Reduction of the fraction of circulating helper-inducer T cells identified by monoclonal antibodies in psoriatic patients treated with long-term psoralen/ultraviolet-A radiation (PUVA)

Ultraviolet radiation has been found to alter the distribution and function of human lymphocytes. To determine whether photochemotherapy (PUVA) alters circulating levels of T cell subset marker-bearing lymphocytes, cells from 9 patients with psoriasis undergoing PUVA therapy for several years (mean 4.6 +/- 1.4 yr), 17 patients with active untreated psoriasis, and 20 healthy volunteers were reacted with monoclonal antibodies to T cell surface markers, including OKT3 (all peripheral blood T cells), OKT4 (helper/inducer T cells), OKT6 (common thymocytes), and OKT8 (suppressor/cytotoxic T cells), and analyzed by flow cytometry. There were no differences in the distribution of T cell subsets between healthy volunteers and patients with active psoriasis. In contrast, the percentages of lymphocytes reacting with OKT3 and OKT4 were lower (by 16% and 12% percent respectively, p less than 0.0025) in the PUVA-treated patients compared to healthy volunteers or patients with active psoriasis that had not received PUVA therapy. There was no difference in the percentage of OKT8 and OKT6 bearing cells. Squamous cell carcinoma of the skin subsequently developed in 2 of 3 PUVA-treated patients with the lowest percentages of T4-bearing cells. These findings indicate that long-term PUVA therapy is associated with a reduction in circulating helper/inducer T cells. This reduction may have a role in the altered immune function reported in PUVA-treated patients.     

Stimulation of T cells by autologous mononuclear leukocytes and epidermal cells in psoriasis

Summary Based on reports suggesting aberrant cell-mediated immunity and altered infiltration of immunocompetent cells into the skin in psoriasis, we studied the stimulation of T cells by autologous non-T mononuclear leukocytes (autologous mixed lymphocyte reaction, AMLR) and by epidermal cells isolated from lesional and clinically uninvolved skin in psoriasis (autologous mixed epidermal cell lymphocyte reaction, AMECLR). Age- and sex-matched individuals served as controls. We found that the AMLR in psoriasis (n=11) was similar to that in healthy controls (n=16); furthermore, cell proliferation was alike in the presence of either 5% AB-serum or autologous serum. By contrast, while the AMECLR in healthy controls (n=9) resembled that in psoriatics employing epidermal cells from univolved skin, epidermal cells from lesional sites (n=10) induced a significantly higher proliferation of autologous T cells in the AMECLR (P<0.01). We conclude that the in vitro stimulation of T cells by non-T mononuclear leukocytes is normal in psoriasis and is not regulated by autologous serum. Lesional psoriatic epidermal cells, however, are more active in stimulating autologous T cell proliferation than cells from univolved psoriatic or normal epidermis.     

Estimation of tissue osteopontin levels before and after different traditional therapeutic modalities in psoriatic patients

Background Several lines of evidences support a major role for Th1 cells in psoriasis. Treatment of psoriasis with cyclosporine, methotrexate and psoralen plus ultraviolet A (PUVA) is associated with clinical improvement and decrease in epidermal hyperplasia. Osteopontin (OPN) exerts a T‐helper type 1 (Th1) cytokine function, regulating inflammatory cell accumulation and function. Objective To detect the effects of methotrexate, cyclosporine and PUVA on OPN expression in psoriatic plaques, and whether these changes correlate with clinical response. Methods For three groups of psoriatic patients (each including 12 patients), the Psoriasis Area Severity Index (PASI) and levels of lesional skin OPN were determined using enzyme‐linked immunosorbent assays before and after treatment with methotrexate, cyclosporine or PUVA. Skin biopsies from 20 healthy volunteers served as control for OPN levels in normal skin. Results Baseline lesional skin of psoriatic patients showed a statistically significant elevation of OPN levels in comparison to controls. Three months after therapy, the three therapeutic modalities were associated with a significant decrease in the mean levels of PASI and tissue OPN, with the PUVA group showing the highest level of reduction in OPN levels and cyclosporine group showing the highest level of reduction in PASI. Conclusion Our study points to the possible role played by OPN in the pathogenesis of psoriasis and in reflecting disease severity. These standard therapeutic modalities used in the current study were associated with a significant decrease in PASI and OPN levels. They constitute highly effective therapeutic modalities for psoriasis, which might exert their anti‐psoriatic activity partially through altering the expression of OPN.     

