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Updated: Aug 10, 2026
Digestion of Whole Mouse Eyes for Multi-Parameter Flow Cytometric Analysis of Mononuclear Phagocytes
Published on: June 17, 2020
Incidental mononuclear cell infiltrate in the uvea of cynomolgus monkeys
Dinesh P Sinha1, Mark E Cartwright, Robert C Johnson
1Department of Drug Safety and Metabolism, Schering-Plough Research Institute, Lafayette, New Jersey 07848, USA. dineshwar.sinha@spcorp.com
Abstract:
Mononuclear cell infiltrate (MCI) in the uvea was observed in naïve, untreated (control group) cynomolgus monkeys in approximately 25% of drug safety evaluation studies. The total incidence of MCI in the choroid and the ciliary body was 29% of 342 males and 25% of 306 female monkeys. In the studies in which MCI was present in the ciliary body or choroid, the incidence was as high as 75%. There were no other ocular histopathologic findings in these monkeys. All monkeys were clinically healthy and the eyes were not remarkable when examined ophthalmoscopically.
Insights
Mononuclear cell infiltrate (MCI) was found in the eyes of untreated monkeys during drug safety studies. This finding occurred in about 25% of studies, with higher incidence in specific eye tissues.
Area of Science:
- Veterinary Ophthalmology
- Toxicology
- Primate Research
Background:
- Mononuclear cell infiltrate (MCI) is a potential finding in ocular tissues.
- Naïve, untreated cynomolgus monkeys serve as controls in drug safety evaluations.
Purpose of the Study:
- To report the incidence and characteristics of MCI in the uvea of control cynomolgus monkeys.
- To establish a baseline for ocular findings in preclinical drug safety studies.
Main Methods:
- Histopathological examination of ocular tissues from control cynomolgus monkeys.
- Analysis of incidence data for MCI in the uvea, choroid, and ciliary body.
- Correlation of MCI findings with ophthalmoscopic examinations.
Main Results:
- MCI was observed in approximately 25% of drug safety evaluation studies in naïve, untreated cynomolgus monkeys.
- The overall incidence of MCI in the choroid and ciliary body was 29% in males and 25% in females.
- When present, MCI incidence in the ciliary body or choroid reached up to 75% in affected studies.
- No other ocular histopathological findings or clinical abnormalities were noted.
Conclusions:
- MCI in the uvea is an incidental finding in a subset of control cynomolgus monkeys.
- This finding does not appear to be associated with clinical health or other ocular pathologies.
- Understanding the incidence of MCI is crucial for interpreting ocular findings in non-human primate drug safety studies.
