ShK Toxin
Venom Peptide / AutoimmuneAlso known as: ShK, Stichodactyla helianthus toxin
Sea Anemone Venom PeptidesResearch phase: Preclinical (parent); Phase 1b (dalazatide/ShK-186)Regulatory: Not approved. Parent compound; see dalazatide for clinical analog.
Mechanism
ShK toxin is a sea anemone peptide that selectively blocks Kv1.3 potassium channels on immune cells. This makes it a promising lead for treating autoimmune diseases like multiple sclerosis.
Technical detail
ShK is a 35-amino acid peptide from Stichodactyla helianthus with three disulfide bonds. It blocks Kv1.3 channels (IC50 ~11 pM) which are selectively upregulated on effector memory T cells (TEM) driving autoimmune pathology. Kv1.3 blockade suppresses TEM proliferation and cytokine production while sparing naive and central memory T cells.