Anti-eIF4E (phospho-S209) Antibody

Affinity-purified polyclonal antibody raised in rabbit against the phosphorylated serine-209 epitope of eIF4E, the cap-binding translation initiation factor. Phosphorylation at S209 is catalyzed by MNK1 and MNK2 kinases downstream of the RAS/ERK and p38 MAPK cascades, so detecting this modification is a standard readout for pathway activation in tumor biology, neuronal stress, and inflammation studies. Antibodies.com supplies this unconjugated reagent at 1 mg/ml in phosphate buffered saline containing 0.05% sodium azide at approximately pH 7.2, packaged as a 100 µl vial. The antibody is validated for immunohistochemistry on formalin-fixed paraffin-embedded tissue and cross-reacts with human, mouse, and rat samples, supporting comparative work across model systems and patient-derived specimens. For routine use, store the vial at 4°C; for longer-term storage, aliquot and freeze to limit repeated freeze-thaw cycles. The polyclonal format offers broader epitope coverage, which can help recover signal on phospho-epitopes that formalin fixation partially masks.