A Targetable, Noncanonical Signal Transducer and Activator of Transcription 3 Activation Induced by the Y-Less Region of IL-22 Receptor Orchestrates Imiquimod-Induced Psoriasis-Like Dermatitis in Mice

3D Histological Analysis of Soft Tissues by Contrast-Enhanced X-Ray Microfocus Computed Tomography: Screening and Staining Optimization of Contrast-Enhancing Staining Agents

The gold standard for studying biological soft tissues at the microscale (i.e., histology) is tissue sectioning with subsequent colorimetric or fluorescent staining and visual inspection under the microscope. When tissue integrity must be maintained for 3D histological assessment, contrast-enhanced microfocus X-ray computed tomography (CECT) is a promising solution, but there is still a lack of staining protocol optimization of contrast-enhancing staining agents (CESAs). Therefore, in this study, mouse auricles were incubated with Hafnium-substituted Wells-Dawson polyoxometalate, cationic iodinated contrast agent, or Lugol's iodine and were imaged with high-resolution CECT. Alignment with corresponding H&E-stained sections enabled the identification and segmentation of different tissue types. Contrast differences between tissue types were increased by washing the samples after staining or by combining CESAs. Finally, we proved that the latter could be used to quantitatively assess the 3D thickness distribution of the epidermis in the ears of a mouse model of psoriasis-like dermatitis. In conclusion, CECT and bright-field microscopy are complementary and not mutually exclusive techniques for the histological assessment of biological tissues. While bright-field microscopy gives detailed information about the cellular composition of tissues, CECT provides a better insight into the spatial interrelationship of tissues and is a powerful tool for performing 3D structural quantification.

Bibliometric analysis and description of research trends on T cells in psoriasis over the past two decades (2003-2022)

Background

It is now understood that T cells play a key role in the occurrence and development of psoriasis. Herein, a bibliometric analysis was conducted to summarize the content and trends of T cell-related research in psoriasis.

Methods

A bibliometric analysis was conducted on publications pertaining to T cells in psoriasis between 2003 and 2022 retrieved from the Web of Science Core Collection (WoSCC) database using tools such as CiteSpace, the Bibliometrix R package, and VOSviewer.

Results

The study included a total of 3595 articles authored by 14,188 individuals, including all coauthors in article bylines. The Laboratory for Investigative Dermatology at Rockefeller University, led by James G Krueger, has made significant contributions to this field through focusing on the pathogenesis of psoriasis and exploring the potential of using biological agents to treat psoriasis. Furthermore, targeted inhibitors have significantly impacted the treatment of psoriasis, with researchers focusing on small-molecule targeted drugs as a new area of research that could potentially replace biological agents.

Conclusions

Research has established the efficacy and long-term safety of targeted inhibition of T cell-related targets. Deucravacitinib, a psoriasis treatment drug targeting TYK2 as an allosteric inhibitor, has attracted significant attention and raised high expectations.

Psoriasis and Leprosy: An Arcane Relationship

Purpose

Psoriasis (Ps) and leprosy are chronic inflammatory skin disorders, characterised by enhanced innate and adaptive immunity. Ps and leprosy rarely coexist. The molecular immune mechanism of the Ps and leprosy rarely coexistence is unclear.

Patients and Methods

RNA-sequencing (RNA-seq) was performed on 20 patients with Ps, 5 adults with lepromatous leprosy (L-lep), and 5 patients with tuberculoid leprosy (T-lep) to analyse the differentially expressed genes (DEGs) between them. Moreover, the biological mechanism of Ps and leprosy was explored by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Gene Ontology (GO) analysis, Gene Set Enrichment Analysis analysis, and protein-protein interaction (PPI) analyses. Finally, 13 DEGs of 10 skin biopsies of Ps patients, 6 samples of L-lep patients, 6 samples of T-lep patients and 5 healthy controls were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR).

Results

The PPI network was constructed and primarily associated with immune response, IL-17 signalling, and Toll-like receptor pathway between Ps and leprosy. Th17 markers (interleukin (IL)-19, IL-20, IL-36A, IL-36G, IL-22, IL-17A, and lipocalin-2 (LCN2) had higher expression in Ps than in L-lep and T-lep, whereas macrophage biomarkers (CLEC4E and TREM2), SPP1, and dendritic cell (DC)-related hallmarks (ITGAX) and TNF-a had significantly lower expression across Ps and T-lep than in L-lep.

Conclusion

To put it simply, Ps patients with IL-17A, IL-19, IL-20, IL-36A, IL-36G, and IL-22 in conjunction with LCN2 with up-graduated expression might be not susceptible to L-lep. However, high levels of CLEC4E, TREM2, and SPP1 in L-lep patients indicated that they unlikely suffered from Ps.

