Expression of VISTA regulated via IFN-γ governs endogenous T-cell function and exhibits correlation with the efficacy of CD19 CAR-T cell treated B-malignant mice.

BACKGROUND: Despite continuous improvements in the new target and construction of chimeric antigen receptor (CAR)-T, relapse remains a significant challenge following CAR-T therapy. Tumor microenvironment (TME) strongly correlates with the efficacy of CAR-T therapy. V-domain Ig suppressor of T-cell activation (VISTA), which exerts a multifaceted and controversial role in regulating the TME, acts not only as a ligand on antigen-presenting cells but also functions as a receptor on T cells. However, the characteristics and underlying mechanisms governing endogenous T-cell activation by VISTA, which are pivotal for reshaping the TME, remain incompletely elucidated. METHODS: The immunocompetent B acute lymphoblastic leukemia (B-ALL), lymphoma, and melanoma murine models were employed to investigate the characteristics of endogenous T cells within the TME following CD19 and hCAIX CAR-T cell therapy, respectively. Furthermore, we examined the role of VISTA controlled by interferon (IFN)-γ signaling in regulating endogenous T-cell activation and functionality in B-ALL mice. RESULTS: We demonstrated that the administration of CD19 CAR-T or hCAIX CAR-T cell therapy elicited augmented immune responses of endogenous T cells within the TME of B-ALL, lymphoma, and melanoma mice, thereby substantiating the efficacy of CAR-T cell efficacy. However, in the TME lacking IFN-γ signaling, VISTA levels remained elevated, resulting in attenuated cytotoxicity of endogenous T cells and reduced B-ALL recipient survival. Mice treated with CD19 CAR-T cells exhibited increased proportions of endogenous memory T cells during prolonged remission, which possessed the tumor-responsive capabilities to protect against B-ALL re-challenge. Compared with wild-type (WT) CAR-T treated mice, the administration of IFN-γ-/- CAR-T to both WT and IFN-γ-/- recipients resulted in a reduction in the numbers of endogenous CD4+ and CD8+ effectors, while exhibiting increased populations of naïve-like CD4+ T and memory CD8+ T cells. VISTA expression consistently remained elevated in resting or memory CD4+ T cells, with distinct localization from programmed cell death protein-1 (PD-1) expressing T subsets. Blocking the VISTA signal enhanced dendritic cell-induced proliferation and cytokine production by syngeneic T cells. CONCLUSION: Our findings confirm that endogenous T-cell activation and functionality are regulated by VISTA, which is associated with the therapeutic efficiency of CAR-T and provides a promising therapeutic strategy for relapse cases in CAR-T therapy.

[Prognostic Significance of Progression of Disease within 24 Months in Mantle Cell Lymphoma].

OBJECTIVE: To investigate the effect of progression of disease within 24 months (POD24) on overall survival (OS) in patients with mantle cell lymphoma (MCL), and compare the clinical characteristics between POD24 and non-POD24 patients. METHODS: A retrospective analysis was performed on 50 MCL patients with treatment indications and regular treatment who were admitted to the Affiliated Hospital of Xuzhou Medical University from January 2010 to August 2020. According to the occurrence of POD24, the patients were grouped for prognostic evaluation and clinical characteristics comparison. RESULTS: Univariate Cox regression analysis showed that POD24, PLT, albumin, MIPI score, ECOG PS score, LDH were the factors influencing OS in newly diagnosed MCL patients (all P < 0.05). The results of multivariate Cox regression analysis showed that POD24ï¼»HR=16.797(95%CI : 3.671-76.861),P < 0.001ï¼½, albumin<40 g/Lï¼»HR=3.238(95%CI :1.095-9.572),P =0.034ï¼½ and ECOG PS score≥2ï¼»HR=4.005(95%CI :1.033-15.521),P =0.045ï¼½ were independent risk factors influencing OS in MCL patients. The incidence of PLT<100×109/L (33.3% vs 5.9%, P =0.033) and ECOG PS score ≥2 (45.5% vs 5.9%, P =0.040) were significantly higher in POD24 patients than those in non-POD24 patients. CONCLUSION: POD24 is an independent poor prognostic factor affecting the OS of MCL patients, and the patients with PLT<100×109/L and ECOG PS score≥2 at diagnosis have a higher probability of POD24.

