Interleukin-2 alterations in the immune status of patients with mammary neoplasm

Immune control is achieved by the balance between tumour reduction mechanisms and the "immunological creeping" phenomenon. The purpose of this study was to look into the alterations of the immune effector component in the case of mammary tumours. The study included 42 cases of women with a clinical diagnosis of mammary tumour, initially referred for surgery, with a mean age of 45.07 (18-65 years of age). Neither radiotherapy nor chemotherapy had been given to the patients before surgery. Histopathological examination performed intraoperatively as well as later, under paraffin, revealed 12 cases of malign tumours. The control group consisted of 18 women (blood donors), apparently healthy, with a mean age of 41 (30-49 years of age). In both groups, the immune status was assessed by means of: lymphocyte counts, T-lymphocyte counts (TL), rosetting, lymphocyte blastic transformation test (BLT) under the action of polyclonal mitogens, immunoglobulin dosing and Interleukin-2 (IL-2) determination in lymphocyte cultures stimulated with mitogens. The conclusion of our results has been that even in the less advanced stages of mammary cancer, there occur alterations of the immune response represented by: A decrease in the total number of lymphocytes, especially through a decrease of the TL number; A decrease of the lymphocyte blastic transformation index on stimulation with PHA; A decrease of IL-2 concentration in cultures stimulated with mitogens through the impairment of the TL CD4+ (TL Helper) function. The decrease of IL-2 production capacity influences the transmission of the immune message to the cytotoxic TL and thus impairs the cytotoxic effector component whose role is to remove tumoral cells. Evidence of IL-2 involvement in the immunodeficiency of mammary cancer patients could prove useful for diagnosis purposes and could plead in favour of the therapeutic potential of this interleukin.