Does exposure to rubella virus generate endocrine autoimmunity?

Rubella virus is a possible environmental agent which may be involved in triggering autoimmunity to pancreatic islet cells, leading to Type 1 diabetes. Autoantibody responses were determined in 239 10-year-old girls who received live attenuated rubella vaccine, of whom 61 (26%) had no pre-existing rubella immunity. Islet cell antibodies (ICA greater than 5 Juvenile Diabetes Foundation (JDF) units) were present in seven (2.9%) girls before vaccination, and they appeared in three more 6 weeks after vaccination (4.2%). However, the ICA levels were low in all cases and of the three girls who developed ICA greater than 5 JDF units 6 weeks post-vaccination, none had detectable ICA 18 months later. IgG-insulin autoantibodies were present in 17 (7.1%) girls before vaccination, and their prevalence decreased after vaccination (5.4%). Thyroid antibodies (thyroglobulin and microsomal) were present in 2% and 1%, respectively, of the girls before vaccination and none appeared afterwards. Thus, rubella vaccination did not elicit widespread endocrine autoantibody production and viral triggering of endocrine autoimmunity in susceptible subjects remains an open question.