IgG subclass serum levels in systemic lupus erythematosus patients.

IgG subclass levels of sera from 105 patients with systemic lupus erythematosus (SLE) were determined by immunonephelometric assay. Patients were divided into two groups according to clinical activity of the disease: active disease and remission. Forty-five normal controls were also measured. We found a significant increase of IgG1 (p = 0.000), IgG2 (p = 0.000), and IgG3 (p = 0.000) in SLE sera, while IgG4 (p = 0.494) values did not differ significantly from those of controls. When patients were divided according to clinical activity, decrease of IgG3 concentration was observed in the patients in remission. In contrast, the concentrations of IgG1, IgG2, and IgG4 subclass were similar between the two groups (p > 0.05). Our data suggest that differential increase of IgG subclasses during the course of SLE may be of relevance to the pathogenesis of the disease.

Sequence identity between the genomes of humans and viruses.

OBJECTIVE: People exposed to viruses usually do not develop diseases. Viruses cause diseases; however, most of the pathologic effects of these diseases are not caused directly by the viruses but by the side effects of the immune response. It is possible that sequence identity may exist between viruses and humans and may be biologically relevant to the infection of virus. The aim of this study was to find out whether sequence identity exists between viruses and humans. METHODS: BLAST searches of virus genome sequences against human genome were performed using the resources of the National Center for Biotechnology Information (NCBI). RESULTS: All the viruses that were compared to humans contain different numbers of short identical regions to the human genome. Each identical region was 20-30 nt and some were found at multiple sites within the human genome. CONCLUSION: A new role of the virus in the relationship between viruses and humans was taken into account. We assume that viruses have brought their sequence into the human genome in the long past history of human-virus interaction. In the process, viruses play roles as carriers to transfer external sequence information into the human genome.