Thermo Fisher Scientific IL-21 Polyclonal Antibody, Biotin, PeproTech

Applications and Tested Dilution

Product Specifications

Product Specific Information

AA Sequence of recombinant protein:
MHKSSPQGPD RLLIRLRHLI DIVEQLKIYE NDLDPELLSA PQDVKGHCEH AAFACFQKAK LKPSNPGNNK TFIIDLVAQL RRRLPARRGG KKQKHIAKCP SCDSYEKRTP KEFLERLKWL LQKMIHQHLS

Preparation:
Produced from sera of rabbits immunized with highly pure Recombinant Murine IL-21. Anti-Murine IL-21-specific antibody was purified by affinity chromatography and then biotinylated.

Sandwich ELISA:
To detect mIL-21 by sandwich ELISA (using 100 µL/well antibody solution), use this antibody at 0.25–1.0 µg/mL. When combined with PeproTech Polyclonal Anti-Murine IL-21 (500-P278) as a capture antibody, it allows detection of at least 0.2–0.4 ng/well of Recombinant mIL-21.

Western Blot:
For Western blot detection of mIL-21, use 0.1–0.2 µg/mL. With compatible secondary reagents, the detection limit for Recombinant mIL-21 is 1.5–3.0 ng/lane under both reducing and non-reducing conditions.

Packaging:
500-P278BT-1MG is provided as 2 × 500 µg.

Target Information

IL-21 is a 17 kDa immunomodulatory cytokine produced mainly by Natural Killer T (NKT) cells, T helper 17 (Th17), and T follicular helper (TFH) cells.
In TFH cells, IL-21 expression triggers autocrine signaling via IL-21R and STAT3, leading to transcriptional activation by Bcl6. Similar to IFN-γ in Th1 and IL-4 in Th2 cells, IL-21 is essential for TFH cell development and effector function.

IL-21 regulates T cell-dependent B cell differentiation into plasma and memory cells, promotes IgG production, and induces apoptosis in naive B cells.
In Th17 cells, IL-21 and its feedback through STAT3, IRF4, and RORγt upregulate IL-23R, supporting Th17 cell maturation and maintenance. Concurrently, IL-21 downregulates Foxp3.

IL-21-deficient mice show resistance to chemically induced colitis due to impaired Th17-associated molecule upregulation, whereas elevated IL-21 levels are found in colitis models.

For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.