ANALYSIS OF SEQUENCE AND PATHOGENIC PROPERTIES OF 2 VARIANTS OF ENCEPHALOMYOCARDITIS VIRUS DIFFERING IN A SINGLE AMINO-ACID IN VP1

The encephalomyocarditis (EMC) virus-induced diabetes-like syndrome in mouse inbred strains was used asa model to study the insulin-dependen t diabetes mellitus (IDDM). Our investigations were performed with two EMC virus variants, PV2 and PV7. After infection of SJL mice with 10( 5) PFU of PV2 about 70% of the animals developed a diabetes-like syndr ome, whereas the PV7 infected mice appeared healthy. Histological exam ination and in situ experiments revealed that the islets of Langerhans are a main target of PV2, whereas PV7 infection leads to only modest changes of the islets. Sequence analysis of both variants revealed one amino acid exchange within the capsid protein VP1. Hence, we describe the first diabetogenic and non-diabetogenic EMCV variants differing i n only one single amino acid.