Spontaneous extracutaneous systemic mastocytosis in a cynomolgus macaque ()

Z. Zöller Martina , Kaspareit Joachim

A uniform cell population of proliferating mast cells with poor cytoplasmic granularity and few eosinophilic infiltrates was observed in hepatic portal tracts and the cecal submucosa of an adult male cynomolgus macaque () that was part of a drug safety assessment toxicity study. The proliferating mast cells were positive for Giemsa and toluidine blue staining and had strong immunoreactivity for mast cell tryptase and CD68. Considering size, morphology, immunoreactivity and distribution of the lesions a benign proliferative disorder of connective tissue mast cells was diagnosed comparable to that seen in indolent systemic mastocytosis in humans, but lacking associated skin lesions. The finding of visceral mast cell proliferation has to be included in the spontaneous background pathology spectrum of cynomolgus macaques used in toxicological studies.

Mots clés: Cecum; Cynomolgus macaque; Liver; Mast cell proliferation; Mast cell specific tryptase; Visceral mastocytosis

Z. Zöller Martina, Kaspareit Joachim. Spontaneous extracutaneous systemic mastocytosis in a cynomolgus macaque (). Experimental and Toxicologic Pathology, 2010, 62 (4), pp.375. ⟨10.1016/j.etp.2009.05.004⟩. ⟨hal-00598191⟩