Flow cytometric analysis is a powerful technique for the single cell assessment of cell surface expression of selected molecules. The major deficiency of flow cytometry has been its relative insensitivity. Only molecules expressed in abundance have been readily observed.
We have developed an enzymatic amplification procedure for the analysis of cell surface molecules by flow cytometry. Transformed and nontransformed cells expressing MHC class I, CD5, CD3, CD4, CD6, CD7, CD34, CD45, MHC class II, Fas ligand, and phosphatidylserine were assessed.
Our enzymatic amplification technology increased the fluorescence signal between 10 and 100-fold for all surface molecules tested.
Enzymatic amplification staining produces a significant enhancement in the resolving power of flow cytometric analysis of cell surface molecules. Using this technique, we have been able to detect the presence of molecules that could not be observed by the standard procedure. Cytometry 40:81–85, 2000 © 2000 Wiley-Liss, Inc.