Several gangliosides of human nervous tissues have been reported to be potential target antigens in autoimmune neuropathies. To explain the diversity of clinical symptoms in patients with antiganglioside antibodies, we have searched for ganglioside antigens that are specific to individual nervous tissues such as motoneurons, peripheral motor nerves, and sensory nerves. Although the major ganglioside compositions were not different among human peripheral motor and sensory nerves, fucosyl-GM1 was found to be expressed in sensory nervous tissue but not in spinal cord, motor nerve, and sympathetic ganglia. Sera from several patients with sensory nerve involvement also reacted with fucosyl-GM1 as well as GM1. Thus, fucosyl-GM1 may be a responsible target antigen for developing sensory symptoms in some patients with autoimmune neuropathies.