Abstracts (complete list) - Wissenschaft Online

Daniel Schaefer, Anja Janysek, Jürgen Neumann, Norbert Koch
Strong impact of invariant chain on surface expression of HLA-
DQ
Daniel Schaefer, Anja Janysek, Jürgen Neumann and Norbert Koch
Division of Immunobiology, Institute of Genetics, University of Bonn
MHC class II molecules are peptide receptors presenting peptides from extra cellular
antigens on the cell surface of antigen-presenting cells. The peptide receptors are
composed of alpha and beta subunits, which assemble in the ER with invariant chain
(Ii). The HLA class II region encodes alpha and beta subunits of three different isotypes:
DP, DQ and DR. In this study we examined the impact of Ii on intracellular transport
and surface expression of HLA class II isotypes. We inspected various combinations of
alpha and beta chain isotypes for transport and surface expression by employing
western blotting, immunofluorescent staining and FACS-analysis. In contrast to DR and
DP isotypes, surface expression of DQ heterodimers strictly depends on Ii.