@article {Elizabeth:March 2005:0019-2805:322, author = "Elizabeth Z. Managlia", author = "Alan Landay", author = "Lena Al-Harthi", title = "Interleukin-7 signalling is sufficient to phenotypically and functionally prime human CD4+ naive T cells", journal = "Immunology", volume = "114", year = "March 2005", abstract = "Summary

Interleukin-7 (IL-7) is produced by bone marrow and lymphoid stromal cells and is involved in the synthesis, survival and homeostasis of T cells. These attributes are the basis for current strategies to utilize IL-7 as an immune modulator for several clinical conditions to replenish depleted T-cell numbers. Because we had previously determined that IL-7 can induce potent human immunodeficiency virus replication in the otherwise non-permissive CD4+ naïve T-cell compartment, we evaluated here the impact of IL-7 on the phenotype and functional potential of naïve CD4+ T cells in an attempt to understand the mechanism of this induction. We demonstrate that IL-7 mediated the up-regulation of CD25, CD95 and human leucocyte antigen-DR, while it did not alter the expression of CD45RO, CD69, CD40, or CD154. Examination of the cytokine profile of IL-7-treated naïve T cells using a Type1/Type2 Proteome Array indicated a remarkable IL-7-mediated induction of interferon-ggr production, while the other cytokines evaluated (IL-2, IL-12, tumour necrosis factor-agr, IL-4, IL-5, IL-10 and IL-13) were not affected. Intracellular staining of IL-7-treated naïve T cells for interferon-ggr verified the Proteome data. IL-7 did not induce cell cycle proliferation of naïve CD4+ T cells, as evaluated by 7-AAD/pyronin immunostaining and carboxyfluorescein diacetate succinimidyl ester dye tracking. IL-7 treatment of naïve CD4+ T cells induced their ability to prime monocytes, as was indicated by induction of CD80 and CD86 expression on monocytes cocultured with IL-7-treated naïve CD4+ T cells. Collectively, these data indicate that IL-7 signalling is sufficient to phenotypically and functionally prime human CD4+ naïve T cells independent of antigen stimulation.", pages = "322-335(14)", url = "http://www.ingentaconnect.com/content/bsc/imm/2005/00000114/00000003/art00004" doi = "doi:10.1111/j.1365-2567.2004.02089.x" }