Recombinant Human IL-33 protein (Active)

Specifications

Form

Lyophilized

Additional notes

Purity >=95% by HPLC.

General info

Function

Cytokine that binds to and signals through the IL1RL1/ST2 receptor which in turn activates NF-kappa-B and MAPK signaling pathways in target cells (PubMed : 16286016, PubMed : 19841166). Involved in the maturation of Th2 cells inducing the secretion of T-helper type 2-associated cytokines (PubMed : 17853410, PubMed : 18836528). Also involved in activation of mast cells, basophils, eosinophils and natural killer cells (PubMed : 17853410, PubMed : 18836528). Acts as an enhancer of polarization of alternatively activated macrophages (PubMed : 19841166). Acts as a chemoattractant for Th2 cells, and may function as an 'alarmin', that amplifies immune responses during tissue injury (PubMed : 17853410, PubMed : 18836528). Induces rapid UCP2-dependent mitochondrial rewiring that attenuates the generation of reactive oxygen species and preserves the integrity of Krebs cycle required for persistent production of itaconate and subsequent GATA3-dependent differentiation of inflammation-resolving alternatively activated macrophages (By similarity).. In quiescent endothelia the uncleaved form is constitutively and abundantly expressed, and acts as a chromatin-associated nuclear factor with transcriptional repressor properties, it may sequester nuclear NF-kappaB/RELA, lowering expression of its targets (PubMed : 21734074). This form is rapidely lost upon angiogenic or pro-inflammatory activation (PubMed : 18787100).

Sequence similarities

Belongs to the IL-1 family. Highly divergent.

Post-translational modifications

The full-length protein can be released from cells and is able to signal via the IL1RL1/ST2 receptor. However, proteolytic processing by CELA1, CSTG/cathepsin G and ELANE/neutrophil elastase produces C-terminal peptides that are more active than the unprocessed full length protein (PubMed:22307629, PubMed:35794369). May also be proteolytically processed by calpains (PubMed:19596270, PubMed:22307629). Proteolytic cleavage mediated by apoptotic caspases including CASP3 and CASP7 results in IL33 inactivation (PubMed:19559631). In vitro proteolytic cleavage by CASP1 was reported (PubMed:16286016, PubMed:19439663) but could not be confirmed in vivo (PubMed:19465481) suggesting that IL33 is probably not a direct substrate for that caspase (PubMed:19439663, PubMed:19465481).

Subcellular localisation

Nucleus