Short-term exposure to triclocarban alters microbial community composition and metabolite profiles in freshwater biofilms.

Triclocarban (TCC), an emerging contaminant in water environments, its effects on freshwater biofilms remain insufficiently understood. This study investigates the effects of TCC exposure (at concentrations of 10 µg L-1 and 10 mg L-1) on mature freshwater biofilms. TCC was found to inhibit biofilm activity as evidenced by changes in surface morphology and the ratio of live/dead cells. Moreover, both concentrations of TCC were observed to modify the structure of the biofilm community. Metabolomics analysis revealed an overlap in the toxicity mechanisms and detoxification strategies triggered by various concentrations of TCC in biofilms. However, the higher toxicity induced by 10 mg L-1 TCC resulted from the downregulation of proline betaine, disrupting the homeostasis of cellular osmotic pressure regulation in biofilms. Notably, lipid and lipid-like molecules showed high sensitivity to different concentrations of TCC, indicating their potential as biomarkers for TCC exposure. Annotation of the differential metabolites by KEGG revealed that alterations in amino acid and carbon metabolism constituted the primary response mechanisms of biofilms to TCC. Moreover, the biofilm demonstrated enhanced nucleic acid metabolism, which bolstered resistance against TCC stress and heightened tolerance. Furthermore, elevated TCC concentrations prompted more robust detoxification processes for self-defense. Overall, short-term exposure to TCC induced acute toxicity in biofilms, yet they managed to regulate their community structure and metabolic levels to uphold oxidative homeostasis and activity. This research contributes to a deeper comprehension of TCC risk assessment and policy control in aquatic environments.

Halting Multiple Myeloma with MALT1 Inhibition: Suppressing BCMA-Induced NF-κB and Inducing Immunogenic Cell Death.

As multiple myeloma (MM) poses a formidable therapeutic challenge despite recent progress, exploring novel targets is crucial. Mucosa-associated lymphoid tissue lymphoma translocation protein-1 (MALT1) emerges as a promising paracaspase with druggable potential, especially unexplored in MM. Our study provided compelling evidence demonstrating a statistically significant elevation of MALT1 expression in human primary MM cells. Moreover, elevated MALT1 expression was associated with a poorer prognosis in MM. Genetic deletion of MALT1 reduced cell growth, colony formation, and tumor growth in vivo. Pharmacological inhibition with 1 µM Mi-2 effectively inhibited cell growth, inducing mitochondria-dependent apoptotic cell death. Mechanistically, MALT1 inhibition disrupted diverse signal transduction pathways, notably impeding nuclear factor κB (NF-κB). Significantly, the inhibition of MALT1 demonstrated a substantial suppression of NF-κB activation by elevating IκB, disrupting the nuclear localization of p65 and c-Rel. This effect was observed in both the basal state and when stimulated by BCMA, highlighting the pivotal role of MALT1 inhibition in influencing MM cell survival. It was noteworthy that Mi-2 induces properties associated with immunogenic cell death (ICD), as evidenced by increased calreticulin (CRT), ATP release, and high-mobility group protein B1 (HMGB1) upregulation, consequently triggering ICD-associated immune activation and enhancing CD8+ T - cell cytotoxicity in vitro. In conclusion, our research highlights MALT1 as a promising druggable target for therapeutic interventions in MM, providing insights into its molecular mechanisms in MM progression.

Celastrus orbiculatus Extract Inhibits Immune Inflammatory Thrombotic State of B-Lymphoma.

