Cooccurrences of Putative Endogenous Retrovirus-Associated Diseases
Sporadic amyotrophic lateral sclerosis may be an aetiologically heterogenous disease. We confirmed elevated circulating IgG immune complexes, and altered IgG seroreactivities against human retroviral antigens (HIV-2 and HTLV immunoblots) in overlapping subgroups of patients. Together with preliminary findings of a positive polymerase chain reactivity for human T-lymphotropic virus (HTLV.tax/rex) in blood leukocytes of 5 out of 14 sALS patients, we interpret this as evidence for a retroviral involvement in this relentlessly progressive, often asymmetrically spreading neurodegeneration. The possibility of a secondary phenomenon seems unlikely, yet cannot be completely ruled out.