Technical library

The following criteria are applied for blood donations: a) Donors with light infection like a cold or cough are excluded for one week b) Donors with infections with a temperature above 37.9°C and/ or antibiotics therapy are excluded for 4 weeks c) Blood pressure: exclusion only if systolic blood pressure is < 100 mm Hg or > 180 mm Hg or if diastolic blood pressure is > 100 mm Hg. No exclusion if blood pressure is drug treated and in acceptable range. d) High cholesterol: no exclusion even though medication is used e) Diabetes: exclusion if diabetes type I or use of insulin f) Steroid use: exclusion for 4 weeks after application g) Cancer: exclusion h) Other chronic diseases: exclusion depends on the type of disease (for example chronic heart disease, autoimmune disease)

Our SkMC are proliferating myoblasts that have retained the capacity to differentiate. Upon withdrawal of serum and growth factors, differentiation is induced and the cells form multinucleated syncytia.

For efficient differentiation of our SkMC into myotubes, we recommend to use cells that have undergone a maximum of 4-5 population doublings, i.e. not more than 1 additional subculturing step after thawing the original vial. For more details about differentiation, please see the instruction manual of our Skeletal Muscle Cell Media.

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.

PromoCell guarantees at least 15 population doublings (PDs) for Normal Human Dermal Fibroblasts (NHDF). This guarantee is based on internal quality control testing, during which fibroblasts are routinely cultured for 15 PDs.
This corresponds to approximately 6–8 passages, depending on the split ratio used.

What the guarantee means - and what it does not

• The guarantee ensures that the cells can be reliably expanded for a minimum of 15 PDs.
• It does not mean that the cells will senesce immediately after reaching 15 PDs.
• PromoCell does not determine or claim a maximum number of population doublings or passages.

Practical experience
In practice, most NHDF lots can achieve well beyond the guaranteed minimum, and more than 20 passages are commonly possible, depending on:

• culture conditions
• handling
• split ratios
• donor‑specific characteristics

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.

Short protocol:

• Wash the cells with sterile PBS (w/o Ca++/Mg++) or HepesBSS
• Add undiluted accutase to the culture vessel (2 ml per 25 cm²)
• Incubate at room temperature for 5-15 min or at 37°C for faster detachment
• When the majority of the cells has detached, centrifuge the suspension and resuspend the pellet in fresh medium. In most cases, no additional washes or neutralization steps are required.

The trypsin supplied with the PromoCell Detach Kit (C-41200, C-41210, C-41220) is derived from porcine pancreas.

Cell source and localization
PromoCell Human Pericytes from placenta (hPC‑PL, C‑12980) are isolated from microvessels of the human placenta, specifically from the chorionic villi.
 
Population doublings
We guarantee ≥ 10 population doublings (PDs) for our human pericytes.

PromoCell Cell Culture Media “ready‑to‑use” consist of:

• a basal medium, and
• a SupplementMix, in which all required supplements are pre‑mixed in a single tube.

PromoCell Cell Culture Media “Kits” consist of:

• the same basal medium, and
• a SupplementPack, where the supplements are provided in separate vials.

When the SupplementMix or SupplementPack is added to the corresponding basal medium according to the instructions, both formats result in identical complete growth media.