HLA-DR ALLELES IN PATIENTS WITH SJOGREN'S SYNDROME OVER-REPRESENTING V{beta}2 AND V{beta}13 GENES IN THE LABIAL SALIVARY GLANDS

To identify genetic factors that play a role in the pathogenesisof patients with SS over-representing Vß2 and Vß13genes in the lips, HLA-DR and -DQ alleles of 10 primary SS patientswith predominant expression of Vß2 and Vß13genes in the lips were analysed, using the polymerase chainreaction (PCR) and sequence specific oligonucleotide probes.The CDR3 amino acid sequences of cDNA clones encoding Vß2and Vß3 genes were also determined by PCR. The resultsshowed that the DRB4^*0101 allele was significantly increased(80%) and that the frequency of DRB3 allele was decreased (0%)when compared to findings in healthy subjects (35.6 and 26%,respectively). Sequencing analyses demonstrated that 75% ofVß2 cDNA clones and 87% of Vß13 cDNA cloneshad a glutamine residue at position 106, in the CDR13 region.Moreover, the conserved sequences (Y^*TLRNEQ) in the CDR3 ofVß13-positive T cell were detected in two differentclones (27%) from the two individual SS patients. These findingssuggest that the decreased DRB3 and increased DRB4^*0101 allelesmay be associated with the antigens recognized by Vß2-and Vß13-positive T cells. KEY WORDS: HLA, Sjögren's syndrome, TCR Vß, CDR3 region