Technical library

No. This is not recommended.
Freshly isolated CD14⁺ monocytes should be seeded immediately into Monocyte Attachment Medium after isolation.
Adding an intermediate culture step before the attachment and differentiation phase is strongly discouraged, because monocytes change their biological characteristics very rapidly in vitro.
To ensure controlled and reproducible macrophage differentiation, freshly isolated CD14⁺ monocytes should therefore be used immediately, without prior cultivation.

When assessing osteogenic differentiation of MSCs by Alizarin Red staining, the addition of PBS in the final step serves an important purpose.

Reason
PBS provides a buffered environment that enhances the precipitation of Alizarin Red, resulting in a more intense and stable staining signal.

Handling recommendation

• Do not aspirate the PBS before analysis.
• Leave the PBS on the cells and analyze the sample immediately after staining and washing.

Prolonged storage without embedding may cause the Alizarin Red dye to bleed, which can negatively affect staining quality and data interpretation.

The prophylactic use of antibiotics in cell culture is generally discouraged for several important reasons.
First, antibiotics can create a false sense of security and may lead users to develop poor aseptic techniques. As a result, low‑level contaminations can occur and remain undetected for extended periods of time. These unnoticed contaminations may then spread within the laboratory and contribute to the development of antibiotic‑resistant strains. 
Second, the routine presence of antibiotics can facilitate mycoplasma infections, which are often introduced together with bacteria or fungi and are not effectively controlled by standard antibiotics. 
Finally, antibiotics are known to have direct negative effects on eukaryotic cells, including:

• reduced proliferation rates of primary cells
• altered cellular metabolism
• effects on differentiation and gene expression

These side effects can compromise experimental reliability and data interpretation. 
For a more detailed discussion, please refer to our blog article “Antibiotics in Cell Culture: Friend or Enemy?”. 

To minimize the formation of precipitates when preparing MSC Adipogenic Differentiation Medium 2, please follow these recommendations:
 
Recommended handling

• Ensure that the SupplementMix is at room temperature before adding it to the MSC Adipogenic Basal Medium 2.
• After thawing, gently invert the supplement tube several times to help dissolve any visible precipitates before use.

Important note
Do not filter the basal medium, supplements, or the complete medium. Filtration may remove critical components required to induce or promote adipogenic differentiation, which can result in a reduced differentiation efficiency.

Yes. Human mesenchymal stem cells (hMSCs) require a few cell‑type‑specific handling adjustments compared to most other primary cell types.

Key differences in MSC cultivation:

• Early medium change after seeding: When using MSC Growth Medium XF (C‑28019), we recommend replacing the medium 3–4 hours after seeding. In contrast, for most other cell types and growth media (including MSC Growth Medium 2), the first medium change is typically performed 16–24 hours after seeding.
• Pre‑coating of culture vessels: When using MSC Growth Medium XF, MSC Neurogenic Differentiation Medium, MSC Adipogenic Differentiation Medium 2, or MSC Osteogenic Differentiation Medium, tissue culture vessels must be pre‑coated as described in the Instruction Manual.
• Detachment method: We strongly recommend using Accutase (C‑41310) for detaching MSCs, as it is gentler and helps preserve cell viability. If trypsin is used, the contact time should not exceed 2 minutes.

Yes. Light flocculation can occur after thawing supplements that contain ECGS/heparin or BPE. This phenomenon is normal and does not affect the activity or performance of the medium. 
If desired, the precipitate can be removed by centrifugation under sterile conditions.
For optimal handling, we recommend thawing supplements (SupplementMix or SupplementPack) at 15-25°C, rather than at higher temperatures.

PromoCell human pulmonary artery endothelial cells (HPAEC) and human pulmonary artery smooth muscle cells (HPASMC) are isolated from the proximal pulmonary artery.

The intended use of PromoCell products is defined in PromoCell's Terms & Conditions, specifically in the section "VIII. Intended use of goods and right of use".
Accordingly, PromoCell products are designated for in vitro research use only and are not intended for diagnostic, therapeutic, or in vivo applications.

The activation of macrophages is generally complete after 24 hours.
However, if you wish to maintain the activated state over a longer period of time (e.g. several days), fresh activation factors should be added with every medium change.
Stopping the addition of activation factors after 24 hours may lead to a gradual loss of the activation status during prolonged culture.

Yes. The 5 ml Cytokine Mix E (C‑39891) can be safely aliquoted into 5×1 ml portions.