A mutation determining the loss of HLA-A2 antigen expression in a cervical carcinoma reveals novel splicing of human MHC class I classical transcripts in both tumoral and normal cells

The major histocompatibility complex (MHC) is a large multigene complex encoding the highly polymorphic class I and II MHC molecules. The molecules are broadly distributed in different tissues and their cell surface expression is essential for immune recognition of both virally infected and transformed neoplastic cells. However, the level of MHC class I cell surface expression is frequently modulated in both cases and the resulting variation in expression may contribute to the failure of cellular immune effectors in surveillance (Garrido et al. 1995, 1997; Ploegh 1998).