Technical library

Normal cells have a finite life span and therefore eventually stop growing and become senescent. In addition a cease in proliferation or cell death can be induced by other factors. For more details check the trouble shooting guide below.

Slow growth after subculture can be caused by over-trypsinization or other suboptimal culture conditions. Please see attached trouble shooting guide for possible reasons.

Several different methods for the detection of mycoplasmas have been described like e.g. cultures on agar in liquid or semi-solid media staining with DAPI mycoplasma-specific antibodies biochemical methods and PCR-based assays. PCR-based detection is very sensitive detects all mycoplasma species that occur in cell cultures and is completed within 3-5 hours.

At PromoCell; we get the umbilical cords from our tissue suppliers with no addition of buffers or media. This method prevents the microorganisms from being washed into the blood vessels. Before we start the cell preparation; the umbilical cord is also cut on both ends with a sterile scalpel to provide sterile intersections in addition to the sterile lumen. This method allows us to isolate sterile endothelial cells from umbilical vein and to plate them in antibiotics-free culture media.

Typical cell densities are between 32.000 - 40.000 cells/cm² (approx. 800.000 - 1 million cells per T25-flask).

For mineralization assays; HOB are cultured in Osteoblast Mineralization Medium (C-27020). Mineralization can be detected after approximately 3 weeks by incorporation of Ca-45; or it can be visualized by von Kossa or Alizarin Red staining for calcium.

If you purchase a proliferating culture of human osteoblasts (C-12760); there will be > 500;000 cells in the TC-flask. Once the culture is subconfluent; you will count between 750;000 - 1.1 million cells/T25 (depending on the cell lot).

Normal osteoblasts similar to other non-transformed cell types can be expanded in vitro to a certain extent before they are used for experiments. Nonetheless HOB are generally used at low passages (up to P4) in most labs.

Our Osteoblast Growth Medium (C-27001) consists of the Basal Medium supplemented with 10% (v/v) FCS but with no recombinant growth factors. The medium primarily supports the proliferative capacity of normal human osteoblasts. It does not contain osteogenic factors (like dexamethasone and beta-glycerophosphate) that promote differentiation as many users test their own chemical compounds (growth factors hormones) or examine the effects of physical strain or sheer stress on the differentiated functions. The Osteoblast Growth Medium is well-suited as the basis for these applications and can be supplemented with further growth factors if necessary. To specifically induce mineralization PromoCell supply Osteoblast Mineralization Medium (C-27020).

Induction of differentiation: - Grow the cells in Preadipocyte Growth Medium (C-27410) until they reach complete confluence; this roughly takes 1 week. Change medium 2-3x per week. - Aspirate the Growth Medium; add Preadipocyte Differentiation Medium (C-27436) for 72 h - Aspirate the Differentiation Medium; add Adipocyte Nutrition Medium (C-27438). The cells will now start to accumulate droplets of lipids which can be visualized under the microscope. The process usually takes 1-2 weeks. Change medium 2-3x per week. It is possible to maintain the differentiated adipocytes in Nutrition Medium for up to 4 weeks. However; the cells tend to lyse and detach after about 3 weeks. Please note: We recommend to perform differentiation experiments at population doubling numbers lower than 4-5 (a maximum of 1 passage after thawing) in order to obtain a high differentiation level of the culture.

Yes our Skeletal Muscle Cell Differentiation Medium is completely defined. The SupplementMix (C-39366) consists of recombinant human insulin.

PromoCell Fibroblast Growth Medium is serum-free and therefore not subjected to the lot-to-lot variations observed with DMEM/10% FCS. Our Fibroblast Growth Medium therefore allows for much more standardized cell culture conditions.