Citations

Neuroplastic changes in phrenic motor neurons that underlie recovery from spinal cord injury may be mediated by perineuronal nets. We show that changes in perineuronal nets around phrenic motor neurons occur within 7 days after cervical spinal cord injury, and that the increase in perineuronal nets around larger phrenic motor neurons was more pronounced. These changes are consistent with substantial reorganization of the neural network onto intact phrenic motor neurons following cervical spinal cord injury.

Brain-derived neurotrophic factor (BDNF) signals through its high-affinity full length tropomyosin receptor kinase-B (TrkB.FL). One key downstream target of BDNF/TrkB.FL signaling is phosphorylation of the transcription factor cyclic AMP response element-binding (CREB) protein at serine 133 (pCREBS133). We hypothesized that a positive feedback loop exists in the spinal cord in which BDNF/TrkB.FL induces pCREBS133 which then transcriptionally targets pro-BDNF expression. To test this hypothesis, we employed a loss of function approach using a novel chemogenetic rat model (TrkBF616A) with a knock-in allele sensitive to the selective kinase inhibitor 1NMPP1 to inhibit TrkB.FL kinase activity. In female and male TrkBF616A rats, we then examined the effects of 1NMPP1 (orally through drinking water) induced TrkB.FL kinase inhibition on BDNF levels in the cervical (CSC) and lumbar (LSC) spinal cord. The spinal cord was collected at two time points at 0700 and 010 reflecting the trough and peak timepoints of endogenous BDNF expression. BDNF levels were quantified using ELISA. We found in the CSC, BDNF levels did not vary across timepoints in either 1NMPP1 or vehicle treated groups. However, 1NMPP1-induced TrkB.FL inhibition significantly reduced BDNF levels at both timepoints (P=0.004). This reduction suggests that cervical circuits rely on continuous CREB-dependent support of BDNF expression and that inhibiting TrkB.FL disrupts this loop throughout the day. In the LSC, control rats displayed time of day-dependent variations in BDNF with lower levels at 0700 compared to 0100 (P=0.02). In contrast, 1NMPP1-induced inhibition of TrkB.FL reduced BDNF levels at 0100—when BDNF normally peaks in the LSC (P=0.01). This nighttime specific deficit supports the idea that activity-driven pCREBS133 activation is necessary to elevate BDNF during the active phase and that blocking TrkB.FL signaling disrupts this pCREBS133-mediated positive feedback. Overall, these results support a positive feedback that is region- and time-specific and involves BDNF/TrkB.FL signaling inducing pCREBS133 phosphorylation which then targets pro-BDNF expression in the spinal cord. Supported by NIH grants HL146114 and AG44615. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Abstract Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most common type of malignant lymphoma. Previous studies have shown that DLBCL cells are susceptible to GPX4 (Glutathione peroxidase 4)-regulated ferroptosis, an iron-dependent type of programmed cell death characterized by increased reactive oxygen species and excessive lipid peroxidation. In addition to GPX4, FSP1 (Ferroptosis suppressor protein 1, previously known as AIFM2) is a glutathione-independent repressor of ferroptosis that has shown prognostic significance in solid tumors. In this study, we aimed to reveal the significance of GPX4 and FSP1 in DLBCL. Patients and Methods: We performed immunohistochemistry (IHC) for GPX4 and FSP1 in a large cohorts of patients with de novo DLBCL, and evaluated their cytoplasmic and nuclear expression. Prognostic analysis was performed for FSP1 and GPX4 expression in patients treated with rituximab (R)-CHOP or CHOP chemotherapy, respective of TP53 mutation status, as p53 regulates ferroptosis and TP53 mutation is associated