Detection of early cartilage damage using targeted nanosomes in a post-traumatic osteoarthritis mouse model

Osteoarthritis (OA) is a major cause of pain and disability in the US. A problem with early intervention is that it is very difficult to detect OA before irreversible damage has already occurred. This study characterizes a novel method of early OA detection in a mouse model of post-traumatic osteoarthritis (PTOA) using fluorescent nanosomes. In this investigation, knee injury was induced in mice by compressive loading. Nanosomes encapsulating fluorescent dye and conjugated to collagen type II antibody were utilized to detect cartilage damage in vivo. Cartilage damage and OA progression were detected by the use of fluorescence-imaging (IVIS) and histopathology. Histopathology analyses showed that mild osteoarthritic changes had occurred. This corresponded with a higher fluorescence on IVIS imaging due to more nanosome binding. These results suggest that theragnostic nanosomes may be useful for detection of early PTOA as well as for targeted delivery of interventional agents. From the Clinical Editor: With the aging population, osteoarthritis now poses a significant problem worldwide. Early detection may help slow the progression of the disease. In this study, the authors described the use of fluorescent nanosomes to detect early cartilage damage in a mouse model of osteoarthritis. This detection method may also prove to be useful for targeted delivery of drugs in the future.