Targeting the IFN-γ/CXCL10 pathway in lichen planus

Successful Treatment of Erosive Lichen Planus With Tofacitinib: A Case Series and Review of the Literature

Lichen planus (LP) is an inflammatory disease that affects the skin, hair, nails and mucous membranes. Erosive LP is a chronic and difficult-to-treat subtype of lichen planus, characterized by lesions on mucosal surfaces, particularly in the oral and genital areas. The prevalence of erosive LP has not been determined. To date, treatment has consisted of surgical intervention, photodynamic therapy, laser therapy, and systemic or topical drugs, including steroids and immunomodulatory agents. LP usually need longer periods of treatment and are known as precancerous lesions with a 0.4% to 12% conversion rate. In addition, nearly 25% of patients who develop erosive LP of the vulva are resistant to topical corticosteroids, which are the first choice of treatment. This study reports 6 cases with a mean age of 3.33 years, who were diagnosed with erosive LP lesions and previously failed in treatment with local, intralesional, and systemic steroids, and hydroxychloroquine. These patients were then treated with 10 mg of tofacitinib per day. Interestingly, with the new treatment, the patients' mean overall satisfaction score was 9.16 out of 10 (range: 8-10), the mean pain relief score was 9.16 out of 10 (range: 9-10) and patients' symptom improvement also began an average of 1.33 months after starting treatment (range: 1-2.5 months).

Successful treatment of resistant plantar ulcerative lichen planus with tofacitinib: A case report and comprehensive review of the literature

Key Clinical Message

Ulcerative lichen planus, a challenging variant of lichen planus, has limited response to traditional treatments. Tofacitinib, a JAK-STAT pathway inhibitor, shows promise in effectively treating these lesions.

Abstract

Lichen planus is a mucocutaneous disease that can cause various manifestations, such as itchy erythematous papules, cicatricial alopecia, erosion, and mucocutaneous ulcers. One uncommon manifestation of this disease is the occurrence of erosion and skin ulcers in the soles of the feet, which can cause many problems for patients. Tofacitinib, a Janus Kinase (JAK) inhibitor drug, has found a special place in the field of inflammatory diseases, especially inflammatory skin diseases. In this regard, studies on the effective role of this drug in the treatment of certain forms of lichen planus, including lichen planopilaris, and erosive lichen planus have been performed. In upcoming study, we introduce a 52-year-old woman with lichen planus who complained of ulcerative lesions on the sole of her foot, for whom a diagnosis of plantar ulcerative lichen planus was proposed. After the patient did not respond therapeutically to intralesional triamcinolone acetonide injection, as well as methotrexate and cyclosporine tablets, significant improvement was finally achieved with a 5 mg twice daily dose of tofacitinib. In the following, we will comprehensively review previous articles on the role of tofacitinib in the treatment of lichen planus lesions, as well as the proposed treatment options for erosive and ulcerative lichen planus lesions specifically located on the sole of the foot. Despite limited reports of the successful treatment of mucosal erosive lesions in the oral, esophageal, genital, and ocular mucosa areas with tofacitinib, no previous study has reported the successful treatment of ulcerative lichen planus lesions of the plantar area with tofacitinib. While reporting this case, we recommend considering tofacitinib as a treatment option for plantar ulcerative lichen planus. To confirm its effectiveness, it is necessary to conduct more extensive studies with a larger sample size.

JAK inhibitors in lichen planus: A review of pathogenesis and treatments

Lichen planus (LP) is an auto-inflammatory skin disorder identified by a presence of T-cell lymphocytes at the dermal-epidermal junction. It is hypothesized that the INF-γ/CXCL10 axis fulfills a major role in the onset and persistence of chronic inflammation in LP. Since Janus kinases (JAKs) are involved in the transduction of INF-γ signals, they may be good targets for LP treatment. Several case reports and case series described the safety and efficacy of upadacitinib (2 articles), tofacitinib (6 articles), baricitinib (4 articles), and Ruxolitinib (1 Article) in the treatment of LP variants. The predominant variants that JAK inhibitors improved were lichen planopilaris, nail LP, and erosive LP. Considering the role of the JAK pathway in LP pathogenesis and the evidence provided by these reports, it seems JAK inhibitors would be effective therapeutic agents for LP treatment. Hence, these agents should be trialed and evaluated further.