Antibodies eluted from lymphoid cell membrane. Occurrence in certain varieties of scleroderma.

By means of acid elution two antibodies could be removed successfully from the circulating lymphocytes of 11 patients with certain varieties of scleroderma. One was specifically directed against nuclear antigen(s) of endothelial cells (NEC) of the dermal blood vessels, and another against nuclear antigen(s) of epidermal basal cells (NBC) of the involved and uninvolved skin of the patients. In two cases of acroscleroderma, the eluates failed to react with either endothelial or basal cells of involved or uninvolved skin. In none of 20 healthy controls involved in this study could an antibody be eluted from the circulating lymphocytes. The aforementioned antibodies do not bind complement in vitro and do occur in the serum of four patients. Circulating antinuclear antibody (speckled type) was detectable in two cases of scleroderma.     

Erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA

In PUVA treatment of psoriasis, clinical observation suggests that uninvolved skin is more susceptible to PUVA erythema than lesions of psoriasis. If this is the case, then the efficacy of PUVA treatment might be increased by using localized high-dose UVA restricted to lesional skin. We have therefore studied the erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA and, for comparison, the erythemal response to UVB. In 14 patients, an area of psoriasis and adjacent uninvolved skin were exposed to a series of UVA doses (350 ± 30 nm, 1–16 J/cm²), using an irradiation monochromator. Six other patients were similarly phototested with a series of UVB doses (300 ± 5 nm, 20–112 mJ/cm²) to both uninvolved and lesional skin. Erythema was judged visually at 72 h for psoralen–UVA, and at 24 h for UVB, and measured using a scanning laser–Doppler velocimeter. In 10 patients, PUVA therapy using high-dose UVA was subsequently given to lesional skin (8–16 J/cm² twice weekly) in addition to conventional whole-body PUVA. For psoralen–UVA, the minimal phototoxic dose within psoriasis was increased by a factor of 4 compared with non-lesional skin (P < 0.01, Wilcoxon signed-rank test). For UVB, the minimal erythema dose within psoriasis was higher than that for non-lesional skin (medians > 112 and 28 respectively, P < 0.05). Laser–Doppler measurements confirmed that the reduced erythemal sensitivity was not due to masking of response by pre-existing increased blood flux within psoriasis. In six patients, the sites subsequently treated twice weekly with PUVA, using high-dose UVA, cleared faster (median number of treatments 3), but with a similar cumulative UVA dose, compared with adjacent lesional skin treated with conventional PUVA (median number of treatments 12). This study demonstrates that psoriasis may clear rapidly, without burning, using high-dose UVA. Availability of a suitable irradiation apparatus would allow rapid and effective PUVA treatment to be used for localized, resistant disease.     

Insulin‐like growth factor‐1 in psoriatic plaques treated with PUVA and methotrexate

Background The pathogenesis of psoriasis is thought to depend on the activation of immune cells and their secreted cytokines, chemokines and growth factors like IGF‐1 which may contribute to the epidermal hyperplasia of psoriasis. Treatment of psoriasis with PUVA and methotrexate are associated with clinical improvement and decrease in epidermal hyperplasia. Objective To examine the effects of PUVA and methotrexate therapy on IGF‐1 expression in psoriatic plaques and whether this change correlates with clinical response. Methods For 24 psoriatic patients, the PASI score and levels of lesional IGF‐1 and its mRNA were determined by RT‐PCR before and after treatment with either methotrexate or PUVA. Skin biopsies from 12 healthy volunteers served as control for IGF‐1 levels in normal skin. Results Lesional skin of psoriatic patients showed a statistically significant elevation in IGF‐1 and its mRNA levels in comparison to control (P = 0.0001). Both methotrexate and PUVA treatment were associated with a significant decrease in both PASI scores and lesional IGF‐1 after 10 month treatment. Conclusion Both methotrexate and PUVA therapy for psoriasis are associated with a decrease in PASI score and IGF‐1. The IGF‐1 down‐regulation may possibly be a consequence of the decrease in cytokines and inflammatory cellular infiltrate that occur following treatment with either modalities or due to their effect on local fibroblast activity and proliferation.     

