Reduced Efficacy of Biological Drugs in Psoriatic Patients with HLA-A Bw4-80I KIR Ligands

BACKGROUND

Biological drugs (biologics) are a highly effective therapy for the moderate to severe form of psoriasis, an immune-mediated dermatosis with a strong immunogenetic component. The interaction between human leukocyte antigen (HLA) class I ligands and killer immunoglobulin-like receptors (KIR) has a functional significance in the education of natural killer (NK) cells, and can thus influence the response to biologics.

OBJECTIVE

In this study, we investigated the impact of HLA-A and -B KIR ligands in the response to biologics in a cohort of psoriatic patients.

METHODS

Eighty-five patients with moderate to severe psoriasis treated with biologics (adalimumab, etanercept, infliximab, ustekinumab and secukinumab) were enrolled in the study. Clinical response was evaluated as patients attaining 50%, 75% or 90% reduction in the Psoriasis Area and Severity Index (PASI) (PASI 50, 75 or 90, respectively) over 6 months' follow-up. Poor response was defined as PASI 50, and in this case patients shifted to treatment with a different biologic. Fifty-two patients (61.2%) showed excellent response (PASI 90) to the first biologic, while 33 patients (38.8%), needed two or more biologics before reaching an excellent response (PASI 90) and were considered difficult to treat.

RESULTS

Only HLA-A Bw4-80I ligands were associated with the response to biologics; in particular, they were linked with reduced response both at univariable analysis (odds ratio [OR] 3.11, 95% confidence interval [CI] 1.19-8.07; p = 0.019) and multivariable analysis (OR 5.02, 95% CI 1.40-17.97; p = 0.013).

CONCLUSION

We suggest that the HLA-A Bw4-80I epitope could be a marker of reduced responsiveness to biologics. The possible reason for this is an increase of tumour necrosis factor (TNF)-α and the silencing of NK cells through the predominant interaction with the KIR3DL/S pair. HLA-KIR affinities might lead to a more efficient way to prescribe biologics.

Cost effectiveness of ixekizumab versus secukinumab in the treatment of moderate-to-severe plaque psoriasis in Spain

BACKGROUND

Currently, several biologic agents are available for the treatment of moderate-to-severe plaque psoriasis, including newer agents with similar mechanisms of action and efficacy; therefore, there is a need to evaluate their efficiency in terms of cost effectiveness.

OBJECTIVE

This study evaluates the cost effectiveness of recently approved interleukin (IL)-17A antagonists, ixekizumab and secukinumab, for the treatment of moderate-to-severe plaque psoriasis from the perspective of the Spanish National Health System (NHS).

MATERIALS AND METHODS

A Markov model with a lifetime horizon was developed to compare the cost effectiveness of ixekizumab vs. secukinumab in a hypothetical cohort of patients with moderate-to-severe plaque psoriasis. The model used monthly cycles and included four health states: a 12-week induction period, treatment maintenance, best supportive care (BSC), and death. Patients meeting response criteria at the end of the induction period transitioned to maintenance therapy, whereas non-responders transitioned to BSC. It was assumed that, each year, 20% of patients receiving maintenance therapy would discontinue treatment. The model incorporated data from various sources, including published literature, a network meta-analysis, and expert opinion for some variables.

RESULTS

Ixekizumab was dominant over secukinumab in that it gained 0.037 more quality-adjusted life years (QALYs) and saved €1951 in total costs over the lifetime horizon. Probabilistic sensitivity analysis showed a 96.6% likelihood that ixekizumab would be cost effective at a threshold of €30,000 per QALY gained.

CONCLUSION

For the treatment of moderate-to-severe plaque psoriasis in Spain, ixekizumab provided additional QALYs and potential savings for the Spanish NHS compared with secukinumab. Since the magnitude of the differences in costs and QALYs was modest, other factors such as patient preferences (eg, for number of injections) and long-term safety (eg, related to time on the market) may also be important for guiding clinical decisions.

Gold lotion from citrus peel extract ameliorates imiquimod-induced psoriasis-like dermatitis in murine

BACKGROUND

Gold lotion (GL), a natural mixed product made from the peels of six citrus fruits, has recently been identified as possessing anti-oxidative, anti-inflammatory, and immunomodulatory effects. GL has been used to protect skin against UV-induced damage, but its activity against psoriasis, a chronic autoimmune skin disease caused by dysregulation between immune cells and keratinocytes, is not known. We therefore evaluated the effect of GL on imiquimod (IMQ)-induced psoriasis-like inflammation in mice.

