Table III.
MuSK positive screening result validation by RIA
| ID/specimen | Δ % positive screening CBA | Δ cpm RIA |
|---|---|---|
| HD (T1D) 1 | 71.6 | ND |
| HD (T1D) 2 | 35.6 | ND |
| SLE 1 | 31.9 | 71 |
| SLE 2 | 26.0 | −68 |
| SLE 3 | 22.8 | −145 |
| SLE 4 | 13.8 | −32 |
| HD (SLE) | 14.4 | −51 |
| SLE-Neuro | 17.8 | ND |
| RA 1 | 45.2 | −62 |
| RA 2 | 43.2 | −59 |
| HD (RA) | 37.5 | −20 |
| HD (MS) 1 | 39.0 | 32 |
| HD (MS) 2 | 36.5 | 72 |
| Positive control CBA | 91.0 | NA |
| Negative control CBA | 0.2 | NA |
| Positive control RIA | NA | 23204 |
| Negative control RIA | NA | 85 |
Results of validation RIAs (5 μL of serum, whole-antigen) are reported. Δ cpm cutoff ranged from 203 to 359 (mean + 3SD). HD: healthy donors, T1D: type 1 diabetes, SLE: systemic lupus erythematosus, RA: rheumatoid arthritis, MS: multiple sclerosis, CBA: cell-based immunofluorescence assay, RIA: radioimmunoassay, cpm: counts per minute, ND: not done due to inadequate serum quantity.