Rhesus monkey is a new model of secondary lymphedema in the upper limb

Objective: This study is to establish the rhesus monkey model of lymphedema in the upper limbs, and assess the suitability of this model. Methods: An animal model of lymphedema was established by the combined irradiation and surgical techniques in the upper limbs of these rhesus monkeys. Physical examination, high-resolution MR lymphangiography, bioelectrical impedance analysis (BIA), and immunohistochemical staining were performed to determine the severity of the edema in the upper limbs of the animal model. Results: Our results from physical examination indicated that the rhesus monkey model present with typical appearance and features of lymphedema. MR lymphangiography further demonstrated pathologically modified lymphatic vessels in our rhesus monkey model. BIA revealed increased water content in the upper limb in these rhesus monkeys, which was in line with the pathology of lymphedema. Immunohistochemical staining showed the curvature of the lymphatic vessels in the rhesus monkey model, typical pathological changes in lymphedema. Conclusion: Rhesus monkey lymphedema model provides a more consistent background to elucidate the pathophysiology of the disease. This new model would help to increase our understanding of acquired upper limb lymphedema, and promote the development of new treatments for this intractable disorder.