Immunoassay are offered for quantitative determination of human total Bcl-2 in cell lysates. Bcl-2 (B-cell lymphoma 2) is an oncogenic protein that regulates cell death by controlling the permeability of the mitochondrial membrane. It inhibits apoptosis by preventing caspase activity. Bcl-2 expression has been implicated in a wide variety of human cancers including those of the breast, prostate, skin, colon and pancreas. The colorimetric, 96 well plate format precisely measures total Bcl-2 concentration with a range of 18.8 - 1,200 pg/ml in just three hours, making Western blotting obsolete. This assay is non-radioactive, stable and sensitive to 7.6 pg/ml. Each kit comes complete with easy to use, color-coded liquid reagents.