OBJECTIVE: To investigate the inhibitory effect of Celastrus orbiculatus extracts (COE) on the proliferation of lymphoma cells and the immune regulation ability on inflammation and thrombophilia in vivo. METHODS: The 38B9 lymphoma cells were treated with COE (160 µ g/mL) and CTX (25 µ mol/L). The apoptosis rate and cell cycle of each group were detected by flow cytometry. The secretion of inflammatory factors, including interleukin (IL)-6, IL-10, and tumor necrosis factor α (TNF-α), in cell supernatant was detected by enzyme-linked immunosorbent assay (ELISA). In vivo, BALB/c mice were subcutaneously injected with 38B9 lymphoma cells to establish lymphoma model. COE (3 mg·kg-1·d-1) and CTX (40 mg·kg-1·d-1) were administered to the model mice, respectively. The expression of plasma inflammatory factors (IL-6, IL-10 and TNF-α) and thrombus indexes, including D-dimer (D-D), von Willebrand factor (vWF) and tissue factor (TF), were detected by ELISA before tumor bearing (1 d), after tumor formation (14 d) and after intervention (21 d). PicoGreen dsDNA was used to detect the level of serum neutrophil extracellular traps (NETs). Flow cytometry was used to detect the expression of platelet activation marker calcium-dependent lectin-like receptor 2 (CLEC-2). The tumor growth and survival of mice were recorded. RESULTS: The 38B9 lymphoma cells were apoptotic after the intervention of COE and CTX. The ratio of G2-M phase cells decreased in COE intervented cells compared with the control cells (P<0.05), and S phase cells decreased in CTX intervented cells (P<0.05). Also, the secretion level of IL-6 was significantly reduced after COE or CTX intervention (P<0.05), and IL-10 was significantly increased (P<0.05). Furthermore, the tumor mass was reduced, and the median survival time was longer in COE and CTX intervented tumor-bearing mice than in non-intervented mice. The significantly lower levels of TNF-α, IL-6, NETs, TF, DD and CLEC-2, as well as higher IL-10 were observed in COE and CTX treatment mice in comparision with the control mice (P<0.05). CONCLUSION: COE has a mild and stable anti-tumor effect, which can reduce the secretion of inflammatory factors by lymphoma cells and regulate thrombophilic state caused by tumor inflammatory microenvironment.

Notch1 regulates hepatic thrombopoietin production.

ABSTRACT: Notch signaling regulates cell-fate decisions in several developmental processes and cell functions. However, the role of Notch in hepatic thrombopoietin (TPO) production remains unclear. We noted thrombocytopenia in mice with hepatic Notch1 deficiency and so investigated TPO production and other features of platelets in these mice. We found that the liver ultrastructure and hepatocyte function were comparable between control and Notch1-deficient mice. However, the Notch1-deficient mice had significantly lower plasma TPO and hepatic TPO messenger RNA levels, concomitant with lower numbers of platelets and impaired megakaryocyte differentiation and maturation, which were rescued by addition of exogenous TPO. Additionally, JAK2/STAT3 phosphorylation was significantly inhibited in Notch1-deficient hepatocytes, consistent with the RNA-sequencing analysis. JAK2/STAT3 phosphorylation and TPO production was also impaired in cultured Notch1-deficient hepatocytes after treatment with desialylated platelets. Consistently, hepatocyte-specific Notch1 deletion inhibited JAK2/STAT3 phosphorylation and hepatic TPO production induced by administration of desialylated platelets in vivo. Interestingly, Notch1 deficiency downregulated the expression of HES5 but not HES1. Moreover, desialylated platelets promoted the binding of HES5 to JAK2/STAT3, leading to JAK2/STAT3 phosphorylation and pathway activation in hepatocytes. Hepatocyte Ashwell-Morell receptor (AMR), a heterodimer of asialoglycoprotein receptor 1 [ASGR1] and ASGR2, physically associates with Notch1, and inhibition of AMR impaired Notch1 signaling activation and hepatic TPO production. Furthermore, blockage of Delta-like 4 on desialylated platelets inhibited hepatocyte Notch1 activation and HES5 expression, JAK2/STAT3 phosphorylation, and subsequent TPO production. In conclusion, our study identifies a novel regulatory role of Notch1 in hepatic TPO production, indicating that it might be a target for modulating TPO level.

