T-cell restricted and unrestricted expression of transfected human interleukin-2 gene: Phorbol ester- and calcium-inducible versus constitutive expression

Alberto Gulino, Alessandra Vacca, Antonietta R. Farina, Isabella Screpanti, Marella Maroder, Angela Gismondi, Angela Santoni, Luigi Frati, Jennifer D. Luethy, Nikki J. Holbrook

Research output: Contribution to journalArticlepeer-review

Abstract

Interleukin-2 (IL-2)gene expression is tightly controlled and generally limited to antigenic stimulation of T cells. To study the cell-specific expression of the IL-2 gene, we transfected the intact human IL-2 gene, including 2.0 kb of 5′ and 0.3 kb of 3′ flanking sequences, into mouse NIH-3T3 fibroblasts and BFS lymphoma T cells and into human epithelial HeLa cells. Stable transformants (NIH-3T3,HeLa and BFS cells) carried an intact transfected IL-2 gene and constitutively expressed cytoplasmic human IL-2 mRNA which was not detected in vector-transfected cells. Constitutive expression of IL-2 mRNA in human IL-2 gene-transfected NIH-3T3 and HeLa cells was associated to the secretion of bioactive IL-2 protein, while no IL-2production was observed in untransfected or vector-transfected cells. Cytoplasmic IL-2 mRNA observed in transfectants was larger (1.4 kb) than endogenous IL-2 mRNA of human T cells, although smaller than RNA containing unspliced intact introns. No alternative promoters or polyadenylation signals were used by these cells, but some intronic sequences were present in the 1.4 kb mRNA. Phorbol ester and calcium ionophore did not modulate the expression of the transfected IL-2 gene in NIH-3T3 and HeLa cells, while these agents increased its expression in transfected BFS lymphoma T cells. We conclude that when transfected into lymphoid and non-lymphoid cells the intact human IL-2 gene is constitutively expressed, while its phorbol ester / calcium-mediated inducible expression is restricted to T cells. This suggests that the constitutive and inducible expression of the IL-2 gene can be dissociated and are presumably subjected to separate regulatory pathways.

Original languageEnglish
Pages (from-to)7-17
Number of pages11
JournalBBA - Gene Structure and Expression
Volume1087
Issue number1
DOIs
Publication statusPublished - Sep 10 1990

Keywords

  • (Human)
  • Calcium-inducible expression
  • Gene transfection
  • Interleukin-2 gene
  • T cell

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Genetics
  • Structural Biology

Fingerprint Dive into the research topics of 'T-cell restricted and unrestricted expression of transfected human interleukin-2 gene: Phorbol ester- and calcium-inducible versus constitutive expression'. Together they form a unique fingerprint.

Cite this