ABSTRACT
A notable degree of research attention is being focused on the use of fetal cells enriched from the blood of pregnant women as a non-invasive means of prenatal diagnosis. By using magnetic activated cells sorting (MACS) and fluorescence in situ hybridization (FISH), we have examined the efficacy of enriched fetal cells in determining fetal sex. An unexpected finding of this investigation was that the sensitivity of this analysis was influenced by the anticoagulant used to treat the maternal blood samples. As such, samples treated with heparin showed significantly lower detection rates than samples chelated with EDTA.
Subject(s)
Anticoagulants/pharmacology , Blood Cells/drug effects , Fetus/cytology , In Situ Hybridization, Fluorescence , Blood Cells/cytology , Blood Specimen Collection/methods , Cell Death , Edetic Acid/pharmacology , Female , Heparin/pharmacology , Humans , Immunomagnetic Separation , Male , Pregnancy , Sensitivity and SpecificityABSTRACT
OBJECTIVE: The efficiency of two protocols for the enrichment of fetal cells from the blood of pregnant women was compared: a triple density gradient followed by twin magnetic separations (method A) versus a single density gradient and single magnetic separation (method B). STUDY DESIGN: Blood samples were obtained from women prior to undergoing an invasive procedure. The processed samples, 87 by method A and 332 by method B, were examined for the presence of male cells by fluorescence in situ hybridisation. RESULTS: The simpler protocol was found to be superior. The most critical component, however, is the ability of the reader to correctly evaluate the sample, where we observed large variations, with reader B attaining a sensitivity of 82.61% with a corresponding specificity of 86.96%. CONCLUSION: A simpler enrichment protocol can be used from smaller blood samples to attain detection efficiencies which are similar to or superior to current noninvasive methods.