A proof of concept pilot trial of probiotics in symptomatic oral lichen planus (CABRIO)

OBJECTIVE

To preliminary evaluate the clinical effects of probiotics in individuals with symptomatic oral lichen planus and the possible mechanisms of action.

SUBJECTS AND METHODS

A group of 30 individuals with symptomatic oral lichen planus were recruited in a randomised double-blind parallel group controlled (1:1) proof-of-concept pilot trial of probiotic VSL#3 vs placebo. Efficacy outcomes included changes in pain numeric rating scale, oral disease severity score and the chronic oral mucosal disease questionnaire. Adverse effects, home diary and withdrawals were assessed as feasibility outcomes. Mechanistic outcomes included changes in salivary and serum levels of CXCL10 and IFN-γ and in oral microbial composition.

RESULTS

The probiotic VSL#3 was safe and well tolerated. We observed no statistically significant change in pain, disease activity, quality of life, serum/salivary CXCL10 or oral microbial composition with respect to placebo. Salivary IFN-γ levels demonstrate a trend for a reduced level in the active group (p = 0.082) after 30 days of probiotic consumption.

CONCLUSIONS

The present proof-of-concept study provides some weak not convincing indication of biological and clinical effects of probiotic VSL#3 in individuals with painful oral lichen planus. Further research in this field is needed, with the current study providing useful information to the design of future clinical trials.

The influence of interferon on healthy and diseased skin

Type I interferons (IFNs) are an immunomodulatory class of cytokines that serve to protect against viral and bacterial infection. In addition, mounting evidence suggests IFNs, particularly type I but also IFNγ, are important to the pathogenesis of autoimmune and inflammatory skin diseases, such as cutaneous lupus erythematosus (CLE). Understanding the role of IFNs is relevant to anti-viral responses in the skin, skin biology, and therapeutics for these IFN-related conditions. Type I IFNs (α and β) are produced by recruited inflammatory cells and by the epidermis itself (IFNκ) and have important roles in autoimmune and inflammatory skin disease. Here, we review the current literature utilizing a PubMed database search using terms [interferon/IFN/type I IFN AND lupus/ cutaneous lupus/CLE/dermatomyositis/Sjogrens/psoriasis/lichen planus/morphea/alopecia areata/vitiligo] with a focus on the role of IFNs in basic keratinocyte biology and their implications in the cutaneous autoimmune and inflammatory diseases: cutaneous lupus erythematosus, dermatomyositis, Sjogren's syndrome, psoriasis, lichen planus, alopecia areata and vitiligo. We provide information about genes and proteins induced by IFNs and how downstream mechanisms relate to clinical disease.

Isolated nail lichen planus: An expert consensus on treatment of the classical form

Lichen planus is a benign inflammatory disorder of unknown etiology that may affect the skin, mucosae, scalp, and nails. When the nails are affected, it may lead to permanent destruction with severe functional and psychosocial consequences. Therefore, prompt diagnosis and early treatment are essential, even in mild cases. There are currently no guidelines for the management of nail lichen planus and the published literature on treatment is limited. The aim of this review is to provide practical management recommendations for the classical form of nail lichen planus, especially when restricted to the nails. Topical treatment has poor short-term efficacy and may cause long-term side effects. Instead, intralesional and intramuscular triamcinolone acetonide should be considered first-line therapies. Oral retinoids are second-line choices, and immunosuppressive agents may also be considered.

