cDNA cloning and characterization of interleukin 2-induced genes in a cloned T helper lymphocyte.

Clonal expansion of antigen-specific lymphocytes is an important aspect of the immune response. Interleukin 2 (IL2) is largely responsible for the amplification of antigen-specific T cells. In this study, the changes in gene expression accompanying interleukin 2 stimulation of T cells are examined, using a cloned T helper lymphocyte line as a model system. To isolate cDNA clones of IL2-induced genes, a cDNA library was screened by differential hybridization. Twenty-one different cDNA clones were isolated by this method, comprising six glycolytic enzymes, vimentin, alpha-tubulin, beta-actin, gamma-actin, ERp99, elongation factor 2, ribosomal phosphoprotein P1, the DNA-binding protein dbpB/YB-1, as well as seven clones which do not correspond to any previously described sequences. These clones are used to study the time course of expression and the sensitivity to cycloheximide inhibition of IL2-induced mRNAs. In addition, the tissue specificity of the unidentified mRNAs is examined, and two of these are shown to be expressed at high levels in normal mouse brain, with much lower or undetectable levels in the other tissues tested. These cDNA clones will be useful in future studies to determine the molecular basis of IL2-induced gene expression.