Serum soluble interleukin 2 receptor alpha and soluble CD8 levels in patients with gynecological malignancies undergoing radiotherapy.

The phenotype peripheral blood lymphocytes, soluble interleukin 2 receptor alpha (sIL-2R alpha) and soluble CD8 (sCD8) were studied in 30 patients with gynecological malignancies before and after ratiotherapy. The absolute count of CD3+, CD4+, CD8+, CD19+ and CD25+ lymphocytes before treatment was within normal range. The levels of serum sIL-2R alpha and sCD8 were significantly increased before treatment compared to normal controls. After treatment the absolute number of CD3+, CD4+ and CD19+ lymphocyte subsets significantly decreased. The levels of sIL-2 alpha and sCD8 corrected according to absolute lymphocyte count reached normal range. The decrease of tumor mass correlated with the serum levels of sIL-2R alpha and sCD8. Further studies are needed to evaluate the usefulness of these tests in the prognosis and treatment of these diseases. Our study suggests that sIL-2R alpha and sCD8 in our patients probably has not been originating from the proteolytic cleavage of membrane bound receptors from peripheral blood mononuclear cells (PBMC). It can be speculated that sIL-2R alpha and sCD8 originated in these patients from activated tumor-infiltrating lymphocytes or may arise from separate alternatively spliced mRNAs coding for soluble vs. membrane forms.