C. Behrendt et al., Up-regulated perforin expression of CD8(+) blood lymphocytes in generalized non-anaphylactic drug eruptions and exacerbated psoriasis, EUR J DERM, 10(5), 2000, pp. 365-369
Perforin expressed in CD8(+) cytotoxic T cells is known to mediate the lysi
s of target cells carrying microbial as well as tumor-associated antigens,
and to be involved in autoimmune and transplant reactions. The aim of the p
resent investigation was to study the role of perforin- and CD8-expressing
effector lymphocytes from peripheral blood in patients with generalized inf
lammatory skin diseases. Mononuclear cells were separated from peripheral v
enous blood and permeabilized by 0.1% saponin. The co-expression of cytopla
smatic perforin and cell membrane-residing CD8 was determined in lymphocyte
s by immune-flow cytometry. Patients affected by generalized macular-papula
r drug eruptions (n = 14), drug-unrelated acute urticaria (n = 10) and drug
-independently exacerbated psoriasis (n = 11, PASI scores ranging from 25 t
o 35), as well as control individuals not affected by any inflammatory skin
disease (n = 10) were enrolled. Additionally, n = 5 patients with drug-ind
uced Stevens-Johnson syndrome (SJS) were included. The average proportion o
f CD8(+) peripheral lymphocytes co-expressing perforin in generalized drug
eruptions (68.8 +/- 24.9%) and exacerbated psoriasis (67.2 +/- 17.1%) diffe
red significantly from the controls (43.5 +/- 11.6%; p less than or equal t
o 0.05), whereas no significant difference for acute urticaria (58.2 +/- 23
.1%) could be measured. In each of the 5 SJS patients treated by high dose
systemic steroids the parameter substantially declined during the first 7 d
ays after admission from an average value of 81.6% down to 33.0%. Thus, as
compared to controls we observed an increased perforin(+) proportion of CD8
(+) lymphocytes in generalized drug eruptions and in exacerbated psoriasis
but not in acute urticaria. Therefore the parameter showed some specificity
as a marker of distinct inflammatory skin disorders, and proved to be usef
ul in monitoring the disease activity of SJS under anti-inflammatory medica
tion. Furthermore, the findings point to a possible crucial role of CD8(+)
lymphocytes in the pathogenesis of psoriasis.