Soluble intercellular adhesion molecule-1 (sICAM-1) in atopic dermatitis

Epicutaneous Sensitization to the Phytocannabinoid β-Caryophyllene Induces Pruritic Inflammation

In recent years, there has been increased accessibility to cannabis for recreational and medicinal use. Incidentally, there has been an increase in reports describing allergic reactions to cannabis including exacerbation of underlying asthma. Recently, multiple protein allergens were discovered in cannabis, yet these fail to explain allergic sensitization in many patients, particularly urticaria and angioedema. Cannabis has a rich chemical profile including cannabinoids and terpenes that possess immunomodulatory potential. We examined whether major cannabinoids of cannabis such as cannabidiol (CBD) and the bicyclic sesquiterpene beta-caryophyllene (β-CP) act as contact sensitizers. The repeated topical application of mice skin with β-CP at 10 mg/mL (50 µL) induced an itch response and dermatitis at 2 weeks in mice, which were sustained for the period of study. Histopathological analysis of skin tissues revealed significant edema and desquamation for β-CP at 10 mg/mL. For CBD and β-CP, we observed a dose-dependent increase in epidermal thickening with profound thickening observed for β-CP at 10 mg/mL. Significant trafficking of CD11b cells was observed in various compartments of the skin in response to treatment with β-CP in a concentration-dependent manner. Mast cell trafficking was restricted to β-CP (10 mg/mL). Mouse proteome profiler cytokine/chemokine array revealed upregulation of complement C5/5a (anaphylatoxin), soluble intracellular adhesion molecule-1 (sICAM-1) and IL-1 receptor antagonist (IL-1RA) in animals dosed with β-CP (10 mg/mL). Moreover, we observed a dose-dependent increase in serum IgE in animals dosed with β-CP. Treatment with β-CP (10 mg/mL) significantly reduced filaggrin expression, an indicator of barrier disruption. In contrast, treatment with CBD at all concentrations failed to evoke scratching and dermatitis in mice and did not result in increased serum IgE. Further, skin tissues were devoid of any remarkable features, although at 10 mg/mL CBD we did observe the accumulation of dermal CD11b cells in skin tissue sections. We also observed increased filaggrin staining in mice repeatedly dosed with CBD (10 mg/mL). Collectively, our studies indicate that repeated exposure to high concentrations of β-CP can induce dermatitis-like pathological outcomes in mice.

T cell co-stimulatory and co-inhibitory pathways in atopic dermatitis

The use of immune checkpoint inhibitors (ICIs) targeting the T cell inhibitory pathways has revolutionized cancer treatment. However, ICIs might induce progressive atopic dermatitis (AD) by affecting T cell reactivation. The critical role of T cells in AD pathogenesis is widely known. T cell co-signaling pathways regulate T cell activation, where co-signaling molecules are essential for determining the magnitude of the T cell response to antigens. Given the increasing use of ICIs in cancer treatment, a timely overview of the role of T cell co-signaling molecules in AD is required. In this review, we emphasize the importance of these molecules involved in AD pathogenesis. We also discuss the potential of targeting T cell co-signaling pathways to treat AD and present the unresolved issues and existing limitations. A better understanding of the T cell co-signaling pathways would aid investigation of the mechanism, prognosis evaluation, and treatment of AD.

Effect of isosecotanapartholide isolated from Artemisia princeps Pampanini on IL‑33 production and STAT‑1 activation in HaCaT keratinocytes

The present study aimed to investigate the anti‑inflammatory effect and mechanism of action of isosecotanapartholide (ISTP), isolated from Artemisia princeps Pampanini extract (APE). The effects of ISTP and APE on the proliferation of human keratinocytes following stimulation by tumor necrosis factor‑α/interferon‑γ were assessed. ISTP and APE downregulated the expression levels of signal transducer and activator of transcription‑1 (STAT‑1), and reduced interleukin‑33 (IL‑33) production. ISTP and APE inhibited the mRNA expression levels of thymus and activation‑regulated chemokine (TARC/CCL17) in a dose‑dependent manner. Western blot analysis demonstrated that ISTP and APE dose‑dependently inhibited protein expression levels of intercellular adhesion molecule‑1 and phosphorylation of STAT‑1. The results of the present study indicate that ISTP may inhibit TARC/CCL17 production in human epidermal keratinocytes via the STAT‑1 signaling pathway and may be associated with the inhibition of IL‑33 production. The current study indicated that ISTP is an active component in APE and may be a potential therapeutic agent for the treatment of inflammatory skin disorders.

