Anti-PTPN22 Antibody

PTPN22 (Protein Tyrosine Phosphatase Non-Receptor Type 22) is an intracellular lymphoid-specific phosphatase best known in the immunology literature for tuning T-cell receptor signaling through its effects on Lck, ZAP-70, and downstream NFAT/NF-κB pathways. The R620W (rs2476601) coding variant of PTPN22 is one of the strongest non-HLA risk alleles shared across rheumatoid arthritis, type 1 diabetes, systemic lupus erythematosus, and Graves' disease, which is why antibodies that cleanly detect endogenous PTPN22 protein in human, mouse, and rat samples are useful for autoimmune and signaling research.

This Antibodies.com reagent is supplied as 100 µl of unconjugated polyclonal antiserum at 1 mg/ml in PBS with 0.1% sodium azide and 50% glycerol as a cryoprotectant. The 50% glycerol formulation allows storage at -20 °C with minimal freeze-thaw damage, and the small azide concentration permits direct use in downstream assays without an additional purification step. Recommended applications validated for this lot are Western blot (WB) and immunohistochemistry (IHC), making it appropriate for expression profiling of lymphoid tissues, synovial biopsies, and cell-line lysates where PTPN22 regulation is being studied.

Reactivity has been confirmed against human, mouse, and rat PTPN22, supporting both cross-species expression studies and the use of rodent disease models alongside human clinical samples. The polyclonal format increases the chance of detecting multiple epitopes within the phosphatase domain, which can be helpful when probing truncated splice variants or mutant forms of the protein.