�����ƽ��

Inflammatory pain results from the heightened sensitivity and reduced threshold of nociceptor sensory neurons due to exposure to inflammatory mediators. However, the cellular and transcriptional diversity of immune cell and sensory neuron types makes it challenging to decipher the immune mechanisms underlying pain. Here we used single-cell transcriptomics to determine the immune gene signatures associated with pain development in three skin inflammatory pain models in mice: zymosan injection, skin incision and ultraviolet burn. We found that macrophage and neutrophil recruitment closely mirrored the kinetics of pain development and identified cell-type-specific transcriptional programs associated with pain and its resolution. Using a comprehensive list of potential interactions mediated by receptors, ligands, ion channels and metabolites to generate injury-specific neuroimmune interactomes, we also uncovered that thrombospondin-1 upregulated by immune cells upon injury inhibited nociceptor sensitization. This study lays the groundwork for identifying the neuroimmune axes that modulate pain in diverse disease contexts. Subject terms: Neuroimmunology, Inflammation

Interference with microtubule dynamics in mitosis activates the spindle assembly checkpoint (SAC) to prevent chromosome segregation errors. The SAC induces mitotic arrest by inhibiting the anaphase-promoting complex (APC) via the mitotic checkpoint complex (MCC). The MCC component MAD2 neutralizes the critical APC cofactor, CDC20, preventing exit from mitosis. Extended mitotic arrest can promote mitochondrial apoptosis and caspase activation. However, the impact of mitotic cell death on tissue homeostasis in vivo is ill-defined. By conditional MAD2 overexpression, we observe that chronic SAC activation triggers bone marrow aplasia and intestinal atrophy in mice. While myelosuppression can be compensated for, gastrointestinal atrophy is detrimental. Remarkably, deletion of pro-apoptotic Bim/Bcl2l11 prevents gastrointestinal syndrome, while neither loss of Noxa/Pmaip or co-deletion of Bid and Puma/Bbc3 has such a protective effect, identifying BIM as rate-limiting apoptosis effector in mitotic cell death of the gastrointestinal epithelium. In contrast, only overexpression of anti-apoptotic BCL2, but none of the BH3-only protein deficiencies mentioned above, can mitigate myelosuppression. Our findings highlight tissue and cell-type-specific survival dependencies in response to SAC perturbation in vivo.

Of all gynecologic cancers, epithelial-ovarian cancer (OCa) stands out with the highest mortality rates. Despite all efforts, 90% of individuals who receive standard surgical and cytotoxic therapy experience disease recurrence. The precise mechanism by which leukemia inhibitory factor (LIF) and its receptor (LIFR) contribute to the progression of OCa remains unknown. Analysis of cancer databases revealed that elevated expression of LIF or LIFR was associated with poor progression-free survival of OCa patients and a predictor of poor response to chemotherapy. Using multiple primary and established OCa cell lines or tissues that represent five subtypes of epithelial-OCa, we demonstrated that LIF/LIFR autocrine signaling is active in OCa. Moreover, treatment with LIFR inhibitor, EC359 significantly reduced OCa cell viability and cell survival with an IC 50 ranging from 5-50 nM. Furthermore, EC359 diminished the stemness of OCa cells. Mechanistic studies using RNA-seq and rescue experiments unveiled that EC359 primarily induced ferroptosis by suppressing the glutathione antioxidant defense system. Using multiple in vitro, ex vivo and in vivo models including cell-based xenografts, patient-derived explants, organoids, and xenograft tumors, we demonstrated that EC359 dramatically reduced the growth and progression of OCa. Additionally, EC359 therapy considerably improved tumor immunogenicity by robust CD45 + leukocyte tumor infiltration and polarizing tumor-associated macrophages (TAMs) toward M1 phenotype while showing no impact on normal T-, B-, and other immune cells. Collectively, our findings indicate that the LIF/LIFR autocrine loop plays an essential role in OCa progression and that EC359 could be a promising therapeutic agent for OCa. Subject terms: Molecular medicine, Ovarian cancer

The development of tyrosine kinase inhibitors (TKIs) has revolutionarily increased the overall survival of patients with chronic myeloid leukemia (CML). However, drug resistance remains a major obstacle. Here, we demonstrated that a BCR-ABL1-independent long non-coding RNA, IRAIN , is constitutively expressed at low levels in CML, resulting in imatinib resistance. IRAIN knockdown decreased the sensitivity of CD34 + CML blasts and cell lines to imatinib, whereas IRAIN overexpression significantly increased sensitivity. Mechanistically, IRAIN downregulates CD44, a membrane receptor favorably affecting TKI resistance, by binding to the nuclear factor kappa B subunit p65 to reduce the expression of p65 and phosphorylated p65. Therefore, the demethylating drug decitabine, which upregulates IRAIN , combined with imatinib, formed a dual therapy strategy which can be applied to CML with resistance to TKIs. Subject areas: Molecular biology, Cell biology, Cancer

Differentiation of human pluripotent stem cells (hPSCs) into subtype-specific neurons holds substantial potential for disease modeling in vitro . For successful differentiation, a detailed understanding of the transcriptional networks regulating cell fate decisions is critical. The heterochronic nature of neurodevelopment, during which distinct cells in the brain and during in vitro differentiation acquire their fates in an unsynchronized manner, hinders pooled transcriptional comparisons. One approach is to “translate” chronologic time into linear developmental and maturational time. Simple binary promotor-driven fluorescent proteins (FPs) to pool similar cells are unable to achieve this goal, due to asynchronous promotor onset in individual cells. We tested five fluorescent timer (FT) molecules expressed from the endogenous paired box 6 (PAX6) promoter in 293T and human hPSCs. Each of these FT systems faithfully reported chronologic time in 293T cells, but none of the FT constructs followed the same fluorescence kinetics in human neural progenitor cells. Subject areas: Natural sciences, Biological sciences, Biochemistry, Molecular biology, Neuroscience, Cellular neuroscience, Cell biology

Establishing robust models of human myelinating Schwann cells is critical for studying peripheral nerve injury and disease. Stem cell differentiation has emerged as a key human cell model and disease motivating development of Schwann cell differentiation protocols. Human embryonic stem cells (hESCs) are considered the ideal pluripotent cell but ethical concerns regarding their use have propelled the popularity of human induced pluripotent stem cells (hiPSCs). Given that the equivalence of hESCs and hiPSCs remains controversial, we sought to compare the molecular and functional equivalence of hESC- and hiPSC-derived Schwann cells generated with our previously reported protocol. We identified only modest transcriptome differences by RNA sequencing and insignificant proteome differences by antibody array. Additionally, both cell types comparably improved nerve regeneration and function in a chronic denervation and regeneration animal model. Our findings demonstrate that Schwann cells derived from hESCs and hiPSCs with our protocol are molecularly comparable and functionally equivalent. Subject areas: Neuroscience, Cell biology, Stem cells research, Transcriptomics