Cell-mediated immune response to human myelin basic protein was studied
by the macrophage migration inhibition factor test in 17 autistic patients
and a control group of 11 patients suffering from other mental diseases
included in the differential diagnosis of the syndrome of autism. Of the 17
autistic patients, 13 demonstrated inhibition of macrophage migration,
whereas none of the nonautistic patients showed such a response. The
results indicate the existence of a cell-mediated immune response to brain
tissue in the syndrome of autism.