CD30L/CD30 is critical for maintenance of IL-17A-producing γδ T cells bearing Vγ6 in mucosa-associated tissues in mice.

CD30 ligand (CD30L, CD153), a member of the tumor necrosis factor (TNF) superfamily, and its receptor CD30 are important for differentiation and activation of CD4(+) T helper type 17 (Th17) cells. In this report, we demonstrate that the interleukin 17A (IL-17A)-producing γδ T cells normally developed in the fetal thymus, whereas Vγ1(-)Vγ4(-) γδ T cells expressed Vγ6/Vδ1 gene transcript selectively decreased in mucosa-associated tissues in naive CD30KO or CD30LKO mice. Moreover, CD30 and CD30L were expressed preferentially by Vγ1(-)Vγ4(-) γδ T cells in naive mice. The bacteria clearance was attenuated by the impaired response of the IL-17A-producing γδ T cells and decreased infiltration of neutrophils in CD30KO or CD30LKO mice. In vivo administration of agonistic anti-CD30 monoclonal antibody restored the ability of protection against Listeria monocytogenes by enhancing Vγ1(-)Vγ4(-) γδ T cells producing IL-17A not only in wild-type but also CD30LKO mice. Taken together, it appears that CD30L/CD30 signaling plays an important role in the maintenance and activation of IL-17A-producing γδ T cells presumably bearing Vγ6 in the mucosa-associated tissues of mice.

Selective redox regulation of cytokine receptor signaling by extracellular thioredoxin-1.

The thiol-disulfide oxidoreductase thioredoxin-1 (Trx1) is known to be secreted by leukocytes and to exhibit cytokine-like properties. Extracellular effects of Trx1 require a functional active site, suggesting a redox-based mechanism of action. However, specific cell surface proteins and pathways coupling extracellular Trx1 redox activity to cellular responses have not been identified so far. Using a mechanism-based kinetic trapping technique to identify disulfide exchange interactions on the intact surface of living lymphocytes, we found that Trx1 catalytically interacts with a single principal target protein. This target protein was identified as the tumor necrosis factor receptor superfamily member 8 (TNFRSF8/CD30). We demonstrate that the redox interaction is highly specific for both Trx1 and CD30 and that the redox state of CD30 determines its ability to engage the cognate ligand and transduce signals. Furthermore, we confirm that Trx1 affects CD30-dependent changes in lymphocyte effector function. Thus, we conclude that receptor-ligand signaling interactions can be selectively regulated by an extracellular redox catalyst.