Horse IL-2 ELISA Kit

Minimal residual disease (MRD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) heralds high risk of relapse. Whether preemptive recombinant interleukin-2 (pre-IL2) is effective for patients with late-onset MRD (LMRD) remains unknown. We retrospectively compared the efficacy and safety of pre-IL2 (n = 30) and pre-DLI (n = 25) for LMRD in patients receiving allo-HSCT for acute leukemia or myelodysplastic syndrome. The 1-year overall survival (OS) and disease-free survival (DFS) rates were 86.7% and 78.4% (P = 0.267), 83.3% and 75.6% (P = 0.329), the cumulative incidence of grades III-IV acute graft-versus-host disease (aGVHD) at 100 days post-preemptive intervention was 3.3% and 12.0% (P = 0.226) in the pre-IL2 group and pre-DLI group, respectively. The 1-year cumulative incidence of moderate/severe chronic GVHD (cGVHD), relapse (CIR), and non-relapse mortality (NRM) were 7.7% and 27.9% (P = 0.018), 13.6% and 20.0% (P = 0.561) and 3.3% and 5.5% (P = 0.321) in the two groups, respectively. No remarkable differences in CIR, OS, and DFS between the two intervention groups were found in multivariate analysis. The GVHD-free and relapse-free survival (GRFS) were better in the pre-IL2 group than in the pre-DLI group (HR = 0.31, 95% confidence interval (CI), 0.12-0.76; P = 0.011). In conclusion, preemptive low-dose IL2 and preemptive DLI yield comparable outcomes for patients with LMRD receiving allo-HSCT, in terms of aGVHD, NRM, relapse, OS, and DFS. However, preemptive low-dose IL2 has a lower incidence of moderate/severe cGVHD and a higher CRFS. Preemptive low-dose IL2 may be an alternative method for patients who develop LMRD after allo-HSCT, particularly for patients who cannot receive preemptive DLI.

Background: The mouse strains usually used to generate patient-derived xenografts (PDXs) are immunocompromised, rendering them unsuitable for immunotherapy studies. Here we assessed the value of immune-PDX mouse models for predicting responses to anti-PD-1 checkpoint inhibitor therapy in patients. Patients and methods: Melanoma biopsies contained in a retrospective biobank were transplanted into NOG mice or NOG mice expressing interleukin 2 (hIL2-NOG mice). Tumor growth was monitored, and comparisons were made with clinical data, sequencing data, and current in silico predictive tools. Results: Biopsies grew readily in NOG mice but growth was heterogeneous in hIL2-NOG mice. IL2 appears to activate T-cell immunity in the biopsies to block tumor growth. Biopsy growth in hIL2-NOG mice was negatively associated with survival in patients previously treated with PD-1 checkpoint blockade. In two cases, the prospective clinical decisions of anti-PD-1 therapy or targeted BRAF/MEK inhibitors were supported by the observed responses in mice. Conclusions: Immune-PDX models represent a promising addition to future biomarker discovery studies and for clinical decision making in patients receiving immunotherapy.