标题:The Synergistic Effect of Human Recombinant Interferon-α2a in Combination with Interferon-γ and the Induction of Interferon-α2a Receptor by Interferon-γ
摘要:An in vitro examination was made of the synergistic antiproliferative effect of recombinant interferon-γ (IFN-γ) with interferon-α2a (IFN-α2a) on human tumor cell lines, including lung small cell carcinoma QG-90, amelanotic melanoma HMV-1, renal carcinoma ACHN and Burkit lymphoma Daudi. Sixty-four percent of HMV-1 cells and 75% of ACHN cells seeded were killed by treatment with 10 pM and 1000 pM of IFN-γ, respectively. Furthermore, 69% of HMV-1 cells and 59% of ACHN cells were killed by 1000 pM of IFN-α2a. When HMV-1 was treated first with 10 pM of IFN-γ, and then with 1000 pM of IFN-α2a, 81% of cells seeded were killed (p<0.001). Similarly, 89% of ACHN cells were killed by the same sequential treatment with 1000 pM of IFN-γ, and then of IFN-α2a (p<0.001). However, adverse sequence of treatment could not produce such a synergistic result. On the surface of these susceptible cells, HMV-1 and ACHN, to both IFNs, the number of receptors for IFN-α2a increased significantly after treatment with IFN-γ without any serious change of the dissociation constant, suggesting that increase in the number of receptors for IFN-α2a may be the major mechanism of the synergistic effects of IFN-γ with IFN-α2a.