Evaluation of serum interleukin 2 receptor and beta‐2‐microglobulin as prognostic factors for canine lymphoma: A pilot study

Interleukin 2 receptor (IL‐2R) is released from activated T cell lymphocytes and related to proliferation of B cells and T cells. Beta‐2‐microglobulin (B2M) is synthesized from all nucleated cells and constitutes a major histocompatibility complex class I antigen. In human medicine, high concentrations of these two factors have been found to be related to prognosis in aggressive non‐Hodgkin's lymphoma. In this pilot study, we aimed to assess the correlation between the serum concentration of IL‐2R and B2M and the diagnosis and prognosis of canine lymphoma. This study included 8 healthy dogs and 17 dogs with lymphoma. To measure the serum concentration of IL‐2R and B2M, a commercial enzyme‐linked immunosorbent assay was used. In dogs with lymphoma, IL‐2R concentrations were significantly high at the time of diagnosis, but B2M concentrations were not. In relapsed dogs, both IL‐2R and B2M concentrations were significantly higher than those in the control and chemotherapy response groups. When the serum concentrations of IL‐2R and B2M during chemotherapy were monitored in four relapsed dogs, B2M levels were more closely related with relapse. This study demonstrated that serum IL‐2R and B2M concentration can be a diagnostic or prognostic tool for canine lymphoma. Monitoring of serum B2M concentration seems to be useful for predicting relapse.