A novel kind of multi-core magnetic composite particles, the surfaces of which were respectively mo- dified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71), was prepared. The fetal nucleated red blo...A novel kind of multi-core magnetic composite particles, the surfaces of which were respectively mo- dified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71), was prepared. The fetal nucleated red blood cells(FNRBCs) in the peripheral blood of a gravida were rapidly and effectively enriched and separated by the mo- dified multi-core magnetic composite particles in an external magnetic field. The obtained FNRBCs were used for the identification of the fetal sex by means of fluorescence in situ hybridization(FISH) technique. The results demonstrate that the multi-core magnetic composite particles meet the requirements for the enrichment and speration of FNRBCs with a low concentration and the accuracy of detetion for the diagnosis of fetal sex reached to 95%. Moreover, the obtained FNRBCs were applied to the non-invasive diagnosis of Down syndrome and chromosome 3p21 was de- tected. The above facts indicate that the novel multi-core magnetic composite particles-based method is simple, relia- ble and cost-effective and has opened up vast vistas for the potential application in clinic non-invasive prenatal diag- nosis.展开更多
To find a simple, effective method of isolating fetal cells from maternal peripheral blood for prenatal diagnosis, 45 women were studied with their gestation being 6-14 weeks and age 21- 30 years. The fetal cells wer...To find a simple, effective method of isolating fetal cells from maternal peripheral blood for prenatal diagnosis, 45 women were studied with their gestation being 6-14 weeks and age 21- 30 years. The fetal cells were isolated from maternal blood by using discontinuous density gradient centrifugation. Some of the isolated cells were made smear and counted under the microscope; others were used for predicting fetal sex by PCR amplification of Y chromosome specific DYZ1 gene. The major cells in the upper separation interface were lymphocytes and monocytes, with occasionally seen nucleated red blood cells (NRBC); while those in the middle separation interface were neutrocytes, with NRBC scattering. The ratio of NRBC/nucleated cells was 1. 98±0. 28× 10-5. There was no significant difference between the first and second trimester (P>0. 05). The amount of isolated fetal cells was sufficient for prenatal genetic diagnosis. Male pregnancy was correctly predicted in 10 out of 13 cases. It is concluded that the method of discontinuous density gradient centrifugation was of considerable importance in the development of non-invasive prenatal genetic diagnosis.展开更多
The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for nonin...The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for noninvasive prenatal diagnosis. Single fetal nucleated erythroblasts were isolated from the peripheral blood samples from 51 pregnant women by micromanipulation techniques after density gradient centrifugation. Nested polymerase chain reaction method was used to amplify the SRY gene. It was found that the concordance rate of amplification results with real fetal sex was 82.61 %. The sensitivity and specificity were 80 % and 87.50 % respectively. It was suggested that it is feasible and promising in non invasive prenatal diagnosis to detect fetal nucleated erythroblasts at a single cell level by using micromanipulation techniques.展开更多
In order to search for a more reliable method of sorting fetal nucleated red blood cells (NRBCs) and DNA from maternal peripheral blood and to identify origin of NRBCs and DNA, NRBCs were isolated from peripheral bloo...In order to search for a more reliable method of sorting fetal nucleated red blood cells (NRBCs) and DNA from maternal peripheral blood and to identify origin of NRBCs and DNA, NRBCs were isolated from peripheral blood of 88 pregnant women by density gradient centrifugation and fluorescence activated cell sorter (FACS) respectively. Nested polymerase chain reaction was used to detect normal male SRY gene from blood plasma DNA of 65 pregnant women. The results revealed that fetal NRBCs were found in 14 of 27 maternal samples by density gradient centrifugation. The number of cells was from 1 to 10. Using FACS, CD71 + cells were identified among all 61 samples. The frequency was (0.35±0.25)×10 -2; The detectable rate of the SRY gene of blood plasma DNA from 46 women carrying male fetuses was 65.22 % (30/46). Non-detectable rate for 19 women carrying female fetuses was 94.74 % (18/19). It was concluded that the methods of sorting fetal NRBCs and DNA have already made great progress. The methods for fetal NRBCs and plasma DNA from maternal peripheral blood to diagnose genetic diseases seem to be the best methods of noninvasive prenatal diagnosis.展开更多
文摘A novel kind of multi-core magnetic composite particles, the surfaces of which were respectively mo- dified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71), was prepared. The fetal nucleated red blood cells(FNRBCs) in the peripheral blood of a gravida were rapidly and effectively enriched and separated by the mo- dified multi-core magnetic composite particles in an external magnetic field. The obtained FNRBCs were used for the identification of the fetal sex by means of fluorescence in situ hybridization(FISH) technique. The results demonstrate that the multi-core magnetic composite particles meet the requirements for the enrichment and speration of FNRBCs with a low concentration and the accuracy of detetion for the diagnosis of fetal sex reached to 95%. Moreover, the obtained FNRBCs were applied to the non-invasive diagnosis of Down syndrome and chromosome 3p21 was de- tected. The above facts indicate that the novel multi-core magnetic composite particles-based method is simple, relia- ble and cost-effective and has opened up vast vistas for the potential application in clinic non-invasive prenatal diag- nosis.
