Rosenthal L A, Klyczek K K, Blank K J
Graduate Group in Immunology, University of Pennsylvania, Philadelphia 19104.
Cell Immunol. 1992 Nov;145(1):43-55. doi: 10.1016/0008-8749(92)90311-c.
Kgv cells do not constitutively express class I mRNA or protein. Interferon (IFN)-gamma, but not IFN-alpha/beta, induces H-2Dk expression. IFN does not induce H-2Kk expression. We examined constitutive and IFN-inducible class I expression on Kgv cells stably transfected with genomic clones of H-2Kk or H-2Dk and on somatic cell hybrid lines constructed between Kgv cells and constitutively class I-positive cells of a distinguishable H-2 haplotype. Our results suggest that both the lack of constitutive class I expression and the inability of IFN-alpha/beta to induce class I expression on Kgv cells are primarily due to cis-regulatory mechanisms. However, stable introduction of the H-2Dk gene into Kgv cells conferred IFN-gamma inducibility upon the silent endogenous H-2Kk gene. Therefore, the failure of IFN-gamma to induce H-2Kk expression on Kgv cells is due, at least in part, to a trans-regulatory mechanism.
Kgv细胞不组成性表达I类mRNA或蛋白质。γ干扰素（IFN-γ）而非α/β干扰素可诱导H-2Dk表达。干扰素不诱导H-2Kk表达。我们检测了用H-2Kk或H-2Dk基因组克隆稳定转染的Kgv细胞以及在Kgv细胞与具有可区分H-2单倍型的组成性I类阳性细胞之间构建的体细胞杂交系上的组成性和干扰素诱导性I类表达。我们的结果表明，Kgv细胞缺乏组成性I类表达以及α/β干扰素无法在其上诱导I类表达主要是由于顺式调节机制。然而，将H-2Dk基因稳定导入Kgv细胞赋予了沉默的内源性H-2Kk基因γ干扰素诱导性。因此，γ干扰素无法在Kgv细胞上诱导H-2Kk表达至少部分是由于反式调节机制。