Immunological effects of stress in psoriasis

Background Psychological stress causes phenotypic changes in circulating lymphocytes and is regarded as an important trigger of the Th1‐polarized inflammatory skin disease psoriasis. Objective To study the effects of psychological stress on immunological parameters, i.e. membrane molecules relevant to the pathophysiology of psoriasis, especially cutaneous lymphocyte‐associated antigens (CLA) involved in T and natural killer (NK) cells homing in on the skin. Methods The severity of psoriasis was assessed in patients using the Psoriasis Area and Severity Index. Patients with psoriasis (n = 15) and healthy volunteers (n = 15) were exposed to brief psychological stress in the laboratory. In vitro analyses were conducted 1 h before, immediately following and 1 h after stress exposure. Peripheral T‐ and NK‐cell subsets including CD8+ T lymphocytes, CLA+ lymphocytes and lymphocyte function‐associated antigen type 1 (LFA‐1)+ lymphocytes were analysed by flow cytometry. Results We found a significant stress‐induced increase of CD3+ T lymphocytes in patients with psoriasis only. Analyses of T‐cell subsets revealed that this increase was observable for cytotoxic CD8+ T lymphocytes and CLA+ CD3+ lymphocytes. The total number of circulating NK cells (CD16+, CD56+) increased immediately after stress in both groups whereas only patients with psoriasis showed a significant increase in CLA+ NK cells. Conclusions A higher stress‐induced increase of CLA+ T and CLA+ NK cells in the circulation of patients with psoriasis might point to an increased ability of T and NK cells in the presence of psoriasis to home in on the skin during mental stress. Further studies are needed to verify these relationships in more detail and to investigate the time point at which these cells accumulate within lesional skin, and whether or not psychotherapy improves the quality of life of patients with psoriasis and influences stress‐dependent parameters.     

Skewed distribution of natural killer cells in psoriasis skin lesions

Psoriasis is a hyper‐proliferative disease of the skin in which immunological mechanisms play a direct pathogenetic role. There have been limited studies of natural killer (NK) cells in psoriasis. The aim of this study was to examine the phenotype of NK cells in skin biopsies and peripheral blood mononuclear cells from patients with psoriasis and healthy controls. CD56⁺CD16^? and CD56⁺CD16⁺ NK cells were isolated from lesional skin, unaffected skin and PBMC of psoriasis patients, and normal skin and PBMC from healthy controls. The expression of CD57, NKG2A and NKG2C was assessed by flow cytometry. NK cells in psoriasis skin lesions were skewed in their expression of CD57, a marker of NK cell maturity, with CD57 expression significantly reduced and NKG2A expression increased on NK cells in lesional and unaffected skin compared to controls. These data suggest that in this patient cohort, NK cells could be isolated from psoriasis lesions and exhibit an immature phenotype.     

RNA, DNA, and cell surface characteristics of lesional and nonlesional psoriatic skin

We have measured the RNA and DNA content and examined cell surface characteristics of human epidermal cells derived from normal skin, and lesional and nonlesional areas of psoriatic skin prior to and following treatment on a modified Goeckerman protocol. Our results show that cells from active psoriatic lesions contain greater numbers of basal keratinocytes when compared with either nonlesional skin from the same patients or skin from healthy volunteers and individuals with other inflammatory skin lesions. Follow-up measurements 2-3 weeks after the initiation of therapy showed that the numbers of basal keratinocytes in resolving psoriatic lesions had decreased and approached normal levels. Multiparameter RNA/DNA flow cytometric analysis on parallel samples from the same psoriasis patients revealed an increased growth fraction and proportion of cycling cells in both the nonlesional and lesional skin compared with controls. Furthermore, the cellular RNA content was elevated in lesional psoriatic skin when compared with either nonlesional or normal skin. Flow cytometric examination of nonlesional and lesional epidermal cells obtained 2-3 weeks after the commencement of therapy revealed that the growth fraction and mean RNA content of the keratinocytes from resolving psoriatic plaques decreased in response to therapy. In contrast, the proportion of keratinocytes within the S + G2 + M phases of the cell cycle remained elevated. These data indicate that "uninvolved" psoriatic skin exhibits characteristics more closely resembling lesional psoriatic skin than normal skin. The results further suggest that quantitation of cellular RNA content and basal cell number might be sensitive indicators of early treatment response in psoriasis.     

