Killer-specific secretory (Ksp37) gene expression in subjects with Down’s syndrome

Down syndrome is characterized by dysmorphic features, mental retardation and problems of immune deficiency. Chronic infection by Epstein–Barr virus is frequently present in subjects with Down syndrome. Ksp37 gene is commonly expressed by NK, CD8⁺ T, γδ T and CD4⁺ T cells; these data suggest that Ksp37 have cytotoxic properties. An increase of Ksp37 protein serum levels it has been showed during the acute phase of Epstein–Barr virus. In this study, we evaluated the expression of Ksp37 mRNA, in fibroblasts and leukocytes of DS subjects and in normal subjects with realtime reverse transcription-PCR. This analysis shows that in fibroblasts and leukocytes of Down syndrome subjects the KSP37 gene expression was increased compared with control subjects. The results of this study suggest that the expression of Ksp37 gene might be associated with increased susceptibility of individuals with Down syndrome to EBV infections and autoimmune problems.