Cloning of a partial cDNA for rat interleukin-12 (IL-12) and analysis of IL-12 expression in vivo

Scand J Immunol. 1996 Jul;44(1):11-4. doi: 10.1046/j.1365-3083.1996.d01-279.x.


Experimental models of autoimmunity in the rat may feature selective activation of either the Th1 or Th2 subset of helper T cells. Interleukin-12 (IL-12) is a key cytokine in the development of Th1 responses. In order to study IL-12 in the rat we used polymerase chain reaction (PCR) primers based on murine IL-12 to amplify a partial cDNA from rat tissue. The product was cloned and sequenced: it shows 94% nucleotide identity with the murine gene and 94% identity of predicted amino acid sequence. Primers based on the rat IL-12 sequence were used to analyse IL-12 expression in vivo using semi-quantitative PCR. We studied RNA from lymphoid tissues of two rat strains which differ in their response to mercuric chloride (HgCl2): Brown Norway (BN) rats develop autoimmunity with a predominant Th2 response; Lewis rats are resistant. Interleukin-12 expression was higher in Lewis than BN, and higher in spleen than lymph node. After HgCl2, IL-12 expression increased in BN towards the time when the autoimmune response autoregulates. Variation in baseline levels of IL-12 expression may account for the Th2 predisposition of BN rats compared to Lewis rats; IL-12 may play a role in the autoregulation of the Th2 response induced by HgCl2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary / isolation & purification*
  • Gene Expression Regulation / drug effects
  • Interleukin-12 / biosynthesis
  • Interleukin-12 / genetics*
  • Interleukin-12 / isolation & purification*
  • Lymph Nodes / metabolism
  • Mercuric Chloride / pharmacology
  • Molecular Sequence Data
  • Rats
  • Rats, Inbred BN
  • Rats, Inbred Lew
  • Spleen / metabolism


  • DNA, Complementary
  • Interleukin-12
  • Mercuric Chloride

Associated data

  • GENBANK/S82489