Associations of granulocyte colony-stimulating factor with toxicities and efficacy of chimeric antigen receptor T-cell therapy in relapsed or refractory B-cell acute lymphoblastic leukemia.

Few studies have reported the associations of granulocyte colony-stimulating factor (G-CSF) with cytokine release syndrome (CRS), neurotoxic events (NEs) and efficacy after chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We present a retrospective study of 67 patients with R/R B-ALL who received anti-CD19 CAR T-cell therapy, 41 (61.2%) patients received G-CSF (G-CSF group), while 26 (38.8%) did not (non-G-CSF group). Patients had similar duration of grade 3-4 neutropenia between the two groups. The incidences of CRS and NEs were higher in G-CSF group, while no differences in severity were found. Further stratified analysis showed that the incidence and severity of CRS were not associated with G-CSF administration in patients with low bone marrow (BM) tumor burden. None of the patients with low BM tumor burden developed NEs. However, there was a significant increase in the incidence of CRS after G-CSF administration in patients with high BM tumor burden. The duration of CRS in patients who used G-CSF was longer. There were no significant differences in response rates at 1 and 3 months after CAR T-cell infusion, as well as overall survival (OS) between the two groups. In conclusion, our results showed that G-CSF administration was not associated with the incidence or severity of CRS in patients with low BM tumor burden, but the incidence of CRS was higher after G-CSF administration in patients with high BM tumor burden. The duration of CRS was prolonged in G-CSF group. G-CSF administration was not associated with the efficacy of CAR T-cell therapy.

Bispecific CAR T cell therapy targeting BCMA and CD19 in relapsed/refractory multiple myeloma: a phase I/II trial.

Despite the high therapeutic response achieved with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapy in relapsed and refractory multiple myeloma (R/R MM), primary resistance and relapse exist with single-target immunotherapy. Here, we design bispecific BC19 CAR T cells targeting BCMA/CD19 and evaluate antimyeloma activity in vitro and in vivo. Preclinical results indicate that BC19 CAR specifically recognize target antigens, and BC19 CAR T cells mediate selective killing of BCMA or CD19-positive cancer cells. BC19 CAR T cells also exhibit potent antigen-specific anti-tumor activity in xenograft mouse models. We conduct an open-label, single-arm, phase I/II study of BC19 CAR T cells in 50 patients with R/R MM (ChiCTR2000033567). The primary endpoint was safety. BC19 CAR T cells are well tolerated with grade 3 or higher cytokine release syndrome in 8% of patients and grade 1 neurotoxic events in 4% of patients, which meet the pre-specified primary endpoint. Secondary endpoints include overall response rate (92%), median progression-free survival (19.7 months), median overall survival (19.7 months) and median duration of response (not reached). Our study demonstrates that bispecific BC19 CAR T cells are feasible, safe and effective in treating patients with R/R MM.

Loss of NLRP6 expression increases the severity of intestinal injury after syngeneic hematopoietic stem cell transplantation.

NLRP6 plays a crucial role in maintaining intestinal homeostasis by regulating the interaction between the intestinal mucosa and the microbiota. However, the impact of NLRP6 deficiency on intestinal damage following hematopoietic stem cell transplantation (HSCT) remains poorly understood. In this study, we established a syngeneic HSCT mouse model using C57BL/6 mice as donors and NLRP6-/- or C57BL/6 mice as recipients. Our findings revealed that NLRP6 deficiency had minimal influence on peripheral blood cell counts and splenic immune cell proportions in transplanted mice. However, it exacerbated pathological changes in the small intestine on day 14 post-transplantation, accompanied by increased proportions of macrophages, dendritic cells, and neutrophils. Furthermore, the NLRP6 deficiency resulted in elevated expression of MPO and CD11b, while reducing the levels mature caspase-1 and mature IL-1ß in the intestine. Moreover, the NLRP6 deficiency disturbed the expression of apoptosis-related molecules and decreased the tight junction protein occludin. Notably, recipient mice with NLRP6 deficiency exhibited lower mRNA expression levels of antimicrobial genes, such as Reg3γ and Pla2g2a. The short-term increase in inflammatory cell infiltration caused by NLRP6 deficiency was associated with intestinal damage, increased apoptosis, reduced expression of antimicrobial peptides, and impaired intestinal repair. Taken together, our findings demonstrate that the loss of NLRP6 exacerbates post-transplantation intestinal damage in recipient mice.

