Companion animals: Translational scientist's new best friends

Abstract

Knowledge and resources derived from veterinary medicine represent an underused resource that could serve as a bridge between data obtained from diseases models in laboratory animals and human clinical trials. Naturally occurring disease in companion animals that display the defining attributes of similar, if not identical, diseases in humans hold promise for providing predictive proof of concept in the evaluation of new therapeutics and devices. Here we outline comparative aspects of naturally occurring diseases in companion animals and discuss their current uses in translational medicine, benefits, and shortcomings. Last, we envision how these natural models of disease might ultimately decrease the failure rate in human clinical trials and accelerate the delivery of effective treatments to the human clinical market.

Fig. 1. Companion animal trials

Shown (highlighted in red) is the proposed role of veterinary clinical trials as predictors of human efficacy studies. Veterinary clinical trials could serve as a bridge between preclinical and clinical studies, with the goal of reducing the failure rates of human clinical trials and accelerating approval of new therapeutics. R&D, research and development.

Fig. 2. Clinical specialization in veterinary medicine

The numbers of board-certified veterinary specialists and specialty organizations since 1950 (A) and the current distribution of veterinary specialists (B) are depicted. In 1951, the American College of Veterinary Pathologists was recognized as the first specialty organization. Since then, the American Veterinary Medical Association’s, American Board of Veterinary Specialties has given accreditation to 21 additional specialty organizations. The most recent addition, the American College of Animal Welfare, was accredited in 2012. Congruous with the expansion of recognized specialties, the numbers of board-certified specialists is also on the rise. A small community of 389 veterinary specialists in the year 1967 has increased exponentially throughout the intervening years. At the time of this writing, there are more than 11,000 active board-certified veterinary specialists.

Fig. 3. Behaving like animals

Here, we show similar clinical findings in veterinary and human patients with related naturally occurring diseases. Histologic photomicrographs (H&E) from a dog (A) and a human (a) with glioblastoma depict similar morphological features, including vascular proliferation. Close-up images of a dog (B) and a human (b) eye with KCS depict ocular surface changes. A computed tomographic three-dimensional reconstruction image of a dog (C) that received mandibular reconstruction using rh-BMP2 infused in a scaffold and a human (c) who has undergone mandibular reconstruction using autologous bone grafting. An echocardiogram from a cat (D) and a human (d) with hypertrophic cardiomyopathy demonstrates concentric hypertrophy of the left ventricle characterized by thickening of the left ventricular walls with decreased ventricular volume. A colonoscopic image from a dog (E) and a human (e) with inflammatory bowel disease demonstrates colonic inflammation, hemorrhage, and ulceration. A contrast-enhanced magnetic resonance myelogram in a dog (F) and a human (f) with cervical spondylomyelopathy depicts vertebral canal stenosis (white arrows). An arthroscopic image of a torn cranial cruciate ligament in a dog (G) and a torn anterior cruciate ligament in a knee of a human (g) reveals associated arthritic changes. Ultrasonographic images of a superficial digital flexor tendon lesion in a horse (H) and Achilles tendonitis in a human (h) demonstrate similar core lesions.