The serum autoantibody testing was described for four subjects: the youngest subject with the preceding viral prodrome had antibodies against a 22-kDa antigen; one of the two subjects with pineal gland germinoma had antibodies against a 35-kDa optic nerve-derived antigen; the subject with LCH had antibodies against recoverin and a 62-kDa antigen; and our subject had antibodies against enolase, recoverin, tubulin, and pyruvate kinase M2. The gene discussed is RCVRN; the disease is Langerhans cell histiocytosis.