GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE330nnn/GSE330395/primaryOK200Methylation profilingHomo sapiensMethylation profiling by genome tiling arrayhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE330395GEOGSEfalseClinical development of tacrolimus-resistant regulatory T cells to enable simultaneous immunosuppression and support of immune regulationUnwanted alloimmune responses are a central driver of solid organ transplant rejection and currently managed with life-long immunosuppression, which imposes substantial risks and burdens on patients. Adoptive transfer of regulatory T cells (Tregs) offers a strategy to restore immunological balance and reduce long-term adverse effects of generalized immunosuppression. However, while Tregs can potently inhibit incipient immune activation, they struggle to suppress established memory effector T cells, necessitating the continued use of immunosuppression. Calcineurin inhibitors such as Tacrolimus effectively control both, newly activated and pre-existing effector-T-cells, but unfortunately, they also impair Treg function. Therefore, we hypothesized that gene-editing of Tregs inducing Tacrolimus resistance (FKBP12KO) would enable combined therapy that curbs effector T-cell responses without compromising Treg efficacy. Here, we developed FKBP12KO-Tregs using a ribonucleoprotein-based CRISPR/Cas9 approach and characterized them extensively in-vitro. FKBP12KO-Tregs retained phenotype, high viability, and suppressive function comparable to unedited TregWT and they remained functionally impervious to Tacrolimus, while preserving sensitivity to alternative CNIs. We additionally established a Good-Manufacturing-Practice process for FKBP12KO-Tregs. Comprehensive in vitro phenotypic, functional, and molecular characterization, together with the established manufacturing, provide the rationale for a proof-of- concept clinical trial assessing the feasibility and safety of co-administration of FKBP12KO-Tregs with Tacrolimus in living-donor kidney transplant recipients.2026/06/11GSE330395GSM9725320GSM9725321GSM9725310GSM9725311GSM9725322GSM9725312GSM9725313GSM9725314GSM9725315GSM9725316GSM9725317GSM9725318GSM9725307GSM9725319GSM9725308GSM972530921145330395Homo sapiens