In our primate center, by continuous investigation over 25 years, we have found several spontaneous disorders in monkey colonies. Moreover, we also found that those several age-related or congenital disorders were quite similar to human diseases.
Then those spontaneous animal models can enable us to investigate the mechanism of age-related or congenital diseases, and it also contribute to establishment of therapy.
Sexually mature cynomolgus monkeys show menstrual cycles and menopause similar to those in humans. Bone mass and density are therefore measured to determine post-menopausal osteoporosis and consequently to establish prevention or treatment methods for osteoporosis in humans.
Some monkeys in our breeding colony showed type II diabetes. Progression of the symptoms of this disease was similar to that in humans. As shown in the figure, a diabetic gradually became obese over several years. Then, suddenly they lost weight rapidly, and at the same time their blood glucose levels significantly increased.
We extracted cardiac diseases that ventricular septal defects, double chambered right ventricle, valvular diseases, endocarditis and cardiomyopathy in cynomolgus breeding colony. This is the first case of muscular ventricular septal defect in a cynomolgus monkey. Turbulent blood inflow into the right ventricle through the muscular part of the ventricular septum (arrow) was observed in the short-axis view by echocardiography. [Contemp Top Lab Anim Sci. 2005;44:26-28.]
In aged cynomolgus monkey brains, we can find spontaneous senile plaque formation: one of the major histopathological features in Alzheimer’s disease. Thus cynomolgus monkey is considered as an useful animal model for Alzheimer’s disease and other againg-causative neurodegenerative disorders.
We found familial macular degeneration in cynomolgus monkeys, and maintain that strain in our primate center. Macula lutea is degenerated and becomes unclear in affected eye (upper) compared to normal eye (below).
Endometriosis is often found in the cynomolgus breeding colony. Endometriosis is the most severe diseases in obstetrics because of typically present a chronic pain and infertility. This figure shows endometriomas that have classic characteristics on ultrasound.
Some monkeys showed hyperlipemia even in our strict nutritionally controlled colony. Such monkeys tended to belong to a certain family line. An obese monkey and lacteal serum collected from this monkey are shown in this figure.
|Development of animal model by using nonhuman primates|
|Even today, although biomedical techniques have been well improved, it is still unknown that the onsets and the pathology of emerging infectious diseases or aging-causative disorders, and it is an urgent mission to establish preventive and therapeutic tools such as vaccines, drugs, and techniques for those diseases. Since there are many pathogens that are infected with only primates, it is necessary to use primate animal models for investigating pathologies or evaluating drug developments. In our primate center, we are working on the research aiming for the establishment of primate animal models and applied investigations by using them.
Hepatitis C virus
Hemodyscrasia (Hematopoietic disorders)
Tsukuba Primate Research Center, National Institute of Biomedical Innovation