M-07e

The M-07e cell line is a subline derived from the original M-07 human leukemic cell line, which was established from the peripheral blood of a 6-month-old girl diagnosed with acute megakaryoblastic leukemia (AML M7). This particular subline was isolated to create a factor-dependent cell line that requires interleukin-3 (IL-3) or granulocyte macrophage colony-stimulating factor (GM-CSF) for growth, even in the presence of fetal calf serum. M-07e cells exhibit robust proliferation in response to a variety of cytokines, including GM-CSF, interferons (IFN-alpha, IFN-beta, IFN-gamma), IL-2, IL-3, IL-4, IL-6, IL-15, nerve growth factor (NGF), stem cell factor (SCF), tumor necrosis factor-alpha (TNF-alpha), and thrombopoietin (TPO). However, their dependency on IL-3 or GM-CSF for sustained growth makes them a valuable tool in bioassays designed to measure the biological activity of these specific cytokines.

Notably, M-07e cells are highly sensitive to IL-3 and GM-CSF, making them ideal for use in assays where detecting low levels of these cytokines is crucial. For instance, bioassays using M-07e cells can detect as little as 25-50 pg/mL of IL-3 or GM-CSF, making it comparable to or even more sensitive than traditional assays like the CFU-GM or CML blast proliferation assays. However, the cell line has a tendency to become cytokine-independent within 3-4 weeks in culture, likely due to the outgrowth of cytokine-independent subpopulations, which suggests careful monitoring is necessary when using these cells for long-term studies. The availability of exome and RNA sequence data further enhances the utility of M-07e cells in research focused on leukemia and hematopoiesis.

M-07e cells have also been employed to establish a quantitative bioassay for GM-CSF and IL-3, which is essential in both clinical and research settings. The bioassay developed with this cell line has proven to be convenient, reliable, and sensitive, making it particularly useful for assessing the pharmacological effects of hematopoietic growth factor therapies. The detailed responsiveness of M-07e cells to various cytokines, combined with their well-documented growth characteristics, underscores their value in experimental hematology, particularly in studies related to leukemia and the therapeutic application of cytokines.

37°C, 5% CO₂, humidified atmosphere.

1. Confirm that the vial remains deeply frozen upon delivery, as cells are shipped on dry ice to maintain optimal temperatures during transit.

2. Upon receipt, either store the cryovial immediately at temperatures below -150°C to ensure the preservation of cellular integrity, or proceed to step 3 if immediate culturing is required.

3. For immediate culturing, swiftly thaw the vial by immersing it in a 37°C water bath with clean water and an antimicrobial agent, agitating gently for 40-60 seconds until a small ice clump remains.

4. Perform all subsequent steps under sterile conditions in a flow hood, disinfecting the cryovial with 70% ethanol before opening.

5. Carefully open the disinfected vial and transfer the cell suspension into a 15 ml centrifuge tube containing 8 ml of room-temperature culture medium, mixing gently.

6. Centrifuge the mixture at 300 x g for 3 minutes to separate the cells and carefully discard the supernatant containing residual freezing medium.

7. Gently resuspend the cell pellet in 10 ml of fresh culture medium. For adherent cells, divide the suspension between two T25 culture flasks; for suspension cultures, transfer all the medium into one T25 flask to promote effective cell interaction and growth.

8. Adhere to established subculture protocols for continued growth and maintenance of the cell line, ensuring reliable experimental outcomes.

Mycoplasma contamination is excluded using both PCR-based assays and luminescence-based mycoplasma detection methods.

To ensure there is no bacterial, fungal, or yeast contamination, cell cultures are subjected to daily visual inspections.

For long-term preservation, place vials in vapor-phase liquid nitrogen at about −150 to −196 °C. Storage at −80 °C is acceptable only as a short interim step before transfer to liquid nitrogen.

Cryopreserved cell lines are shipped on dry ice in validated, insulated packaging with sufficient refrigerant to maintain approximately −78 °C throughout transit. On receipt, inspect the container immediately and transfer vials without delay to appropriate storage.

At Cytion, we stand behind the quality and viability of our products. We guarantee that our cells will be viable at the start of culture for 60 days after shipment from our facilities. We assure that all materials conform to the specifications described in the Certificate of Analysis and/or Product Sheet.

For full details, please refer to our Warranty Statement.