Expression of interferon alpha receptors in cell lines from human tumors. Relationship with the antiproliferative effect
Perea, S.E.; Gerónimo, H.; López Saura, P.
Acta Cientifica Venezolana 44(1): 22-27
1993
ISSN/ISBN: 0001-5504 PMID: 8154235 Document Number: 419543
Alpha Interferon (IFN) membrane receptor expression was studied in four human tumor cell lines from several origins: Burkitt's lymphoma (Daudi cells), cervix adenocarcinoma (HeLa cells), larynx carcinoma (HEp-2 cells) and a grade III-IV glioblastoma (GL-5 cells). The number of receptors per cell expressed in each case did not correlate with the sensitivity of the cytostatic effect of IFN alpha-2b. However, the Scatchard analysis of the affinity of the IFN-receptor complex did correlate with this effect. Daudi cells, which expressed 1927 receptors/cells with a high affinity (Kd = 3.30 x 10(-10) M) were the most sensitive to the antiproliferative effect. Growth inhibition was 30% with only 1.6pg/ml of IFN. HeLa cells expressed a mixture of high (Kd = 3.36 x 10(-10) M) and low (Kd = 3.21 x 10(-9) M) affinity binding sites and were also sensitive to the antiproliferative effect but less than Daudi. HEp-2 and GL-5 cells, on the contrary, were very little sensitive to the antiproliferative effect of IFN and only expressed low affinity binding sites (Kd = 1.20 x 10(-8) M and Kd = 8.33 x 10(-9) M) respectively. On the other hand, IFN alpha-2b binding assays to peripheral blood lymphocytes from 8 healthy individuals were also carried out as normal cells for comparison. The values obtained were 433 +/- 166 receptors per cell and Kd = 3.68 2.66 x 10(-10) M.