RESULTS

GL treatment significantly attenuated IMQ-induced psoriasis-like symptoms in mice. The inflammatory cytokines upregulated by IMQ in skin lesions were also inhibited by feeding GL. In addition, GL treatment reduced the infiltration of CD4⁺ T cells/neutrophils in skin lesions and the percentage of IL-17-/IL-22-producing T cells in lymph nodes. Furthermore, GL impaired IMQ-induced type I interferon production by plasmacytoid dendritic cells (pDCs) in vitro.

CONCLUSION

Our results indicate GL can act to suppress the initiation of psoriasis and strongly suggest that GL may have potential to be applied to the treatment of psoriasis. © 2018 Society of Chemical Industry.

MicroRNA let-7b inhibits keratinocyte differentiation by targeting IL-6 mediated ERK signaling in psoriasis

Background

The extensive involvement of microRNA (miRNA) in the pathophysiology of psoriasis is well documented. However, in order for this information to be useful in therapeutic manipulation of miRNA levels, it is essential that detailed functional mechanisms are elucidated. This study aimed to explore the effects of IL-6 targeting by let-7b and ERK1/2 mediated signaling on keratinocyte differentiation in psoriasis.

Methods

Following imiquimod cream (IMQ) application to let-7b^TG (keratinocyte-specific let-7b overexpression mouse) and control mice for 7 days, we analyzed erythema, scaling and thickening of skin. A dual luciferase reporter assay and bioinformatics was carried out to detect target gene of let-7b. Additionally, the differentiation markers were measured. Immunohistochemistry analyses demonstrate a relationship of let-7b with IL-6 and ERK signaling.

Results

we found let-7b^TG inhibits acanthosis and reduces the disease severity by treatment with IMQ compared to wild-type mice. Further study illustrated that let-7b promotes differentiation of keratinocytes in vivo and in vitro. Using bioinformatics and reporter gene assays, we found that IL-6 is a target gene of let-7b. In psoriasis, high expression levels of IL-6 lead to increased acivation of p-ERK1/2. High levels of let-7b^TG transgene expression suppresses IL-6 expression and leads to increased keratinocyte differentiation. Moreover, let-7b acts as an upstream negative regulator of the ERK signaling pathway in keratinocytes of psoriasis.

Conclusions

Our result reveals a previously unknown mechanism for regulation of IL-6 levels during psoriasis by let-7b and highlights a critical role for the ERK1/2 signaling pathway in epidermal differentiation during psoriasis.

Trial registration

The ethical approval for this study was from the Affiliated Hospital of Medical University of Anhui _ Fast_ PJ2017–11–14.

Electronic supplementary material

The online version of this article (10.1186/s12964-018-0271-9) contains supplementary material, which is available to authorized users.

Rapamycin ameliorates psoriasis by regulating the expression and methylation levels of tropomyosin via ERK1/2 and mTOR pathways in vitro and in vivo

Psoriasis is a chronic inflammatory disease, affecting more than millions of people in the world. Recently, the mTOR inhibitor rapamycin (RAPA) was reported to be involved in the pathogenesis of psoriasis. However, the underlying mechanism remains unclear. Haematoxylin and eosin staining was used to examine the effects of RAPA on inflammatory level of lesional tissues from patients with psoriasis and animal models. Quantitative real-time PCR, immunohistochemistry and western blot assay were performed to assess the effects of RAPA on tropomyosins (TPMs) expression in patients with psoriasis, cell models and animal models. Phalloidin staining was used to assess the RAPA effects on cell skeleton. The effects of RAPA on cell proliferation and cell cycle were detected by CCK-8 assay, EdU staining and flow cytometry. Methylation status of TPMs was analysed by methylation-specific PCR. The expression of TPM1 and TPM2 was significantly downregulated, while their methylation level was obviously higher in the lesional tissues, cell models and animal models of psoriasis. After treated with RAPA, the expression and methylation levels of TPMs were all restored in the cell models and animal models of psoriasis. RAPA inhibited cell proliferation and decreased the ratio of S phase cell in Hacat or human epidermal keratinocytes cell models of psoriasis. Finally, the activated ERK1/2 and mTOR pathways in the cell model and animal model of psoriasis were suppressed by the treatment of RAPA. RAPA could be used as an effective agent for the treatment of psoriasis by decreasing the methylation level of TPM1 and TPM2 via inhibiting the ERK1/2 and mTOR signalling pathways.