Targeting Melanoma-Associated Fibroblasts (MAFs) with Activated γδ (Vδ2) T Cells: An In Vitro Cytotoxicity Model

The tumor microenvironment (TME) has gained considerable scientific attention by playing a role in immunosuppression and tumorigenesis. Besides tumor cells, TME is composed of various other cell types, including cancer-associated fibroblasts (CAFs or MAFs when referring to melanoma-derived CAFs) and tumor-infiltrating lymphocytes (TILs), a subpopulation of which is labeled as γδ T cells. Since the current anti-cancer therapies using γδ T cells in various cancers have exhibited mixed treatment responses, to better understand the γδ T cell biology in melanoma, our research group aimed to investigate whether activated γδ T cells are capable of killing MAFs. To answer this question, we set up an in vitro platform using freshly isolated Vδ2-type γδ T cells and cultured MAFs that were biobanked from our melanoma patients. This study proved that the addition of zoledronic acid (1-2.5 µM) to the γδ T cells was necessary to drive MAFs into apoptosis. The MAF cytotoxicity of γδ T cells was further enhanced by using the stimulatory clone 20.1 of anti-BTN3A1 antibody but was reduced when anti-TCR γδ or anti-BTN2A1 antibodies were used. Since the administration of zoledronic acid is safe and tolerable in humans, our results provide further data for future clinical studies on the treatment of melanoma.

Szemészeti érintettséggel járó paraneoplasiás pemphigoid

Összefoglaló. A nyálkahártya-pemphigoid különleges formája a paraneoplasiás pemphigoid, amely primer malignus betegséghez társul; lefolyása szokatlanul gyors, és a klasszikus immunszuppresszív terápiákkal szemben rezisztens lehet. Közleményünkben három eseten keresztül mutatjuk be a paraneoplasiás pemphigoid megjelenését, diagnosztikáját és a terápiás kihívásokat. A diagnózist a kórelőzményi adatok és az immunfluoreszcens vizsgálatok segítik. A terápiás célkitűzés a progresszió lassítása immunszuppresszív kezeléssel, amely a zajló onkológiai kezelés mellett kontraindikált lehet. Tekintettel arra, hogy jelenleg nincs konszenzus ennek a ritka kórképnek a diagnosztikájában és kezelésében, különösen fontos, hogy a társszakmák (szemészet, bőrgyógyászat, fogászat, fül-orr-gégészet, onkológia, immunológia) együttműködésével a betegség minél hamarabb felismerhető legyen, és a kezelést ezáltal minél korábban el lehessen kezdeni. Orv Hetil. 2022; 163(18): 720–725.

Summary. Paraneoplastic mucous membrane pemphigoid, a rare pemphigoid variant is associated with primary malignancy, and characterised by fulminant progression and frequent ineffectivity of classical systemic immunosuppression. In this paper, the clinical features, diagnostic and therapeutical challenges are presented through three cases. Detailed history and analysis of the immunofluorescent samples help the diagnosis. The therapeutic goal is to prevent the progression with systemic immunosuppressive treatment, which can be contraindicated during the ongoing oncological therapy. In absence of consent in the exact diagnostic criteria and management protocol of this rare condition, consultation with other specialists (ophthalmologist, dermatologist, dentist, ear-nose-throat specialist, immunologist) has high importance in early diagnosis and treatment. Orv Hetil. 2022; 163(18): 720–725.

Melanoma-associated fibroblasts impair CD8+ T cell function and modify expression of immune checkpoint regulators via increased arginase activity

Abstract

This study shows that melanoma-associated fibroblasts (MAFs) suppress cytotoxic T lymphocyte (CTL) activity and reveals a pivotal role played by arginase in this phenomenon. MAFs and normal dermal fibroblasts (DFs) were isolated from surgically resected melanomas and identified as Melan-A-/gp100-/FAP+ cells. CTLs of healthy blood donors were activated in the presence of MAF- and DF-conditioned media (CM). Markers of successful CTL activation, cytotoxic degranulation, killing activity and immune checkpoint regulation were evaluated by flow cytometry, ELISPOT, and redirected killing assays. Soluble mediators responsible for MAF-mediated effects were identified by ELISA, flow cytometry, inhibitor assays, and knock-in experiments. In the presence of MAF-CM, activated/non-naïve CTLs displayed dysregulated ERK1/2 and NF-κB signaling, impeded CD69 and granzyme B production, impaired killing activity, and upregulated expression of the negative immune checkpoint receptors TIGIT and BTLA. Compared to DFs, MAFs displayed increased amounts of VISTA and HVEM, a known ligand of BTLA on T cells, increased l-arginase activity and CXCL12 release. Transgenic arginase over-expression further increased, while selective arginase inhibition neutralized MAF-induced TIGIT and BTLA expression on CTLs. Our data indicate that MAF interfere with intracellular CTL signaling via soluble mediators leading to CTL anergy and modify immune checkpoint receptor availability via l-arginine depletion.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00018-020-03517-8) contains supplementary material, which is available to authorized users.