Bath psoralen+ultraviolet A photochemotherapy vs. narrow band‐ultraviolet B in psoriasis: a comparison of clinical outcome and effect on circulating T‐helper and T‐suppressor/cytotoxic cells

Background: Comparative success rates of bath psoralen+ultraviolet A (PUVA) and narrow band‐ultraviolet B (NB‐UVB) in psoriasis treatment are variably reported with no previous studies on the possible effect of bath PUVA on circulating CD4+ and CD8+ T cells. Objective: We aimed to compare the effect of bath PUVA and NB‐UVB clinically and on circulating T‐helper and T‐suppressor/cytotoxic cells in psoriasis. Patients and methods: Thirty‐four psoriatic patients divided into a bath PUVA‐treated group (18 patients) and a NB‐UVB‐treated group (16 patients) were compared regarding the disease severity by psoriasis area and severity index (PASI) score and percentage of circulating CD4+ and CD8+ T cells by flowcytometry before and after treatment. Results: After treatment, the bath PUVA group showed a significantly higher reduction of PASI score (85.44%) than the NB‐UVB group (58.72%). Mean peripheral CD4+ T‐cell percentage was significantly lower after [36.8; 95% confidence interval (CI) 33.80, 39.97] compared with before treatment (42.06; 95% CI 38.29, 45.83) (P<0.05) in the bath PUVA group while this difference was insignificant in the NB‐UVB group (P>0.05). Conclusion: Bath PUVA therapy is superior to NB‐UVB in the treatment of moderate and severe psoriasis with mild reversible side effects. Both modalities have a systemic effect decreasing peripheral CD4+ T cells, which is more with bath PUVA.     

角质形成细胞生长因子及神经细胞生长因子在银屑病患者皮损中的表达

目的 探讨角质形成细胞生长因子(KGF)及神经细胞生长因子(NGF)与银屑病的关系及银屑病皮损中间质细胞与角质形成细胞的相互作用。方法 应用免疫组化技术分别检测33例银屑病患者皮损、8例非皮损和13例正常人皮肤中KGF、KGF受体、NGF、NGF受体的表达。结果 KGF、KGF受体在银屑病患者基底层和棘细胞下层有极强的表达,与非皮损组及正常对照组间差异有显着性(P<0.05),而非皮损组与正常对照组间差异无显着性(P>0.05).KGF、KGF受体在真皮层未见表达。NGF、NGF受体则主要表达在颗粒层和棘细胞上层,皮损组与非皮损组之间及非皮损组与正常组之间均差异有显着性(P<0.05)。结论 银屑病患者皮损中KGF及NGF可能介导了角质形成细胞的增殖与分化不全;银屑病皮损中存在着间质细胞和角质形成细胞相互作用的紊乱。     

Increased mast cell expression of PAR‐2 in skin inflammatory diseases and release of IL‐8 upon PAR‐2 activation