Inhibition of JAK1/STAT3 pathway by 2-methoxyestradiol ameliorates psoriatic features in vitro and in an imiquimod-induced psoriasis-like mouse model

Psoriasis is characterized by hyperproliferative keratinocytes, dilated capillaries and leukocyte infiltration. 2-Methoxyestradiol (2-ME) has shown significant inhibition on proliferation, angiogenesis and inflammation. To evaluate the anti-psoriatic potential of 2-ME, psoriasis-like dermatitis was induced by topical application of imiquimod (IMQ) on the dorsal skin of C57BL/6 mice for seven consecutive days, followed by treatment of vehicle or 2-ME ointment from Day 4 on. The psoriasis area and severity index (PASI) was assessed daily. On Day 8, skin histology and spleen index were assessed. The effects of 2-ME on the proliferation, apoptosis, cell cycle, vascular endothelial growth factor A (VEGFA), and Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathways of HaCaT cells stimulated by interleukin-17 (IL-17A) were detected, together with its effect on the proliferation, tube formation and VEGF receptor expression of human umbilical vein endothelial cells (HUVECs). We found that topical 2-ME treatment significantly improved IMQ-induced psoriasis-like dermatitis and decreased the PASI scores, the activation of STAT3 in the skin (P < 0.05), and the spleen index in mice (P < 0.01). In vitro, 2-ME inhibited the proliferation of HaCaT cells by inducing apoptosis and G2/M phase arrest (P < 0.01). Moreover, 2-ME suppressed IL-17A-induced VEGFA (2.5 μM: P < 0.05; 5 μM: P < 0.01) and phosphorylation of STAT3 by blocking p-JAK1 in HaCaT cells and prevented tube formation (P < 0.01) and proliferation by targeting VEGF receptors 1 (VEGFR1) and 2 (VEGFR2) in HUVECs. We conclude that 2-ME alleviated psoriasis in vivo and in vitro by inhibiting JAK1/STAT3 pathway and was a promising therapeutic agent for psoriasis.

Blocking GARP-mediated activation of TGF-β1 did not alter innate or adaptive immune responses to bacterial infection or protein immunization in mice

Abstract

Transmembrane protein GARP binds latent TGF-β1 to form GARP:(latent)TGF-β1 complexes on the surface of several cell types including Tregs, B-cells, and platelets. Upon stimulation, these cells release active TGF-β1. Blocking TGF-β1 activation by Tregs with anti-GARP:TGF-β1 mAbs overcomes resistance to PD1/PD-L1 blockade and induces immune-mediated regressions of murine tumors, indicating that Treg-derived TGF-β1 inhibits anti-tumor immunity. TGF-β1 exerts a vast array of effects on immune responses. For example, it favors differentiation of T_H17 cells and B-cell switch to IgA production, two important processes for mucosal immunity. Here, we sought to determine whether treatment with anti-GARP:TGF-β1 mAbs would perturb immune responses to intestinal bacterial infection. We observed no aggravation of intestinal disease, no systemic dissemination, and no alteration of innate or adaptative immune responses upon oral gavage of C. rodentium in highly susceptible Il22r^−/− mice treated with anti-GARP:TGF-β1 mAbs. To examine the effects of GARP:TGF-β1 blockade on Ig production, we compared B cell- and T_H cell- responses to OVA or CTB protein immunization in mice carrying deletions of Garp in Tregs, B cells, or platelets. No alteration of adaptive immune responses to protein immunization was observed in the absence of GARP on any of these cells. Altogether, we show that antibody-mediated blockade of GARP:TGF-β1 or genetic deletion of Garp in Tregs, B cells or platelets, do not alter innate or adaptive immune responses to intestinal bacterial infection or protein immunization in mice. Anti-GARP:TGF-β1 mAbs, currently tested for cancer immunotherapy, may thus restore anti-tumor immunity without severely impairing other immune defenses.

Précis

Immunotherapy with GARP:TGF-β1 mAbs may restore anti-tumor immunity without impairing immune or inflammatory responses required to maintain homeostasis or host defense against infection, notably at mucosal barriers.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00262-021-03119-8.

The Role of T Helper 22 Cells in Dermatological Disorders

T helper 22 (Th22) cells are a newly identified subset of CD4+ T cells that secrete the effector cytokine interleukin 22 (IL-22) upon specific antigen stimulation, barely with IFN-γ or IL-17. Increasing studies have demonstrated that Th22 cells and IL-22 play essential roles in skin barrier defense and skin disease pathogenesis since the IL-22 receptor is widely expressed in the skin, especially in keratinocytes. Herein, we reviewed the characterization, differentiation, and biological activities of Th22 cells and elucidated their roles in skin health and disease. We mainly focused on the intricate crosstalk between Th22 cells and keratinocytes and provided potential therapeutic strategies targeting the Th22/IL-22 signaling pathway.

JAK/STAT: Why choose a classical or an alternative pathway when you can have both?

A subset of cytokines triggers the JAK‐STAT pathway to exert various functions such as the induction of inflammation and immune responses. The receptors for these cytokines are dimers/trimers of transmembrane proteins devoid of intracellular kinase activity. Instead, they rely on Janus kinases (JAKs) for signal transduction. Classical JAK‐STAT signalling involves phosphorylation of cytokine receptors' intracellular tyrosines, which subsequently serve as docking sites for the recruitment and activation of STATs. However, there is evidence to show that several cytokine receptors also use a noncanonical, receptor tyrosine‐independent path to induce activation of STAT proteins. We identified two main alternative modes of STAT activation. The first involves an association between a tyrosine‐free region of the cytokine receptor and STATs, while the second seems to depend on a direct interaction between JAK and STAT proteins. We were able to identify the use of noncanonical mechanisms by almost a dozen cytokine receptors, suggesting they have some importance. These alternative pathways and the receptors that employ them are discussed in this review.

Treating Psoriasis with a Light Touch

Although several anticytokine antibodies and inhibitors are available for the treatment of psoriasis, more effective or better-tolerated alternatives would be of interest. In their article in the Journal of Investigative Dermatology, Michiels et al. (2021) propose a new strategy that targets an alternative activation pathway of the IL-22 receptor to attenuate murine psoriasis-like skin inflammation without affecting IL-22‒dependent barrier defense in the gut.