Flow Cytometry in the Preclinical Development of Biopharmaceuticals

Abstract

Novel biomarkers are often required in the preclinical development of biopharmaceuticals in order to characterize pharmacologic and toxicologic effects and to establish pharmacodynamic and pharmacokinetic relationships. Flow cytometry is uniquely suited for measurement of these biomarkers. Large numbers of single cells in a heterogeneous population can be rapidly identified and characterized with high accuracy and reproducibility. Cells are not damaged by the detection system and can be subsequently sorted for further morphologic or functional analysis. The availability of clinical instruments and a wide range of fluorescent probes have made this technology applicable for use in toxicologic clinical pathology. Flow cytometry has played an integral role in the development of a monoclonal antibody to human CD4 (keliximab, IDEC-CE9.1, SB 210396). Lymphocyte subset analysis and assays for expression, coating, and modulation of human CD4 were used for sequential assessment of the pharmacologic activity of keliximab in transgenic mice expressing human CD4.

Keywords

Flow cytometry biopharmaceuticals pharmacology toxicology drug development animal

References

Anderson D. , Chambers K. , Hanna N. , Leonard J. , Reff M. , Newman R. , Baldoni J. , Dunleavy D. , Reddy M. , Sweet R. , and Truneh A. (1997). A primatized Mab to human CD4 causes receptor modulation, without marked reduction in CD4+ T cells in chimpanzees: In vitro and in vivo characterization of a Mab (IDEC-CE9.1) to human CD4. Clin. Immunol. Immunopathol. 84: 73-84.

Givan AL (1992). Flow Cytometry: First Principles. Wiley-Liss, New York.

Killeen N. , Sawada S. , and Littman DR (1993). Regulated expression of human CD4 rescues helper T cell development in mice lacking expression of endogenous CD4. EMBO J. 12: 1547-1553.

McCoy JP (1994). Basic principles in clinical flow cytometry. In: Flow Cytometry in Clinical Diagnosis, DF Keren et al (eds). American Society of Clinical Pathologists Press, Chicago, pp. 26-55.

Morel P. , Vincent C. , Cordier G. , Panaye G. , Carosella E. , and Revillard JP (1990). Anti-CD4 monoclonal antibody administration in renal transplanted patients. Clin. Immunol. Immunopathol. 56: 311—322.

Shizuru JA , Gregory AK , Chao CT and Fathman CG (1987). Islet allograft survival after a single course of treatment with antibody to L3T4. Science 237: 278-280.

Waldor MK , Sriram S. , Hardy R. , Herzenberg L. , Lanier L. , Lim M. , and Steinman L. (1985). Reversal of experimental allergic encephalomyelitis with monoclonal antibody to a T-cell subset marker. Science 227: 415-417.

Weingand K. , Brown G. , Hall R. , Davies D. , Gossett K. , Neptun D. , Waner T. , Matsuzawa T. , Salemink P. , Froelke W. , Provost JP , Dal Negro G. , Batchelor J. , Nomura M. , Groetsch H. , Boink A. , Kimball J. , Woodman D. , York M. , Fabianson-Johnson E. , Lupart M. , and Melloni E. (1996). Harmonization of animal clinical pathology testing in toxicity and safety studies. Fundam. Appl. Toxicol. 29:198—201.