High levels of LIGHT and low levels of soluble herpesvirus entry mediator in sera of patients with atopic dermatitis

LIGHT signaling through LTβR and HVEM in keratinocytes promotes psoriasis and atopic dermatitis-like skin inflammation

Psoriasis (PS) and atopic dermatitis (AD) are common skin inflammatory diseases characterized by hyper-responsive keratinocytes. Although, some cytokines have been suggested to be specific for each disease, other cytokines might be central to both diseases. Here, we show that Tumor necrosis factor superfamily member 14 (TNFSF14), known as LIGHT, is required for experimental PS, similar to its requirement in experimental AD. Mice devoid of LIGHT, or deletion of either of its receptors, lymphotoxin β receptor (LTβR) and herpesvirus entry mediator (HVEM), in keratinocytes, were protected from developing imiquimod-induced psoriatic features, including epidermal thickening and hyperplasia, and expression of PS-related genes. Correspondingly, in single cell RNA-seq analysis of PS patient biopsies, LTβR transcripts were found strongly expressed with HVEM in keratinocytes, and LIGHT was upregulated in T cells. Similar transcript expression profiles were also seen in AD biopsies, and LTβR deletion in keratinocytes also protected mice from allergen-induced AD features. Moreover, in vitro, LIGHT upregulated a broad spectrum of genes in human keratinocytes that are clinical features of both PS and AD skin lesions. Our data suggest that agents blocking LIGHT activity might be useful for therapeutic intervention in PS as well as in AD.

The BTLA-HVEM complex - The future of cancer immunotherapy

The BTLA-HVEM complex plays a pivotal role in cancer and cancer immunotherapy by regulating immune responses. Dysregulation of BTLA and HVEM expression contributes to immunosuppression and tumor progression across various cancer types. Targeting the interaction between BTLA and HVEM holds promise for enhancing anti-tumor immune responses. Disruption of this complex presents a valuable avenue for advancing cancer immunotherapy strategies. Aberrant expression of BTLA and HVEM adversely affects immune cell function, particularly T cells, exacerbating tumor evasion mechanisms. Understanding and modulating the BTLA-HVEM axis represents a crucial aspect of designing effective immunotherapeutic interventions against cancer. Here, we summarize the current knowledge regarding the structure and function of BTLA and HVEM, along with their interaction with each other and various immune partners. Moreover, the expression of soluble and transmembrane forms of BTLA and HVEM in different types of cancer and their impact on the prognosis of patients is also discussed. Additionally, inhibitors of the proteins binding that might be used to block BTLA-HVEM interaction are reviewed. All the presented data highlight the plausible clinical application of BTLA-HVEM targeted therapies in cancer and autoimmune disease management. However, further studies are required to confirm the practical use of this concept. Despite the increasing number of reports on the BTLA-HVEM complex, many aspects of its biology and function still need to be elucidated. This review can be regarded as an encouragement and a guide to follow the path of BTLA-HVEM research.

LIGHT-HVEM signaling in keratinocytes controls development of dermatitis

Factors that control skin inflammation are still being defined. Herro et al. demonstrate that the tumor necrosis factor superfamily protein LIGHT acts on keratinocytes via its receptor HVEM to promote characteristic features of atopic dermatitis, including epidermal hyperplasia and production of periostin.

Dermatitis is often associated with an allergic reaction characterized by excessive type 2 responses leading to epidermal acanthosis, hyperkeratosis, and dermal inflammation. Although factors like IL-4, IL-13, and thymic stromal lymphopoietin (TSLP) are thought to be instrumental for the development of this type of skin disorder, other cytokines may be critical. Here, we show that the tumor necrosis factor (TNF) superfamily protein LIGHT (homologous to lymphotoxin, exhibits inducible expression, and competes with HSV glycoprotein D for binding to HVEM, a receptor expressed on T lymphocytes) is required for experimental atopic dermatitis, and LIGHT directly controls keratinocyte hyperplasia, and production of periostin, a matricellular protein that contributes to the clinical features of atopic dermatitis as well as other skin diseases such as scleroderma. Mice with a conditional deletion of the LIGHT receptor HVEM (herpesvirus entry mediator) in keratinocytes phenocopied LIGHT-deficient mice in exhibiting reduced epidermal thickening and dermal collagen deposition in a model of atopic dermatitis driven by house dust mite allergen. LIGHT signaling through HVEM in human epidermal keratinocytes directly induced proliferation and periostin expression, and both keratinocyte-specific deletion of HVEM or antibody blocking of LIGHT–HVEM interactions after disease onset prevented expression of periostin and limited atopic dermatitis symptoms. Developing reagents that neutralize LIGHT–HVEM signaling might be useful for therapeutic intervention in skin diseases where periostin is a central feature.

The paradoxical changes of membrane and soluble herpes virus entry mediator in hepatocellular carcinoma patients

BACKGROUND AND AIM

The herpes virus entry mediator (HVEM) network has become new directions in targeting novel checkpoint inhibitors for cancer therapy. However, the changes of membrane-bound HVEM (mHVEM) and soluble HVEM (sHVEM) in hepatocellular carcinoma (HCC) are not fully understood. This study aims to study the changes of mHVEM and sHVEM in HCC patients.

METHODS

Serum samples were collected from 65 HCC patients, from which sHVEM levels were examined by enzyme-linked immunosorbent assay. Expressions of mHVEM on peripheral lymphocytes from 20 HCC patients were determined using flow cytometry, and associations between mHVEM on T and B cells were analyzed.

RESULTS

The levels of mHVEM were downregulated on peripheral lymphocytes in HCC patients, with a strong positive correlation between mHVEM expression on T and B cells. In contrast, the levels of soluble HVEM were upregulated in the serum of HCC patients. Furthermore, we found that the increase in sHVEM level was correlated with advanced stages HCC.

CONCLUSION

Our data demonstrated paradoxical changes of membrane and soluble HVEM in the peripheral blood of HCC patients for the first time. These data supported the notion that roles of HVEM are likely to be immunosuppressive rather than activating tumor immunity. Future studies are warranted to further explore the translational values of mHVEM and sHVEM in peripheral blood as diagnostic markers and therapeutic targets.