Anti-STAT4 (Ab-693) Antibody

Phosphorylation of Signal Transducer and Activator of Transcription 4 at the activating Tyr693 residue is captured by this polyclonal antibody raised in rabbit host. Validated for Western blot (WB) and immunohistochemistry (IHC), the unconjugated reagent from Antibodies.com is supplied as 100 µl and cross-reacts with Human, Mouse, and Rat samples, supporting translational work that spans rodent disease models and human clinical material.

Downstream of IL-12 and IL-23 receptor signaling through JAK2 and TYK2 kinases, phospho-STAT4 drives Th1 differentiation of CD4+ T cells, supports cytotoxic maturation of NK cells, and sustains IFN-gamma transcriptional programs during viral and intracellular pathogen challenges. Researchers apply this reagent to characterize tumor-infiltrating lymphocyte activity, map cytokine signaling in inflamed synovium, and dissect signaling deficits in autoimmune conditions such as systemic lupus erythematosus and rheumatoid arthritis.

For Western blot, cleared cell or tissue lysates are separated by SDS-PAGE and probed with the antibody, which detects a band near 86 kDa corresponding to full-length phospho-STAT4. Immunohistochemistry is performed on formalin-fixed paraffin-embedded (FFPE) sections using antigen retrieval conditions, with staining visualized in lymphoid organs, tumor biopsies, and inflamed tissues. Aliquoting the antibody upon first use limits freeze-thaw cycles and preserves phospho-epitope recognition across repeated experiments.