MM.1S

The MM.1S cell line is part of the MM.1 series, which was developed from a single patient with multiple myeloma (MM) to study various stages of disease progression and response to glucocorticoid (GC) therapy. MM.1S is specifically sensitive to glucocorticoids, such as dexamethasone, and serves as a model to investigate the mechanisms of GC-induced apoptosis in multiple myeloma cells. This sensitivity makes MM.1S a crucial tool for studying the early phases of MM treatment and the cellular pathways leading to GC responsiveness.

MM.1S cells, like other MM.1 lines, exhibit typical myeloma morphology, including round cells with eccentrically located nuclei, many of which are binucleated or multinucleated. These cells express characteristic markers of plasma cells, such as CD38 and PCA-1, while lacking typical B-cell markers like CD19 and CD20, reflecting their terminally differentiated status as plasma cells. They also exhibit high levels of immunoglobulin lambda (λ) light chain expression, consistent with their origin. This cell line has been vital for exploring pathways of drug action, resistance, and apoptosis in MM, especially in the context of GC treatment.

One of the key features of MM.1S is its reliance on functional glucocorticoid receptors (GR) for drug responsiveness. In MM.1S, high levels of wild-type GR enable dexamethasone to induce apoptosis effectively, providing a valuable system for studying the molecular events underlying this process. This line is often compared to its resistant counterpart, MM.1R, to investigate the mechanisms of GC resistance, a critical issue in the treatment of MM. Together, the MM.1S cell line offers insights into drug sensitivity, disease progression, and potential therapeutic strategies for multiple myeloma.

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.