Ultraviolet light-emitting-diode irradiation inhibits TNF-α and IFN-γ-induced expression of ICAM-1 and STAT1 phosphorylation in human keratinocytes

BACKGROUND AND OBJECTIVES

Ultraviolet light-emitting diodes (UV-LEDs) are a novel light source for phototherapy. This research investigated the in vitro safety and efficacy of UV-LEDs as a phototherapeutic device for atopic dermatitis (AD).

STUDY DESIGN/MATERIALS AND METHODS

Human keratinocytes and fibroblasts were irradiated by UV-LEDs with a center wavelength of 310 and 340 nm. We examined the effects of UV-LED irradiation on the suppression of TNF-α/IFN-γ-induced activation of STAT1 and ICAM-1 and on NF-κB expression; we used the following methods: cell viability assay, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, Western blotting, and immunocytochemistry.

RESULTS

We observed anti-inflammatory responses through the suppression of TNF-α/IFN-γ-induced expression of TARC and MCP-1/CCL2, IL-1beta, IL-6, and sICAM-1 via blockage of ICAM-1 activation and subsequent activation of STAT1 and NF-κB. The results suggested that UV-LED irradiation inhibited ICAM expression by suppressing TNF-α/IFN-γ-induced NF-κB activation in vitro.

CONCLUSION

We concluded that novel UV-LED (310 and 340 nm) modalities were effective for the treatment of AD and may be promising for the treatment of inflammatory skin diseases.

VCAM-1 blockade delays disease onset, reduces disease severity and inflammatory cells in an atopic dermatitis model

We investigated the functions of critical adhesion molecules ICAM-1 and VCAM-1 in a keratin-14 IL-4-transgenic (Tg) mouse model of atopic dermatitis, the skin lesions of which are characterized by prominent inflammatory cell infiltration, significantly increased mRNAs and proteins of ICAM-1, VCAM-1, E-selectin, P-selectin, L-selectin, and PSGL-1, and significantly increased numbers of dermal vessels expressing these adhesion molecules. We tested the hypotheses that deletion or blockade of these molecules may impede the inflammation by examining the disease progresses in the Tg mice crossed with ICAM-1-knockout mice and Tg mice received anti-VCAM-1-neutralizing antibody. Although the findings of the ICAM-1-knockout Tg mice (Tg/ICAM-1(-/-)) developed skin lesions similar to wide-type ICAM-1 Tg mice (Tg/ICAM-1(+/+)) were surprising, a compensatory mechanism may account for it: the frequency of VCAM-1 ligand, CD49d, on CD3(+) T cells in the lesional skin significantly increased in the Tg/ICAM-1(-/-) mouse, compared with the Tg/ICAM-1(+/+) mice. In contrast, anti-VCAM-1-treated Tg/ICAM-1(-/-) or Tg/ICAM-1(+/+) mice had significantly delayed onset of skin inflammation compared with isotype antibody-treated groups. Moreover, anti-VCAM-1 significantly reduced the skin inflammation severity in Tg/ICAM-1(+/+) mice, accompanied with reduction of mast cell, eosinophil, and CD3(+) T cell infiltration. VCAM-1 is more critical in developing skin inflammation in this model.

Soluble E-selectin and soluble ICAM-1 levels as markers of the activity of atopic dermatitis in children

The expression of adhesion molecules is up-regulated in the skin of atopic dermatitis (AD) patients, and the levels of the soluble adhesion molecules sE-selectin and sICAM-1 have been reported to reflect the endothelial activation in the skin of AD patients. The objective of the study was to investigate the relationship between symptom score and levels of sE-selectin, sICAM-1 and sVCAM-1 before and after 2 weeks of treatment. Eighteen children with an exacerbation of AD were admitted and treated with corticosteroid dilutions under occlusive wet dressings (wet-wrap treatment). Symptom score (objective SCORAD) and levels of sE-selectin, sICAM-1, and sVCAM-1 were assessed before and after 2 weeks of treatment. A significant correlation between the objective SCORAD before treatment and the level of sE-selectin (p < 0.05), but not the level of sICAM-1 (p = 0.7) or sVCAM-1 (p = 0.5) was observed. The treatment resulted in a high degree of remission, which was reflected by a significant decrease in the level of sICAM-1 (p < 0.01), whereas there was only a trend in the level of sE-selectin to decrease (p = 0.08). The level of sE-selectin after 2 weeks of treatment still correlated significantly with the objective SCORAD before treatment (p < 0.005). Soluble E-selectin is a relative objective marker for the severity of AD. SCORAD is a treatment-sensitive symptom of AD, whereas E-selectin may be a more stable underlying systemic representation of AD.

