Detection of Borna disease virus-reactive antibodies from patients with affective disorders by western immunoblot technique.

Borna disease (BD) virus is a partially characterized neurotropic agent with a predilection for neurons and astrocytes in the limbic system and cerebrum of infected hosts. Although it usually causes a fatal encephalitis, some laboratory animals which have been experimentally inoculated can develop a persistent non-fatal infection characterized by a neuro-behavioral syndrome akin to human manic-depression. Using immunofluorescent techniques, we previously observed BD virus-specific antibodies in the sera of 4.5% of affectively ill patients, with the highest titers present in bipolar patients. More recently, we have developed a sensitive Western blot assay for the detection of anti-BD virus antibodies to a 38/40 kDa and 24 kDa protein in human serum. In the present study, we screened 138 affectively ill patients and 117 healthy controls and observed a significantly great proportion of patients with antibodies to the 38/40 kDa protein (P < 0.0001), the 24 kDa protein (P < 0.05) and both the 38/40 kDa and 24 kDa proteins (P < 0.025). These data extend prior reports on the presence of BD virus-specific antibodies in psychiatric patients, and suggest that a BD virus-like agent may be associated with affective illness in humans.