Please cite this paper as: Increased mast cell expression of PAR‐2 in skin inflammatory diseases and release of IL‐8 upon PAR‐2 activation. Experimental Dermatology 2010; 19: 117–122. Abstract: Mast cells are increasingly present in the lesional skin of chronic skin inflammatory diseases including psoriasis and basal cell carcinoma (BCC). It has previously been shown that proteinase‐activated receptor (PAR)‐2 is expressed by mast cells, and tryptase is a potent activator of this receptor. In this study, skin biopsies from both healthy‐looking and lesional skin of patients with psoriasis and superficial spreading BCC were collected and the expression of PAR‐2 immunoreactivity in tryptase‐positive mast cells was analysed. PAR‐2 expression was confirmed in vitro in different mast cell populations. Cord‐blood derived mast cells (CBMC) were stimulated with a PAR‐2 activating peptide, 2‐furoyl‐LIGRLO‐NH₂. Consequently, IL‐8 and histamine production was analysed in the supernatants. We observed a significant increase in the percentage of mast cells expressing PAR‐2 in the lesional skin of psoriasis and BCC patients compared with the healthy‐looking skin. HMC‐1.2, LAD‐2 and CBMC mast cells all expressed PAR‐2 both intracellularly and on the cell surface. CBMC activation with the PAR‐2 activating peptide resulted in an increased secretion of IL‐8, but no histamine release was observed. Furthermore, both PAR‐2 and IL‐8 were co‐localized to the same tryptase‐positive mast cells in the lesional BCC skin. These results show that mast cells express increased levels of PAR‐2 in chronic skin inflammation. Also, mast cells can be activated by a PAR‐2 agonist to secrete IL‐8, a chemokine which can contribute to the progress of inflammation.     

IL-4 expression by neutrophils in psoriasis lesional skin upon high-dose UVB exposure

BACKGROUND: Upon a single high dose of UVB irradiation of psoriatic lesional skin, IFN-gamma expression is decreased, whereas IL-4 expression is enhanced. A similar type 1 to type 2 shift was found in dermal T cells derived from irradiated lesional skin as compared to unexposed lesional psoriatic skin. We have found recently that the IL-4 protein detected in situ upon UVB exposure of normal skin was not associated with T cells but with infiltrating neutrophils. OBJECTIVE: To determine which cell types express IL-4 in psoriatic skin after UVB irradiation. METHODS: Skin biopsies were obtained from healthy controls and psoriasis patients before and after local UVB exposure. Double immunohistochemical stainings were performed to determine the identity of IL-4-expressing cells. RESULTS: In the irradiated skin of both healthy controls and patients, IL-4-positive cells coexpressed elastase and CD15, but not CD3. CONCLUSION: IL-4-expressing cells found in psoriatic skin after a single high-dose UVB exposure appeared to be neutrophils.     

Interleukin-8 immunoreactivity in the skin of healthy subjects and patients with palmoplantar pustulosis and psoriasis.

Previous studies have shown that neutrophil-activating peptide 1/interleukin-8 (IL-8) is present in psoriatic scales and to a lesser extent in normal human epidermis. A panel of monoclonal antibodies and polyclonal antisera raised against IL-8 was used to localize IL-8 with immunoperoxidase techniques in non-lesional and lesional skin of patients with psoriasis and palmo-plantar pustulosis (PPP), and in corresponding sites from healthy subjects. Intracellular IL-8 immunoreactivity was found in all epidermal cell layers in biopsies of healthy subjects and in non-lesional and lesional skin in both PPP and psoriasis. The most intense immunolabeling was regularly found in the basal cell layer. Intercellular epidermal IL-8 immunolabeling was regularly detected in lesional biopsies in PPP and psoriasis, but not in healthy subjects or non-lesional skin in PPP and psoriasis. No intercellular immunolabeling was detected after successful treatment of lesional skin. The majority of cells along the eccrine sweat glands, dermal mononuclear cell infiltrates, and endothelial cells were IL-8 immunoreactive in all biopsies studied. The present study suggests that IL-8, its precursor form, or, alternatively, a degradation product is present in normal human epidermis.     

Barrier repair in chronic plaque-type psoriasis

Purpose: To investigate barrier repair after mild trauma in lesional skin of psoriasis patients with chronic plaque-type disease and to compare this with non-involved psoriatic skin and normal controls.
Methods: Transepidermal water loss (TEWL) readings were taken from involved psoriatic skin and non-involved skin of psoriasis patients as well as the skin of normal controls. Three readings were performed at each site: the basal state, immediately after 20 tape strippings and 1 week post stripping.
Results: Higher baseline, post-stripping and 1-week recovery TEWL readings in psoriatic-involved skin compared to non-involved and normal control skin. No significant difference in barrier recovery rate in psoriatic-involved skin compared to non-involved and normal control.
Conclusion: Although there appears to be a derangement of barrier function in lesional skin of psoriasis patients compared to non-lesional skin and the skin of healthy controls, the barrier recovery function of lesional psoriatic skin is still fully operational.     

