Introduction

There is evidence that regulatory T cells (Tregs) regulate negatively the activity of the immune system against cancer. Studies showed an increase in the percentage of these cells in peripheral blood of dogs with various types of cancer.

Objectives

The aim of this study was to quantify regulatory T cells in dogs with B-cell multicentric lymphoma.

Methods

For this, 10 healthy animals (control group) and 13 animals with B-cell multicentric lymphoma were used. Animals were evaluated for percentage of Tregs in peripheral blood by flow cytometry (Biller et al., 2007).

Results

Animals of B-cell multicentric lymphoma group showed a higher percentage of Tregs (Foxp3⁺CD4⁺) when compared to control group (18.52 ± 0.50 ± 2.77 x 4.70) with a significant difference between groups (p < 0.0001).

Figure 1. Percentage of Treg in healthy animals (control group) and B-cell multicentric lymphoma group at diagnosis

Conclusion

The elevated percentage of Treg cells in dogs with B-cell lymphoma compared with healthy dogs suggests the possibility that these cells decrease the immune response of host against tumor contributing to development of disease. Thus the use of targeted therapies against Tregs alone or combined with conventional drugs could mean a breakthrough in lymphoma treatment in dogs.