Mao C, Davies D, Kerr I M, Stark G R
Imperial Cancer Research Fund, London, United Kingdom.
Proc Natl Acad Sci U S A. 1993 Apr 1;90(7):2880-4. doi: 10.1073/pnas.90.7.2880.
Using immunoselection, we have isolated 11 independent mutant HT1080 fibrosarcoma cell lines defective in the induction by interferon gamma (IFN-gamma) of the expression of the human leukocyte antigen HLA-DRA. The mutations are recessive and fall into five complementation groups. All the mutants are affected mainly in the expression of major histocompatibility complex class II and invariant-chain genes. Type I mutants (three complementation groups) are completely defective in induction of the invariant-chain and class II HLA-DP, -DQ, -DR, and -DM genes, whereas type II mutants (two complementation groups) induce these genes weakly in response to IFN-gamma, in the order DPB > DRA > invariant chain. The induction by IFN-gamma of the mRNAs for class I, TAP1, LMP7, and 9-27 is partially defective and the induction of the proteins IRF-1 and ICAM-1 is normal in both types of mutants. All the mutants respond normally to IFN-alpha. The mutants are stable and thus can be used to clone the affected genes by reversion.
利用免疫选择法，我们分离出了11个独立的突变型HT1080纤维肉瘤细胞系，这些细胞系在γ干扰素（IFN-γ）诱导人类白细胞抗原HLA-DRA表达方面存在缺陷。这些突变是隐性的，可分为五个互补组。所有突变体主要在主要组织相容性复合体II类和恒定链基因的表达上受到影响。I型突变体（三个互补组）在诱导恒定链以及II类HLA-DP、-DQ、-DR和-DM基因方面完全缺陷，而II型突变体（两个互补组）对IFN-γ的反应中诱导这些基因的能力较弱，顺序为DPB > DRA > 恒定链。在这两种类型的突变体中，IFN-γ对I类、TAP1、LMP7和9-27 mRNA的诱导存在部分缺陷，而对IRF-1和ICAM-1蛋白的诱导正常。所有突变体对α干扰素反应正常。这些突变体是稳定的，因此可用于通过回复突变来克隆受影响的基因。
