Search PubMedSearch

Biomedical subjects

Li Wan

Publications and source records attributed to Li Wan.

2 recordsLinked to original sources

Day + 30 detection of minimal residual FLT3-ITD by high-sensitivity PCR-NGS predicts relapse risk and guides post-transplant maintenance in AML.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved outcomes in patients with acute myeloid leukemia (AML) harboring FLT3-internal tandem duplication (FLT3-ITD) mutations. However, relapse still occurs in 15-35% of these patients after transplantation. Therefore, early and highly sensitive detection methods are required to identify patients at risk of relapse and enable timely post-transplant intervention. METHODS: In this NICHE cohort study, a total of 136 patients were included, then we evaluated whether high-sensitivity polymerase chain reaction (PCR)-next-generation sequencing (NGS) for FLT3-ITD (limit of detection: 5 × 10-6) on day + 30 post-HSCT could identify patients at a high risk of relapse and inform decisions regarding maintenance therapy. RESULTS: Among the 136 patients, 37 patients (27.2%) had detectable FLT3-ITD clones on day + 30. These patients exhibited a significantly higher cumulative incidence of post-HSCT multiparameter flow cytometry (MFC)-measurable residual disease (MRD) relapse (40.3% vs. 18.8%, p = 0.001). Notably, FLT3-ITD-positive patients who received FLT3 inhibitor maintenance therapy had no relapses, while 6 out of the 13 patients who did not receive maintenance therapy relapsed. Conversely, FLT3-ITD-negative patients without high-risk factors (2022 European LeukemiaNet adverse-risk group, relapsed/refractory AML, MFC-MRD positivity pre-HSCT) showed limited benefit from maintenance therapy (MFC-MRD-free survival: hazard ratio (HR) = 0.25 (0.03-2.11), p = 0.204; OS: HR = 0.20 (0.02-1.70), p = 0.142). CONCLUSIONS: This is the first study to demonstrate that detection of minimal FLT3-ITD clones at the fixed time point of day + 30 post-HSCT can reliably stratify relapse risk in AML patients and provide a rationale for individualized post-transplant maintenance therapy.

Humans

The Arabidopsis TIRome informs the design of artificial TIR (Toll/interleukin-1 receptor) domain proteins.

The TIR (Toll/interleukin-1 receptor) domain is an ancient protein module that functions in immune and cell death responses across the Tree of Life. TIR domains encoded by plants and prokaryotes function as enzymes to produce diverse small molecule immune signals. Plant genomes can encode hundreds of TIR-domain containing proteins-many of which confer important agricultural disease resistance as TIR-NLR (nucleotide-binding, leucine-rich repeat) immune receptors. Despite their importance, how natural variation influences TIR enzymatic output and immunity-associated cell death is largely unexplored. We assayed a complete collection of the TIR domains of Arabidopsis thaliana Col-0 (the "AtTIRome") to explore variation in TIR metabolite production and cell death signaling. Roughly half of the AtTIRome triggered cell death in transient assays. Artificial TIR proteins designed based on consensus sequences of the AtTIRome's cell death phenotypic classes revealed polymorphisms controlling variation in TIR cell death elicitation and metabolite production. Structure-function analyses of artificial TIRs revealed that natural variation in the "BB-loop", a flexible region overlying the catalytic pocket, determines differences in function across Arabidopsis TIR-containing proteins. We further demonstrate that artificial TIRs are functional on an NLR chassis and that BB-loop variation can tune the activity of a natural TIR-NLR protein. These findings shed light on the diversity of TIR outputs and reveal methods to design and engineer TIR-based immune receptors.

Arabidopsis