Relationship between regulatory and type 1 T cells in dogs with oral malignant melanoma
Version of Record online: 20 NOV 2009
© 2009 The Societies and Blackwell Publishing Asia Pty Ltd
Microbiology and Immunology
Volume 54, Issue 3, pages 152–159, March 2010
How to Cite
Horiuchi, Y., Tominaga, M., Ichikawa, M., Yamashita, M., Okano, K., Jikumaru, Y., Nariai, Y., Nakajima, Y., Kuwabara, M. and Yukawa, M. (2010), Relationship between regulatory and type 1 T cells in dogs with oral malignant melanoma. Microbiology and Immunology, 54: 152–159. doi: 10.1111/j.1348-0421.2009.00194.x
- Issue online: 25 FEB 2010
- Version of Record online: 20 NOV 2009
- Received 28 September 2009; revised 27 October 2009; accepted 5 November 2009.
- type 1 T cells
Recent data suggest a decreased prevalence of IFN-γ-producing T lymphocytes (Type 1 T cells) in tumor-bearing hosts. Moreover, it has been reported that Treg have a strong impact on the activation and proliferation of CD4 (+) and CD8 (+) lymphocytes; however, no previous reports have described the relationship between Treg and the progression of tumor, or Type 1 T cell populations in dogs with malignant tumor. In this study, the percentage of Treg, Th1, and Tc1 in the peripheral blood of dogs with oral malignant melanoma and healthy dogs was measured and compared. Although the percentages of Th1 and Tc1 in dogs with oral malignant melanoma were less than those in healthy dogs (Th1: P < 0.01, Tc1: P < 0.05), the percentage of Treg was increased (P < 0.01). A significant inverse correlation between the percentage of Tc1 and the clinical tumor stage (P < 0.01), and a significant correlation between that of Treg and the clinical tumor stage (P < 0.001) was found. Moreover, there was a significant inverse correlation between the percentages of Treg and Th1 (P < 0.05) or Tc1 (P < 0.001). In conclusion, the percentage of Treg increases with the tumor stage in the peripheral blood of dogs with oral malignant melanoma. In dogs, Treg appears to suppress Type 1 immunity, which may be responsible for anti-tumor responses.