An Immunohistochemical Study of Rat Sciatic Nerve Macrophages after Injury and Subperineural Transplantation of Mesenchymal Stem Cells

The dynamics of post-traumatic (ligation, 40 s) sciatic nerveWallerian degeneration was studied in Wistar-Kyoto rats with thefocus on the density of Iba-1(+) macrophagesand the state of Luxol Fast Blue-stained myelin fibers in the distalnerve segment at different times after injury. In part of rats,bone marrow mesenchymal stem cells (MSCs) derived from the samerat strain were transplanted subperineurally. It was shown thata highest distribution density of macrophages in the sciatic nervedistal segment was observed 7 days after surgery. Cell therapy ledboth to a decrease in the number of macrophages during this periodand to a delayed demyelination of injured nerve fibers. Sixty daysafter surgery, the macrophage population density and the numberof remyelinated nerve fibers in the distal nerve segment were statisticallyindistinguishable in control (ligated) and experimental (ligatedand MSC transplanted) animals. The molecular mechanisms underlyingthe early post-injury recovery processes require further investigation.