Significant reduction in the expression of interleukins-17A, 22 and 23A, forkhead box p3 and interferon gamma delineates lichen planus pigmentosus from lichen planus

Recent studies have noticed significant role of interleukin (IL)-17, 22, 23, Foxp3, interferon-gamma (IFN-γ) and Wnt5a in oral and cutaneous lichen planus (LP). This study was undertaken to assess whether similar expression exists in lichen planus pigmentosus (LPP). We recruited 30 patients of treatment-naïve 'LPP' (in absence of cutaneous/mucosal LP elsewhere, group 1), 10 patients having active treatment-naïve cutaneous 'LP' (group 2), 10 patients having 'post-LP' hyperpigmentation (in absence of active LP and off treatment for at least past 3 months, group 3), and 10 controls. Quantitative real-time polymerase chain reaction (qRT-PCR, peripheral blood mononuclear cells [PBMCs] and skin) and immunohistochemistry (IHC, skin) was performed. mRNA expression (in PBMCs) of IL-17A, IL-22, IL-23A, IFN-γ and Foxp3 was significantly decreased in group 1 and 3 as compared to group 2 (p < 0.05). Wnt5a expression was maximal in controls; and while there was no difference between group 1 and 2; whereas expression in group 3 was significantly lesser than group 1 and 2 (p < 0.05). qRT-PCR (skin) and IHC (skin) revealed similar results; and mRNA expression and mean fluorescence intensity of IL-17A, IL-22, IL-23A/R was significantly increased in group 2 and 3 compared to group 1 (p < 0.05). Mean fluorescence intensity and mRNA expression of IFN-γ, Foxp3 and Wnt5a were significantly increased in group 2 compared to group 1 (p < 0.05); whereas the difference between group 1 and 3 was not significant. Mean fluorescence intensity and mRNA expression of IL-17A, 1L-22 and IFN-γ showed no difference between group 2 and 3; whereas that of IL-23A/R, foxp3 and wnt5a were significantly higher in group 2 than group 3 (p < 0.05). Overall, maximal expression of IL-17A, IL-22, IL-23A, IFN-γ and Foxp3 (mRNA PBMCs) was observed in LP. Minimal expression of IL-17A, IL-22, IL-23A/R, IFN-γ and Foxp3 (mRNA skin and IHC skin) was seen in LPP patients. In contrast to LP, LPP lacks the expression of IFN-γ, Foxp3 and the cytokines representing Th17 pathway, and thus seems to have a distinct pathogenesis.

Level-Specific Differences in Systemic Expression of Pro- and Anti-Inflammatory Cytokines and Chemokines after Spinal Cord Injury

While over half of all spinal cord injuries (SCIs) occur in the cervical region, the majority of preclinical studies have focused on models of thoracic injury. However, these two levels are anatomically distinct—with the cervical region possessing a greater vascular supply, grey-white matter ratio and sympathetic outflow relative to the thoracic region. As such, there exists a significant knowledge gap in the secondary pathology at these levels following SCI. In this study, we characterized the systemic plasma markers of inflammation over time (1, 3, 7, 14, 56 days post-SCI) after moderate-severe, clip-compression cervical and thoracic SCI in a rat model. Using high-throughput ELISA panels, we observed a clear level-specific difference in plasma levels of VEGF, leptin, IP10, IL18, GCSF, and fractalkine. Overall, cervical SCI had reduced expression of both pro- and anti-inflammatory proteins relative to thoracic SCI, likely due to sympathetic dysregulation associated with higher level SCIs. However, contrary to the literature, we did not observe level-dependent splenic atrophy with our incomplete SCI model. This is the first study to compare the systemic plasma-level changes following cervical and thoracic SCI using level-matched and time-matched controls. The results of this study provide the first evidence in support of level-targeted intervention and also challenge the phenomenon of high SCI-induced splenic atrophy in incomplete SCI models.

Analysis of anti-tumour necrosis factor-induced skin lesions reveals strong T helper 1 activation with some distinct immunological characteristics

BACKGROUND

Psoriasiform and eczematous eruptions are the most common dermatological adverse reactions linked to anti-tumour necrosis factor (TNF)-α therapy. Yet, a detailed characterization of their immune phenotype is lacking.

