Flow Cytometry Applications for Immune Monitoring

Vernon C. Maino, BD Biosciences, San Jose, CA, USA

Recent developments in immunosuppressant drug therapy and a number of related advances in patient management have contributed in a major way to both the survival of transplant patients and the prolongation of the half-lives of transplanted organs. Despite these advances, treatment related toxicities still negatively impact standard of care and have inspired new interest in developing immune monitoring assays to better identify biomarkers of immune tolerance and patient-specific variations in response to treatment to better manage transplant patients. Flow cytometry is a recognized immune monitoring platform for the analysis of complex multi-parametric cellular assays. The translation of cellular assays for the detection of biomarkers to the clinic is an active area of research.

The unique capability of flow cytometry to perform multiparameter cell analysis (i.e., more than one measurable feature per cell) provides the basis for most cell analysis applications. The advent of gene-expression technologies and the availability of new monoclonal antibodies and fluorochromes have enabled more sophisticated multiparameter analyses.Recently, newer applications that enable detection of intracellular functional markers, for example, cytokines and cell-signaling molecules have benefited from multicolor flow cytometry in the dissection of complex cellular functions.

Now that flow cytometry can analyze multiple parameters (up to 15 and beyond) and also measure soluble factors, these instruments will generate a colossal amount of data from single cells and/or very small samples.In addition, recent advances in supporting technologies such as cell bar-coding,plate loaders, preconfigured lyophilized reagents (e.g., BD Lyoplate), cell-surface quantitation (e.g., the BD Quantibrite™ fluorescence quantification system), and new developments in analysis software and data management are enabling a powerful, data-rich platform with enhanced automation capabilities. Advances in instrument setup, calibration, and automated compensation are rapidly being integrated into contemporary instrument software packages. These improvements will contribute to the evolving need to standardize newer, more complex multicolor flow cytometry applications as they begin to demonstrate utility in immune monitoring and diagnostic assays.

In this presentation I will review some emerging applications in flow cytometry that we believe will impact the future of this platform in immune monitoring and biomarker discovery.In addition, I will comment on how multicolor flow cytometry might become more relevant to the emerging concepts in systems biology.