Normanhein6197
Early immunological biomarkers that predict rejection and chronic allograft loss are needed to inform preemptive therapy and improve long-term outcomes. Here, we prospectively examined the ratio of interleukin-10 (IL-10) to tumor necrosis factor-α (TNFα) produced by transitional-1 B cells (T1B) 3 months after transplantation as a predictive biomarker for clinical and subclinical renal allograft rejection and subsequent clinical course. In both Training (n = 162) and Internal Validation (n = 82) Sets, the T1B IL-10/TNFα ratio 3 months after transplantation predicted both clinical and subclinical rejection anytime in the first year. The biomarker also predicted subsequent late rejection with a lead time averaging 8 months. Among biomarker high-risk patients, 60% had early rejection, of which 48% recurred later in the first posttransplant year. Among high-risk patients without early rejection, 74% developed rejection later in the first year. In contrast, only 5% of low-risk patients had early and 5% late rejection. The biomarker also predicted rejection in an External Validation Set (n = 95) and in key patient subgroups, confirming generalizability. Biomarker high-risk patients exhibited progressively worse renal function and decreased 5-year graft survival compared to low-risk patients. Treatment of B cells with anti-TNFα in vitro augmented the IL-10/TNFα ratio, restored regulatory activity, and inhibited plasmablast differentiation. To conclude, the T1B IL-10/TNFα ratio was validated as a strong predictive biomarker of renal allograft outcomes and provides a rationale for preemptive therapeutic intervention with TNF blockade.Chemoresistance remains the major challenge for successful treatment of acute myeloid leukemia (AML). Although recent mouse studies suggest that treatment response of genetically and immunophenotypically indistinguishable AML can be influenced by their different cells of origin, corresponding evidence in human disease is still largely lacking. By combining prospective disease modeling using highly purified human hematopoietic stem or progenitor cells with retrospective deconvolution study of leukemia stem cells (LSCs) from primary patient samples, we identified human hematopoietic stem cells (HSCs) and common myeloid progenitors (CMPs) as two distinctive origins of human AML driven by Mixed Lineage Leukemia (MLL) gene fusions (MLL-AML). selleck Despite LSCs from either MLL-rearranged HSCs or MLL-rearranged CMPs having a mature CD34-/lo/CD38+ immunophenotype in both a humanized mouse model and primary patient samples, the resulting AML cells exhibited contrasting responses to chemotherapy. HSC-derived MLL-AML was highly resistant to chemotherapy and expressed elevated amounts of the multispecific anion transporter ABCC3. Inhibition of ABCC3 by shRNA-mediated knockdown or with small-molecule inhibitor fidaxomicin, currently used for diarrhea associated with Clostridium difficile infection, effectively resensitized HSC-derived MLL-AML toward standard chemotherapeutic drugs. This study not only functionally established two distinctive origins of human LSCs for MLL-AML and their role in mediating chemoresistance but also identified a potential therapeutic avenue for stem cell-associated treatment resistance by repurposing a well-tolerated antidiarrhea drug already used in the clinic.Radiation proctopathy (RP) is characterized by inflammation of colorectal tissue and is a common complication of radiation therapy for pelvic malignancies with high incidence but lacking effective treatment. Here, we found that platelet-derived growth factor C (PDGF-C) and fibrosis markers were up-regulated in tissue samples from patients with RP and in rectal tissues after irradiation in a mouse model of RP. Genetic deletion of Pdgf-c in mice ameliorated RP-induced injuries. Genome-wide gene expression profiling and in vitro assays revealed that the promotive effect of PDGF-C in RP development was mediated by activation of PDGF receptors (PDGFRs) and C-X-C motif chemokine receptor 4, a proinflammatory chemokine regulated by transcription factor ETS variant transcription factor 1. Treatment with crenolanib, a selective inhibitor of PDGFRs, prevented or reduced RP in mice after irradiation. These results reveal that inhibition of PDGF-C signaling may have therapeutic value for the treatment of RP.Tumor-induced CD45-Ter119+CD71+ erythroid progenitor cells, termed "Ter cells," promote tumor progression by secreting artemin (ARTN), a neurotrophic peptide that activates REarranged during Transfection (RET) signaling. We demonstrate that both local tumor ionizing radiation (IR) and anti-programmed death ligand 1 (PD-L1) treatment decreased tumor-induced Ter cell abundance in the mouse spleen and ARTN secretion outside the irradiation field in an interferon- and CD8+ T cell-dependent manner. Recombinant erythropoietin promoted resistance to radiotherapy or anti-PD-L1 therapies by restoring Ter cell numbers and serum ARTN concentration. Blockade of ARTN or potential ARTN signaling partners, or depletion of Ter cells augmented the antitumor effects of both IR and anti-PD-L1 therapies in mice. Analysis of samples from patients who received radioimmunotherapy demonstrated that IR-mediated reduction of Ter cells, ARTN, and GFRα3, an ARTN signaling partner, were each associated with tumor regression. Patients with melanoma who received immunotherapy exhibited favorable outcomes associated with decreased expression of GFRα3. These findings demonstrate an out-of-field, or "abscopal," effect mediated by adaptive immunity, which is induced during local tumor irradiation. This effect, in turn, governs the therapeutic effects of radiation and immunotherapy. Therefore, our results identify multiple targets to potentially improve outcomes after radiotherapy and immunotherapy.Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disease without clear etiology or effective treatment. Genetic factors contribute to PSC pathogenesis, but so far, no causative mutation has been found. We performed whole-exome sequencing in a family with autosomal dominant inheritance of PSC and identified a heterozygous germline missense mutation in SEMA4D, encoding a K849T variant of CD100. The mutation was located in an evolutionarily conserved, unstructured cytosolic region of CD100 affecting downstream signaling. It was found to alter the function of CD100-expressing cells with a bias toward the T cell compartment that caused increased proliferation and impaired interferon-γ (IFN-γ) production after stimulation. Homologous mutation knock-in mice developed similar IFN-γ impairment in T cells and were more prone to develop severe cholangitis when exposed to 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet. Transfer of wild-type T cells to knock-in mice before and during DDC exposure attenuated cholangitis.