OBJECTIVES

To characterize anti-TNF-α-induced inflammatory skin lesions at a histopathological, cellular and molecular level, compared with psoriasis, eczema (atopic dermatitis) and healthy control skin.

METHODS

Histopathological evaluation, gene expression (quantitative real-time polymerase chain reaction) and computer-assisted immunohistological studies (TissueFAXS) were performed on 19 skin biopsies from patients with inflammatory bowel disease (n = 17) and rheumatoid arthritis (n = 2) with new-onset inflammatory skin lesions during anti-TNF-α-therapy.

RESULTS

Although most biopsies showed a psoriasiform and/or spongiotic (eczematous) histopathological architecture, these lesions were inconsistent with either psoriasis or eczema on a molecular level using an established chemokine (C-C motif) ligand 27/inducible nitric oxide synthase classifier. Despite some differences in immune skewing depending on the specific histopathological reaction pattern, all anti-TNF-α-induced lesions showed strong interferon (IFN)-γ activation, at higher levels than in psoriasis or eczema. IFN-γ was most likely produced by CD3/CD4/Tbet-positive T helper 1 lymphocytes.

CONCLUSIONS

New-onset anti-TNF-α-induced eruptions previously classified as psoriasis or spongiotic dermatitis (eczema) exhibit a molecular profile that is different from either of these disorders.

Semaphorin4D Drives CD8+ T-Cell Lesional Trafficking in Oral Lichen Planus via CXCL9/CXCL10 Upregulations in Oral Keratinocytes

Chemokine-mediated CD8⁺ T-cell recruitment is an essential but not well-established event for the persistence of oral lichen planus (OLP). Semaphorin 4D (Sema4D)/CD100 is implicated in immune dysfunction, chemokine modulation, and cell migration, which are critical aspects for OLP progression, but its implication in OLP pathogenesis has not been determined. In this study, we sought to explicate the effect of Sema4D on human oral keratinocytes and its capacity to drive CD8⁺ T-cell lesional trafficking via chemokine modulation. We found that upregulations of sSema4D in OLP tissues and blood were positively correlated with disease severity and activity. In vitro observation revealed that Sema4D induced C-X-C motif chemokine ligand 9/C-X-C motif chemokine ligand 10 production by binding to plexin-B1 via protein kinase B-NF-κB cascade in human oral keratinocytes, which elicited OLP CD8⁺ T-cell migration. We also confirmed using clinical samples that elevated C-X-C motif chemokine ligand 9/C-X-C motif chemokine ligand 10 levels were positively correlated with sSema4D levels in OLP lesions and serum. Notably, we determined matrix metalloproteinase-9 as a new proteolytic enzyme for the cleavage of sSema4D from the T-cell surface, which may contribute to the high levels of sSema4D in OLP lesions and serum. Our findings conclusively revealed an amplification feedback loop involving T cells, chemokines, and Sema4D-dependent signal that promotes OLP progression.

JAK inhibitors in dermatology: The promise of a new drug class

New molecularly targeted therapeutics are changing dermatologic therapy. Janus kinase-signal transducer and activator of transcription (JAK-STAT) is an intracellular signaling pathway upon which many different proinflammatory signaling pathways converge. Numerous inflammatory dermatoses are driven by soluble inflammatory mediators, which rely on JAK-STAT signaling, and inhibition of this pathway using JAK inhibitors might be a useful therapeutic strategy for these diseases. Growing evidence suggests that JAK inhibitors are efficacious in atopic dermatitis, alopecia areata, psoriasis, and vitiligo. Additional evidence suggests that JAK inhibition might be broadly useful in dermatology, with early reports of efficacy in several other conditions. JAK inhibitors can be administered orally or used topically and represent a promising new class of medications. The use of JAK inhibitors in dermatology is reviewed here.