LACK OF HLA-G SOLUBLE ISOFORMS IN GRAVES-BASEDOW THYROCYTES AND COMPLETE CDNA SEQUENCE OF THE HLA-G-ASTERISK-01012 ALLELE

The presence of HLA-G mRNA has been studied in thyroid follicular cell s from autoimmune patients with Graves' disease. Investigating the pos sible role of the expression of the HLA-G gene in tissue inflammation, we have found four of the six HLA-G mRNA isoforms described: G1, G2, G3 and G4, but not the soluble ones G5 and G6. Soluble G isoforms may be responsible for inducing tolerance and inflammation control and the ir absence in autoimmune thyroid follicular cells may induce failure o f such control. In addition, the complete coding sequence of HLA-G010 12 has been obtained from thyrocytes and it shows only four synonymous changes with respect to the HLA-G01011 allele; this further supports the existence of an evolutionary pressure for invariance on HLA-G gen es.