Table 5.

Comparison of the differential expressions of putative disease markers.

Gene	Differential Expression* (hTERT-OA 13A FLS/hTERT-RA 516 FLS) (passage 25)	Gene Name	Differential Expression** (OA synovium/RA synovium)	Mean Absolute Deviation**†	Description
Group I
IL1R1	2.05	ILIR1	2.15		Interleukin 1 receptor, type I
P4HA2	2.37	P4HA2	1.93		Procollagen-proline, 2-oxoglutarate 4-dioxygenase
COL3A1	2.35	COL3A1	1.96		Collagen, type III, alpha 1
SORD	0.49	SORD	0.59		Hyman L-iditol-2 dehydrogenase
PGK1	0.58	PGK1	0.24		Phosphoglycerate kinase (alternatively spliced)
EXT1	2.47	EXT1	0.61		Homo sapiens insert cDNA clone YP87D03.
LIMK2	0.36	LIMK2	1.38		LIM domain kinase 2, transcript variant 2a
Group II
RPL15	2.23	NA	NA	1.4	ESTs, AI939308
CXCL2	2.82	NA		1.32	Human gro-beta mRNA, complete cds
GSTT1	1.78	NA		1.30	Glutathione S-transferase theta 1
PPP2R5C	1.65	NA		1.42	Homo sapiens mRNA; cDNA DKFZp761H0317
FN1	0.40	NA		1.40	Homo sapiens mRNA for MSF-FN70 (FN gene)

^*This study. Numbers are the ratio of the relative expression level of a gene in hTERT-OA 13A FLS to relative expression level of a gene in hTERT-RA 516 FLS.

^**Previously reported¹⁶. Numbers are the ratio of the relative expression level of a gene in OA synovium to relative expression level of a gene in RA synovium.

^†Mean absolute deviation of the expression levels of a gene in OA synovium from the mean of the expression levels of a gene in normal synovium. Group I: The genes that displayed either elevated expression or decreased expression in all OA synovium samples compared to all RA synovium samples. Group II: The genes that displayed greater differential gene expression (judged by mean absolute deviation) between OA synovium and RA synovium, although in some OA synovium samples expression of the gene of interest was up and in other OA synovium samples expression was down compared to RA synovium samples¹⁶.