PT  - JOURNAL ARTICLE
AU  - Louahed, J
AU  - Kermouni, A
AU  - Van Snick, J
AU  - Renauld, J C
TI  - IL-9 induces expression of granzymes and high-affinity IgE receptor in murine T helper clones.
DP  - 1995 May 15
TA  - The Journal of Immunology
PG  - 5061--5070
VI  - 154
IP  - 10
4099  - http://www.jimmunol.org/content/154/10/5061.short
4100  - http://www.jimmunol.org/content/154/10/5061.full
SO  - J. Immunol.1995 May 15; 154
AB  - Interleukin 9 (IL-9) is a TH2 cytokine that has been shown to promote the antigen-independent growth of some mouse T helper clones. To characterize the specificity of IL-9-mediated T cell activation, we used a murine T cell clone that could grow with either IL-9 or IL-2. After differential hybridization of a cDNA library, we isolated three genes that were expressed preferentially in the presence of IL-9. Two of them correspond respectively to granzyme A and granzyme B, two proteases expressed by activated T cells. By Northern blot hybridization and functional assays, we found that IL-9 induced the expression of granzyme B in several T cell clones as well as in mast cell lines. In addition, other proteases such as the mouse mast cell proteases were also found to be expressed by IL-9-activated T cell clones. The third IL-9-induced cDNA corresponds to the alpha-chain of the high-affinity receptor for IgE. Several T cell clones expressed this IgE receptor mRNA and were able to bind IgE with high affinity. Taken together, our results indicate that IL-9 induces a mast cell-like phenotype in T cell clones.