Complex association of body mass index and outcomes in patients with relapsed and refractory multiple myeloma treated with CAR-T cell immunotherapy.

BACKGROUND AIMS: Chimeric antigen receptor-T (CAR-T) cells have exhibited remarkable efficacy in treating refractory or relapsed multiple myeloma (R/R MM). Although obesity has a favorable value in enhancing the response to immunotherapy, less is known about its predictive value regarding the efficacy and prognosis of CAR-T cell immunotherapy. METHODS: We conducted a retrospective study of 111 patients with R/R MM who underwent CAR-T cell treatment. Using the body mass index (BMI) classification, the patients were divided into a normal-weight group (73/111) and an overweight group (38/111). We investigated the effect of BMI on CAR-T cell therapy outcomes in patients with R/R MM. RESULTS: The objective remission rates after CAR-T cell infusion were 94.7% and 89.0% in the overweight and normal-weight groups, respectively. The duration of response and overall survival were not significant difference between BMI groups. Compared to normal-weight patients, overweight patients had an improved median progression-free survival. There was no significant difference in cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome between the subgroups. In terms of hematological toxicity, the erythrocyte, hemoglobin, platelet, leukocyte and neutrophil recovery was accelerated in the overweight group. Fewer patients in the overweight group displayed moderate percent CD4 and CD4/CD8 ratios compared to the normal-weight group. Furthermore, the percent CD4 ratios were positively correlated with the levels of cytokines [interleukin-2 (IL-2) (day 14), interferon gamma (IFN-γ) (day 7) and tumor necrosis factor alpha (TNF-α) (days 14 and 21)] after cells infusion. On the other hand, BMI was positively associated with the levels of IFN-γ (day 7) and TNF-α (days 14 and 21) after CAR-T cells infusion. CONCLUSIONS: Overall, this study highlights the potential beneficial effect of a higher BMI on CAR-T cell therapy outcomes.

Impact of tocilizumab on anti-CD19 chimeric antigen receptor T-cell therapy in B-cell acute lymphoblastic leukemia.

BACKGROUND: Tocilizumab is commonly used for the management of chimeric antigen receptor (CAR) T-cell therapy-associated cytokine release syndrome (CRS). However, it remains unknown whether tocilizumab or its dosage affects the efficacy and safety of CAR T-cell therapy. The objective of this multicenter retrospective study was to explore the impact of tocilizumab on CAR T-cell therapy. METHODS: In total, 93 patients with B-cell acute lymphoblastic leukemia (B-ALL) receiving humanized anti-CD19 CAR T cells were recruited from May 2016 to November 2022. Forty-five patients received tocilizumab (tocilizumab group), whereas 48 patients did not (nontocilizumab group). Thirteen patients received >1 dose of tocilizumab. The primary end point was the effect of tocilizumab on the efficacy and safety of CAR T cells. Additionally, proliferation, killing, and cytokine assays of CAR T cells were performed in vitro in the presence of tocilizumab. RESULTS: The median age of the patients was 33 years, with 47 males and 46 females. Patients in the tocilizumab group showed similar complete response (CR) rate, overall survival (OS), and event-free survival (EFS) compared with the nontocilizumab group. Compared with patients who received ≤1 dose of tocilizumab, receiving >1 dose of tocilizumab did not affect their CR rate, OS, or EFS. In the tocilizumab group, all patients experienced CRS and 26.7% experienced immune effector cell-associated neurotoxicity syndrome (ICANS). In the nontocilizumab group, 64.6% of patients experienced CRS and 8.3% experienced ICANS. Up to 75% of ICANS and 87.5% of grade ≥3 ICANS occurred in the tocilizumab group. In vitro, tocilizumab did not impair the proliferation and killing effects of CAR T cells. CONCLUSIONS: Tocilizumab does not affect the efficacy of CAR T cells but may increase the likelihood of ICANS.

