Table 1.
Patient demographics and characteristics.
| JDM Patient | Sex | Race | Duration of untreated disease at diagnosis (months) | Age at sample collection (yrs) | MSA | Treatment Naive | RNAseq | Validation Experiments | Clinically Inactive JDM Experiments |
|---|---|---|---|---|---|---|---|---|---|
| 1 | M | C | 3 | 3.2 | negative | * | X | X | |
| 2 | F | C | <3 | 8.2 | p155/140 | * | X | ||
| 2b | F | C | 14.2 | X | |||||
| 3 | M | C | 4 | 12.1 | MDA5 | X | |||
| 4 | F | C | <1 | 12.8 | MJ | * | X | X | |
| 5 | M | C | 4 | 10.7 | p155/140 | * | X | ||
| 6 | F | C | 1 | 7.9 | MDA5 | * | X | ||
| 6b | F | C | 9.8 | X | |||||
| 7 | F | C | <1 | 14.5 | Mi-2 | * | X | ||
| 8 | M | C | <1 | 2.6 | MJ | * | X | ||
| JDM PT CID | Sex | Race | |||||||
| 9 | F | C | 2 | 10.3 | X | ||||
| 10 | F | C | 1.5 | 8.7 | X | ||||
| HPC | |||||||||
| 1 | M | C | 7.5 | X | X | ||||
| 2 | F | C | 9.4 | X | |||||
| 3 | F | C | 13.4 | X | X | ||||
| 4 | F | C | 18.3 | X | |||||
| 5 | M | C | 10.1 | X | |||||
| 6 | F | C | 8.2 | X | |||||
| 7 | F | C | 10.2 | X | |||||
| 8 | M | C | 3.2 | X | |||||
| 9 | F | C | 9 | X | |||||
| 10 | F | C | 10 | X | |||||
| 11 | F | C | 11 | X | |||||
| 12 | F | C | 14 | X | |||||
Average age of the 10 JDM patients and 10 healthy pediatric controls (HPC) used in these studies were 9.58 and 10.35, respectively with similar sex distributions between each group. The average age of the 8 new onset JDM patients and 8 heathly controls were respectively 9 and 10.03, and the average age for the 4 new onset JDM patients used in the RNAseq study was 9.05 and 12.15 years, respectively, The duration of untreated disease in JDM patients was similar in the RNAseq cohort (2.75 months average with a standard deviation of 1.25 months). All ten JDM patients were negative for myositis-associated autoantibodies (MAA). Six treatment-naïve JDM patients and 6 age-matched controls (AMCs) (including 1 JDM patient and AMC from the RNAseq cohort) were used in additional validation experiments. The average age of the 6 JDM patients used for validation experiments was 7.95 years and 8.76 years for the AMCs with 3 males and 3 females in each group. Four patients (two of whom also had treatment naïve samples in the study) with clinically inactive disease (CID) on medication were used in the follow-up studies. Other abbreviations: C (Caucasian), MSA (myositis-specific antibodies), MDA5 (anti melanoma differentiation associated gene 5), an MJ also known as nuclear matrix protein 2 (NXP-1), and Mi2 and p155/140 are also MSAs.