with poorer prognosis in DLBCL. Results: FSP1 expression with a ≥10% cutoff was positive in 42.3% of DLBCL cases. Patients with TP53 mutations had a non-significant trend of higher mean FSP1 expression than those with wild-type (Wt) TP53 (P=0.11). Prognostic analysis revealed that cytoplasmic FSP1+ expression was associated with significantly poorer overall survival and progression-free survival in Wt-TP53 DLBCLs treated with R-CHOP (P=0.016 and P=0.003, respectively), and only showed non-significant unfavorable trends in TP53 mutated DLBCLs and patients treated with CHOP. In contrast, GPX4 expression did not show a significant unfavorable prognostic effect in DLBCL, and in fact, was associated with a non-significant trend of better survival. Previously we have quantified immune cell abundance and PD-1/PD-L1 expression in the tumor microenvironment of the study cohort using multiplex fluorescent IHC. Correlative analysis found that FSP1+ patients had significantly higher mean and median abundance of CD68+ cells (both M1 and M2 macrophages) and CD11c+ cells than FSP1- patients. Further analysis in Wt-TP53 and mutated TP53 subcohorts found that only in the TP53 mutated DLBCL subcohort, FSP1 expression was associated with significantly higher mean and median CD163-CD68+ (M1) and overall CD68+ macrophages, whereas in the Wt-TP53 DLBCL subcohort, FSP1 expression was associated with significantly higher median (but not mean) CD163+CD68+ (M2) macrophages and CD11c+ cells. Summary: Cytoplasmic FSP1 expression but not GPX4 had significantly adverse prognostic effect in patients with Wt-TP53 DLBCL treated with standard immunochemotherapy. Our results also suggest that in addition to ferroptosis regulation, macrophage abundance was relevant for the prognostic effects of FSP1 expression. Citation Format: Beibei Lyu, Zijun Xu-Monette, Xiaoxian X. Zhao, Eric D. Hsi, Ming Chen, Carlo Visco, Alexandar Tzankov, Karen Dybkaer, Mu-En Wang, Chang Wang, Qingyan Au, Harry Nunns, Zenggang Pan, Benjamin Parsons, Santiago Montes-Moreno, Fenghuang Zhan, Michael B. Møller, Leon Bernal-Mizrachi, Youli Zu, Shanxiang Zhang, Weina Chen, Govind Bhagat, Yong Li, KEN H. YOUNG. Expression of the ferroptosis suppressor FSP1 but not GPX4 shows significant adverse prognostic effect in diffuse large B-cell lymphoma with wild-type TP53 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 4661.

Abstract Histones variant composition and post-translational modifications (PTMs) of core and linker histones jointly orchestrate chromatin architecture and tissue-specific gene regulation. However, capturing the full complexity of the “histone code” in native human tissues remains challenging. Here we present a human cardiac histone proteoform atlas—comprising intact histone variants with combinatorial PTMs—enabled by a streamlined top‑down proteomics workflow. In a single one‑dimensional reversed‑phase liquid chromatography (LC)-mass spectrometry (MS) run, we achieve baseline separation of all four core histone families (H2A, H2B, H3, and H4) together with the linker histone H1 directly from human myocardium. Notably, this intact-protein analysis preserves the connectivity of co-occurring PTMs to individual histone molecules to reveal the combinatorial histone code, enabling proteoform‑level quantification of histone‑variant composition and PTM stoichiometry at the chromatographic scale. Targeted MS/MS directly resolves co-occurring PTM combinations and distinguishes highly homologous histone isoforms. Using this approach, we assemble the first comprehensive cardiac histone proteoform atlas and uncover previously unobserved histone proteoforms. More broadly, this top-down proteomics workflow provides a robust framework for proteoform-resolved analysis of histone variants and PTMs in complex biological systems.

