| First Author | Grebing M | Year | 2016 |
| Journal | Glia | Volume | 64 |
| Issue | 3 | Pages | 407-24 |
| PubMed ID | 26496662 | Mgi Jnum | J:227624 |
| Mgi Id | MGI:5702337 | Doi | 10.1002/glia.22937 |
| Citation | Grebing M, et al. (2016) Myelin-specific T cells induce interleukin-1beta expression in lesion-reactive microglial-like cells in zones of axonal degeneration. Glia 64(3):407-24 |
| abstractText | Infiltration of myelin-specific T cells into the central nervous system induces the expression of proinflammatory cytokines in patients with multiple sclerosis (MS). We have previously shown that myelin-specific T cells are recruited into zones of axonal degeneration, where they stimulate lesion-reactive microglia. To gain mechanistic insight, we used RNA microarray analysis to compare the transcript profile in hippocampi from perforant pathway axonal-lesioned mice with and without adoptively transferred myelin-specific T cells 2 days postlesion, when microglia are clearly lesion reactive. Pathway analysis revealed that, among the 1,447 differently expressed transcripts, the interleukin (IL)-1 pathway including all IL-1 receptor ligands was upregulated in the presence of myelin-specific T cells. Quantitative polymerase chain reaction showed increased mRNA levels of IL-1beta, IL-1alpha, and IL-1 receptor antagonist in the T-cell-infiltrated hippocampi from axonal-lesioned mice. In situ hybridization and immunohistochemistry showed a T-cell-enhanced lesion-specific expression of IL-1beta mRNA and protein, respectively, and induction of the apoptosis-associated speck-like protein, ASC, in CD11b(+) cells. Double in situ hybridization showed colocalization of IL-1beta mRNA in a subset of CD11b mRNA(+) cells, of which many were part of cellular doublets or clusters, characteristic of proliferating, lesion-reactive microglia. Double-immunofluorescence showed a T-cell-enhanced colocalization of IL-1beta to CD11b(+) cells, including lesion-reactive CD11b(+) ramified microglia. These results suggest that myelin-specific T cells stimulate lesion-reactive microglial-like cells to produce IL-1beta. These findings are relevant to understand the consequences of T-cell infiltration in white and gray matter lesions in patients with MS. GLIA 2016;64:407-424. |
