Comprehensive analysis of FOXP3 mRNA expression in leukemia and transformed cell lines.
Studies of FOXP3 expression have thus far focused on T cells, including both normal and malignant T cells. In particular, adult T cell leukemia/lymphoma (ATLL) cells have been studied intensively because their phenotype resembles that of normal CD4(+)CD25(+) regulatory T (Treg) cells. However, a comprehensive study of FOXP3 expression covering all hematopoietic cell lineages has not yet been performed. In this study, FOXP3 mRNA expression was examined by quantitative PCR using a large collection of human hematopoietic cell lines derived from leukemia/lymphoma or virus-transformation, including cells lines with T, B, plasmacytoid, myeloid, monocytic, megakaryocytic, erythroid, and NK lineages. Unexpectedly, we found FOXP3 mRNA expression in a number of cell lines belonging to all of the cell lineages investigated. In sharp contrast, FOXP3 protein expression was found in only three cell lines, all of which were HTLV-I-infected. Several non-T cell lines expressed higher levels of mRNA but were still negative for protein expression. The broad mRNA expression contrasts with the restricted protein expression of FOXP3 in human hematopoietic cell lines, suggesting that post-transcriptional control mechanisms may control FOXP3 protein expression.
Yamamoto
Mayuko
M
Cell Biology Institute, Research Center, Hayashibara Biochemical Laboratories Inc., 675-1 Fujisaki, Okayama 702-8006, Japan. m_yamamoto@hayashibara.co.jp
Tsuji-Takayama
Kazue
K
Suzuki
Motoyuki
M
Harashima
Akira
A
Sugimoto
Akira
A
Motoda
Ryuichi
R
Yamasaki
Fumiyuki
F
Nakamura
Shuji
S
Kibata
Masayoshi
M
D015153:Blotting, Western; D002461:Cell Line, Transformed / Q000378:metabolism* / Q000473:pathology; D019070:Cell Lineage; D002478:Cells, Cultured; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000235:genetics*; D015973:Gene Expression Regulation, Leukemic; D015368:Human T-lymphotropic virus 1 / Q000235:genetics; D006801:Humans; D007938:Leukemia / Q000235:genetics* / Q000473:pathology; D008223:Lymphoma / Q000235:genetics* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D012333:RNA, Messenger