Abstract Background Icotrokinra is the first targeted oral peptide that selectively blocks the IL-23 receptor (IL-23R) and precisely inhibits the IL-23 pathway. In ANTHEM-UC—a Phase 2b, randomised, double-blind, placebo (PBO)-controlled, dose-ranging study in adults with moderately to severely active ulcerative colitis (UC)—all doses of icotrokinra achieved the primary endpoint of clinical response and delivered clinically meaningful improvements across key secondary endpoints at Week (W)12,1 which were maintained or improved at W28.2 Here we report the impact of icotrokinra on systemic and tissue biomarkers of inflammatory burden in UC. Methods Participants were randomised (1:1:1:1) to receive once-daily icotrokinra 100 mg, 200 mg, 400 mg, or PBO. Clinical inflammatory biomarkers, C-reactive protein (CRP) and faecal calprotectin (FCP), along with serum IL-23 pathway biomarkers (IL-22, IL-17A, and IL-17F) were used to determine the impact of icotrokinra on systemic inflammation. Gene expression changes in colonic biopsies were used to confirm tissue IL-23 pathway engagement and dampening of tissue inflammation with icotrokinra. Results At the W12 primary timepoint, all doses of icotrokinra attenuated levels of serum CRP and FCP (Figure 1). All doses of icotrokinra, but not PBO, markedly reduced serum levels of IL-22, IL-17A, and IL-17F at W12 relative to baseline. Greater reductions in these serum biomarkers of IL-23 pathway activation were observed with the 200 mg and 400 mg doses relative to the 100 mg dose (Figure 1, nominal p < 0.05). All doses of icotrokinra, but not PBO, markedly reduced expression of gene sets associated with the IL-23–driven inflammation in tissue at W12 relative to baseline (Figure 2, nominal p < 0.0001). With icotrokinra treatment, the tissue transcriptome more closely resembled that of healthy individuals, with decreased expression of gene sets associated with UC-relevant inflammatory cell types and increased expression of genes characteristic of healthy epithelial cells. Importantly, dampening of systemic and tissue inflammation with icotrokinra was sustained at W28 (Figures 1 & 2). Conclusion We show for the first time that blocking the IL-23R can inhibit IL-23-mediated inflammatory signaling in UC patients. Icotrokinra treatment induced a sustained (W28) reduction in systemic and tissue biomarkers of inflammatory burden in UC. Furthermore, icotrokinra induced transcriptional changes that are consistent with dampening of IL-23–driven inflammation and normalization of the tissue transcriptome. While all once-daily doses of icotrokinra attenuated systemic and tissue inflammation, greater reduction of systemic inflammatory burden was observed with the 200 mg and 400 mg doses of icotrokinra. References: 1. Abreu MT, et al. United European Gastroenterol J. 2025 10;13(suppl 8):172-3. 2. Jairath V, et al. Am J Gastroenterol. 2025 120;10(suppl 2):S312. Conflict of interest: Louis, Edouard: Education and Research Grants for my department: Abbvie, Takeda, Janssen, Pfizer, Fresenius-Kabi, Celltrion, EG pharma, Sandoz, Falk Personal Fees for conferences, advisory boards and consultancy: Abbvie, Takeda, Ferring, Pfizer, Janssen, Lilly, Galapagos, Celltrion, Arena, BMS, Falk, Biokuris, Fresenius-Kabi, Thabor Jairath, Vipul: Consulting fees from AbbVie, Alimentiv, Amgen, Anaptys Bio, Asahi Kasei, Asieris, Astra Zeneca, Attovia, Blackbird Labs, Bristol Myers Squibb, Boehringer Ingleheim, Biomebank, Caldera, Calluna, Catalytic Health, Celltrion, Ensho, Enthera, Exeliome Biosciences, Ferring, Fresenius Kabi, Gilead, Granite Bio, GSK, Johnson & Johnson, Lilly, Merck, Mountainfield, MRM Health, Nxera, Organon, OSE Immunotherapeutics, Pendopharm, Pioneering Medicine, Pfizer, Prometheus, Roche/Genentech, Sanofi, SCOPE, Shattuck Labs, Sorriso, Spyre, Synedgen, Takeda, Teva, Tillotts, Union Therapeutics, Ventus, Ventyx, Vividion, Xencor, Zealand Pharma. Siegmund, Britta: Consultant for AbbVie, Abivax, Boehringer Ingelheim, Bristol Myers Squibb, Dr. Falk Pharma, Eli Lilly, Endpoint Health, Galapagos, Johnson & Johnson, Materia Prima, MSD, Pfizer, Takeda, Wedbush Securities speaker for AbbVie, AlfaSigma, Bristol Myers Squibb, CED Service GmbH, Dr. Falk Pharma, Eli Lilly, Ferring, Galapagos, Johnson & Johnson, MD Education, MSD, Pfizer, Tr1xBio