Expression of FasL and Fas/Apo-1 Receptor (CD95) in Malignant Plasma Cell Lines and Their Sensitivity to the Agonistic Anti-Fas MoAb
| Cell Line . | FasL Expression (MSFI)* . | Fas/Apo-1 (CD95) Expression (MSFI)* . | % Anti-Fas MoAb-Induced Apoptosis† . | Survival of Myeloma Cells Coincubated With FasL+ CEM-C7H2 Cells (% control)‡ . |
|---|---|---|---|---|
| ARH-77 | 3.79 | 3.91 | 37 | 116 |
| IM-9 | 2.10 | 11.85 | 62 | 108 |
| LP-1 | 2.40 | 9.83 | 31 | 94 |
| MC/CAR | 3.06 | 7.96 | 44 | 117 |
| NCI-H929 | 5.15 | 1.05 | neg | 98 |
| RPMI-8226 | 5.70 | 4.10 | 51 | 113 |
| U-266 | 5.06 | 1.13 | neg | 99 |
| CEM-C7H2-wt/IC3ρ | 2.40 | 3.60 | 50 | — |
| CEM-C7H2-CrmA/2E8 | 2.10 | 4.30 | 4 | — |
| Cell Line . | FasL Expression (MSFI)* . | Fas/Apo-1 (CD95) Expression (MSFI)* . | % Anti-Fas MoAb-Induced Apoptosis† . | Survival of Myeloma Cells Coincubated With FasL+ CEM-C7H2 Cells (% control)‡ . |
|---|---|---|---|---|
| ARH-77 | 3.79 | 3.91 | 37 | 116 |
| IM-9 | 2.10 | 11.85 | 62 | 108 |
| LP-1 | 2.40 | 9.83 | 31 | 94 |
| MC/CAR | 3.06 | 7.96 | 44 | 117 |
| NCI-H929 | 5.15 | 1.05 | neg | 98 |
| RPMI-8226 | 5.70 | 4.10 | 51 | 113 |
| U-266 | 5.06 | 1.13 | neg | 99 |
| CEM-C7H2-wt/IC3ρ | 2.40 | 3.60 | 50 | — |
| CEM-C7H2-CrmA/2E8 | 2.10 | 4.30 | 4 | — |
MSFI was determined by immunofluorescence staining and FACS analysis and calculated as the ratio of the MSFI achieved with anti-FasL MoAb/isotype-matched control MoAb. Mean values of three independent experiments are given.
Induction of apoptosis in myeloma cells was determined after 8 hours of incubation with anti-Fas MoAb (0.25 μg/mL) using the PI assay.27 Mean values of three independent experiments are given. The standard error was <10% in all cell lines.
Using myeloma cells as targets for FasL+ CEM-C7H2 T cells, cells of the relevant lines were endogeneously labeled with 3[H]-thymidine and incubated with an excess of effector T cells (E/T ratio 10:1) for 72 hours (JAM test30 ). Mean values (n = 8) were used to calculate the percentage of myeloma cell survival.
ρ CEM-C7H2 T-ALL cells served as a FasL positive control.