Background: There are substantial differences in immune-mediated disease prevalence between different countries and populations which cannot be explained by genetic variability.
Aims: To compare the prevalence of antinuclear (ANA), antimitochondrial, antireticulin, liver-kidney microsomal, parietal cell, thyroid microsomal and double-stranded DNA (dsDNA) antibodies among adults aged 20-44 years in two towns, i.e. in Tartu, Estonia (n = 448) and in Uppsala, Sweden (n = 532) with a low and a high prevalence of allergy.
Methods: For autoantibody detection, standard indirect immunofluorescence tests on tissue and Chritidia lucilia antigenic preparations were used (sera were diluted starting from 1:10).
Results: The prevalence of ANA was lower in Tartu than in Uppsala (3 vs. 10% among males and 11 vs. 16% among females; p<0.01 and p<0.1, respectively). Furthermore, dsDNA antibody-positive cases were only identified in Uppsala. The largest difference between the two populations was revealed for IgM type ANA, both among males (1 vs. 6%; p<0.02) and females (5 vs. 11%; p<0.01). In addition, the antibody titers were lower in Tartu than in Uppsala (p<0.05). The prevalence of other autoantibodies was similar in the two towns.
Conclusions: The findings could support that Th2-like immune responses are commoner in Sweden than in Estonia, as previously suggested by the higher prevalence of allergy.