HRF20 CD59 COMPLEMENT REGULATORY PROTEIN EXPRESSION IS PHENOTYPE-DEPENDENT AND INDUCIBLE BY THE HYPOMETHYLATING AGENT 5-AZACYTIDINE ON BURKITTS-LYMPHOMA CELL-LINES/
M. Kuraya et al., HRF20 CD59 COMPLEMENT REGULATORY PROTEIN EXPRESSION IS PHENOTYPE-DEPENDENT AND INDUCIBLE BY THE HYPOMETHYLATING AGENT 5-AZACYTIDINE ON BURKITTS-LYMPHOMA CELL-LINES/, Immunology letters, 37(1), 1993, pp. 35-39
We studied the expression of the 20-kDa homologous restriction factor
(CD59/HRF20), a complement regulatory protein, on two subsets of blood
derived B cells and on Burkitt's lymphoma lines. Both low-density (ac
tivated) and high-density (resting) B cell populations expressed high
levels of CD59. CD59 was detectable, however, only on a minority of ce
lls or not at all on three Epstein-Barr virus (EBV)-negative BL lines
(BL41, BL28 and DG75) and on clones of an EBV-positive BL line (Mutu)
that phenotypically resembled resting B lymphocytes. On the other hand
, CD59 was detected at high or medium levels on Mutu cells which had a
lymphoblastoid cell-like phenotype. Expression of CD59 was up-regulat
ed by 5-azacytidine, a drug inhibiting cytosine methylation, on CD59-n
egative cell lines. Induction was accompanied by a partial hypomethyla
tion in the 5' region of CD59 coding sequences.