Effect of calcipotriol on epidermal cell populations in alefacept-treated psoriatic lesions

BACKGROUND AND OBJECTIVES

The effect of the established antipsoriatic treatment with topical calcipotriol (with a maximum of 100 g per week) in addition to systemic treatment with alefacept, a new biological agent for psoriasis, on epidermal cell populations in the psoriatic lesion was investigated using a combination of the Zenon labelling technique and microscopic image analysis. Epidermal cell populations were measured quantitatively with this sensitive method.

PATIENTS/METHODS

Frozen sections of non-treated psoriatic epidermis and psoriatic epidermis treated with either alefacept intramuscular or alefacept intramuscular in combination with topical calcipotriol for 12 weeks were compared immunohistochemically. Antibodies against keratin 6, 10 and 15 were labelled with the Zenon technique, whereas antibodies against the Ki-67 antigen and beta-1 integrin were covalently Fluorescein Isothiocyanate (FITC)-labelled. Using image analysis, these markers were measured in the epidermis in a standardized manner.

RESULTS AND CONCLUSIONS

Treatment of psoriasis with alefacept resulted in a good clinical response in several patients and in a normalization of epidermal expression of the immunohistochemical parameters for differentiation and proliferation. The addition of topical calcipotriol resulted in a faster clinical improvement with a similar overall clinical response and a similar response of epidermal cell populations as compared to treatment with alefacept monotherapy after 12 weeks of treatment. This study also suggests that the appearance of keratin 15 has a predictive value for the duration of remission. It can be concluded that the addition of a low-dose calcipotriol treatment does not contribute to the clinical efficacy of alefacept, both at the clinical level and with respect to markers for epidermal proliferation and differentiation.

Plaque psoriasis vs. atopic dermatitis and lichen planus: a comparison for lesional T-cell subsets, epidermal proliferation and differentiation

BACKGROUND

T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in plaque psoriasis and other inflammatory dermatoses have only sparsely been performed.

OBJECTIVES

To compare plaque psoriasis vs. atopic dermatitis and lichen ruber planus with respect to T-cell subsets, epidermal proliferation and keratinization.

PATIENTS AND METHODS

Biopsies were taken from untreated lesional skin of patients, six with psoriasis, six with atopic dermatitis and six with lichen planus. T-cell subsets (CD4+, CD8+, CD45RO+, CD45RA+, CD2+, CD25+), an epidermal proliferation (Ki-67) and a keratinization marker (K10) were stained immunohistochemically and quantified using image analysis.

RESULTS

The high number of CD8+ T cells (52 +/- 13 cells mm(-1)) found in the psoriatic epidermis was not found in the epidermis of atopic dermatitis (9 +/- 4), nor in the epidermis of lichen planus (34 +/- 10). The other T-cell subsets in the epidermis and dermis showed no statistically significant differences between psoriasis and atopic dermatitis. In contrast to the limited presence of CD4+, CD8+ and CD2+ in the psoriatic dermis (110 +/- 19, 27 +/- 9, 127 +/- 41, cells mm(-1), respectively), more impressive numbers of these cells were observed in the dermis of lichen planus (300 +/- 53, 144 +/- 38, 272 +/- 48, respectively). CD45RO+ memory effector T-cell counts were significantly higher in the epidermis of lichen planus (39 +/- 10) than in psoriasis (19 +/- 5). Psoriatic epidermis proved to have major keratinocyte hyperproliferation (247 +/- 26 cells mm(-1) lamina basalis), as compared with atopic dermatitis (134 +/- 15) and lichen planus (128 +/- 20). Furthermore, a marked decreased expression of keratin 10 was observed in psoriasis (41% of epidermal area) contrary to atopic dermatitis (70%).

CONCLUSIONS

Psoriatic epidermis exhibits a pronounced CD8+ epidermotropism with accompanying epidermal hyperproliferation and abnormal keratinization, which changes are only minimally expressed in atopic dermatitis and lichen planus. In plaque psoriasis, substantially fewer activated CD4+ and CD8+ T cells in the dermis and less CD45RO+ T cells in the epidermis are present in comparison with lichen ruber planus.

Flexural versus plaque lesions in psoriasis: an immunohistochemical differentiation

