Regulation of T cell activation though neurons and astrocytes

초록

When brain tissue damaged, various immune cells are introduced to cause neuro inflammation. Astrocytes protect neurons and interact with T cells to play an important role in brain inflamm ation. However, it is difficult to study how brain cells affect the T cell activation in vivo due to the restricted number of T cells in brain tissues. Therefore, we established a co culture system of lymphocytes in vitro either with astrocytes or neurons. Neonatal cortex astrocytes and embryonal cortex neurons were isolated from mice and co cultured with lymphocytes from spleen and lymph node. For the activation of T cells, lymphocytes were activated by anti CD3/CD28 antibodies. In the presence of astrocyt es or neurons, the percentage of effector CD44+CD62L T cells were increased, while IL 4, IL 13, IL 17A, and IFN γ cytokines were decreased in the culture medium. In contrast to the neurons, astrocytes induced IL 6 and nitric oxide (NO) expression. Express ion of IFN γ was partially restored by NO inhibitor L NMMA. Intriguingly, both brain cell mediated inhibition of CD62L expression was fully restored by rapamycin or Ly294002. Probably neurons and astrocytes can influence the intrinsic signals of T cells to maintain effector T cells which probably affect the brain inflammation.