IL-27: An endogenous constitutive repressor of human monocytes.

We report here that human monocytes are repressed by endogenous IL-27, in that the addition of an anti-IL-27 neutralizing antibody increases the production of pro-inflammatory cytokines ex vivo. We observed that neutralizing monocyte-derived IL-27 leads to increased IL-17A production by CD4+ T cells and a down-regulation of the IL-17 modulating ectonucleotidase CD39 on monocytes. The locus that contains the IL27 gene has been linked to susceptibility for type 1 diabetes (T1D). Interestingly, ex vivo monocytes from subjects with T1D produce more IL-27 suggesting this upregulation of IL-27 acts as a negative feedback loop to attempt to counterbalance the pro-inflammatory immune response in the disease state. In summary, we provide evidence that IL-27 is an endogenous regulator of human monocytes and has consequences on CD4+ T cell phenotype, particularly Th17 cells.
PMID: 32531345 [PubMed - as supplied by publisher]

Source: Clinical Immunology - June 8, 2020 Category: Allergy & Immunology Authors: Frangieh M, McHenry A, Phillips R, Ye C, Bernier A, Laffell L, Elyaman W, Bradshaw EM Tags: Clin Immunol Source Type: research