Technical library

PromoCell skeletal muscle cells (SkMC, C‑12530) are supplied as undifferentiated myoblasts that proliferate under standard culture conditions.
These cells have retained theirl differentiation capacity. Upon withdrawal of serum and growth factors, differentiation is induced and the cells fuse to form multinucleated syncytia (myotubes).

For efficient differentiation of PromoCell Skeletal Muscle Cells (SkMCs) into myotubes, we recommend using cells that have undergone a maximum of 4-5 population doublings.
This corresponds to no more than one additional subculturing step after thawing the original vial. Using cells at early population doublings helps ensure robust differentiation and reliable results.
For detailed differentiation protocols and handling recommendations, please refer to the Instruction Manual for PromoCell Skeletal Muscle Cell Media.

At PromoCell, HUVECs are routinely isolated under antibiotic‑free conditions by applying a tissue‑handling strategy that minimizes microbial contamination from the outset.
 
Key principles of the isolation process
1. Antibiotic‑free tissue transport
- Umbilical cords are obtained from tissue suppliers without the addition of buffers or transport media.
- This prevents microorganisms from being washed into the blood vessels, particularly the umbilical vein.
2. Creation of sterile access points
- Prior to cell isolation, the umbilical cord is cut at both ends using a sterile scalpel.
- This provides sterile cross‑sections, in addition to the naturally sterile vessel lumen.
3. Antibiotic‑free cell isolation and culture
- This handling approach allows the isolation of sterile endothelial cells from the umbilical vein.
- HUVECs can therefore be plated and cultured directly in antibiotic‑free 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

Yes, normal human osteoblasts (HOB) can be expanded in vitro to a limited extent before being used for experiments.
Like other non‑transformed primary cell types, osteoblasts have a finite proliferative capacity. In most laboratories, HOBs are therefore used at low passage numbers, typically up to passage 4 (P4), to ensure reliable and physiologically relevant results.

Accutase can be used directly, without dilution, following this short protocol:

• Wash the cells with sterile PBS (without Ca²⁺/Mg²⁺) or Hepes‑BSS
• Add Accutase to the culture vessel (example: 2-3 ml per 25 cm² or 8 ml per 75 cm² TC flask)
• Incubate for 5-20 min at room temperature, or 37°C for faster detachment
• Once the majority of cells has detached, collect the cell suspension, dilute it with fresh medium
• Centrifuge and resuspend the cell pellet in fresh culture medium

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.

Hematopoietic Progenitor Cell Expansion Medium XF (C‑28021) supplemented with Cytokine Mix E (C‑39890) is stable for up to 2 weeks when stored at 2 - 8°C, and kept protected from light.
For optimal performance, please ensure proper storage conditions throughout this period.