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Updated: May 31, 2026
Discrimination and Characterization of Heterocellular Populations Using Quantitative Imaging Techniques
Published on: June 30, 2017
Preclinical applications of quantitative imaging cytometry to support drug discovery
David L Krull1, Richard A Peterson
1GlaxoSmithKline, Safety Assessment, Investigative Pathology Laboratory, Research Triangle Park, North Carolina, USA.
Abstract:
Preclinical drug development is actively involved in testing compounds to find cures or to manage the effects of disease, such as diabetes. Animal models, such as the Zucker diabetic fatty (ZDF) rat, are used to measure efficacy of candidate drugs. This animal model was selected because of its clinical and pathological similarities to diabetic human patients. A method using immunofluorescence and laser scanning cytometry (LSC) technology has been used to measure the development of diabetic phenotype in the ZDF rat during a 17-week time course. The expression levels of insulin, glucagon, voltage-dependent anion channel (VDAC), and Ki67 were quantified. Insulin and VDAC expression were reduced in the ZDF animals in comparison to the lean control rats, while no significant change was seen in glucagon and Ki67 expression at week 17. This information is useful in the design of studies to test experimental compounds in this model. Screening drug targets or biomarkers in tissue sections is another important activity in drug development. Tissue microarrays (TMAs) are composed of 60 or more tissue cores from humans or animal models and may contain healthy and/or diseased tissues. Antibodies against target proteins are applied to TMAs using routine immunohistochemical reagents and protocols. The protein expression across the cores, as labeled by immunohistochemistry, is measured using LSC technology. The process provides an efficient and cost-effective method for evaluating multiple targets in a large number of tissue samples. More recently, IHC and LSC have been taken to the next level to quantify biopharmaceutical drug and target co-localization in tissue sections.
Insights
Preclinical drug development utilizes the Zucker diabetic fatty (ZDF) rat model to assess drug efficacy. Researchers quantified protein expression, finding reduced insulin and VDAC levels in ZDF rats, aiding future study designs.
Area of Science:
- Biomedical Research
- Pharmacology
- Diabetology
Background:
- Preclinical drug development investigates compounds for disease management, including diabetes.
- Animal models like the Zucker diabetic fatty (ZDF) rat mimic human diabetic conditions for drug efficacy testing.
Purpose of the Study:
- To evaluate the utility of immunofluorescence and laser scanning cytometry (LSC) for measuring diabetic phenotype development in ZDF rats over 17 weeks.
- To quantify the expression of key proteins (insulin, glucagon, VDAC, Ki67) in ZDF rats compared to lean controls.
Main Methods:
- Utilized immunofluorescence and laser scanning cytometry (LSC) technology for quantitative analysis.
- Monitored ZDF rats over a 17-week period.
- Measured expression levels of insulin, glucagon, voltage-dependent anion channel (VDAC), and Ki67.
Main Results:
- Insulin and VDAC expression levels were significantly reduced in ZDF rats compared to lean controls at 17 weeks.
- No significant changes were observed in glucagon and Ki67 expression levels at week 17.
- Demonstrated the utility of LSC for quantifying protein expression in a diabetic rat model.
Conclusions:
- The ZDF rat model, analyzed by LSC, provides valuable insights for preclinical diabetes drug development.
- Quantification of insulin and VDAC expression can serve as biomarkers for diabetic phenotype in this model.
- This methodology supports efficient screening of drug targets and biomarkers in tissue sections, including tissue microarrays (TMAs).
