The role of selected NKG2DLs such as MICA, MICB and ULBP4 as potential markers in multiple sclerosis.

The interaction between natural killer group 2 members D and their ligands (NKG2D-NKG2DLs) may play a role in the immunopathology of multiple sclerosis (MS). Owing to their measurable presence in biofluids, soluble NKG2DLs may serve as potential biomarkers for disease activity. NKG2DL family proteins have been previously investigated in the central nervous system (CNS) or biofluids of MS patients but have typically been analyzed individually rather than collectively. To our knowledge, this was the first study to comprehensively evaluate soluble forms of MHC class I chain-related proteins A and B (MICA and MICB), UL16 binding protein 4 (ULBP4), and neurofilament light chains (NFLs) in the serum and cerebrospinal fluid (CSF) of relapsing-remitting MS patients, patients with multifocal demyelinating CNS damage (Pre-MS observation group), and a control group. Results revealed comparable levels of NKG2DLs in the serum and CSF between the groups. This suggested that they may not be suitable as diagnostic and predictive markers in MS. However, the analysis confirmed the established significance of NFL, demonstrating its elevated levels in CSF and serum from MS patients compared with other groups, along with a notable correlation between NFL levels in serum and CSF.