Temporal reliability of cytokines and growth factors in EDTA plasma

BMC Research Notes

Table 3 Spearman correlations between the regular and high-sensitivity assays ^a, NSHDS and clinical research study subjects combined (n = 54 samples)

Biomarker	LLD (pg/mL)		% of samples above LLD		% of samples above LLD that required extrapolation^b		n samples used to compute r_s	Spearman correlation coefficient (r_s)	r_s p-value
	Regular assay	High-sensitivity assay	Regular assay (%)	High-sensitivity assay (%)	Regular assay (%)	High-sensitivity assay (%)
IL-1β	15	0.06	41	100	41	0	22	0.17	0.45
IL-2	6	0.16	52	100	64	0	28	0.18	0.36
IL-4	5	0.13	100	100	0	0	54	0.06	0.65
IL-5	3	0.01	0	100	N/A	2	N/A	N/A	N/A
IL-6	3	0.10	35	100	68	0	19	0.35	0.13
IL-7	10	0.12	50	98	93	0	27	0.11	0.59
IL-8	3	0.11	100	100	26	0	54	0.45	0.0007
IL-10	5	0.15	83	100	91	0	45	0.23	0.13
IL-13	10	0.48	98	100	81	0	53	-0.13	0.37
TNFα	10	0.05	100	100	66	0	54	0.15	0.28
IFNγ	5	0.29	100	100	0	0	54	0.08	0.56

Note: All available plasma samples were used for these analyses, i.e., a maximum of 36 samples for the NSHDS and 18 samples for the clinical research subjects.
^a Regular assay kit from Biosource and high-sensitivity (hs) assay kit from Linco/Millipore
^b Values were extrapolated beyond the lowest point on the standard curve if their florescence intensity reading was above background florescence intensity. If florescence intensity was less than background florescence intensity, values were considered to be below the lower limit of detection.

ISSN: 1756-0500