Technical library

Upon arrival; you can either defrost the cells immediately and seed them in a TC vessel or store the vial in liquid nitrogen until needed. It is possible to re-freeze normal human cells but PromoCell does not recommend it; because each freezing cycle leads to a loss in proliferation potential. If you want to freeze them; please use Cryo-SFM (C-29910) which is a serum-free freezing medium that prevents the possibility that any serum is introduced into your serum-free cell culture system. It is also recommended to freeze the cells at an early passage.

We guarantee 15 population doublings for our NHEM. In terms of passages this corresponds to approx. 6-8 subcultivations. 

We can however not guarantee that the activity of all melanocyte genes remains unchanged during this time. Primary cells do gradually change their phenotype in vitro. Therefore, it is recommended to use the cells for the important experiments at low passages.

After isolation and purification of our primary human melanocytes, the cells are checked during quality control whether they show a typical morphology and whether they express the marker Mel-5. Mel-5 is a 75 kDa glycoprotein usually expressed by normal melanocytes. Our Melanocyte Growth Medium (C-24010) has been developed to promote melanocyte growth in vitro. It does not however, completely block the growth of other cells (such as: NHEK or NHDF). 

Therefore, it is important to have a pure melanocyte culture from the very beginning. 

In contrast, the Melanocyte Growth Medium M3 (C-24310) is much more selective and represses the growth of contaminating cells much better.

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.

PromoCell Chondrocytes can be expanded in normal monolayer culture using our Chondrocyte Growth Medium (C-27101). The Medium consists of an optimized formulation and is supplemented with 10 % FCS. De-differentiation of chondrocytes is a known phenomenon observed during in vitro-culture after a period of approx. 2 weeks; but in vitro-culture is needed to expand the cells. Once a suitable cell number is obtained; the monolayer system can be changed to a more complex 3-D system either by culturing the cells on substrates like alginate beads; gels; or degradable polymer scaffolds or by using 3-D spheroid culture. Using appropriate conditions; re-differentiation is triggered and the cells start producing cartilage-specific ECM again. PromoCell does not supply a special culture system but we use 3-D spheroid culture and Alcian Blue staining to characterize our chondrocytes during quality control. The protocol is very similar to the one we use for chondrogenic differentiation of MSC.

Mature chondrocytes from articular cartilage are postmitotic producers of extracellular matrix components like collagen types II IX and XI and proteoglycans. Upon release from the tissue of origin and seeding in monolayer culture cells re-enter the cell cycle and proliferate. After a period of approx. 1-3 weeks they will gradually start dedifferentiation and will adopt a fibroblastic phenotype. Dedifferentiation can be detected by decreased collagen type II or increased collagen type I expression as well as by the appearence of the fibroblast marker Thy-1/CD90. Re-differentiation can be induced by changing from conventional monolayer culture to a 3-D culture system.

All our chondrocytes (C-12710) are isolated either from knee joint or femoral head. If you need chondrocytes specifically from either localization please contact our Technical Customer Service before placing your order. They will send you the available lot numbers from the localization that you are looking for.

We get 5-8 new lots of adult MNC (C-12907) every month (> 15 vials each). Cord blood MNC (C-12901) are smaller lots (5-10 vials); we get 2-4 new lots every month.

Our MNC lots are checked for the rate of lymphocytes monocytes and granulocytes w/o staining by FSC/SSC using a flow cytometer. A sample plot is attached. For our purified CD14⁺ monocytes we additionally perform a CD14⁺ staining.

The cells will die. Hematopoietic Progenitor Cell Expansion Medium XF always must be supplemented with Cytokine Mix E or an appropriate cocktail of cytokines.

The study of angiogenesis has been significantly advanced by the ability to culture endothelial cells in vitro. Initially large vessel ECs such as those isolated from the human umbilical vein (HUVEC) were used for these studies but increasingly it has been recognized that microvascular endothelial cells are a more appropriate model since angiogenesis involves microvessels rather than large vessel ECs.

PromoCell Normal Human Cells should be cultured in the appropriate medium at 37°C and 5% CO₂ in a humidified atmosphere. Please note: If using cell culture flasks w/o filter cap; unscrew the cap by half a turn to allow sufficient ventilation.