Expression and function of MDR proteins in leukemic cell lines
. | % MDR1+ cells* . | . | . | . | DiOC2 efflux . | . | ||
|---|---|---|---|---|---|---|---|---|
| Cell line . | MRK16 . | JSB1 . | % MRP1+ cells* . | % LRP+ cells* . | D efflux† . | D ± CsA‡ . | ||
| HL-60 | 7 | 1 | 0 | 0 | 0.28 (mod) | 0.06 | ||
| THP-1 | 69 | 48 | 70 | 22 | 0.31 (mod) | 0.05 | ||
| NB-4 | 40 | 1 | 0 | 0 | 0.17 (neg) | 0.04 | ||
| KG-1 | 11 | 26 | 0 | 9 | 0.43 (strong) | 0.33 | ||
. | % MDR1+ cells* . | . | . | . | DiOC2 efflux . | . | ||
|---|---|---|---|---|---|---|---|---|
| Cell line . | MRK16 . | JSB1 . | % MRP1+ cells* . | % LRP+ cells* . | D efflux† . | D ± CsA‡ . | ||
| HL-60 | 7 | 1 | 0 | 0 | 0.28 (mod) | 0.06 | ||
| THP-1 | 69 | 48 | 70 | 22 | 0.31 (mod) | 0.05 | ||
| NB-4 | 40 | 1 | 0 | 0 | 0.17 (neg) | 0.04 | ||
| KG-1 | 11 | 26 | 0 | 9 | 0.43 (strong) | 0.33 | ||
Mod indicates moderate; and neg, negative.
Surface MDR1 (MRK16) and intracellular MDR1 (JSB1), MRP1, and LRP expression were measured by indirect immunofluorescence.
Difference values (D; range, 0-1.0) as measured by Kolmogorov-Smirnov (KS) statistics for samples loaded with DiOC2 and allowed to efflux the drug for 90 minutes at 37°C. D value definition for efflux is as follows: weak, 0.20 ≤ D < 0.25; moderate, 0.25 ≤ D < 40; strong, D ≥ 0.40.21
Difference values by KS statistics for efflux in presence versus absence of CsA. D > 0.15 was defined as significant.21