Flow cytometry complexes

While it is true that microarray technology is gearing up for proteomics, it is perhaps still too early to predict what role microarrays will ultimately play. Proteins are much more complex molecules than nucleic acids and the suggestion has been made that additional tools and approaches will be needed. Microfluidic devices (electrophoresis, flow cytometry) with miniaturized detectors may also be applicable. 

As indicated in Chapter 33, flow cytometry has developed rapidly to provide a powerful means of characterizing complex cell populations, both in terms of quantitative analysis of functional cell-associated molecules, and, as is considered here in more detail, the simultaneous analysis of combinations of markers that can be used to identify functional subpopulations of cells. Many of the considerations discussed in the previous chapter are relevant, but issues particularly pertinent to this type of analysis relate to the independence of the markers used, both at the level of the labeling process and at the level of cytometric analysis. 

Prosperi, E, Stivala, N. A., Sala, E., Scovassi, A. I., and Bianchi, L (1993) Proliferating cell nuclear antigen complex formation induced by ultraviolet irradiation in human quiescent fibroblasts as detected by lmmunostaming and flow cytometry Exp Cell Res 205, 320-325. 

Wu, Y., Buranda, T., Simons, P. C., Lopez, G. P., Mclntire, W. E., Garrison, J. C., Prossnitz, E. R., and Sklar, L. A. (2007a). Rapid mix flow cytometry measurements of subsecond regulation of G protein-coupled receptor ternary complex dynamics by guanine nucleotides. Anal. Biochem. In press. 

Fig. 9 PCI-induced transfection utilizing branched and linear PEI as vector. HT116 colon carcinoma cells were treated with AlPcS (20 (tg/mL) for 18 h followed by a 4-h incubation with an plasmid encoding EGFP and complexed with 25 kDa branched or 22 kDa linear PEI at an N P ratio of 4 before light exposure. EGFP expression was measure by flow cytometry 2 days later. The photochemical treatment caused 40-60% cytotoxicity...

I said at the beginning of this book that flow cytometry is currently moving in two directions at once Technological advances provide, in one direction, increasingly rapid, sensitive, complex, but precarious analysis and, in the other direction, increasingly stable, fool-proof, and automated capabilities. Thirty years ago, all flow cytometry was at the complex, but precarious level of development. Now, many of those early precarious developments have been incorporated into routine cytometers, and new techniques are appearing in research instruments. Over the next few years, this progression will continue ... 

Heath Robinson device W. Heath Robinson (1872-1944) was an English humorous artist. A Heath Robinson device is the English term for a complex instrument that looks as if it had been designed by a committee. A Heath Robinson device usually works well but may be held together by chewing gum and string. In the context of state-of-the art flow cytometry, this term requires no further explanation. See also Rube Goldberg device. 

Probe Probe is a general term used, in flow cytometry, to refer to any chemical that fluoresces when it reacts or complexes with a specific class of molecules and therefore can be used to assay that molecule quantitatively. Propidium iodide and acridine orange are probes for nucleic acid because they complex specifically with nucleic acids and fluoresce brightly when they have... 

---