Skin-homing CD8+ T cells preferentially express GPI-anchored peptidase inhibitor 16, an inhibitor of cathepsin K

This study sought to identify novel CD8⁺ T cell homing markers by studying acute graft versus host disease (aGvHD), typically involving increased T cell homing to the skin and gut. FACS-sorted skin-homing (CD8β⁺ /CLA⁺ ), gut-homing (CD8β⁺ /integrinβ7⁺ ), and reference (CD8β⁺ /CLA^- /integrinβ7^- ) T cells were compared in patients affected by cutaneous and/or gastrointestinal aGVHD. Microarray analysis, qPCR, and flow cytometry revealed increased expression of peptidase inhibitor 16 (PI16) in skin-homing CD8⁺ T cells. Robust association of PI16 with skin homing was confirmed in all types of aGvHD and in healthy controls, too. PI16 was not observed on CLA⁺ leukocytes other than T cells. Induction of PI16 expression on skin-homing T cells occurred independently of vitamin D3. Among skin-homing T cells, PI16 expression was most pronounced in memory-like CD45RO⁺ /CD127⁺ /CD25⁺ /CD69^- /granzyme B^- cells. PI16 was confined to the plasma membrane, was GPI-anchored, and was lost upon restimulation of memory CD8⁺ T cells. Loss of PI16 occurred by downregulation of PI16 transcription, and not by Phospholipase C (PLC)- or Angiotensin-converting enzyme (ACE)-mediated shedding, or by protein recycling. Inhibitor screening and pull-down experiments confirmed that PI16 inhibits cathepsin K, but may not bind to other skin proteases. These data link PI16 to skin-homing CD8⁺ T cells, and raise the possibility that PI16 may regulate cutaneous cathepsin K.

[Epidermolysis bullosa: oral manifestations and their treatments]

The aim of this comprehensive article is to provide guidelines for the daily treatment of patients with epidermolysis bullosa, thus contributing to the attainment of their higher quality of life through the improvement of their oral health. Moreover, it is our intention to facilitate the cooperation among Hungarian general practitioners, dermatologists and dentists. Relying on recent research findings of the international literature, we intend to help general practitioners or dermatologists treating epidermolysis bullosa patients on a daily basis by identifying symptoms that require consulting an oral professional on the one hand, and to present the most important prevention strategies and further treatments advised for dentists on the other. Focusing on various aspects of dental treatment, we specify how a dentist can treat the patient without causing additional wounds or pain, and what kinds of therapy are justified by this approach. Orv Hetil. 2017; 158(40): 1577-1583.

A unique LAMB3 splice-site mutation with founder effect from the Balkans causes lethal epidermolysis bullosa in several European countries

BACKGROUND

We have encountered repeated cases of recessive lethal generalized severe (Herlitz-type) junctional epidermolysis bullosa (JEB gen sev) in infants born to Hungarian Roma parents residing in a small region of Hungary.

OBJECTIVES

To identify the disease-causing mutation and to investigate the genetic background of its unique carrier group.

METHODS

The LAMB3 gene was analysed in peripheral-blood genomic DNA samples, and the pathological consequences of the lethal defect were confirmed by cutaneous LAMB3cDNA sequencing. A median joining haplotype network within the Y chromosome H1a-M82 haplogroup of individuals from the community was constructed, and LAMB3 single-nucleotide polymorphism (SNP) patterns were also determined.

RESULTS

An unconventional intronic splice-site mutation (LAMB3, c.1133-22G>A) was identified. Thirty of 64 voluntarily screened Roma from the closed community carried the mutation, but none of the 306 Roma from other regions of the country did. The age of the mutation was estimated to be 548 ± 222 years. Within the last year, more patients with JEB gen sev carrying the same unusual mutation have been identified in three unrelated families, all immigrants from the Balkans. Two were compound heterozygous newborns, in Germany and Italy, and one homozygous newborn died in France. Only the French family recognized their Roma background. LAMB3SNP haplotyping confirmed the link between the apparently unrelated Hungarian, German and Italian male cases, but could not verify the same background in the female newborn from France.

CONCLUSIONS

The estimated age of the mutation corresponds to the time period when Roma were wandering in the Balkans.

