Rob Palmer- >In my lab we are having a friendly discussion on the derivation and >use of the term "multiplex". What does this term mean and under >what conditions is its use appropriate? For example, does the use >of FITC/TRITC/Cy5 qualify as a "multiplex" application? If so, I >would counter that this used to be called, appropriately, >"multicolor" so I am not sure why replacement of that previously >valid descriptor with the vague (?) term "multiplex" is >desirable. How about the use of several flavors of quantum >dots? This application seems to garner the modifier "multiplex" on >a frequent basis. When and how is this different than "multicolor"? >Thanks for the scientific lingo lesson :) :)! "Multiplex" is an adjective typically used to describe bead or cellular assays in which the number of populations identified and characterized is greater than the number of parameters measured. For example, beads labeled with different intensities of one or two dyes can be used to do assays for many different bound ligands in a single specimen tube, using as many different detecting reagents as there are ligands, but labeling all the detecting reagents with the same label. In the Luminex 100 system, two red-excited dyes are used to "color code" as many as 100 different classes of beads, with the assay readout in each case based on phycoerythrin fluorescence excited by a green laser. It was shown by Paul Horan et al many years ago that a similar approach could be used with cells; mixing several different fluorescein- and phycoerythrin-labeled antibodies in different proportions allowed the identification of five or more subsets of peripheral blood leukocytes using only two-color fluorescence. Quantum dots are particularly appropriate for highly multiplexed bead labeling because emission in spectral ranges from green to near-IR can be well excited using a single violet or UV source. Standard FITC/TRITC/Cy5 mixes (i.e., one antibody with each label) would not generally be described as "multiplex." -HowardReceived on Mon May 22 12:58:00 2006
This archive was generated by hypermail 2.1.8 : Wed May 24 2006 - 04:12:03 EDT
