GAD65

Paraneoplastic Neurological Syndromes (PNS) associated with this antibody:
- Stiff person syndrome
- Limbic encephalitis

Most frequently associated tumors:
- Non-paraneoplastic

GAD65 = glutamic acid decarboxylase enzyme links two neurotransmitter systems by catalyzing the decarboxylation of glutamate to synthesis GABA. GAD65 protein is mainly located in GABAergic axon terminals where it is functionally coupled to transport of GABA into synaptic vesicles and thereby mainly responsible for neurotransmission. In the cerebellum, Golgi cells in the granule layer expressing strongly GAD65 and Gad65-containing terminals are scattered within the neurophil or surrounding cell bodies and dendritic arborisation of the Purkinje neurons.