Alterations in ICAM-1 and ELAM-1 expression in psoriatic lesions following various treatments

Evaluation of ICAM-1 expression and vascular changes in the skin of patients with plaque, pustular, and erythrodermic psoriasis

BACKGROUND

Psoriasis is a chronic inflammatory disease. Pustular, erythrodermic, and extensive plaque psoriasis are responsible for systemic complications. Systemic capillary leak syndrome is the complication with greater progression to death and occurs due to vascular changes.

PURPOSE

The aim of this study was to evaluate vascular changes through the expression of CD34 and ICAM-1 in plaque, pustular, and erythrodermic psoriasis.

METHODS

The sample consisted of seven patients with erythrodermic psoriasis, 24 with moderate-severe plaque psoriasis, 14 with mild plaque psoriasis and 13 with pustular psoriasis. Patients were submitted to physical examination and skin biopsy for histopathological examination and immunohistochemical analysis with anti-CD34 and anti-ICAM-1 antibodies. Subsequently, tissue fragments were organized by groups using the Tissue Macroarray (TMA) technique to perform immunohistochemistry.

RESULTS

In 58 patients, analysis of vessels using anti-CD34 demonstrated vascular immunostaining in superficial dermis and between dermal papillae. There were more blood vessels in erythrodermic psoriasis, followed by plaque psoriasis. In erythrodermic psoriasis, there were small and few tortuous blood vessels with great dilatation, while plaque psoriasis presented larger vessels that were less dilated and more tortuous. There was an intense and localized expression of ICAM-1 in endothelial and lymphocytic cells in all groups, with significant differences.

CONCLUSIONS

Vascular alterations are important in psoriasis, with an increase in the number of blood vessels and ICAM-1 overexpression, especially in erythrodermic form. Therefore, vascular changes and the expression of intercellular adhesion molecules could help to diagnose the erythrodermic form of psoriasis.

Ultrastructural Findings and Tumor Necrosis Factor-alpha and Intercellular Adhesion Molecule-1 Expression in Psoriasis Patients Before and After Oral Cyclosporin A Therapy

Elevated levels of proinflammatory cytokines, including tumor necrosis factor-alpha, are found in skin lesions and plasma of patients with psoriasis. Clinical improvement of psoriasis with cyclosporin A treatment is accompanied by downmodulation of proinflammatory epidermal cytokines. In this study to determine the effects of cyclosporin A on the ultrastructural changes and tumor necrosis factor-alpha and intercellular adhesion molecule-1 expression in psoriasis, biopsy specimens before and after cyclosporin A treatment were evaluated ultrastructurally and immunohistochemically. Ten patients were given 3-7.5 mg/kg oral cyclosporin A for 6 months. Before and after treatment full thickness of 4-mm punch biopsies were obtained from patients and from 6 healthy volunteers. Samples were processed for electron microscopic and immunohistochemical evaluation. The treatment was well tolerated with complete clinical improvement. The ultrastructural changes such as reduction of tonofilaments, dilatation of intercellular space, and interruption in lamina densa were recovered by cyclosporin A treatment. The increased staining intensity of tumor necrosis factor-alpha and intercellular adhesion molecule-1 on epidermal keratinocytes and endothelial cells was reduced after cyclosporin A therapy. Cyclosporin A treatment results in total normalization of the electron microscopic picture of psoriasis and its beneficial effect depends on the direct inhibition of tumor necrosis factor-alpha and consequently intercellular adhesion molecule-1.

Therapeutic potential of selectin antagonists in psoriasis

Psoriasis is a systemic chronic inflammatory disorder. One of the major characteristics is an excess of infiltration of inflammatory cells, mainly lymphocytes, into the skin. Because the adhesion family of selectins is suggested to play a relevant role in this process, selectins have emerged as an interesting target for drug discovery and development in psoriasis. Different strategies targeting selectins have been described. This review discusses these approaches and summarises the current development of selectin antagonists for the treatment of psoriasis. An expert opinion will give the authors' personal opinion about selectin antagonism in psoriasis and which approach might be preferable.

