Objective   To analyze the subcellular distribution of Chinese rhesus macaques’ major histocompatibility complex (MHC) class Ⅰ molecules and to prepare a cell line suitable for study on their expression and antigen presentation potential in vitro.    Methods   An eukaryotic expression vector pEGFP-N1 harboring the Mamu-B*1703 heavy chain gene was transfected into K562 (human chronic myelogenous leukemia) and B16 cells (mouse melanoma). The cells were collected and stained with W6/32 monoclonal antibody or Mamu-B*1703 antiserum followed by PE-conjug

ated second antibody staining. Distribution of recombinant Mamu-B*1703 molecules were observed with inverted laser confocal microscopy and further analyzed by flow cytometry.    Results   Green-fluorescence was observed in the cytoplasm of both K562 and B16 cells after excitation. This indicated that transfected Mamu-B*1703 heavy chain gene

which was fused with EGFP sequence

could be expressed in both the cells. But only on the surfaces of K562 cells

instead of on that of B16 cells

Mamu-B*1703 complexes were displayed as indicated by phycoerythrin-conjugated antibodies to MHC class Ⅰ complexes.   Conclusion   The heavy chain of Mamu-B*1703 assembles with human β

2

m molecules in K562 cells to form a complex that is transported onto cell surfaces. Such an assembly or transport process is unlikely to occur in B16 cells.