Interleukin-6 in the epidermis of patients with psoriasis before and during PUVA treatment

Biopsies from lesional and unaffected skin of 6 patients with psoriasis, taken before and during treatment with psoralen plus UVA (PUVA) were examined immunohistologically, using partially purified polyclonal antibodies to crude supernatants of activated human blood monocytes. By absorption with recombinant derived human monokines, we were able to demonstrate that interleukin-6 (IL-6) (but not IL-1 alpha or IL-1 beta) was located in a laminar and granular pattern in stratum corneum, and on epidermal cell membranes in the viable cellular epidermis. Before PUVA treatment, the intensity and the extension of staining for IL-6 were both markedly increased in lesional skin compared with uninvolved skin. A weaker staining for IL-6 was observed in lesional skin, simultaneous with the clinical improvement of psoriasis. The staining patterns for IL-6 in biopsies from cleared lesional skin and uninvolved psoriatic skin were identical at the conclusion of therapy.     

Patients with psoriasis have elevated levels of serum eosinophil cationic protein and increased numbers of EG2 positive eosinophils in the duodenal stroma

The occurrence of EG2-positive (EG2+) eosinophils and IgE in biopsy specimens of duodenal mucosa and skin from 39 psoriasis patients was studied, with emphasis on the relation to serum eosinophil cationic protein (ECP), serum IgE and the presence or absence of serum IgA and IgG antigliadin antibodies. Psoriasis patients had significantly elevated serum levels of ECP even after exclusion of five of 37 sera which were Phadiatop positive. The elevated serum ECP was not associated with the presence of IgA or IgG antibodies to gliadin. After exclusion of Phadiatop positive sera the serum IgE values did not differ from those of a group of healthy blood donors. Patients with psoriasis had a pronounced increase of EG2+ cells in their duodenal stroma. Patients without antibodies to gliadin tended to have even more EG2+ cells than those with such antibodies and those with increased duodenal intraepithelial lymphocytes. IgE+ cells were present in most duodenal specimens, and in some specimens there were >100 IgE+ cells/section. The number of EG2+ cells was increased in lesional skin and, in some patients, also in non-involved skin, but there was a more pronounced increase in EG2 reactivity in the duodenal than in the skin specimens. IgE reactivity was increased both in non-involved and involved skin and was significantly related to the number of IgE-positive cells in the duodenal stroma. The results of this study indicate that the gastrointestinal tract and the eosinophil granulocyte might be involved in psoriasis in a hitherto unknown way.     

Impaired contact hypersensitivity in untreated psoriasis and the effects of photochemotherapy and dithranol/UV-B

Cell mediated immune reactivity was studied in eighty-five psoriasis patients and twenty-five healthy controls by an improved (quantitative) method for measuring contact hypersensitivity to 2,4 dinitrochlorobenzene (DNCB). Patients were sensitized with 500 μg DNCB, the lowest dose found to sensitize all healthy subjects. Responses to epicutaneous challenge with a series of concentrations of DNCB were measured as volumes calculated from diameter and thickness and the various groups were compared by the differences in the log dose-response curves. Patients with untreated psoriasis were less responsive than healthy controls; responses were less still in patients treated with dithranol/UV-B/tar and they were least of all in patients treated with photochemotherapy with 8-methoxypsoralen and UV-A (PUVA), particularly in those who pigmented least. Sensitization and challenge at different stages of treatment showed that both induction and elicitation of sensitization were impaired by PUVA. The possible relationship of these changes to DNCB metabolism, Langerhans cell damage and a decrease in circulating T cells is discussed. Although the clinical significance of the findings is unknown, treatment with dithranol/UV-B/tar has proved safe over many years of use.