OncoImmunin, Inc. has designed, synthesized, validated, and
patented a new class of cell permeable fluorogenic protease substrates.
Unique aspects of these probes are: (1) their ability to cross intact cell
membranes enables measurement of intracellular protease activities in live
cells, (2) incorporation of amino acid sequence information from both sides
of protease cleavage sites. i.e. P and P' residues, up to a total of 10 amino
acid residues, provides complete protease recognition sequences, (3)
conformation of substrates' peptide moieties assume loop or extended beta
sheet conformations resulting in substrates retaining protease in vivo
specificity and (4) the choice of fluorophores permits
simultaneous measurement of multiple proteolytic activities in biologic
OncoImmunin, Inc.'s novel and unique class of fluorogenic apoptosis assay substrates for
the detection and measurement of caspase 3 and caspase 3-like activities in cells (for other apoptosis-specific
fluorogenic substrates [CaspaLux®
family], see below). The presence of the amino acid sequence of DEVDGI allows one
to determine the apoptosis specific, intracellular caspase-3 (CPP32) and caspase-3-like
activities by flow cytometry or fluorescence microscopy. By judicious choice of
fluorophores, either green or red fluorescence (or under license, far red) may be observed. Cells
are neither permeabilized nor fixed. The principle
used in the design of these apoptosis reagents was derived from exciton theory.
PhiPhiLux® instructions are
(click icon for download):
Flow cytometry data from apoptosis studies
The range in sensitivity between a
T-Cell leukemic (Jurkat cell, left below) and a
Burkitt's lymphoma (SKW 6.4, right below) line to different apoptogens is exemplified by
SKW6.4 ± αFas Ab
+ PhiPhilux®- G1D2
+ αFas Ab
Treatment of a
breast tumor cell (231-01) line with TRAIL:
Activation of caspase 8 (red = cleavage of CaspaLux®
No other protease assay is like it!
Specific- peptide sequence is selected to match the desired protease Sensitive- this is fluorescence, after all! Broadly applicable - works not only for clear solutions but also cell
A PhiPhiLux® kit can be purchased using
a Visa/MasterCard credit card by phone, FAX, or e-mail.
Call for special introductory prices.
PhiPhiLux® is US patented; additional US patent
and PCT applications are pending.
With OncoImmunin's CaspaLux ®
substrates, the activities of caspases-1,6,8 and -9 can be measured. Moreover,
by combining the 5 different substrates in complementary colors, multiple
caspase activity can be determined simultaneously in live cells by both flow
cytometry and microscopy. A high throughput assay is also available.
substrates for caspases are available in two colors: (click on icon to download protocol)