a result, there is a need for more human model systems to be incorporated earlier in research and development.
Innovative concepts such as “body on a chip” have been introduced, but the complexity and miniaturization of many of the formats has limited applicability on a commercial scale.
SciKon is developing tools that better recapitulate biological systems in bench-top cell culture formats, which are amenable to mass manufacturing (introduced recently in the post Cell Signaling isn’t static…your cell culture shouldn’t be either!). [Read more…]
Lipotransfers are ideal for restorative surgery, but retention is a problem. In a recent study, PRP grade concentrated platelets were used for a study examining how platelet-rich plasma helps to enhance fat graft survival.
In this age of crash diets and liposuction, it might sound surprising that some people receive fat transplants. But seriously, fat grafting is widely used and valued as a feasible method for addressing moderate defects caused by injuries, surgical removal of tumours, and congenital deficiencies. Fat grafting is safe and has the look and feel of normal soft tissue. However, long-term volume retention is suboptimal (30-70%), often requiring multiple surgeries. [Read more…]
ATRA is a well known for its ability to regulate cell differentiation. However, retinoids are excellent chromophores and efficiently absorb light and isomerise. This is not necessarily a feature required of cell culture reagents, where consistency and reliability of a product is important for robust reproducible results.
To address this issue, Reinnervate have recently developed ec23® as a pan-RAR receptor agonist that is stable, but maintains the same biological activity as ATRA. [Read more…]
Induced-pluripotent stem cells (iPSC) are produced from a variety of source tissues including fibroblasts, epithelial progenitor cells, peripheral blood mononucleocytes (PBMC), and others. For Human iPSC, the pluripotency state is sometimes referred to as the “primed” state. Among iPSC lines, heterogeneity has been shown to exist in proliferation and the capacity to differentiate. This can cause issues in data interpretation or even limit the utility of Human iPSC in some disease cell models for basic research or drug discovery.
Recent publications have shown that Human iPSC, when cultured under special conditions, can be transitioned to what may be a more primitive form perhaps similar to cells in the pre-implantation state of a developing embryo. This state is referred to as the “naïve” state. In mouse and rabbit iPSC systems, naïve state cells have been shown to increase the efficiency and reproducibility (less bias) of terminal differentiation, including giving rise to some terminally differentiated cell types that display greater maturity. Thanks to this evidence (in other species), the accelerated growth characteristics of naïve cells, and other attributes linked to pluripotency, there is worldwide a rapidly growing interest in the Human stem cell research community. [Read more…]
Complex cell culture systems are emerging as key tools to improve physiological relevance of in vitro assay systems. There have been two main ways by which investigators attempt to improve mimicking of physiological conditions in cell and tissue culture. The first is to develop more complex model systems where two or more cell types are co-cultured in a 3D structure either separated by membranes or in spheroids . The second is to incorporate fluidic-flow where the motion of the media itself has been shown to improve metabolic function and lifespan [2,3].
Despite the success of better recapitulating function at the cellular level using these two methods, neither of these approaches addresses the issue of the non-linear nature of the drug or toxicant exposure as is observed in an in vivo system . As a result, the capacity to accurately predict in vivo pharmacokinetics and pharmacodynamics still falls short reaching at best 60-70% accuracy [5,6].
So what’s new in this area? We were interested to discover the following system, which we think will be of interest to many researchers. Let’s take a closer look at the characteristics and how it can be used. [Read more…]