Differential transport requirements of HLA and H-2 class I glycoproteins.
Transport of human and mouse major histocompatibility complex class I glycoproteins has been examined in a transport deficient B-lymphoblastoid cell line X T-lymphoblastoid cell line (B-LCL X T-LCL) hybrid, 174 X CEM.T2 (T2). This cell line expresses no detectable endogenous HLA-B5 and reduced levels of HLA-A2 on its surface although these molecules are synthesized. In order to study this defect further, either HLA-Bw58 or HLA-B7 genomic clones were transfected into T2. Metabolic labeling and immune precipitation demonstrated biosynthesis of the Bw58 or B7 glycoprotein. However, like the endogenous HLA-B5 molecule, neither HLA-Bw58 nor HLA-B7 was expressed at the cell surface. The cloned genes were properly expressed on the surface of C1R, a control B-LCL. To determine if mouse class I alleles had the same transport requirements as the human class I glycoproteins, either mouse H-2Dp or H-2Kb class I genes were introduced into T2. Surprisingly, the H-2 class I glycoproteins were transported to the cell surface normally. These data suggest a fundamental difference between human and mouse histocompatibility antigens in their requirements for intracellular transport.
Alexander
J
J
Department of Microbiology and Immunology, Duke University Medical Center, Durham, NC 27710.
Payne
J A
JA
Murray
R
R
Frelinger
J A
JA
Cresswell
P
P
D000818:Animals; D001692:Biological Transport; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D005805:Genes, MHC Class I; D006183:H-2 Antigens / Q000235:genetics*; D006680:HLA Antigens / Q000235:genetics*; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D014157:Transcription Factors / Q000235:genetics; D014162:Transfection
D006183:H-2 Antigens; D006680:HLA Antigens; D008562:Membrane Glycoproteins; D014157:Transcription Factors