Low Immunogenicity of Keratinocytes Derived from Human Embryonic Stem Cells.

Epidermal transplantation is a common and widely used surgical technique in clinical medicine. Derivatives of embryonic stem cells have the potential to serve as a source of transplantable cells. However, allograft rejection is one of the main challenges. To investigate the immunogenicity of keratinocytes derived from human embryonic stem cells (ESKCs), we conducted a series of in vivo and in vitro experiments. The results showed that ESKCs have low HLA molecule expression, limited antigen presentation capabilities, and a weak ability to stimulate the proliferation and secretion of inflammatory factors in allogeneic PBMCs in vitro. In humanized immune mouse models, ESKCs elicited weak transplant rejection responses in the host. Overall, we found that ESKCs have low immunogenicity and may have potential applications in the field of regenerative medicine.

The Treatment of Refractory Vitiligo With Autologous Cultured Epithelium Grafting: A Real-World Retrospective Cohort Study.

BACKGROUND: Surgical intervention is the main therapy for refractory vitiligo. We developed a modified autologous cultured epithelial grafting (ACEG) technique for vitiligo treatment. Between January 2015 and June 2019, a total of 726 patients with vitiligo underwent ACEG in China, with patient characteristics and clinical factors being meticulously documented. Using a generalized linear mixed model, we were able to assess the association between these characteristics and the repigmentation rate. RESULTS: ACEG demonstrated a total efficacy rate of 82.81% (1754/2118) in treating 726 patients, with a higher repigmentation rate of 64.87% compared to conventional surgery at 52.69%. Notably, ACEG showed a better response in treating segmental vitiligo, lesions on lower limbs, age ≤ 18, and stable period > 3 years. A keratinocyte:melanocyte ratio below 25 was found to be advantageous too. Single-cell RNA sequencing analysis revealed an increase in melanocyte count and 2 subclusters of keratinocytes after ACEG, which remained higher in repigmented sites even after 1 year. CONCLUSIONS: ACEG is a promising therapy for refractory vitiligo. Patient age, clinical type, lesion site, and stability before surgery influence repigmentation in ACEG. The mechanism of repigmentation after ACEG treatment is likely not confined to the restoration of melanocyte populations. It may also involve an increase in the number of keratinocytes that support melanocyte function within the affected area. These keratinocytes may aid the post-transplant survival and function of melanocytes by secreting cytokines and extracellular matrix components. TRIAL REGISTRATION: registered with Chictr.org.cn (ChiCTR2100051405).

Comprehensive Analysis of Cuproptosis-Related Genes in Immune Infiltration and Prognosis in Melanoma.

Skin cutaneous melanoma (SKCM, hereafter referred to as melanoma) is the most lethal skin cancer with increasing incidence. Regulated cell death plays an important role in tumorigenesis and serves as an important target for almost all treatment strategies. Cuproptosis is the most recently identified copper-dependent regulated cell death form that relies on mitochondria respiration. However, its role in tumorigenesis remains unknown. The correlation of cuproptosis-related genes with tumor prognosis is far to be understood, either. In the present study, we explored the correlation between cuproptosis-related genes with the prognosis of melanoma by accessing and analyzing a public database and found 11 out 12 genes were upregulated in melanoma tissues and three genes (LIPT1, PDHA1, and SLC31A1) have predictive value for the prognosis. The subgroup of melanoma patients with higher cuproptosis-related gene expression showed longer overall survival than those with lower gene expression. We chose LIPT1 for further exploration. LIPT1 expression was increased in melanoma biopsies and was an independent favorable prognostic indicator for melanoma patients. Moreover, LIPT1 expression was positively correlated with PD-L1 expression and negatively associated with Treg cell infiltration. The melanoma patients with higher LIPT1 expression showed longer overall survival than those with lower LIPT1 expression after receiving immunotherapy, indicating the prognostic predictive value of LIPT1. Finally, a pan-cancer analysis indicated that LIPT1 was differentially expressed in diverse cancers as compared to normal tissues and correlated with the expression of multiple immune checkpoints, especially PD-L1. It could serve as a favorable prognosis indicator in some cancer types. In conclusion, our study demonstrated the prognostic value of cuproptosis-related genes, especially LIPT1, in melanoma, and revealed the correlation between LIPT1 expression and immune infiltration in melanoma, thus providing new clues on the prognostic assessment of melanoma patients and providing a new target for the immunotherapy of melanoma.

Human embryonic stem cell-derived melanocytes exhibit limited immunogenicity.

Although surgical interventions have become optional for refractory vitiligo, grafting related injuries is inevitable. Embryonic stem cell (ESC) derivatives can be used in transplantation to address this issue, but the immune rejection due to allogeneic transplantation is of great concern. To investigate the immunogenicity of ESC derived melanocytes (ES-MC), we established a co-culture system of ES-MC and allogeneic PBMC. The results showed that ES-MC were similar to human primary melanocytes, with low expression of immune related molecules, and limited capability of stimulating allogeneic lymphocytes in vitro. Taken together, our findings confirm that ES-MC are of limited immunogenicity, providing new insights into the application of ES-MC in the regenerative medicine such as treating vitiligo.