Down-regulation of IL-10 transcript levels and protein
expression by TSA. (A) Increasing concentrations of TSA
(0–1,000 ng/ml) progressively decrease the amount of
IL-10 mRNA relative to GAPDH mRNA.
(B) Based on densitometric scanning of the gel in
A, this graph quantifies the percent change in
IL-10 transcript levels with increasing concentrations
of TSA over 24 h. These data are representative of nine SLE
subjects studied. T cells from normal controls do not express
detectable IL-10 mRNA. (C)
IL-10 and GAPDH transcripts from T cells
of three SLE subjects are shown. Transcripts from freshly isolated T
cells are shown in lanes 1, 4, and 7. Transcripts from T cells cultured
for 18 h in the absence or presence of 1,000 ng/ml TSA are shown
in lanes 2, 5, and 8 and 3, 6, and 9, respectively. These data are
representative of nine SLE subjects studied. (D) Based
on densitometric scanning of gels, this graph shows the percent change
in amount of IL-10 mRNA from SLE T cells cultured in the
absence or presence of 1,000 ng/ml TSA. (E) This graph
illustrates the inhibition of IL-10 secretion by increasing
concentrations of TSA over 24 h. (F) This graph
depicts the percent change of IL-10 secretion over time. IL-10 protein
secretion was undetectable in supernatants from normal T cells.
Statistical analysis was performed by paired Student's
t test.