Transcription profile of chemokine receptors, cytokines and cytotoxic markers in peripheral blood of dogs with epitheliotropic cutaneous lymphoma

Abstract

Mycosis fungoides (MF) is the most common form of canine epitheliotropic cutaneous lymphoma, which is characterized by the accumulation of neoplastic CD8(+) T cells. Given that multifocal skin lesions are commonly seen in MF, neoplastic lymphocytes may actively migrate into the blood circulation. Cytotoxic T cells with a skin-homing phenotype could be increased in the blood circulation of dogs with MF. Ten dogs with MF and 10 age-matched healthy dogs were included. The transcription levels of chemokine receptors, cytokines and cytotoxic markers in peripheral blood of dogs with MF were quantified by real-time RT-PCR. The dogs with MF had lower transcription levels of chemokine receptors associated with skin homing (CCR4), epitheliotropism (CXCR3), lymph node homing (CCR7), a type-1 cytokine (LT-α) and cytotoxic markers (perforin and granzyme B) in the circulation than healthy control dogs (P < 0.05). The present results suggest that the number of peripheral cytotoxic T cells with a skin-homing phenotype could be decreased in the peripheral blood of dogs with MF, which might be due to the sequestration of cytotoxic T cells in the lesional skin.