[Role of cancer stem cells in the progression and heterogeneity of melanoma]

Over the past decade a rare cell population called cancer stem cells has been identified in both solid tumors and hematologic cancers. These cells are reminiscent of somatic and embryonic stem cells and play a critical role in the initiation and progression of malignancies. As all stem cells, they are able to undergo asymmetric cell division and hence renew themselves and create various other progenies with heterogenous phenotypes. A growing body of literature suggested that stem cell subpopulations contribute significantly to the growth and metastatic properties of melanoma. This review gives a comprehensive overview of the current literature on melanoma stem cells, with a special emphasis on the signaling pathways responsible for the homeostatic growth of melanocytes and the uncontrolled proliferation of melanoma cells. The importance of the local microenvironment are demonstrated through summarizing the role of various cell types, soluble factors and cell adhesion molecules in the progression of melanoma and the creation of treatment resistant cancer cell clones. Last but not least, the models of melanoma progression will be introduced and a variety of cellular markers will be presented that may be used to identify and therapeutically target melanoma. Orv. Hetil., 2016, 157(34), 1339-1348.

Characterization of desmoglein-3 epitope region peptides as synthetic antigens: analysis of their in vitro T cell stimulating efficacy, cytotoxicity, stability, and their conformational features

Desmoglein-3 (Dsg3) adhesion protein is the main target of autoantibodies and autoreactive T cells in Pemphigus vulgaris (PV) autoimmune skin disorder. Several mapping studies of Dsg3 T cell epitope regions were performed, and based on those data, we designed and synthesized four peptide series corresponding to Dsg3 T cell epitope regions. Each peptide series consists of a 17mer full-length peptide (Dsg3/189-205, Dsg3/206-222, Dsg3/342-358, and Dsg3/761-777) and its N-terminally truncated derivatives, resulting in 15 peptides altogether. The peptides were prepared on solid phase and were chemically characterized. In order to establish a structure-activity relationship, the solution conformation of the synthetic peptides has been investigated using electronic circular dichroism spectroscopy. The in vitro T cell stimulating efficacy of the peptides has been determined on peripheral blood mononuclear cells isolated from whole blood of PV patients and also from healthy donors. After 20 h of stimulation, the interferon (IFN)-γ content of the supernatants was measured by enzyme-linked immunosorbent assay. In the in vitro conditions, peptides were stable and non-cytotoxic. The in vitro IFN-γ production profile of healthy donors and PV patients, induced by peptides as synthetic antigens, was markedly different. The most unambiguous differences were observed after stimulation with 17mer peptide Dsg3/342-358, and three truncated derivatives from two other peptide series, namely, peptides Dsg3/192-205, Dsg3/763-777, and Dsg3/764-777. Comparative analysis of in vitro activity and the capability of oligopeptides to form ordered or unordered secondary structure showed that peptides bearing high solvent sensibility and backbone flexibility were the most capable to distinguish between healthy and PV donors.

Evidence for a role of autoantibodies to heat shock protein 60, 70, and 90 in patients with dermatitis herpetiformis

Heat shock proteins (Hsp) are highly conserved immunomodulatory molecules upregulated when cells are exposed to stressful stimuli, such as inflammation. Their involvement in various autoimmune diseases, including autoimmune bullous diseases and celiac disease, has been increasingly recognized. To further study the role of Hsp in autoimmune bullous diseases, we have investigated for the first time the humoral autoimmune response to Hsp40, Hsp60, Hsp70, and Hsp90 in patients with dermatitis herpetiformis (DH; n = 26), bullous pemphigoid (BP; n = 23), and pemphigus vulgaris (PV; n = 16), the first representing a cutaneous manifestation of celiac disease. While in patients with active BP and PV, serum levels of autoantibodies against these Hsp did not differ from the corresponding age- and gender-matched healthy controls (n = 9-14); circulating autoantibodies against Hsp60, Hsp70, and Hsp90 were found to be increased at the active disease stage of DH. Further analysis of this latter patient subgroup showed that these anti-Hsp autoantibodies decreased in parallel with serum autoantibodies against epidermal and tissue transglutaminase during remission of skin lesions following a gluten-free diet, revealing significantly positive correlations. Although further studies on larger groups of patients will be needed to confirm the present data, our results support the notion that autoantibodies against Hsp60, Hsp70, and Hsp90 deserve attention in the study of the mechanisms that promote the development and maintenance of DH and possibly also the underlying celiac disease as well as potential novel disease biomarkers.

[Radical vulvectomy to treat severe vulvar acne inversa]

A rare case, when radical vulvectomy had to be done to treat a benign skin disorder is presented.

PATIENT AND METHOD

A 56-year-old white woman suffered from severe vulvar acne inversa. The systemic treatments, the incisions and drainages were not successful. The only solution was the radical excision of the seriously damaged vulva, with a satisfactory cosmetic and functional result. The pathology, the diagnosis and the treatment of the disease are also discussed.

CONCLUSION

The authors put emphasis on the importance of the interdisciplinary collaboration.