Select Biomarkers on the Day of Anterior Cruciate Ligament Reconstruction Predict Poor Patient-Reported Outcomes at 2-Year Follow-Up: A Pilot Study

Table 2

Inflammatory cytokines and chondrodegenerative markers evaluated on the day of ACL reconstruction [3, 4].

Biomarker	Abbreviation	Volume (Dilution)	CV	LLOD	Number () below LLOD^‡
Cartilage oligomeric matrix protein (μg/mL); Catalog #RD194080200, BioVendor, Asheville, NC	COMP	5 μl; (1:2500)	1.9%	0.4 ng/ml	0 (0%)
Synovial C-terminal crosslinked telopeptide of type II collagen (ng/mL); Cartilaps®, Catalog # AC-10F1, Immunodiagnostic Systems, Inc, Fountain Hills, AZ	CTX-II	40 μl; (None)	4.3%	0.20 μg/L	0 (0%)
Urinary CTX-II normalized to creatinine concentration (ng/mmol); Cartilaps®, Catalog # AC-10F1, Immunodiagnostic Systems, Inc, Fountain Hills, AZ	uCTX-II	40 μl; (None)	3.3%	0.20 μg/L	0 (0%)
Sulfated glycosaminoglycan (μg/mL); Catalog # BP-004, Kamiya Biomedical Company, Seattle, WA	sGAG	25 μl; (None)	1.8%	N/A	0 (0%)
Interleukin-1 alpha (pg/mL); Catalog # K151RBD, Meso Scale Discovery, Rockville, MD	IL-1α	25 μl; (1:2)	9.9%	0.238 pg/ml	4 (18%)
Interleukin-1 beta (pg/mL); Catalog #K151QPD, Meso Scale Discovery, Rockville, MD	IL-1β	25 μl; (1:2)	5.7%	0.033 pg/ml	11 (50%)
Interleukin-1 receptor antagonist (pg/mL); Catalog # DRA00B, R&D Systems, Minneapolis, MN	IL-1ra	100 μl; (None)	4.4%	6.3 pg/ml	0 (0%)
Matrix metalloproteinase 3 plex (MMP-1, MMP-3, MMP-9) (pg/mL); Catalog # K15043C, Meso Scale Discovery, Rockville, MD	MMP-1	5 μl (1:20)	3.5%	1.74 pg/ml	0 (0%)
	MMP-3	5 μl (1:20)	4.5%	4.34 pg/ml	0 (0%)
	MMP-9	5 μl (1:20)	3.5%	14.3 pg/ml	0 (0%)
N-terminal crosslinked telopeptide of type I collagen (nM BCE); Catalog # 9021, Osteomark ® NTx; Alere, Scarborough, ME	NTX-I	25 μl; (1:5)	2.3%	N/A	0 (0%)
Tumor necrosis factor-inducible gene 6 activity; In-house ELISA assay developed by Kraus Laboratory[20]	TSG-6	4 μl; (1:100)	12.9%	1.0U	0 (0%)

All biomarkers measured in synovial fluid with the exception of urinary CTX-II.
CV = mean interassay coefficient of variation.
LLOD = lower limits of detection.