grant from Pfizer. Kannan, Arun K: Employee and shareholder of Johnson & Johnson Zeeman, Martha: Employee and shareholder of Johnson & Johnson Hart, Amy: Employee and shareholder of Johnson & Johnson Strawn, David: Employee and shareholder of Johnson & Johnson Venkat, Swati: Employee and shareholder of Johnson & Johnson Tomsho, Lynn: Employee and shareholder of Johnson & Johnson Mcrae, Bradford: Employee and shareholder of Johnson & Johnson Ruane, Darren: Employee and shareholder of Johnson & Johnson Surace, Lindsey: Employee and shareholder of Johnson & Johnson Erondu, Ngozi: Employee and shareholder of Johnson & Johnson Zhan, Joyce: Employee and shareholder of Johnson & Johnson Chen, Minhu: I have received speaker honoraria from Takeda China, Xian Janssen, and AbbVie China, as well as research funding from Takeda (China). Chachu, Karen: Advisory board for Johnson & Johnson consultant for OptumRx Matsuoka, Katsuyoshi: Grant: Abbvie Inc., Mochida Pharmaceutical Co., Ltd., ZERIA Pharmaceutical Co., Ltd., Nippon Kayaku Co., Ltd., JIMRO Co., Ltd. Personal Fees: Mitsubishi Tanabe Pharma, Janssen Pharmaceutical K.K., Abbvie Inc., EA Pharma Co., Ltd., Takeda Pharmaceutical Co., Ltd., Mochida Pharmaceutical Co., Ltd., ZERIA Pharmaceutical Co., Ltd., Nippon Kayaku Co., Ltd., Pfizer Inc., Kyorin Pharmaceutical Co., Ltd., Eli Lilly Japan K.K., Kissei Pharmaceutical Co., Ltd., Gilead Sciences, Celltrion Healthcare, Bristol-Myers Squibb Limdi, Jimmy: Speaker/consultancy fees from AbbVie, Abivax, Arena, BioHit, Bristol Myers Squibb, Celltrion, Eli Lilly, Ferring, Galapagos, Johnson & Johnson, MSD, Pfizer, Takeda research support from Galapagos, Takeda Rydzewska, Grazyna: Speaker and consultant fees from AbbVie, AlfaSigma, AstraZeneca, Bayer, Biocodex, Bristol Myers Squibb, Ferring, Johnson & Johnson, Lilly, PRO.MED.Pl, Recordati, Sanprobi, SOBI, Takeda travel/accommodation meeting expenses from AbbVie, Ferring, Takeda Abreu, Maria Teresa: Grant/Research Support: Janssen, Prometheus Bioscience, Takeda Consultant: Janssen, Prometheus Bioscience, Takeda Gilead, Eli Lilly, AbbVie Inc., Bristol Myers, Imedex, Loftus Jr, Edward V: Consultant/advisory board member for AbbVie, Amgen, Bristol Myers Squibb, Eli Lilly and Company, Genentech, Gilead Sciences, Johnson & Johnson, Pfizer, Takeda, UCB.

Abstract Pyroptosis is a form of programmed cell death characterized by the cleavage of the gasdermin (GSDM) family proteins that form pores in the plasma membrane, cell rupture, and the release of proinflammatory cytokines. In this study, we performed immunohistochemistry for cleaved gasdermin D (GSDMD), gasdermin E (GSDME) N-terminus, and gasdermin C (GSDMC) in 2 different cohorts of diffuse large B-cell lymphoma (DLBCL) and analyzed the impact of GSDM expression on prognosis and immunity. The results showed frequent cleaved GSDMD (N-terminal) expression. Only cytoplasmic GSDMD N-terminal expression correlated with significantly better patient survival in the 2 cohorts. In contrast, GSDME was mainly expressed in the vascular endothelium, and correlated with significantly adverse prognostic effect. Correlating with the multiplex fluorescent immunohistochemistry results, we found that cytoplasmic GSDMD N-terminal expression was associated with increased CD38+ (activated) M1 macrophages in both cohorts, cognate interactions between live DLBCL cells and activated M1 macrophages (and T cells), and lower PD-1/PD-L1 expression in the analyzed cases. In contrast, T-cell pyroptosis, lymphoma cell-resistance to cell death, and phagocytosis by M2 macrophages were observed in tissues with predominantly nuclear GSDMD N-terminal expression. Bulk gene expression profiling and deconvolution analysis revealed associations of cytoplasmic GSDMD N-terminal expression with downregulation of “Don’t eat me”–signaling genes, upregulation of many RNA genes, decreased frequency of “inflammatory” lymphoma microenvironment subtype, increased frequencies of prognostically favorable cell states and ecotypes, and decreased frequency of T-cell exhaustion state. In summary, this study showed distinct cellular and subcellular patterns of 3 GSDM proteins and their associated immune response phenotypes and prognostic effects, with implications for novel therapeutic strategies for B-cell lymphoma.