Methotrexate inhibits proliferation and regulation of the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 by cultured human umbilical vein endothelial cells

BACKGROUND

The mechanism by which a low dose of methotrexate (MTX) works to treat psoriasis is not clear. The overexpression of cell adhesion molecules on dermal vessels is important in the pathogenesis of psoriasis and is probably induced by upregulation of tumour necrosis factor (TNF)-alpha.

OBJECTIVES

To determine the effects of MTX at concentrations comparable with in vivo levels after the administration of low-dose MTX to human umbilical vein endothelial cells (HUVEC) on the growth and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1).

METHODS

Cell proliferation assay, immunostaining, immunoblotting, cell enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction (RT-PCR) were performed to examine the effects of MTX on HUVEC.

RESULTS

MTX inhibited the proliferation of HUVEC at 10-7 mol L-1 and 10-6 mol L-1 without showing cytotoxic effects. It also inhibited TNF-alpha-induced ICAM-1 and VCAM-1 expression by HUVEC at 10-6 mol L-1. The inhibitory effect of MTX was more pronounced on ICAM-1 expression than on VCAM-1 expression. RT-PCR analysis revealed that TNF-alpha-induced ICAM-1 gene expression was strongly downregulated by MTX.

CONCLUSIONS

Low-dose MTX may act on psoriasis by suppressing the TNF-alpha-induced expression of ICAM-1 and VCAM-1 by vascular endothelial cells. Inhibition of neovascularization may be another mechanism of action of MTX.

PUVA therapy: current concerns in Japan

Photochemotherapy using methoxsalen in combination with long-wave ultraviolet light (PUVA) is an essential modality in the treatment of various skin diseases. Major therapeutic regimens include oral, topical and water-delivery methods. An adequate regimen should be chosen regarding cases of disease, extent of involvement and the age of patients. In Japan, however, treatment techniques and protocols have not yet been standardized. PUVA therapy may be a first choice in the early stages of mycosis fungoides and a second choice or an adjunctive measure in other diseases, such as psoriasis, vitiligo and atopic dermatitis, which have been disabling or resistant to conventional treatments. Japanese guidelines for PUVA therapy of psoriasis are being prepared to be produced. Risks and benefits must be weighed and the patient orientation is necessary to complete the treatment and also to minimize side-effects. Although possible risks for skin cancers in Japanese patients have been reported to be much lower, a careful monitoring of the patient's skin changes is recommended. While action mechanisms are not completely understood, recent investigations suggest that both antiproliferative and immunomodulatory effects are involved. This review article deals with the recent progress in clinical and basic research on PUVA therapy, focusing on our current concerns.

Dimethylfumarate is an inhibitor of cytokine-induced E-selectin, VCAM-1, and ICAM-1 expression in human endothelial cells

Most studies on the antipsoriatic mode of action of dimethylfumarate focused on its antiproliferative effects in keratinocytes. Because inflammatory skin diseases are associated with an upregulation of endothelial cell adhesion molecules and because the presence of inflammatory cells in dermis and epidermis is considered an important feature in psoriasis, we tested the effect of DMF on cytokine-induced adhesion molecule expression in HUVEC, using in situ ELISA and Northern blotting. Dimethylfumarate inhibited ICAM-1, VCAM-1, and E-selectin expression and reduced adhesion of U937 cells to stimulated HUVEC. Monoethylfumarate and fumaric acid had no effect. Similar inhibitory effects for DMF on VCAM-1 expression were observed after stimulation of HUVEC with LPS, PMA, IL-4, and IL-1 alpha or in combinations with TNF alpha. These data are in agreement with previously reported effects of DMF on intracellular thiol levels and inhibition of NF-kappa B activation. The inhibitory effect on cytokine-induced endothelial adhesion molecule expression may represent another target of dimethylfumarate in psoriasis.