Voltage-Gated Potassium Channel Antibody Unit Converter

Voltage-gated potassium channel (VGKC) complex antibodies are autoantibodies that target proteins associated with potassium channels in the nervous system. These channels help regulate the electrical activity of nerve cells.

Despite the name, these antibodies do not actually target the potassium channels themselves. Instead, they bind to proteins that are closely associated with the channels, most importantly LGI1 (leucine-rich glioma-inactivated 1) and CASPR2 (contactin-associated protein-like 2).

A positive VGKC test is most clinically meaningful when it reflects the presence of LGI1 or CASPR2 antibodies. Results that are positive for VGKC but negative for both LGI1 and CASPR2 (called "double-negative") are common and generally have limited clinical significance.

VGKC-complex antibodies are produced by B cells of the immune system as part of an autoimmune response. The potassium channels and their associated proteins (LGI1 and CASPR2) are found on nerve cells throughout the brain and peripheral nervous system, with LGI1 being especially concentrated in the hippocampus and limbic system.