Coexpression of cell-surface immunoglobulin (sIg), terminal deoxynucleotidyl transferase (TdT) and recombination activating gene 1 (RAG-1): two cases and derived cell lines.
While it is generally agreed that in the lymphoid differentiation of B lineage cells there is no stage in which cell-surface immunoglobulin (sIg) and terminal deoxynucleotidyl transferase (TdT) are expressed simultaneously, a few B cell acute lymphoblastic leukemia (B-ALL) cases with this phenotype have been reported. Two such cases and the derived cell lines are reported here, in which the expression of recombination activating gene-1 (RAG-1) was also detected. One case was a CD19+ CD22+ HLA-DR+ sIg+ (gamma, kappa) B-ALL. The cell line (Bay9I) also expressed CD10. Karyotypic analysis revealed t(14;18)(q32;q21) and additional aberrations. In the other case, the fresh leukemia cells expressed CD19, CD24 and HLA-DR antigen. The derived cell line (Tree92) also expressed CD22 and sIg (mu, lambda). The karyotype of the Tree92 cells was t(8;14)(q24;q32) with additional aberrations. Tree92 is the first established cell line having both t(8;14)(q24;q32) and TdT. TdT was detected by Northern blotting as well as indirect immunofluorescence analysis. In addition, both Bay9I and Tree92 expressed RAG-1, as detected by Northern blot analysis. Cross-linking of sIg on Tree92 cells with anti-mu antibody led to significant down-regulation of RAG-1 expression. It seems that there is a sIg+ TdT+ RAG-1+ B lineage differentiation stage, and that signaling through sIg can modulate RAG-1 expression.
Nakamura
F
F
Department of Laboratory Medicine, Kobe University School of Medicine, Japan.
Tatsumi
E
E
Tani
K
K
Kumagai
S
S
Kosaka
Y
Y
Sano
K
K
Nakamura
H
H
Nesumi
N
N
Abe
T
T
Koiwai
O
O
D000328:Adult; D015703:Antigens, CD / Q000378:metabolism; D000954:Antigens, Surface / Q000378:metabolism; D015152:Blotting, Northern; D002051:Burkitt Lymphoma / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D002462:Cell Membrane / Q000276:immunology; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D002898:Chromosomes, Human, Pair 8; D004253:DNA Nucleotidylexotransferase / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D015973:Gene Expression Regulation, Leukemic; D018398:Homeodomain Proteins; D006801:Humans; D007136:Immunoglobulins / Q000378:metabolism*; D007223:Infant; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D014178:Translocation, Genetic
D015703:Antigens, CD; D000954:Antigens, Surface; D018398:Homeodomain Proteins; D007136:Immunoglobulins; D011506:Proteins; D012333:RNA, Messenger; C064658:RAG-1 protein; D004253:DNA Nucleotidylexotransferase