IL-31 levels in dogs with non-itchy mast cell tumors or lymphoma

Abstract

BACKGROUND: The aim of this study was to compare serum interleukin (IL)-31 concentrations in dogs with lymphoma and mast cell tumours (MCT) without pruritus to those of healthy dogs. HYPOTHESIS/OBJECTIVES: To determine if IL-31 plays a role in tumour pathogenesis and if IL-31 could be a biological marker for disease progression. ANIMALS: Forty-eight healthy dogs and 36 dogs with neoplasia [multicentric lymphoma (14), MCT (15) and cutaneous lymphoma (7)] were included in the study. METHODS AND MATERIALS: Dogs with neoplasia were assigned to three different groups. Group 1 consisted of patients with multicentric lymphoma, which were diagnosed by cytological, histopathological and clonality investigations. Thoracic radiographs, ultrasound examination of the abdominal cavity, and fine-needle aspirates from liver and spleen were used to determine the lymphoma stage Patients with cutaneous lymphoma, diagnosed by cytological and histopathological findings, were included in Group 2. Patients with MCT, diagnosed by cytological and histopathological findings, were included in Group 3. Serum was frozen at -80ºC before measuring the concentration of IL-31 via a Simoa ultra-sensitive, fully automated two-step immunoassay. RESULTS: Serum concentrations of IL-31, regardless of the disease and its staging, were within the normal range in all patients; there was no difference between any of the different tumour groups and healthy dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: IL-31 is not likely to be involved in the pathogenesis of canine MCT or lymphoma without pruritus.