| Analyses of ALS patient sera have identified circulating antibodies secreted by denervated muscle. These antibodies inhibit the stimulation of the sprouting of axons, the long arms of neurons which conduct nervous impulses to other neurons throughout the body (Onion 1998).
Researchers have found an immunoglobulin that affects the conductance of neuronal voltage-activated calcium channels which may induce an excessive release of glutamate from nerve endings (Onion 1998).
Several studies of ALS patients found the presence of antibodies that interact with motor neurons (Pestronk et al. 1988a; Pestronk et al. 1988b; Pestronk et al. 1989; Niebroj-Dobosz et al. 1999). Immune complexes have been found in spinal cords of patients with ALS.
It has been proposed that T cells, activated microglia, and immunoglobulin G (IgG) within the spinal cord lesions may be the primary event that leads to tissue destruction in ALS. |