Intracellular Expression of Neurotrophic Factors in Mononuclear Cells of Cord Blood and G-CSF-Mobilized Peripheral Blood As a Potential Source for Cellular Therapy

Purpose: To investigate a possible therapeutic mechanism for cell therapy in the field of neurological disorders using mobilized peripheral blood mononuclear cells (mPBMCs), we compared the expression of inflammatory cytokines and neurotrophic factors in PBMCs and mPBMCs from children with cerebral palsy (CP) to those from healthy adult donors and to cord blood (CB) donated from healthy newborns.

Methods: We evaluated the intracellular expression of neurotrophic factors and inflammatory cytokines in PBMCs and mPBMCs from 14 CP children and 14 healthy adult volunteer donors as well as CB mononuclear cells (CB-MNCs) donated from healthy newborns. For mPBMC, granulocyte colony stimulating factor (G-CSF, 10μg/kg/day) was administered subcutaneously for five consecutive days, and apheresis was performed on the fifth day to collect mPBMC via a central venous catheter. Both PBMC collected prior to G-CSF administration and apheresed mPBMC were cryopreserved. We performed flow cytometric analysis with intracellular staining for various cytokines after thawing PBMCs and mPBMCs as well as CBs.

Results: No significant differences in expression of neurotrophic factors were found between PBMC and mPBMC. However, in cells from CP children, the expression of IL-6 was significantly increased in mPBMC as compared to PBMC, and IL-3 was significantly decreased in mPBMC as compared to PBMC. In healthy adults, the expression of both IL-1β and IL-6 were significantly increased in mPBMC as compared to PBMC. The expression of BDNF in mPBMC from CP children was significantly higher than in CB or mPBMC from healthy adults. The expression of G-CSF in mPBMC from CP children was comparable to that in CB but significantly higher than in mPBMC from healthy adults. Lower expression of IL-1β, IL-3, and IL-6 and higher expression of IL-8 and IL-9 was observed from CB and mPBMCs from CP children rather than in healthy adults. Lower expression of IL-1β, and higher expression of IL-8 was observed from mPBMCs from CP children rather than in healthy adults.

Conclusion: The altered expression of neurotrophic factors and anti-inflammatory cytokines in mPBMC in CP children and CB from healthy children could provide a new potential source for cellular therapy for individuals with neurologic diseases.