Niu P D, Lefevre F, La Bonnardiere C
Laboratoire de Virologie et Immunologie moleculaire INRA, Jouy-en-josas, France.
J Interferon Cytokine Res. 1995 Sep;15(9):769-75. doi: 10.1089/jir.1995.15.769.
The short porcine type I interferon (spI IFN), encoded by a gene physiologically expressed by the pig embryonic trophoblast during implantation, represents the first member of a novel family type I IFN. Binding and cross-linking experiments were carried out to characterize its cellular receptor. On porcine kidney cells, specific binding of 125I-spI IFN could be displaced significantly by spI IFN, rpIFN-alpha 1, and rhIFN-alpha 1, but not by rhIFN-alpha 2a or by rpIFN-gamma. On the other hand, all these type I IFNs but not rpIFN-gamma were capable of displacing bound 32P-hIFN-alpha A-P1 on these cells. Cross-linking data show that the specific 120 kD complex formed with these two radiolabeled ligands was displaceable by an excess of both spI IFN and rpIFN-alpha 1. These results provide primary evidence that spI IFN shares at least the major binding subunit of type I IFN receptor on porcine cells. On human WISH cells, 125I-spI IFN did not form any complex, nor did spI IFN affect cross-linking complexes of 32P-hIFN-alpha A-P1 on these cells, unlike rpIFN-alpha 1. The lack of antiviral and antiproliferative effects of spI IFN on human cells is primarily a result of its inability to recognize human type I IFN receptor.
短猪I型干扰素（spI IFN）由猪胚胎滋养层在着床期间生理表达的一个基因编码，是新型I型干扰素家族的首个成员。进行了结合和交联实验以表征其细胞受体。在猪肾细胞上，125I-spI IFN的特异性结合可被spI IFN、rpIFN-α1和rhIFN-α1显著取代，但不能被rhIFN-α2a或rpIFN-γ取代。另一方面，所有这些I型干扰素（但不包括rpIFN-γ）都能够取代这些细胞上结合的32P-hIFN-αA-P1。交联数据表明，与这两种放射性标记配体形成的特异性120 kD复合物可被过量的spI IFN和rpIFN-α1取代。这些结果提供了初步证据，表明spI IFN在猪细胞上至少共享I型干扰素受体的主要结合亚基。在人WISH细胞上，125I-spI IFN不形成任何复合物，spI IFN也不像rpIFN-α1那样影响这些细胞上32P-hIFN-αA-P1的交联复合物。spI IFN对人细胞缺乏抗病毒和抗增殖作用主要是由于其无法识别人类I型干扰素受体。