Clinical presentation, therapeutic options, micro-environment and HLA-typing have been reported to be different in flexural psoriasis as compared to plaque psoriasis. We were interested in any difference concerning the pathogenesis of both conditions. By analysing T-cell subsets, NK-T cells and proliferation and differentiation markers, insight into the pathogenesis of both subtypes was obtained. Quantitative studies of T-cell subsets, cells expressing NK-receptors and markers of proliferation and differentiation in flexural and plaque psoriasis were investigated. Biopsies from 6 patients with both flexural and plaque lesions were obtained and processed for immunohistochemistry. Several T-cell subsets were stained: CD4+, CD8+, CD2+, CD25+, CD45RO+ and CD45RA+ T-cells. In addition cells expressing NK receptors were stained: CD94+ cells and CD161+ cells. T-cell subsets and cells expressing NK-receptors were analysed by immunohistochemical scoring. The proliferation marker Ki-67 and differentiation marker keratin-10 were revealed immunohistochemically by MIB-1 and RKSE60 respectively. Both markers were analysed using quantitative image analyses. The number of Ki-67 positive nuclei and the percentage of keratin-10 positive epidermal cells in flexural and plaque psoriasis were comparable. There is no difference between flexural and plaque psoriasis concerning other T-cell subsets. However a highly significant reduction is seen in flexural psoriasis with respect to CD161+ cells in the dermis. The similarity of chronic plaque psoriasis compared to flexural psoriasis with respect to T-cell subsets, epidermal proliferation and keratinization suggests that both conditions are pathogenetically identical. We propose the decreased quantity of lesional CD161+ cells in the dermis of flexural psoriatic lesions may result from chronic microbial challenge in flexural psoriasis.

Safety and efficacy of combined high-dose treatment with calcipotriol ointment and solution in patients with psoriasis

BACKGROUND

In the vast majority of psoriatic patients, psoriatic lesions are localised on the body as well as on the scalp. Therefore, safety data on the combined use of calcipotriol in lotion and calcipotriol in ointment are needed.

OBJECTIVE

This study investigated the effect of high-dose treatment with a combination of calcipotriol ointment and scalp solution on calcium metabolism, indices of bone turnover and PASI in patients with extensive psoriasis.

METHODS

Following a 2-week wash-out period, 88 patients were randomised to 4 weeks of treatment with either calcipotriol ointment/scalp solution (80-100 g/week and 30-50 ml/week, respectively; n = 41) or with a dithranol/tar regimen (n = 47). Patients were seen at weeks 1, 2 and 4 during treatment and 1 week following cessation of treatment.

RESULTS

No significant differences at the end of treatment were found between the 2 groups with respect to 24-hour urinary excretion of calcium (expressed as calcium/creatinine ratio), phosphate or pyridinoline, serum concentrations of calcium (albumin corrected), creatinine, phosphate, parathyroid hormone, 25-hydroxyvitamin D(3), 1,25-dihydroxyvitamin D(3), osteocalcin, alkaline phosphatase (total and bone-specific iso-enzymes) or 1-collagen telopeptide. At the end of treatment, the psoriasis area and severity index had decreased by 57.4% in the calcipotriol group and by 36.1% in the dithranol/tar group (p = 0.004). Investigators' and patients' assessments of overall efficacy also favoured treatment with calcipotriol (p < 0.001).

CONCLUSION

The combined use of calcipotriol ointment/scalp solution did not affect the indices of calcium metabolism or bone turnover and was significantly more effective than dithranol/tar in reducing disease severity and extent in patients with extensive psoriasis.

Efficacy and safety of a new combination of calcipotriol and betamethasone dipropionate (once or twice daily) compared to calcipotriol (twice daily) in the treatment of psoriasis vulgaris: a randomized, double-blind, vehicle-controlled clinical trial

BACKGROUND

Calcipotriol and betamethasone dipropionate are both widely used, effective treatments for psoriasis. Vitamin D analogues and topical corticosteroids have different mechanisms of action in the treatment of psoriasis. A new vehicle has been developed in order to contain both calcipotriol (50 micro g g-1) and betamethasone dipropionate (0.5 mg g-1) in an ointment form. By using calcipotriol and a corticosteroid together, greater efficacy may be achieved than by using either compound alone.

OBJECTIVES

The present study was conducted in order to compare the clinical efficacy and safety of the combined ointment formulation used once daily with the vehicle ointment used twice daily, calcipotriol ointment used twice daily and the combined formulation used twice daily in psoriasis vulgaris.

METHODS

This was an international, multicentre, prospective, randomized, double-blind, vehicle-controlled, parallel group, 4-week study in patients with psoriasis vulgaris amenable to topical treatment. Patients were randomized to one of four treatment groups: combined formulation once daily, combined formulation twice daily, calcipotriol twice daily or vehicle twice daily. Efficacy and safety were assessed.

RESULTS

There was no statistically significant difference in the mean percentage change in the Psoriasis Area and Severity Index (PASI) from baseline to end of treatment between the two combined formulation groups, but the difference in PASI reduction was significantly higher in the combined formulation groups (68.6% once daily, 73.8% twice daily) than in both the twice daily calcipotriol group (58.8%) and the vehicle group (26.6%). Safety data showed the frequency of adverse events to be less in the combined formulation groups than in both the calcipotriol group and the vehicle group. The proportion of patients with lesional/perilesional adverse reactions was less in the combined formulation groups and vehicle group than in the calcipotriol group (9.9% combined formulation once daily, 10.6% combined formulation twice daily, 19.8% calcipotriol, 12.5% vehicle).

CONCLUSIONS

No statistically significant nor clinically relevant difference in efficacy was seen between the combined formulation used once daily and twice daily. When compared to vehicle ointment or calcipotriol ointment alone, the combined formulation was shown to be clearly more efficacious.