We studied the constitutive and the interferon (IFN)-γ-induced expression of HLA class I antigen heavy chain, β2-microglobulin (β2m), TAP-1, TAP-2 and tapasin in a panel of eleven neuroblastoma cell lines. Surface expression of HLA class I antigens was low in eight out of eight neuroblastoma cell lines bearing MYC-N amplification and/or 1p deletion, while two out of three neuroblastoma cell lines lacking these genetic alterations showed normal expression. IFN-γ treatment restored HLA class I antigen surface expression in all neuroblastoma cell lines. Eight out of 11 neuroblastoma cell lines did not express TAP-1 mRNA and three of them also lacked TAP-2 mRNA. β2 m mRNA was barely detectable or absent in five neuroblastoma cell lines, while tapasin mRNA was always expressed. IFN-γ upregulated the expression of HLA class I heavy chain, β2 m, TAP-1, TAP-2 and tapasin, as detected at mRNA or protein level. Post-transcriptional events were involved in altered TAP-1 and β2 m expression in one peculiar neuroblastoma cell line. These data indicate that multiple mechanisms play a role in the HLA class I antigen-deficient phenotype of human neuroblastoma.
|Number of pages||8|
|Publication status||Published - 2001|
- HLA class I
ASJC Scopus subject areas
- Cell Biology