Incidence of anti-intermediate filament antibody in serum samples of students with suspected glandular fever

Prevention of MS Requires Intervention on the Causes of the Disease: Reconciling Genes, Epigenetics, and Epstein Barr Virus

Prevention of multiple sclerosis requires intervention on modifiable causes of the condition making it necessary to establish what those causes are. MS is often stated to be a polygenic disease, with causal contributions from environmental factors and gene-environment interactions, implying an additive and independent relationship of these factors. Mechanistically there are no independent contributions of genes or environmental factors to traits. This model is unrealistic but still useful and underlies the concept of heritability, a foundational parameter in population genetics. However, it perpetuates a debate on an irreconcilable dichotomy about whether MS is primarily genetic or environmental. In particular, epidemiological evidence now exists for a causal, possibly even necessary, role for Epstein Barr Virus in MS. The additive model makes it unintuitive to reconcile MS as a genetic disease but also independently a viral illness. In this perspective it is argued that starting from a realistic interaction only model, based on broadly accepted biological premises, and working forward to explain why the classical additive model gives useful results, there is actually no paradox. An integrated approach using population genetic studies, immunology and molecular virology offers a particularly promising route to establish the elusive role of EBV in MS pathology, as EBV is a large and complex virus and its latency, dysregulated in most EBV-related pathologies, is hard to study in vivo. This approach may offer a route to prevention of MS altogether.

Epstein-Barr virus-induced autoimmune responses. I. Immunoglobulin M autoantibodies to proteins mimicking and not mimicking Epstein-Barr virus nuclear antigen-1

In previous studies of infectious mononucleosis, we found IgM autoantibodies which react with hematopoietic cell antigens. Many of these were inhibited by synthetic glycine/alanine peptides representing the glycine/alanine repeat of Epstein-Barr virus nuclear antigen-1. We have cloned and expressed fragments of genes encoding two of these autoantigens. One gene (p542) encodes a protein containing a glycine-rich 28-mer, which is its chief autoantigenic epitope and which represents a newly identified class of evolutionarily conserved autoepitopes. The other gene (p554) encodes a protein that is not demonstrably cross-reactive with Epstein-Barr virus nuclear antigen-1 or with any other EBV protein, but forms complexes with other proteins. Immunoaffinity-purified anti-p542 and anti-p554 have relatively high binding affinities, as evidenced by inhibition at 10(6)-10(8) M-1, and neither autoantibody showed polyreactivity with other common antigens. The data thus suggest that neither autoantibody is simply an expression of polyclonal B cell activation. We conclude that the two autoantigens stimulate autoantibody synthesis by different mechanisms. One autoantigen shares homology to a viral protein which generates cross-reacting antibodies to the autoantigenic epitope. The other has no recognizable cross-reaction with the infecting pathogen and may become immunogenic through complexing with other proteins.

Cytoskeletal binding of monoclonal anti-DNA antibodies derived from tonsillar lymphoid cells of a normal subject

The ability of monoclonal IgM anti-DNA autoantibodies derived from normal human lymphoid cells to bind to cellular constituents of human epithelial cells (HEp-2) was examined by immunofluorescence. Hybridoma supernatants from 10 different clones were studied. Four of them gave a strong fibrillar cytoplasmic staining that resembled cytoskeletal staining, 1 showed strong nuclear staining only, 3 showed weak nucleolar staining only, and 2 showed no staining. The hybridoma supernatants that reacted with HEp-2 cytoskeleton were either polyspecific for various nucleic acid antigens, such as single-stranded DNA, DNA, poly(dA:dT), poly(dG).poly(dC), RNA, and cardiolipin, or were restricted to cardiolipin. Cytoskeletal staining identical to the hybridoma supernatant staining was also seen with mouse monoclonal anti-vimentin antibody B11.5.1. Inhibition of the cytoskeletal staining was accomplished in 3 of the 4 hybridoma supernatants by preabsorption of these hybridoma supernatants with cardiolipin and/or single-stranded DNA, or by preincubation of the HEp-2 cells with the mouse monoclonal anti-vimentin antibody.

Anti-intermediate filament antibodies, antikeratin antibody, and antiperinuclear factor in rheumatoid arthritis and infectious mononucleosis

Sera from patients with rheumatoid arthritis (RA), patients with infectious mononucleosis (IM), and blood donors were tested by indirect immunofluorescence for the presence of antikeratin antibody (AKA), antibody to cytoskeletal intermediate filaments of prekeratin or vimentin type (AIFA) and antiperinuclear factor (APF). In 81.9% of the RA sera and 92.5% of the IM sera AIFA of IgM class was found at titres up to and in some cases exceeding 1/160. In blood donors the incidence of AIFA was 26%, at titres not exceeding 1/20. AKA and APF, always of IgG class, were found in 54.2% and 73.6% of rheumatoid sera. A weak correlation was found in RA between the incidence of AIFA and APF. AKA was not present in either IM or blood donor sera, and APF was found in only 2.5% and 3.2% of IM or blood donors respectively.