Possible involvement of protein kinase C activation in down-regulation of CD3 antigen on adult T cell leukaemia cells.
The role of protein kinase C (PKC) system on CD3 expression on adult T-cell leukaemia (ATL) was examined. The down-regulation of CD3 on ATL cells is reportedly induced by CD3 down-regulating factor (CD3DF) contained in serum and culture supernatants of leukaemia cells from acute type ATL patients. After we cultured normal PBMC with a PKC inhibitor, H-7, CD3DF activity for PBMC was reduced significantly. Culture with H-7 of HTLV-1 transformed T cells, ATL-2 cells whose CD3 expression had been decreased, led to enhancement of CD3 expression in a time-dependent manner. These findings suggest that CD3DF may play an important role as a PKC system activator, resulting in CD3 down-regulation.
Matsuda
M
M
Third Department of Internal Medicine, Kinki University School of Medicine, Osaka, Japan.
Maeda
Y
Y
Shirakawa
C
C
Morita
S
S
Koyama
A
A
Horiuchi
F
F
Hamazaki
H
H
Irimajiri
K
K
Horiuchi
A
A
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000187:drug effects; D017252:CD3 Complex / Q000032:analysis* / Q000187:drug effects; D015536:Down-Regulation / Q000502:physiology*; D006801:Humans; D007546:Isoquinolines / Q000494:pharmacology; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000201:enzymology / Q000276:immunology*; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000502:physiology*; D014407:Tumor Cells, Cultured
D000951:Antigens, Neoplasm; D017252:CD3 Complex; D007546:Isoquinolines; D010879:Piperazines; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C