Expression of minor histocompatibility antigen, HA-1, in solid tumor cells.
BACKGROUND
Minor histocompatibility antigen (mHag) induces and mounts graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. Among several mHags, HA-1 is one that acts alone and is the most studied. It is suggested that HA-1 may be one of the immunodominant antigens inducing not only graft-versus-host disease but also graft-versus-malignancy effects. There are some reports that mHag HA-1-specific cytotoxic T lymphocytes generated from an HA-1-negative donor can lyse HA-1-positive leukemic cells. However, the tissue distribution of HA-1 has been described as restricted to the cells of the hematopoietic lineage.


METHODS
We examined the HA-1 expression in peripheral blood mononuclear cells (PBMNC), leukemia/lymphoma cell lines, solid tumor cell lines, and paired samples of tumor and normal tissues from individual cancer patients by quantitative reverse-transcription polymerase chain reaction.


RESULTS
We found that mRNA of HA-1 is expressed in all leukemia/lymphoma cell lines and PBMNC. Most of the leukemia/lymphoma cell lines have the same levels of HA-1 expression as a leukemia/lymphoma cell line, Raji. The expression levels of human PBMNC were 14- to 19-fold higher than those of Raji. Among 32 solid tumor cell lines, 7 showed >50% expression levels compared with Raji.


CONCLUSIONS
HA-1 expression in the mRNA level is higher in cells of hematopoietic origin, but this tissue distribution is not strictly restricted. Some solid tumor cells and tissues express HA-1 gene equal to hematopoietic cells.
Fujii
Nobuharu
N
Department of Internal Medicine (II), Okayama University Medical School, Okayama, Japan. nfujii@md.okayama-u.ac.jp
Hiraki
Akio
A
Ikeda
Kazuma
K
Ohmura
Yasushi
Y
Nozaki
Isao
I
Shinagawa
Katsuji
K
Ishimaru
Fumihiko
F
Kiura
Katsuyuki
K
Shimizu
Nobuyoshi
N
Tanimoto
Mitsune
M
Harada
Mine
M
D001483:Base Sequence; D020544:Graft vs Leukemia Effect / Q000276:immunology; D006801:Humans; D007938:Leukemia / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008223:Lymphoma / Q000276:immunology; D015778:Minor Histocompatibility Antigens / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000276:immunology*; D009842:Oligopeptides / Q000235:genetics* / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
C110615:HA-1 antigen; D015778:Minor Histocompatibility Antigens; D009842:Oligopeptides