Thrombin receptor activating peptide-6 decreases acute graft-versus-host disease through activating GPR15.

G-protein coupled receptor 15 (GPR15) is expressed on T-cells. We previously reported knockout of GPR15 increased acute graft-versus-host disease (GvHD) in mice. In this study, we identified thrombin receptor activating peptide-6 (TRAP-6, peptide sequence: SFLLRN) as an activator of GPR15. GRP15 and ß-arrestin2 were needed for TRAP-6-mediated inhibition of mixed lymphocyte reactions. TRAP-6 decreased acute GvHD in allotransplant models in mice, an effect dependent on GPR15-expression in donor T-cells. RNA-seq and protein analyses indicated TRAP-6 increased binding of ß-arrestin2/TAB1 and inhibited phosphorylation of TAK1 and NF-κB-P65. GPR15 is expressed differently on CD4+ T-cells and CD8+ T-cells. TRAP-6 inhibited phosphorylation of NF-κB-P65 in CD4+ T-cells but increased granzyme B expression in CD8+ T-cells. TRAP-6 decreased acute GvHD without inhibiting graft-versus-tumor (GvT) efficacy against A20 lymphoma cells. SALLRN, a mutant of TRAP-6, preserved the anti-acute GvHD effect but avoided the adverse effects of TRAP-6. TRAP-6 and SALLRN also decreased allogeneic and xenogeneic reactions induced by human blood mononuclear cells. In conclusion, TRAP-6 activated GPR15 on T-cells and decreased acute GvHD in mice without impairing GvT efficacy.

Redox regulation of platelet function and thrombosis.

Platelets are well-known players in several cardiovascular diseases such as atherosclerosis and venous thrombosis. There is increasing evidence demonstrating that reactive oxygen species (ROS) are generated within activated platelets. Nicotinamide adenine dinucleotide phosphate oxidase (NOX) is a major source of ROS generation in platelets. Ligand binding to platelet receptor glycoprotein (GP) VI stimulates intracellular ROS generation consisting of a spleen tyrosine kinase-independent production involving NOX activation and a following spleen tyrosine kinase-dependent generation. In addition to GPVI, stimulation of platelet thrombin receptors (protease-activated receptors [PARs]) can also trigger NOX-derived ROS production. Our recent study found that mitochondria-derived ROS production can be induced by engagement of thrombin receptors but not by GPVI, indicating that mitochondria are another source of PAR-dependent ROS generation apart from NOX. However, mitochondria are not involved in GPVI-dependent ROS generation. Once generated, the intracellular ROS are also involved in modulating platelet function and thrombus formation; therefore, the site-specific targeting of ROS production or clearance of excess ROS within platelets is a potential intervention and treatment option for thrombotic events. In this review, we will summarize the signaling pathways involving regulation of platelet ROS production and their role in platelet function and thrombosis, with a focus on GPVI- and PAR-dependent platelet responses.

Macrophage depletion damages hematopoiesis partially through inhibition of cell homing and expansion after hematopoietic cell transplantation.

