Can the MACSelect Systems be used for every cell line?

Virtually any mammalian cell line can be selected using the MACSelect Systems. Consider the following points when selecting which system to use:

  • The MACSelect LNGFR System works for most cell types and is our first recommendation since the plasmid carries an IRES element.
  • Due to its SV40 ori, the pMACS 4 vector can replicate in COS cells or other cell lines transformed with SV40 or that contain an integrated T antigen. When working with such cell lines, any co-transfected plasmid should also contain the SV40 ori. Otherwise, the relative amounts of co-transfected plasmids will be out of balance, resulting in high amounts of truncated CD4 receptor and low amounts of target protein.
  • The MACSelect 4 System can be used in virtually all CD4 negative cell lines. When working with human T cell lines or human monocyte cell lines, the MACSelect Kk System or MACSelect LNGFR System should be used, as these cell lines may possibly express CD4.
  • The pMACS Kk vector uses the truncated mouse MHC class I molecule of the H2-Kk haplotype as a selection marker. This molecule is only expressed in very few, rarely used mouse strains (e.g., AKR/J or CBA/CA). Cells derived from these mouse strains already express H-2Kk, so the MACSelect Kk System cannot be used in these cells.
  • The MACSelect Kk System must be used with cell lines that express ß-2 microglobulin, which is required for the expression of H-2Kk. In some tumor cell lines such as adenocarcinoma cell lines, ß-2 microglobulin expression is down-regulated, so we recommend using another system such as the MACSelect 4 System.
  • When using adherent cells that must be harvested with trypsin, we recommend the MACSelect Kk System because the H-2Kk molecule is trypsin resistant, whereas the CD4 molecule is not.
  • The two promoters SV40 and H-2Kk also offer the advantage of different expression kinetics of the CD4 or H-2Kk molecule. Generally, CD4 expression occurs earlier than H-2Kk expression.