Serum levels of soluble intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and interleukin-2 receptor in patients with vernal keratoconjunctivitis and allergic conjunctivitis

BACKGROUND

Vernal keratoconjunctivitis (VKC) is characterized by severe ocular allergic inflammation that may have a poor visual prognosis. Due to the high frequency of the presence of atopic dermatitis (AD) in VKC, most systemic parameters are dependent on the clinical severity of AD.

METHODS

Serum levels of sICAM-1, sVCAM-1, and sIL-2R were measured by enzyme-linked immunoassay using samples from 30 VKC patients, 30 allergic conjunctivitis (AC) patients, and 20 normal subjects, to determine whether the concentrations of these molecules are elevated.

RESULTS

Circulating sICAM-1 and sIL-2R levels were increased in patients with VKC with AD compared with those in VKC without AD, AC, and normal controls. Serum levels of sVCAM-1 in VKC patients with and without AD were significantly higher than those in controls. No significant difference was found in the levels of sVCAM-1 between patients with VKC with and without AD. In VKC patients with AD, the sIL-2R level correlated significantly with severity of AD, whereas no such correlation was found for sICAM-1 and sVCAM-1.

CONCLUSIONS

These results suggest that serum sVCAM-1 can be used as a marker to differentiate VKC from nonproliferative ocular allergic diseases, and specific immunologic features of VKC may underlie the upregulation of serum sVCAM-1.

Soluble E-selectin, other markers of inflammation and disease severity in children with atopic dermatitis

E-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are membrane-bound adhesion molecules which mediate the attachment of leucocytes to endothelial cells. These molecules are preferentially expressed on activated endothelium. The soluble forms of these molecules (sE-selectin, sP-selectin, sICAM-1 and sVCAM-1) are present in the circulation as a result of shedding. Some of the soluble adhesion molecules have been thought to reflect disease activity in atopic dermatitis (AD). To evaluate their potential to reflect disease activity in AD, we correlated their plasma concentration with clinical severity measured by objective SCORAD (SCORing Atopic Dermatitis). Furthermore, levels of total IgE, specific IgE, and eosinophil cationic protein (ECP) were determined. SCORAD and sE-selectin levels were significantly increased in children with specific IgE for both food and inhalation allergens (P < 0.05). ECP consistently showed an increase with the scores of SCORAD, but no statistical significance was reached. Disease activity was significantly correlated with the plasma levels of sE-selectin (rs = 0.6, P < 0.0005) but not with sP-selectin, sICAM-1 and sVCAM-1. This agrees with recent studies performed in adults with AD, and supports the potential of sE-selection as a parameter for monitoring disease activity in young children with AD.

Evaluation of soluble cell adhesion molecules in atopic dermatitis

Recent studies have indicated the importance of cell adhesion molecules (CAMs) between the vascular endothelium and activated leukocytes in various inflammatory skin diseases. Soluble forms of CAMs (sCAMs) have also been detected in sera from such diseases. In order to elucidate the role of the soluble forms in skin inflammation, we determined the serum levels of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in patients with atopic dermatitis (AD). Using an enzyme-linked immunosorbent assay, we quantified sCAMs levels in 21 patients with atopic dermatitis and in 16 healthy controls. In severe AD patients, levels of these three types of sCAMs were markedly elevated. sE-selectin was significantly elevated in severe AD over the levels in mild AD. A positive correlation with individual clinical activity was found for changes in the sE-selectin and sVCAM-1 levels. sE-selectin levels were correlated with the serum IgE levels and the number of eosinophils. The sVCAM-1 level was also significantly correlated with the number of monocytes. Among these three molecules, sE-selectin appeared to be the most sensitive clinical parameter in monitoring the clinical course of AD patients.

Soluble intercellular adhesion molecule-1 and soluble E-selectin levels in patients with atopic dermatitis

The serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble E-selectin (sE-selectin) were determined by double determinant immunoassay (DDIA), in 37 patients with atopic dermatitis (AD) and 31 age- and sex-matched healthy control subjects. Both sICAM-1 and sE-selectin levels were significantly higher in patients with AD than in healthy controls (P < 0.01), and were correlated with disease severity. A longitudinal study of patients with AD revealed that the levels of sICAM-1 decreased in those in whom symptoms improved. The sICAM-1 levels were significantly correlated with those of sE-selectin. Our studies suggest that such high levels of serum sICAM-1 and sE-selectin may affect the immune response in patients with AD. The levels of sICAM-1 and sE-selectin may be a useful immunological parameter for monitoring disease activity in AD.