Molecular Scarring in Relapsing Psoriasis: Crosstalk of Keratinocytes and Immune Cells

Abstract Introduction/Objective Psoriasis is a chronic skin disorder with a tendency for relapse, characterized by immune- mediated mechanisms leading to papulosquamous lesions. Despite advances in treatment, many patients experience relapse, particularly in previously healed areas, referred to as “molecular scarring.” This scarring suggests a complex interaction between keratinocytes and immune cells, including tissue-resident memory T cells (TRMs), cytokines, and epigenetic modifications, contributing to the pattern-specific recurrence of psoriasis. Methods/Case Report After reviewing 31 articles on PubMed, we focused on the immunopathogenesis of psoriasis, examining the role of TRMs, the balance between regulatory T cells (Tregs) and Th17 cells, and the impact of various treatment modalities on disease recurrence. It evaluates the expression of TRM markers and the effectiveness of treatments such as anti-IL-17 agents and phototherapy in altering disease progression. The study also explores the genomic characteristics of psoriatic lesions post-treatment and the duration of clinical remission associated with different therapeutic approaches. Results (if a Case Study enter NA) The findings demonstrate a significant role of TRMs in psoriasis relapse, with environmental triggers reactivating these cells and leading to the production of inflammatory cytokines. Treatments targeting IL-17 showed a rapid decrease in TRM markers, particularly in the dermis, and were associated with different durations of disease remission based on the therapeutic approach. The study also found that the genomic profile of treated lesions does not fully normalize, with variations in gene expression linked to the type of treatment and possibly influencing the size of the molecular scar and relapse duration. Conclusion Psoriasis relapse is intricately linked to the presence of TRMs and the molecular scarring of previously healed lesions, influenced by various treatment modalities. The study underscores the importance of targeting TRMs and adjusting therapeutic strategies to extend the period of clinical remission and prevent the transition to more severe disease forms. Future research should focus on elucidating the detailed mechanisms of psoriasis relapse and developing targeted treatments to normalize the genomic profile of healed skin, ultimately improving patient outcomes and management of the disease.