In vivo detection of myelin proteins in cervical lymph nodes of MS patients using ultrasound-guided fine-needle aspiration cytology.

Cervical lymph nodes (CLN) have been described to be the first lymphoid draining site of the brain. In this study we used ultrasound guided fine needle aspiration cytology (USgFNAC) to obtain cells, in vivo, from non-enlarged CLN of multiple sclerosis (MS) patients and HCs (HC), and investigated whether myelin proteins could be detected. Macrophages containing myelin basic protein (MBP) and proteolipid protein (PLP) were found in CLN of all MS patients, whereas these could only be detected in a minority of HC. This novel approach allows investigation of the first draining site of the brain for in vivo analysis of the immune regulation of MS.