Abstract Background: Pyroptosis is a form of programmed cell death characterized by cleavage of gasdermin (GSDM) family proteins that form pores in the plasma membrane, cell rupture, and release of pro-inflammatory cytokines. Its pro-inflammatory potential has garnered significant research attention in recent years but has not been studied in lymphoma. Patients and Methods: We performed immunohistochemistry for cleaved GSDMD (n-terminal) in two large cohorts of diffuse large B-cell lymphoma (DLBCL) with multiplex fluorescent IHC (mfIHC) data, and analyzed for prognostic and immune impact. Results: Cleaved GSDMD was frequently expressed in DLBCL, and only the cytoplasmic (versus nuclear) form of expression correlated with significantly better patient survival in two DLBCL cohorts. To understand the expression at the single-cell level, we examined mfIHC results, which revealed that GSDMD+cells were tumor or immune cells, and varied in Ki-67, BCL2, and MYC expression. Cases with cytoplasmic cleaved GSDMD expression had higher mean and median levels of CD38+ (activated) M1 macrophages in two cohorts and lower PD-1/PD-L1 expression, as well as phenotypes of cognate interactions between live activated M1 macrophages, DLBCL cells, and T cells in spatially resolved immune landscape by mfIHC. In contrast, phagocytosis of pyroptotic lymphoma cells by M2 macrophages and cell death of T cells were observed in cases with predominantly nuclear form of cleaved GSDMD expression. Bulk gene expression profiling analysis identified a large proportion of RNA genes upregulated in DLBCLs with cytoplasmic cleaved GSDMD expression, and deconvolution analysis found decreased frequency of the “Inflammatory” lymphoma microenvironment (LME) subtype, increased frequency of cell states and ecotypes with favorable prognostic associations, and decreased frequency of T cell exhaustion states. Summary: Analysis of pyroptosis-inducing cleaved GSDMD (n-terminal) expression in a large number of DLBCL patients revealed dinstinctive cytoplasmic and nuclear expression patterns in live and pyroptotic cells associated with different prognostic and immune effects. Cytoplasmic cleaved GSDMD expression is a marker of cognate interactions between live cells (e.g., activated M1 macrophages) associated with adaptive responses and favorable prognostic effects, whereas nuclear cleaved GSDMD expression is associated with immunosuppressive mechanisms, including T cell death and phagocytosis by M2 macrophages.

Ischemic cardiomyopathy (ICM) is a leading cause of heart failure characterized by extensive remodeling of the cardiac extracellular matrix (ECM). While initially adaptive, ECM deposition following ischemic injury eventually turns maladaptive, promoting adverse cardiac remodeling. The strong link between the extent of fibrosis and adverse clinical outcomes has led to growing interest in ECM-targeted therapies to prevent or reverse maladaptive cardiac remodeling in ICM; yet, the precise composition of the ECM in ICM remains poorly defined. In this study, we employed sequential protein extraction enabled by the photocleavable surfactant Azo to enrich ECM proteins from left ventricular tissues of patients with end-stage ICM and nonfailing donor hearts. High-resolution mass spectrometry–based quantitative proteomics identified and quantified over 6,000 unique protein groups, including 315 ECM proteins. We discovered significant upregulation of key ECM components, particularly glycoproteins, proteoglycans, collagens, and ECM regulators. Notably, LOXL1 , FBLN1 , and VCAN were among the most differentially expressed. Functional enrichment analyses revealed enhanced TGFB signaling, integrin-mediated adhesion, and complement activation in ICM tissues, suggesting a feedback loop driving continued ECM deposition in the end-stage failing heart. Together, our findings provide a comprehensive proteomic landscape of ECM alterations in the end-stage ICM myocardium and identify promising molecular targets for therapeutic intervention.