New Reagent Kits Deliver Probes and Antibodies into Cells

PerFix-Expose and PerFix-nc, innovative new reagent kits for intracellular staining from Beckman Coulter Life Sciences, minimise sample manipulation for a streamlined workflow that delivers high quality results. Developed for use on Beckman Coulter’s Gallios and Navios series flow cytometers and compatible with all Beckman Coulter Life Sciences’ fluorochromes, the kits enable a clear focus on the cytoplasmic and nuclear compartments of the cell.

PerFix-Expose (phospho-epitope exposure kit) helps scientists identify and explore complex intracellular signalling pathways disrupted by cancer and other diseases.  It allows fluorochrome-coupled antibodies and other probes to enter into cells, their nuclei and other cell compartments, where they bind to proteins relevant to signalling pathways that have been disrupted by disease.

Cell fixation is accomplished using a cross-linking agent, while permeabilisation of white blood cells and lysis of red blood cells is achieved using a detergent.  A denaturing agent ‘unmasks’ proteins bound to other proteins or DNA.

Beckman Coulter researchers developed the kit for use with whole blood, bone marrow or other fluids containing blood.  Samples are fixed in small test tubes or deep-well microplates and the reagent is mixed with the cells.  The kit can be used to study a variety of other intracellular and intranuclear antigens.

With PerFix-nc (no centrifugation), researchers can perform concomitant surface and intracellular staining for flow cytometry to take advantage of a new approach that provides easy access to the inside of human leucocytes. 

Analysis of multiple intracellular epitopes, or multiple intracellular markers along with cell surface markers, is accomplished by straightforward fixation, permeabilisation and staining of leucocytes from peripheral whole blood, together with erythrocyte lysis.

The preparation is performed at room temperature, without the requirement for wash or centrifugation steps, and can be performed manually or automated on workstations such as the Beckman Coulter Life Sciences Biomek platform.

PerFix-nc kit quality is characterised by mean fluorescence intensities and consistent performance in repeatability studies, as demonstrated by levels of cell recovery.  The kit offers an original and powerful leucocyte permeabilisation method followed by an optimised fixation step in a process that involves only 15 minutes of hands-on user time.