MI is an interleukin-2 (IL-2) independent Natural Killer Cell line derived from the NK-92®
cell line by transfection. NK-92®
is an interleukin-2 (IL-2) dependent Natural Killer Cell line derived from peripheral blood mononuclear cells from a 50 year old Caucasian male with rapidly progressive non-Hodgkin's lymphoma. The parental cells were transfected with human IL-2 cDNA in the retroviral MFG-hIL-2 vector by particle-mediated gene transfer. The transfection is stable.
NK-92® and this derivative cell line NK-92® MI have the following characteristics: surface marker positive for CD2, CD7, CD11a, CD28, CD45, CD54 and CD56 bright; surface marker negative for CD1, CD3, CD4, CD5, CD8, CD10, CD14, CD16, CD19, CD20, CD23, CD34 and HLA-DR.
The parental IL-2 dependent cell line is available as ATCC CRL-2407 (NK-92® ). NK-92® MI was shown to contain, express, and synthesize the hIL-2.
A culture submitted to the ATCC in September of 1998 was found to be contaminated with mycoplasma. Progeny were cured by a 21-day treatment with BM Cycline. The cells were assayed for mycoplasma, by the Hoechst stain, PCR and the standard culture test, after a six-week period following treatment. All tests were negative.
ATCC confirmed this cell line is positive for the presence of Epstein-Barr viral DNA sequences via PCR.