The Isolation And Identification Of Fetal Nucleated Red Blood Cells From Maternal Blood

Fetal nucleated red blood cells(FNRBCs) contain the whole human genome and they have a lifespan of about 90 days, and they may be basically disappeared in several days after the infant was born, besides, FNRBCs are rare in the peripheral blood of a normal adult. So FNRBCs were considered to be the preferred candidates for prenatal diagnosis in the future. Since 1893, fetal cells were first detected in the maternal blood, but there was no an effective method to enrich the fetal cells. Because of the scarcity of fetal cells in maternal blood and the deficiency of specific fetal cell marker, they were difficult to retrieve and be used in clinical practice. This study aims to develop a safe and effective non-invasive technique to isolate fetal cells from maternal blood, and which is used for prenatal diagnosis.In the research, we first developed a MDA kit which is suitable for the whole genome amplification of large quantities of cells, and the multiple PCR of housekeeping gene which can identification of amplification efficiency, we also developed a series of rapid methods for the identification of cell source, including the multiple PCR of SRY gene and STR in paternity examination. In practical application, we demonstrated that fetal erythrocytes were present in maternal blood, and then we exploited the cell surface antigen, CD45, CD71 and combining the nucleus dye to developed a method for sorting fetal cells. Through a series of separation and identification, we succeeded at isolation of fetal cells from 30 pregnant women who carried a male fetus, the isolated cell(s) passed the identification of SRY gene and STR test. But we haven’t get a single fetal cell, this against the analysis of fetal genome. In the future, we need to develop a analysis method for mixed cells and we can advantageous to the fetal genome analysis.