Mechanism of natural killer (NK) cell regulatory role in experimental autoimmune encephalomyelitis

• DOI: 10.1016/j.jneuroim.2005.02.011
• Publication Date: 2005-04-28T13:13:57Z
• Authors: Wen Xu; Gyorgy Fazekas; Hideo Hara; Takeshi Tabira
• Keywords: Encephalomyelitis, Autoimmune, Experimental; Cell Death; Molecular Sequence Data; Cytotoxicity Tests, Immunologic; 3. Good health; Killer Cells, Natural; Mice; 03 medical and health sciences; 0302 clinical medicine; Animals; Amino Acid Sequence; Cells, Cultured

The mechanism of natural killer (NK) cell regulatory role in experimental autoimmune encephalomyelitis (EAE) was studied in SJL/J mice. In vivo experiments showed that NK cell depletion by anti-NK1.1 monoclonal antibody treatment enhanced EAE in mice. To investigate the mechanism, we cultured proteolipid protein (PLP)136-150 peptide-specific, encephalitogenic T cell lines, which were used as the NK cell target. Our results show that NK cells exert a direct cytotoxic effect on autoantigen-specific, encephalitogenic T cells. Furthermore, cytotoxicity to PLP-specific, encephalitogenic T line cells was enhanced by using enriched NK cells as effector cells. However, the cytotoxic effect of NK cells to ovalbumin-specific T line cells and ConA-stimulated T cells could also be detected with a lesser efficiency. Our studies indicate that NK cells play a regulatory role in EAE through killing of syngeneic T cells which include myelin antigen-specific, encephalitogenic T cells, and thus ameliorate EAE.