Technical library

The PromoCell Basal Media must be stored between 4-8°C and should not be frozen, as this can lead to precipitations. The same is true after addition of the supplements: the complete medium has to be kept at 4-8°C. If you prefer to make up smaller volumes of complete medium, you can aliquot the Supplement Mix and refreeze those aliquots at -20°C until use. This way you can extend the period in which you can use the supplemented media.

The majority of our skin tissue donors are caucasians. But occasionally we also get skin biopsies from asian and black donors.

Please contact our Scientific Support if you need cells from a particular phototype or origin. They will check our inventory and send you a list of available cell lots.

We recommend a seeding density for chondrocytes between 10,000 and 20,000 cells/cm². This means that a subconfluent T25-flask with approx. 900,000 cells/T25 flask (36,000 cells/cm² ) may be either split into 3 new T25 or seeded in one T75 flask or in one 100 mm petri dish. We do not recommend a specific type or brand for the culture of HCH.

The Chondrocyte Growth Medium SupplementMix consists of Fetal Calf Serum (final concentration 10 % v/v) which has specifically been tested for the culture of primary chondrocytes. FCS contains a variety of different growth factors, which are however, not analyzed in more detail. There are no further growth factors added to the SupplementMix.

The optimal calcium concentration for both proliferation and differentiation of keratinocytes depends on the species and also on the media formulation. To keep primary human keratinocytes in the proliferative status, concentrations between 0.03 and 0.15 mM (PromoCell Keratinocyte Growth Medium 2: 0.06 mM) are generally used. Increasing the calcium above 1 mM will induce terminal differentiation and lead to the loss of proliferative activity.

No, we don't perform CD90 immunomagnetic separation with our pericytes. We can however exclude fibroblast contamination as follows: 1) The presence of fibroblasts in our pericyte cultures would be detectable shortly after cell isolation, as pericytes need up to 2 weeks before they start proliferating. Fibroblasts on the other hand would proliferate immediately and overgrow the culture. 2) Characterization of the isolated pericytes during QC includes flow cytometry of CD146. Pericytes express CD146 whereas placental fibroblasts don't.

CD146 (MUC18) is a surface marker, expressed on pericytes, MSCs, and endothelial cells from large vessels (but not microvascular endothelial cells). In combination with CD34 (a marker for endothelial and hematopoietic cells), pericytes can be characterized by FACS analysis as CD146⁺/CD34^-. The absence of CD34 expression makes sure that the cells are not of hematopoietic/endothelial origin. Further markers that have been described for pericytes are NG2, CD90, alpha-SMA, and PDGFR-beta.

Our Human Renal Cortical Epithelial Cells (C-12660) are isolated from the cortex of the human kidney. The renal cortex is the outer portion of the kidney. It contains the renal corpuscles, the proximal and distal convoluted tubules, and the cortical collecting ducts.

Our HPF (C-12360) are isolated from peripheral lung tissue.

Recommended procedure: - Thaw the vial according to our protocol - Seed one part of the cells (5,000 cells/cm²) directly into multiwell plates for subsequent differentiation induction; grow in Preadipocyte Growth Medium until they reach 100% confluency, then induce differentiation according to the recommended protocol - Seed the other part (5,000 cells/cm²) into a TC dish and expand them in Preadipocyte Growth Medium; trypsinize at subconfluence; if necessary divide the cell suspension again into two parts and use one part for differentiation tests (see above), the other part to continue the culture of undifferentiated HWP. - Differentiation capacity may decline after 1-2 passages in vitro, therefore best perform your differentiation tests at early passages. HWP at higher passages can still be used for studies that require undifferentiated HWP (e.g. proliferation assays).