The immunoregulatory effect of CD8+CD28-T lymphocytes in an experimental bone marrow mesenchymal stem cell treatment of autoimmune encephalomyelitis / 中华物理医学与康复杂志

ABSTRACT

Objective To study the immune system regulatory effects of CD8+CD28-regulatory T lymphocytes in an experimental bone marrow mesenchymal stem cell treatment of autoimmune encephalomyelitis.Methods A model of autoimmune encephalomyelitis (EAE) was established in twenty-eight C57BL/6 female mice,6 to 8 weeks old weighing 16 to 20 g using myelinoligodendrocyte glycoprotein 35-55 amino acid peptide (MOG35-55).The mice were randomly divided into a phosphate-buffered solution (PBS) group (n =7),an MSCs-Low group [n =7 which received an injection of 2× 105 mesenchymal stem cells (MSCs)],an MSCs-Med group (n=7,1× 106 MSCs),and an MSCs-High group (n=7,5×106 MSCs).Their clinical condition was then evaluated daily.On the 15th day after the MOG35-55 immunization,the different MSC doses were administered intravenously via the tail.On the 30th day the mice were sacrificed to observe any neuropathology of the spinal cord.At the same time,FACS flow cytometry was used to assay CD8+CD28-T cells in the spleen.Results Compared with the PBS control group,the MSC treatment effectively alleviated illness among the mice by the 15th day after the immunization.The maximum and average disease scores and clinical illness scores had all improved significantly.The medium dosage worked best.Neuropathological analysis showed that the MSC treatment could significantly reduce the invasion of inflammatory cells and minimize demyelination in the spinal cord.Furthermore,the CD8+ CD28-regulatory T cells in the spleens of the MSCtreated animals increased compared with the PBS control group,though the secreted levels of IL-10 showed no obvious difference.Conclusions Treatment with MCSs can promote the recovery of neural function in autoimmune encephalomyelitis,at least in mice.CD8+CD28-regulatory T cells may not be the main effector cells,playing only a synergistic therapeutic role.