Table 2.

RT-PCR expression levels of neurotrophins and receptors in the synovial fluids of SpA, RA, and OA patients

Patient Groups		RT-PCR results
		TrkA	p75	trkB	trkC	NGF	BDNF	NT-3	NT-4
SpA (n = 16)	median	20	13.4	6.7	7.1	323	92	7.0	7.3
	SD	12	7.7	3.9	6.0	296	113	2.9	5.0
	(range)	(3.6 to 45)	(3.5 to 28)	(1.1 to 17)	(2.4 to 25)	(74 to 1225)	(71 to 444)	(1.3 to 9.6)	(1 to 15)
RA (n = 9)	median	16	25	7.7	11	418	163	7.5	10
	SD	10	12	4.3	3.4	275	101	3.5	7 to 6
	(range)	(8.9 to 40)	(2.3 to 41)	(4.1 to 18)	(4.3 to 14)	(267 to 1104)	(71 to 374)	(0.5 to 11)	(4.9 to 22)
OA (n = 7)	median	4.7	4.8	4.1	6.7	49	137	3.4	8.6
	SD	4.2	3.7	2.8	3.8	37.7	98.5	2.2	3.1
	(range)	(1.7 to 15)	(3.2 to 15)	(1.3 to 9.8)	(3.2 to 15)	(18 to 129)	(25 to 238)	(1.7 to 7.8)	(4.3 to 13)

Table 2 shows the RT-PCR expression levels of mRNA transcripts of four neurotrophins (nerve growth factor (NGF), brain-derived growth factor (BDNF), and neurotrophin (NT)-3, NT-4) and their corresponding receptors (high-affinity receptors tyrosine kinase (trk)A, trkB, trkC and the low-affinity NGF receptor p75) of all 32 patients are shown (see also Figures 1 and 2 for detailed data and statistics).

DD = disease duration given in years; ESR = erythrocyte sedimentation rate; f = female; m = male; PMN = percentage of polymorphonuclear cells of SF leukocytes; OA = osteoarthritis; RA = rheumatoid arthritis; SD = standard deviation; SpA = spondyloarthritis.