First Author | Smith KA | Year | 2014 |
Journal | Eur J Immunol | Volume | 44 |
Issue | 1 | Pages | 150-61 |
PubMed ID | 24185641 | Mgi Jnum | J:209008 |
Mgi Id | MGI:5565546 | Doi | 10.1002/eji.201343746 |
Citation | Smith KA, et al. (2014) IL-6 controls susceptibility to helminth infection by impeding Th2 responsiveness and altering the Treg phenotype in vivo. Eur J Immunol 44(1):150-61 |
abstractText | IL-6 plays a pivotal role in favoring T-cell commitment toward a Th17 cell rather than Treg-cell phenotype, as established through in vitro model systems. We predicted that in the absence of IL-6, mice infected with the gastrointestinal helminth Heligmosomoides polygyrus would show reduced Th17-cell responses, but also enhanced Treg-cell activity and consequently greater susceptibility. Surprisingly, worm expulsion was markedly potentiated in IL-6-deficient mice, with significantly stronger adaptive Th2 responses in both IL-6(-/-) mice and BALB/c recipients of neutralizing anti-IL-6 monoclonal Ab. Although IL-6-deficient mice showed lower steady-state Th17-cell levels, IL-6-independent Th17-cell responses occurred during in vivo infection. We excluded the Th17 response as a factor in protection, as Ab neutralization did not modify immunity to H. polygyrus infection in BALB/c mice. Resistance did correlate with significant changes to the associated Treg-cell phenotype however, as IL-6-deficient mice displayed reduced expression of Foxp3, Helios, and GATA-3, and enhanced production of cytokines within the Treg-cell population. Administration of an anti-IL-2:IL-2 complex boosted Treg-cell proportions in vivo, reduced adaptive Th2 responses to WT levels, and fully restored susceptibility to H. polygyrus in IL-6-deficient mice. Thus, in vivo, IL-6 limits the Th2 response, modifies the Treg-cell phenotype, and promotes host susceptibility following helminth infection. |