Hungarian Immunology

[Autoimmunity as a result of escape from RNA surveillance]

SEMSEI Imre, DARISE Farris, BACHMANN Michael

JANUARY 20, 2007

Hungarian Immunology - 2007;6(01-02)

[The pathomechanisms of autoimmune diseases are still unknown. Numerous factors are thought to play a role in the formation of the diseases (genetic arrangement, hormonal factors, exogen and endogen viruses, etc.) and many hypotheses have been formulated to explain the role of these factors. Most of the theories suspect that disturbance of the immune system is the clue but according to other researchers the immune system performs properly and one has to find other alterations that could be blamed for the formation of the autoimmune diseases. The aim of our present work is to show that certain genetic alterations together with the mistake of the RNA surveillance system could lead to autoimmune reactions. Results of immune research conducted in the past two decades revealed that there are mutations in the hot spot region of exon 7 of the La gene in the peripheral lymphocytes of patients suffering from certain autoimmune diseases (Sjögren's syndrome, SLE). RNAs originated from the mutant gene contain premature termination codon and therefore the RNA surveillance mechanism should get rid of these RNAs in order to prevent the formation of mutant proteins. However, because of the mistake of the surveillance system mutant proteins are formed that could finally lead to the autoimmune reactions.]

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