In vitro maturation potential of monocyte-derived dendritic cells is impaired in patients with spinal cord injury: a case-control study

OBJECTIVE: To determine whether the T-cell reactivity and maturation potential of dendritic cells are impaired in subjects with spinal cord injury (SCI). DESIGN: Cross-sectional, case-control study. SETTING: University hospital in Taiwan. PARTICIPANTS: Thirty male SCI subjects, including 14 with paraplegia and 16 with tetraplegia, and 30 age- and sex-matched healthy controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: CD4+ and CD8+ T-cell reactivity was assessed by lymphoproliferative response (LPR) and CD69 expression in response to stimulation with antigens, anti-CD3 monoclonal antibody, and mitogen. Dendritic cell maturation potential was assessed by phenotypic (CD80 and CD83 expression in stimulated monocyte-derived dendritic cells) and functional (the LPR of alloreactive T cells in mixed leukocyte reactions) analysis. RESULTS: The potential of phenotypic and functional maturation of dendritic cells of subjects with SCI was significantly impaired compared with healthy controls, and that potential was worse for tetraplegic patients than for paraplegic patients. However, no significant difference was found in T-cell responses of CD4+ and CD8+ subsets between subjects with SCI and healthy controls. CONCLUSIONS: Impaired maturation potential of dendritic cells is a novel defect in innate immunity in people with SCI.