Table 2.

SELDI-TOF MS unpaired serum protein peaks differentially expressed in SJIA before and after conventional therapy

Mass (m/z)	P
4504	0.0004
11650	0.0003
11691	0.0002
14047	0.00001
28107	0.000002
28958	0.0000005
39871	0.0004
46175	0.0008
60806	0.0002

Differences between mass spectra of pretreatment sera of 8 patients who went on to respond to conventional therapy compared with post-treatment sera of 15 patients who responded poorly to conventional therapy. Only variables with nonparametric P values of <0.001 are listed, from 272 peak clusters surveyed. These peaks may represent a profile predictive of response or nonresponse to conventional therapy. SELDI-TOF MS, surface-enhanced laser desorption/ionization time-of-flight mass spectrometry; SJIA, systemic juvenile idiopathic arthritis.