Dataset Information

Tryptophan (W) at position 37 of murine IL-12/IL-23 p40 is mandatory for binding to IL-12Rβ1 and subsequent signal transduction.

ABSTRACT: Interleukin (IL)-12 and IL-23 are composite cytokines consisting of p35/p40 and p19/p40, respectively, which signal via the common IL-12 receptor β1 (IL-12Rβ1) and the cytokine-specific receptors IL-12Rβ2 and IL-23R. Previous data showed that the p40 component interacts with IL-12Rβ1, whereas p19 and p35 subunits solely bind to IL-23R and IL-12Rβ2, resulting in tetrameric signaling complexes. In the absence of p19 and p35, p40 forms homodimers and may induce signaling via IL-12Rβ1 homodimers. The critical amino acids of p19 and p35 required for binding to IL-12Rβ2 and IL-23R are known, and two regions of p40 critical for binding to IL-12Rβ1 have recently been identified. In order to characterize the involvement of the N-terminal region of p40 in binding to IL-12Rβ1, we generated deletion variants of the p40-p19 fusion cytokine. We found that an N-terminal deletion variant missing amino acids M23 to P39 failed to induce IL-23-dependent signaling and did not bind to IL-12Rβ1, whereas binding to IL-23R was maintained. Amino acid replacements showed that p40W37K largely abolished IL-23-induced signal transduction and binding to IL-12Rβ1, but not binding to IL-23R. Combining p40W37K with D36K and T38K mutations eliminated the biological activity of IL-23. Finally, homodimeric p40D36K/W37K/T38K did not interact with IL-12Rβ1, indicating binding of homodimeric p40 to IL-12Rβ1 is comparable to the interaction of IL-23/IL-12 and IL-12Rβ1. In summary, we have defined D36, W37, and T38 as hotspot amino acids for the interaction of IL-12/IL-23 p40 with IL-12Rβ1. Structural insights into cytokine-cytokine receptor binding are important to develop novel therapeutic strategies.

SUBMITTER: Georgy J

PROVIDER: S-EPMC8571081 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Periodontitis is one of the most prevalent chronic inflammatory diseases and is induced by the interaction between oral microorganisms and the host immune system. Plasma cells are of special interest in chronic periodontitis (CP), as they represent ~50% of infiltrated immune cells in periodontal lesions. Plasma cells constitute the only known cell type capable of antibody production; however, recent evidence supports an emerging role for distinct sets of plasma cells in cytokine production. However, the presence of cytokine-producing plasma cells in CP is unknown. In this study, we used immunohistochemistry to detect significantly elevated levels of IL-35 and IL-37 (2 recently identified anti-inflammatory cytokines) in CP gingival tissue as compared with healthy tissue. Remarkably, we demonstrate that CD138+ CD38+ plasma cells are the major immune cell type in CP gingival tissues and that these cells produce IL-35 and IL-37. We used immunofluorescence and confocal microscopy analysis to identify a subset of plasma cells with robust cytoplasmic expression of IL-37-we denote this subset as IL-37-producing plasma cells (CD138+CD38+PIL-37). Another subset of plasma cells coproduces IL-35 and IL-37 and is denoted as IL-37/IL-35-coproducing plasma cells (CD138+CD38+PIL-35/IL-37). We determined that these 2 plasma cell subsets are IgG+plasma cells. Moreover, we show that human recombinant IL-35 and IL-37 exhibit a dose-dependent inhibition of osteoclast formation in vitro (~78.9% and 97.7% inhibition in 300 ng/mL of IL-35 and IL-37, respectively, P < 0.05). Overall, our findings suggest that PIL-37 and PIL-35/IL-37 exist as subsets of plasma cells in CP lesions and that these 2 new types of plasma cells may regulate periodontitis pathogenesis by inhibiting alveolar bone loss through directly blocking osteoclast formation. Importantly, these data suggest a novel role of plasma cells and offer potential new mechanistic and regulatory targets to be investigated in the context of periodontal health and disease.

Dataset Information

Tryptophan (W) at position 37 of murine IL-12/IL-23 p40 is mandatory for binding to IL-12Rβ1 and subsequent signal transduction.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets