To Compare The Transplantation Efficiency Of MrBMT And TBMT In Peripheral Tissues

ObjectiveThis work intends to explore the effective cell replacement strategy of tissue resident macrophages in peripheral organs,and clarify the replacement efficiency of peripheral tissue resident macrophages microglia replacement by bone marrow transplantation.MethodsThe tBMT strategy was to give adult recipient mice C57BL/6J acid water and neomycin for 14 days,until receiving by 9 Gy X ray irradiation.After the treatment,the recipient mice were administrated with GFP labeled 1x10~7bone marrow cells from the donor mice through tail vein injection.The mrBMT strategy was to treat adult recipient mice C57BL/6J with PLX5622 for 2 weeks,at the same time,they were given acid water and neomycin,and then received9 Gy X ray irradiation.On the same day,the recipient mice were injected with GFP labeled 1x10~7bone marrow cells from the donor mice through tail vein injection.After that,the mice were administrated with control diet for 30 days to remove the inhibition of colony stimulating factor 1 receptor.In the following,immunofluorescence staining was used to evaluate the efficiency of cell replacement in liver,kidney,spleen and lung.ResultsAfter two weeks administration of PLX5622,consistent with previous results,most of microglia in the brain have been depleted.For the peripheral organs,there is different depletion efficiency in the four organs about tissue resident macrophages,including liver,kidney,lung and spleen.Through the mrBMT and tBMT,the macrophages in the peripheral organs got the high replacement efficiency actually,and the two methods acquire similar efficient replacement.In addition,the cell morphology of the cells derived from allografted bone marrow cells was changed.The cell bodies derived from allografted bone marrow cells are smaller than those of resident macrophages.ConclusionsPeripheral tissues achieved certain depletion efficiency after administration of PLX5622.In the peripheral organs,including liver,kidney,spleen and lung,the tissue resident macrophages have a higher efficiency of cell replacement,as same as in the brain.And there is a similar efficiency of cell replacement between tBMT and mrBMT in the four organs tested.Moreover,the cell morphology of allografted bone marrow cells is smaller than the tissue resident macrophage in the organs,and the cells possessed less branch.