PDF(Pubmed)
Abstract：
Early diagnosis of osteoarthritis (OA) is critical for effective cartilage repair. However, lack of blood vessels in articular cartilage poses a barrier to contrast agent delivery and subsequent diagnostic imaging. To address this challenge, we proposed to develop ultra-small superparamagnetic iron oxide nanoparticles (SPIONs, 4 nm) that can penetrate into the matrix of articular cartilage, and further modified with the peptide ligand WYRGRL (particle size, 5.9 nm), which allows SPIONs to bind to type II collagen in the cartilage matrix and increase the retention of probes. Type II collagen in the cartilage matrix is gradually lost with the progression of OA, consequently, the binding of peptide-modified ultra-small SPIONs to type II collagen in the OA cartilage matrix is less, thus presenting different magnetic resonance (MR) signals in OA group from the normal ones. By introducing the AND logical operation, damaged cartilage can be differentiated from the surrounding normal tissue on T1 and T2 AND logical map of MR images, and this was also verified in histology studies. Overall, this work provides an effective strategy for delivering nanosized imaging agents to articular cartilage, which could potentially be used to diagnosis joint-related diseases such as osteoarthritis.
摘要：
骨关节炎（OA）的早期诊断对于有效的软骨修复至关重要。然而,关节软骨中缺乏血管对造影剂输送和随后的诊断成像构成障碍。为了应对这一挑战，我们建议开发超小型超顺磁性氧化铁纳米粒子(SPIONS，4nm），可以渗透到关节软骨的基质中，并用肽配体WYRGRL进一步修饰（粒径，5.9nm),这允许SPION与软骨基质中的II型胶原蛋白结合并增加探针的保留。软骨基质中的Ⅱ型胶原跟着OA的进展而逐步丧失，因此,肽修饰的超小SPIONs与OA软骨基质中II型胶原蛋白的结合较少，因此，OA组中的磁共振（MR）信号与正常组不同。通过引入AND逻辑运算,在T1和T2和MR图像的逻辑图上，可以将受损的软骨与周围的正常组织区分开来，这在组织学研究中也得到了证实。总的来说,这项工作为关节软骨提供了一种有效的纳米显像剂，这可能被用于诊断关节相关疾病，如骨关节炎。
