To identify potential early biomarkers of treatment response and immune-related adverse events (irAE), a pilot immune monitoring study was performed in stage IV melanoma patients by flow cytometric analysis of peripheral blood mononuclear cells (PBMC). Overall, 17 patients were treated with either nivolumab or pembrolizumab alone, or with a combination of nivolumab and ipilimumab every three weeks. Of 15 patients for which complete response assessment was available, treatment responders (n = 10) as compared to non-responders (n = 5) were characterized by enhanced PD-1 expression on CD8⁺ T cells immediately before treatment (median ± median absolute deviation/MAD 26.7 ± 10.4% vs. 17.2 ± 5.3%). Responders showed a higher T cell responsiveness after T cell receptor ex vivo stimulation as determined by measurement of programmed cell death 1 (PD-1) expression on CD3⁺ T cells before the second cycle of treatment. The percentage of CD8⁺ effector memory (CD8⁺CD45RA⁻CD45RO⁺CCR7⁻) T cells was higher in responders compared to non-responders before and immediately after the first cycle of treatment (median ± MAD 39.2 ± 7.3% vs. 30.5 ± 4.1% and 37.7 ± 4.6 vs. 24.0 ± 6.4). Immune-related adverse events (irAE) were accompanied by a higher percentage of activated CD4⁺ (CD4⁺CD38⁺HLADR⁺) T cells before the second treatment cycle (median ± MAD 14.9 ± 3.9% vs. 5.3 ± 0.4%). In summary, PBMC immune monitoring of immune-checkpoint inhibition (ICI) treatment in melanoma appears to be a promising approach to identify early markers of treatment response and irAEs.

Wound healing of acute full-thickness injuries and chronic non-healing ulcers leads to delayed wound closure, prolonged recovery period and hypertrophic scarring, generating a demand for an autologous cell therapy and a relevant pre-clinical research models for wound healing. In this study, an immunocompetent model for wound healing was employed using a syngeneic murine cell line of mesenchymal stem cells cultured from the mouse whisker hair follicle outer root sheath (named moMSCORS). moMSCORS were isolated using an air-liquid interface method, expanded in vitro and characterized according to the MSC definition criteria - cell viability, in vitro proliferation, MSC phenotype and multi-lineage differentiations. Moreover, upon applying moMSCORS in an in vivo full-thickness wound model in the syngeneic C57BL/6 mice, the treated wounds displayed different morphology to that of the untreated wound beds. Quantitative evaluation of angiogenesis, granulation and wound closure involving clinical scoring and software-based quantification indicated a lower degree of inflammation in the treated wounds. Histological staining of treated wounds by the means of H&E, Alcian Blue, PicroSirius Red and αSMA immune labelling showed lower cellularity, less collagen filaments as well as thinner dermal and epidermal layers compared with the untreated wounds, indicating a general reduction of hypertrophic scars. The decreased inflammation, accelerated wound closure and non-hypertrophic scarring, which were facilitated by moMSCORS, hereby address a common problem of hypertrophic scars and non-physiological tissue properties upon wound closure, and additionally offer an in vivo model for the autologous cell-based wound healing. Graphic Abstract

Inflammatory diseases including psoriasis are associated with metabolic and cardiovascular comorbidities, including obesity and metabolic syndrome. Obesity is associated with greater psoriasis disease severity and reduced response to treatment. Therefore, targeting metabolic comorbidities could improve patients’ health status and psoriasis-specific outcomes. METABOLyx is a randomized controlled trial evaluating the combination of a lifestyle intervention program with secukinumab treatment in psoriasis. Here, the rationale, methodology and baseline patient characteristics of METABOLyx are presented. A total of 768 patients with concomitant moderate to severe plaque psoriasis and metabolic syndrome were randomized to secukinumab 300 mg, or secukinumab 300 mg plus a tailored lifestyle intervention program, over 24 weeks. A substudy of immunologic and metabolic biomarkers is ongoing. The primary endpoint of METABOLyx is PASI90 response at week 24. Other endpoints include patient-reported outcomes and safety. METABOLyx represents the first large scale clinical trial of an immunomodulatory biologic in combination with a standardized lifestyle intervention.

Hair follicle outer root sheath (ORS) is a putative source of stem cells with therapeutic capacity. ORS contains several multipotent stem cell populations, primarily in the distal compartment of the bulge region. However, the bulge is routinely obtained using invasive isolation methods, which require human scalp tissue ex vivo. Non-invasive sampling has been standardized by means of the plucking procedure, enabling to reproducibly obtain the mid-ORS part. The mid-ORS shows potential for giving rise to multiple stem cell populations in vitro. To demonstrate the phenotypic features of distal, middle, and proximal ORS parts, gene and protein expression profiles were studied in physically separated portions. The mid-part of the ORS showed a comparable or higher NGFR, nestin/NES, CD34, CD73, CD44, CD133, CK5, PAX3, MITF, and PMEL expression on both protein and gene levels, when compared to the distal ORS part. Distinct subpopulations of cells exhibiting small and round morphology were characterized with flow cytometry as simultaneously expressing CD73/CD271, CD49f/CD105, nestin, and not CK10. Potentially, these distinct subpopulations can give rise to cultured neuroectodermal and mesenchymal stem cell populations in vitro. In conclusion, the mid part of the ORS holds the potential for yielding multiple stem cells, in particular mesenchymal stem cells.