Can viruses help us to understand and classify the MHC class I molecules at the maternal-fetal interface?

Placental expression of HLA-C, HLA-E, and HLA-G locus products is now well described. However, to date, the functional relevance of these MHC class I products at the maternal-fetal interface is incompletely described. We prop ose here that HLA-C, -E, and -G comprise a distinct: and cohesive group of MHC class I products. This hypothesis is supported by a growing body of dat a, including that obtained through the study of viral immune evasion. Conti nued investigation of viral interactions with MHC class I products promises to help us to define those specific attributes of HLA-C; -E, and -G that d efine their common characteristics. (C) American Society for Histocompatibi lity and Immunogenetics, 2000. Published by Elsevier Science Inc.