Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska University Hospital, Gothenburg University, Gothenburg, Sweden.
Equine Vet J. 2019 Sep;51(5):674-680. doi: 10.1111/evj.13082. Epub 2019 Mar 6.
Molecular serum markers that can identify early reversible osteoarthritis (OA) in horses are lacking.
We studied serum concentrations of a novel cartilage oligomeric matrix protein (COMP) neo-epitope in horses subjected to short-term exercise and with acute lameness. The effects of circadian rhythm and age were also evaluated.
Longitudinal studies in healthy horses and cross-sectional comparison of lame and non-lame horses.
Sera were collected from five horses before and after short-term interval exercise and during full-day box rest. Sera from 32 acutely lame horses were used to evaluate age-related effects. Independent samples from control horses (n = 41) and horses with acute lameness (n = 71) were included. COMP neo-epitope concentrations were analysed using custom-developed inhibition ELISAs validated for equine serum. The presence of COMP neo-epitope was delineated in healthy and osteoarthritic articular cartilage with immunohistochemistry.
COMP neo-epitope concentrations decreased after speed training but returned to baseline levels post-exercise. No correlations between age and serum COMP neo-epitope concentrations were found (r = 0.0013). The mean (±s.d.) serum concentration of COMP neo-epitope in independent samples from non-lame horses was 0.84 ± 0.38 μg/mL, and for lame horses was 5.24 ± 1.83 μg/mL (P<0.001). Antibodies against COMP neo-epitope did not stain normal articular cartilage, but intracytoplasmic staining was found in superficial chondrocytes of mild OA cartilage and in the extracellular matrix of moderately osteoarthritic cartilage.
ELISA was based on polyclonal antisera rather than a monoclonal antibody. There is a sex and breed bias within the groups of horses, also it could have been of value to include horses with septic arthritis and tendonitis and investigated joint differences.
This COMP neo-epitope can be measured in sera, and results indicate that it could be a biomarker for pathologic fragmentation of cartilage in connection with acute joint lameness.
目前缺乏能够识别早期可逆性马骨关节炎（OA）的分子血清标志物。
我们研究了在短期运动和急性跛行的马中新型软骨寡聚基质蛋白（COMP）新表位的血清浓度。还评估了昼夜节律和年龄的影响。
健康马的纵向研究和跛行与非跛行马的横断面比较。
在短期间歇运动前后和全天箱休息期间采集五匹马的血清。使用 32 匹急性跛行马的血清来评估与年龄相关的影响。包括对照组马（n=41）和急性跛行马（n=71）的独立样本。使用针对马血清开发的定制抑制 ELISA 分析 COMP 新表位浓度。使用免疫组织化学描绘健康和骨关节炎关节软骨中的 COMP 新表位。
速度训练后 COMP 新表位浓度降低，但运动后恢复到基线水平。未发现年龄与血清 COMP 新表位浓度之间存在相关性（r=0.0013）。非跛行马独立样本的平均（±s.d.）血清 COMP 新表位浓度为 0.84±0.38μg/mL，跛行马为 5.24±1.83μg/mL（P<0.001）。针对 COMP 新表位的抗体未染色正常关节软骨，但在轻度 OA 软骨的浅层软骨细胞和中度骨关节炎软骨的细胞外基质中发现细胞内染色。
ELISA 基于多克隆抗血清，而不是单克隆抗体。马的各个组存在性别和品种偏见，此外，包括患有脓毒性关节炎和腱炎的马并研究关节差异可能会很有价值。
可以在血清中测量这种 COMP 新表位，结果表明它可能是与急性关节跛行相关的软骨病理性碎裂的生物标志物。
