Table 1. IP production and surface expression of wild type and mutant CCR5 receptors.
| IP Production | FACS analysis | |||
| CCR5 Receptor Construct | Basal | Stimulated | Mean Fluorescence Intensity | Cells gated |
| (CPM) | (CPM) | (% wild type) | (%) | |
| Wild type | 2 263±417 (9) | 15 684±1 198 | 100 | 86±0.5 |
| Thr2.56(82)Lys | 4 783±1 007a (9) | 4 516±915 | 6±1.5 | 8±0.5 |
| Thr2.56(82)Pro | 9 004±3284a (6) | 12 382±3 161 | 92±15 | 47±6.7 |
| Thr2.56(82)Arg | 2 358±373 | 2 827±802 | 19±3 | 51±0.8 |
| Asp3.49(125)Ala | 1 811±368 | 1 799±680 | 11±1.7 | 46±1.8 |
| Asp3.49(125)Asn | 1 338±338 | 2827±802 | 47±8.5 | 74±0.3 |
| Arg6.32(225)Ala | 1 438±360 | 6 197±2 550 | 63±10 | 57±11 |
| Arg6.32(225)Asp | 1 664±259 | 6 446±1 556 | 72±24 | 61±19 |
| Arg6.32(225)Glu | 1 808±418 | 6 697±2 022 | 43±12 | 69±5.0 |
| T2.56(82)K/R6.32(225)Q | 14 500±4 321a (4) | 14 187±4 320 | 51±13 | 48±7.5 |
| T2.56(82)P/R6.32(225)Q | 15 540±6 929a (4) | 18 038±6 700 | 80±21 | 58±7.9 |
a
significantly different from wild type, p<0.05.
To assess constitutive- and ligand-stimulated IP production, HEK-Gqi cells transiently expressing wild type or mutant CCR5 receptors were labeled with [H3]-myo-inositol and incubated with buffer (Basal) or MIP-1β (10−7 M, Stimulated). To assess cell surface expression of receptors HEK 293 cells transiently transfected with wild type or mutant CCR5 constructs were incubated with PE-2D7 antibody before FACS analysis. Every experiment included wild type CCR5 and mock transfected cells. Data are means ± SEM calculated from at least three independent experiments performed in duplicate.