Expression of sequence variants of endogenous retrovirus RGH in particle form in multiple sclerosis

Abstract

The results were negative. To assess whether RGH sequences in particulate form could be associated with multiple sclerosis in vivo, we did blinded RT-PCR on clinical samples of cell-free, filtered, ultracentrifuged plasma from patients with multiple sclerosis or patients with autoimmune diseases, and from healthy controls (table). Expression of RGH sequences at particle level was specific for multiple sclerosis and all patients with active multiple sclerosis at the time of sampling were RGH positive. This finding shows in many patients, multiple sclerosis is associated with production into the blood of retroviral particles containing RGH sequences, possibly related to disease activity. RGH-2 sequence variants were found in the virus particles from cell-line supernatants and in the particulate fractions of plasma from patients with multiple sclerosis. Several RGH sequences were isolated from individual plasma samples from patients with multiple sclerosis. The range of homology to RGH was 80–95%. Whether the retroviral proteins in the particles are encoded by RGH needs to be assessed. The virion proteins may also be encoded by other retroviral sequences in the genome since heterologous RNA copackaging in virions is a well-known phenomenon. ERV-9 and type-C-related sequences have been reported in plasma samples from five patients with multiple sclerosis 4