THYMOPENTIN, FACTOR AF2, AND POLYERGA IMPROVE IMPAIRED MITOGEN-INDUCED INTERFERON-GAMMA RELEASE OF PERIPHERAL-BLOOD MONONUCLEAR-CELLS DERIVED FROM TUMOR PATIENTS

The effect of three different biological response modifiers (BRM) thym opentin (TP5) factor AF2 and polyerga on mitogen induced interferon-ga mma release by peripheral blood mononuclear cells (PBMC) was tested in 23 healthy humans and in 23 tumor patients. All patients were prior t o surgery and had not yet received radio- or chemotherapy at the time of examination. The interferon-gamma concentration in the supernatants was measured by an enzyme-linked immunosorbent assay (ELISA). The cel ls were stimulated with PHA at 7.5 mug/mL. In the reference group, int erferon-gamma concentration rose to a median of 2190 pg/mL and to 875 pg/mL in the tumor patients. The difference was statistically signific ant (p < 0.05). However, an addition of the three different BRM did no t have any significant influences on interferon-gamma concentration in healthy references. In contrast, in tumor patients cocultivation with each BRM increased interferon-gamma release significantly. The most s ignificant increases could be achieved with 100 mug/mL TP5 (median val ue 1300 pg/mL IFN-gamma, p < 0.001), 100 mug/mL factor AF2 (median val ue 1375 pg/mL IFN-gamma, p < 0.001), and 0.5 mg/mL polyerga (median va lue 1850 pg/mL IFN-gamma, p < 0.0001). At these concentrations the dif ference between the tumor patients and the reference group was no long er significant. Polyerga and thymopentin. showed slightly but not sign ificantly higher increase than factor AF2 compared to the stimulation with mitogen alone. Flow cytometry analysis of CD3, CD4, CD8, CD16, CD 19, CD56 and HLA-DR expression of the PBMC revealed slightly but not s ignificantly higher values for CD16-positive cells and HLA-DR positive cells, respectively, in the tumor patients.