STUDY ON THE INTRACELLULR
SIGNALING IN DIFFERENTIATION OF LEUKEMIA-DERIVED DENDRITIC DELL
Zhou
JF, Yang XQ, Li X, Wang LJ
Department of Immunology, Children’s Hospital, Chongqing,
China
Objective: To investigated the role
of intracellular signaling during leukemia differentiation to dendritic
cells.
Methods: Human promyelocytic
leukemia line HL-60 differentiates in to dendritic-like cells in response
to granulocyte-macrophage CSF (50ng/ml) plus Tumor necrosis-α (2.5ng/ml),or
phorbol ester (10ng/ml) . Internal
signal including NF-kB protein (RelA, RelB) and [Ca2+]i. RelA
protein expression was analyzed by the flow cytometery. The expression of
RelB mRNA was tested by RT-PCR and compared in differentiation stage of the
process.
Results: Constitutive expression of
RelA was found in HL-60 and up regulated by PMA within 24h or GM-CSF plus
TNF within 72h, plateaued through about 1w.RelB mRNA was absent in HL-60
and could be induced by the stimulations .Combined PMA and GM-CSF plus TNF,
the RelB mRNA expression increased then declined on 10th day.The level of
[Ca2+]i decreased significantly in differentiated cells. PMA had
no evident effect on [ Ca2+]i.
Conclusion: NF-kB is probably
important for the DC differentiation from leukemias. The synergetic effect
of calcium and PMA maybe in the process of DC differentiation.