文摘To find a simple, effective method of isolating fetal cells from maternal peripheral blood for prenatal diagnosis, 45 women were studied with their gestation being 6-14 weeks and age 21- 30 years. The fetal cells were isolated from maternal blood by using discontinuous density gradient centrifugation. Some of the isolated cells were made smear and counted under the microscope; others were used for predicting fetal sex by PCR amplification of Y chromosome specific DYZ1 gene. The major cells in the upper separation interface were lymphocytes and monocytes, with occasionally seen nucleated red blood cells (NRBC); while those in the middle separation interface were neutrocytes, with NRBC scattering. The ratio of NRBC/nucleated cells was 1. 98±0. 28× 10-5. There was no significant difference between the first and second trimester (P>0. 05). The amount of isolated fetal cells was sufficient for prenatal genetic diagnosis. Male pregnancy was correctly predicted in 10 out of 13 cases. It is concluded that the method of discontinuous density gradient centrifugation was of considerable importance in the development of non-invasive prenatal genetic diagnosis.
基金This project was supported by a grant from Science Foun-dation of Ministry of Public Heath of China (No. 96 .2 - 112 )and a grant from Hubei Provincial National Natural ScienceFoundation(96 J0 6 8)
文摘The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for noninvasive prenatal diagnosis. Single fetal nucleated erythroblasts were isolated from the peripheral blood samples from 51 pregnant women by micromanipulation techniques after density gradient centrifugation. Nested polymerase chain reaction method was used to amplify the SRY gene. It was found that the concordance rate of amplification results with real fetal sex was 82.61 %. The sensitivity and specificity were 80 % and 87.50 % respectively. It was suggested that it is feasible and promising in non invasive prenatal diagnosis to detect fetal nucleated erythroblasts at a single cell level by using micromanipulation techniques.
文摘In order to search for a more reliable method of sorting fetal nucleated red blood cells (NRBCs) and DNA from maternal peripheral blood and to identify origin of NRBCs and DNA, NRBCs were isolated from peripheral blood of 88 pregnant women by density gradient centrifugation and fluorescence activated cell sorter (FACS) respectively. Nested polymerase chain reaction was used to detect normal male SRY gene from blood plasma DNA of 65 pregnant women. The results revealed that fetal NRBCs were found in 14 of 27 maternal samples by density gradient centrifugation. The number of cells was from 1 to 10. Using FACS, CD71 + cells were identified among all 61 samples. The frequency was (0.35±0.25)×10 -2; The detectable rate of the SRY gene of blood plasma DNA from 46 women carrying male fetuses was 65.22 % (30/46). Non-detectable rate for 19 women carrying female fetuses was 94.74 % (18/19). It was concluded that the methods of sorting fetal NRBCs and DNA have already made great progress. The methods for fetal NRBCs and plasma DNA from maternal peripheral blood to diagnose genetic diseases seem to be the best methods of noninvasive prenatal diagnosis.