| 摘要 |
<p>A method for isolating trophoblast cells in a sample of or derived from maternal blood by (i) optionally removing or lysing erythrocytes, such as by gradient separation from the sample; (ii) contacting the sample with a reagent that is reactive to produce a detectable response with an intracellular enzyme that is present in trophoblasts but not present in maternal blood cells; (iii) identifying trophoblasts by observing the detectable response; and (iv) isolating the trophoblasts from platelets and other cells in the sample. Where the enzyme is P450scc, the preferred reagent is 22-phenoxazonoxy-5-cholene-3β-ol and the response is fluorescence. Where the enzyme is 3β-HSD the reagent is preferably nitroblue tetrazolium with NAD+ in the presence of a 3β-hydroxy-Δ5-steroid substrate and the response is colorimetric.</p> |
