Cell surface expression of HLA-E molecules on PBMC from a TAP1-deficient patient.
It was recently revealed from studies on TAP-deficient cell lines that HLA-E molecules are associated with nonamer peptides derived from certain HLA class I leader sequences and are expressed on the cell surface in a TAP-dependent manner. We have previously reported a homozygous TAP1 gene mutation in a HLA class I-deficient patient. In the present report, we demonstrate HLA-E molecule expression on the surface of the peripheral blood mononuclear cells (PBMC) of the TAP1-deficient patient. The HLA-E expression level on the monocytes of the patient was as high as that in healthy donors, whereas the HLA-E expression level on the lymphocytes of the patient was slightly lower. On the other hand, HLA-E expression was not detected on KMW-B2 cells, an Epstein-Barr virus (EBV)-transformed B-cell line derived from the lymphocytes of the TAP1-deficient patient. These data suggest the existence of TAP-dependent and -independent pathways for the surface expression of HLA-E molecules.
Furukawa
H
H
Department of Research, Japanese Red Cross Central Blood Center, Tokyo.
Yabe
T
T
Akaza
T
T
Tadokoro
K
K
Tohma
S
S
Inoue
T
T
Tokunaga
K
K
Yamamoto
K
K
Geraghty
D E
DE
Juji
T
T
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000502:physiology*; D018941:Antigens, CD19 / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D017252:CD3 Complex / Q000032:analysis; D002460:Cell Line; D002472:Cell Transformation, Viral; D006680:HLA Antigens / Q000096:biosynthesis*; D004854:Herpesvirus 4, Human; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D008285:Major Histocompatibility Complex / Q000235:genetics / Q000502:physiology*; D013499:Surface Properties; D000097625:HLA-E Antigens
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D018941:Antigens, CD19; D017252:CD3 Complex; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D018950:Lipopolysaccharide Receptors; D000097625:HLA-E Antigens; C073119:TAP1 protein, human; C071692:TAP2 protein, human