Measles virus (MV) causes transient but profound immunosuppression resulting in increased susceptibility to secondary bacterial and
viral infections. Due to the development of these
opportunistic infections,
measles remains the leading
vaccine-preventable cause of child death worldwide. Different immune abnormalities have been associated with
measles, including disappearance of delayed-type
hypersensitivity reactions, impaired lymphocyte and antigen-presenting cell functions, down-regulation of pro-inflammatory
interleukin 12 production and altered
interferon alpha/beta signalling pathways. Several MV
proteins have been suggested to hinder immune functions:
hemagglutinin, fusion
protein,
nucleoprotein and the non-structural V and C
proteins. This review will focus on the novel functions attributed to MV
proteins in the immunosuppression associated with
measles. Here, we highlight new advances in the field, emphasising the interaction between MV
proteins and their cellular targets, in particular the cell membrane receptors, CD46, CD150, TLR2 and FcgammaRII in the induction of immunological abnormalities associated with
measles.