Q1: Why is the growth slow?
Immediately after resusution, the cell condition is poor and some dead cells may appear. The dead cells can be removed by changing the medium overnight or the next day, or by taking 1ml from the original dish to a new culture dish while changing the medium. The amount of serum in the culture medium can be appropriately increased.
Q2: Why doesn't it detach when blown?
SP2/0 is a semi-adherent cell, which is round and transparent, presenting a string-like appearance. Generally, a 1ml pipette tip is sufficient for blowing and suspending.
Q3: Cell source and authorization
SP2/0 cells are sourced from antibody drug enterprises and have a very good effect when used as antibodies. Most antibody drug enterprises do not have a clear demand for the preparation of hybridoma. After they complete the hybridoma treatment, they need to develop genetic engineering antibodies and then express them using cells such as CHO. They must have clear authorization and clear genetic information for this CHO and other cells. We do not provide genetic information and do not offer authorization.
Q4: The product information uses 1640 medium. Can it be switched to DMEM medium?
Changing the culture medium may lead to unsuccessful cell culture. Upon receipt, it is necessary to use the same RPMI-1640 medium as the original product (Gibco?). For 11875) Medium, after completing the cell culture passage and cryopreservation, you can try to replace it with another medium. When obtaining the sp20 cell line, whether in cryopreservation or resuscitation state, it is necessary to first cultivate the cells to a better state in 1640 medium. Then, if necessary, a semi-medium change method can be adopted (first 50%1640+50%DEME, then 25%1640+75%DEME, and finally 100%DEME). Gradually switch to DEME medium.
Q5: What is 8-AG medium for myeloma cells?
8-AG (also known as 8-nitroguanine) is a basic cytotoxic factor. The synthesis of cellular DNA mainly involves two pathways: the primary pathway and the remedial pathway. The HGPRT enzyme (i.e., hypoxanthine-guanine ribosyltransferase) is the primary synthase for purines in the remedial pathway. Under normal circumstances, cells can synthesize DNA through both of these pathways simultaneously. 8-AG is also a purine and can naturally be regarded as a raw material for DNA synthesis. However, since it is toxic, its presence can kill cells. Myeloma cells with HGPRT enzyme deficiency cannot synthesize DNA through the salvage pathway, and thus can survive. Therefore, all sp2/0 cells screened by 8-AG were HGPRT enzyme-deficient strains.
Q6: Why does it grow slowly
Immediately after resusution, the cell condition is poor and some dead cells may appear. The dead cells can be removed by changing the medium overnight or the next day, or by taking 1ml from the original dish to a new culture dish while changing the medium. The amount of serum in the culture medium can be appropriately increased.
Q7: Why can't it be blown down
SP2/0 is a suspension cell with a round and translucent shape. Generally, you can use a 1ml gun tip to blow and hang it.
Q8: Cell source and authorization
sp2/0 cells are derived from antibody drug companies, and the effect of making antibodies is very good.
After they finish the hybridoma, they have to do genetically engineered antibodies, and then use CHO and other cells to express them; They must have clear authorization and clear genetic information about this CHO and other cells.
We do not provide genetic information and do not provide authorization.
Q9: Can the product information use 1640 medium instead of DMEM medium
Switching to culture medium may result in unsuccessful cell culture. After receiving it, RPMI-1640 (Gibco 11875) medium must be used to the same as the original product medium, and after cell culture subcryopreservation, you can try to replace it with another medium.
When you get the sp20 cell line, whether it is cryopreservation or resuscitation, you must first use 1640 medium to culture the cells to a better state, and then if necessary, you can use the method of semi-change (first 50% 1640 + 50% DEME, then 25% 1640 + 75% DEME, and finally 100% DEME), and gradually change to DEME medium.
Q10: Does SP2/0 culture require frequent re-strengthening with 8-azaguanine? What is the dose of 8AG?
There is no need for frequent rejuvenation. To maintain the genetic stability of HGPRT-SP2/0 cells, 8-nitroguanine can be added for screening every three months or so after continuous culture. The reference dosage of 8-aza-guanine is 0.00013M, or you can refer to the recommended dosage in the product manual on the market. This reagent has certain toxicity. A small amount of cell death is a normal phenomenon. If there is a large amount of death, further dilution and testing are required.
Working principle: 8-Azaguanine is a purine analogue that can inhibit the proliferation of microorganisms, viruses, and tumor cells. In cells containing HGPRT enzyme (i.e., hypoxanthine-guanine phosphoribosyltransferase), 8-Azaguanine is utilized by the cells as a raw material for DNA synthesis. However, since it is toxic, it can cause the death of HGPRT+ cells, while HGPRT- cells can survive.
Common HGPRT-fusion chaperone cells such as SP2/0, FO, Ag14, NS1, etc., can survive in media containing 8-aza-guanine. Therefore, 8-aza-guanine is often used for screening and optimization to ensure that these cells remain sensitive to HAT screening media. Thus, the growth of partner cells that did not participate in the fusion after cell fusion can be effectively inhibited.
Q11: What passage are your SP2/0 cells? I see they have been on the shelf for a long time. How is the quality guaranteed for such an early cell line?
The SP20 cell line is a tumor cell line that can proliferate infinitely and has the characteristic of immortalization. It is no longer restricted by the number of normal cell proliferations. Therefore, the actual generation information of the cells has become blurred, and the traditional concept of cell algebra is no longer applicable. Theoretically, they can proliferate continuously. However, in practice, to ensure cell quality, we will record and monitor the quality of the cell culture process. Moreover, we have a large customer base and our technical services are continuously using this cell line, so we can ensure that this cell can meet the requirements of cell fusion. In addition, we have a complete technical support and after-sales service system. If you encounter any quality issues after receiving it, you can contact us at any time.
Q12: For SP2/0 cell culture, does glutamine need to be added extra? Doesn't 1640 already contain glutamine?
Generally, 1640 medium is contained, but sometimes it may degrade during the storage process. For safety's sake, we suggest adding it