Introduction Previous studies have shown the existence of either cellular or humoral MBP-reactive elements up to 5 years after spinal cord injury (SCI), but not the presence of both after 10 years. Materials and methods Twelve SCI patients, with more than 10 years of evolution, and 18 healthy blood donors were studied. Lymphocyte proliferation (colorimetricBrdU ELISA assay) and antibody titers against MBP (ELISA Human IgG MBP-specific assay) were assessed. Results SCI patients presented a significant T-cell proliferation against MBP (lymphocyte proliferation index: 3.7 ± 1.5, mean ± SD) compared to control individuals (0.7 ± 0.3; P \ 0.001). Humoral response analysis yielded a significant difference (P \ 0.0001) between the antibody titers of controls and SCI patients. A significant correlation between cellular and humoral responses was observed. Finally, patients with an ASIA B presented the highest immune responses. Conclusion This work demonstrates, for the first time, the existence of both cellular and humoral responses against MBP in the chronic stages ([10 years) of injury.