Bone marrow macrophages (Mφ) are essential components of the bone marrow niche that regulate the function of hematopoietic stem cells. Poor graft function and inhibition of hematopoietic production can result from abnormal macrophage function; however, the underlying mechanism is unclear. Clodronate liposomes (Clo-Lip) have been used widely to deplete macrophages and study their functions. Our previous results showed that Clod-Lip-mediated clearance of macrophages plays a vital role in regulating hematopoietic reconstruction after allogeneic hematopoietic cell transplantation (HCT). In this study, using an isogenic hematopoietic stem cell transplantation model, we found that Clod-Lip-mediated clearance of macrophages suppressed hematopoietic reconstruction by inhibiting the homing process of hematopoietic cells. We also demonstrated that macrophage depletion inhibited the direct supportive effect of macrophages on hematopoietic stem and progenitor cells and erythroid differentiation but promoted the production of megakaryocytic progenitors ex vivo. We showed that macrophages increase CD49e expression on hematopoietic stem and progenitor cells (HSPCs). However, CD49e inhibitors did not support the proliferative effect of macrophages on hematopoietic cells. In contrast, macrophage E-selectin/ intercellular cell adhesion molecule-1 (ICAM-1) may be involved in directly regulating HSPCs. In conclusion, macrophage depletion with Clo-Lip partially disrupts bone marrow hematopoiesis after HCT by impeding donor cell homing and macrophage-HSPCs interactions.

Multi-centers experience using therapeutic plasma exchange for corticosteroid/tocilizumab-refractory cytokine release syndrome following CAR-T therapy.

The chimeric antigen receptor T (CAR-T) cell therapy significantly enhances the prognosis of various hematologic malignancies; however, the systemic expansion of CAR-T cells also gives rise to severe cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). Despite the successful application of corticosteroids and tocilizumab in alleviating severe CRS in most patients, there are still individuals who experience life-threatening CRS without responding to the aforementioned therapies. In our retrospective cohort, we conducted an analysis of clinical and laboratory parameters, including inflammatory cytokines, in 17 patients from three centers who underwent therapeutic plasma exchange (TPE) for refractory CRS with or without ICANS following CAR-T products treatment. Our findings demonstrate a significant improvement in both clinical symptoms and laboratory parameters subsequent to TPE treatment. The rapid decrease in temperature and levels of inflammatory indexes indicates the remarkable scavenging efficacy of TPE against cytokine storm following CAR-T therapy. In conclusion, TPE may serve as a valuable and safe adjunct to corticosteroids and tocilizumab in the management of severe CRS resulting from CAR-T cell infusion. We eagerly await further prospective studies to validate this finding.

Endothelial Robo4 suppresses endothelial-to-mesenchymal transition induced by irradiation and improves hematopoietic reconstitution.

Bone marrow ablation is routinely performed before hematopoietic stem cell transplantation (HSCT). Hematopoietic stem and progenitor cells (HSPCs) require a stable bone marrow microenvironment to expand and refill the peripheral blood cell pool after ablation. Roundabout guidance receptor 4 (Robo4) is a transmembrane protein exclusive to endothelial cells and is vital in preserving vascular integrity. Hence, the hypothesis is that Robo4 maintains the integrity of bone marrow endothelial cells following radiotherapy. We created an endothelial cell injury model with γ-radiation before Robo4 gene manipulation using lentiviral-mediated RNAi and gene overexpression techniques. We demonstrate that Robo4 and specific mesenchymal proteins (Fibronectin, Vimentin, αSma, and S100A4) are upregulated in endothelial cells exposed to irradiation (IR). We found that Robo4 depletion increases the expression of endoglin (CD105), an auxiliary receptor for the transforming growth factor (TGF-ß) family of proteins, and promotes endothelial-to-mesenchymal transition (End-MT) through activation of both the canonical (Smad) and non-canonical (AKT/NF-κB) signaling pathways to facilitate Snail1 activation and its nuclear translocation. Endothelial Robo4 overexpression stimulates the expression of immunoglobulin-like adhesion molecules (ICAM-1 and VCAM-1) and alleviates irradiation-induced End-MT. Our coculture model showed that transcriptional downregulation of endothelial Robo4 reduces HSPC proliferation and increases HSC quiescence and apoptosis. However, Robo4 overexpression mitigated the damaged endothelium's suppressive effects on HSC proliferation and differentiation. These findings indicate that by controlling End-MT, Robo4 preserves microvascular integrity after radiation preconditioning, protects endothelial function, and lessens the inhibitory effect of damaged endothelium on hematopoietic reconstitution.

The prognostic significance of POD24 in peripheral T-cell lymphoma.

BACKGROUND: Peripheral T-cell lymphomas (PTCL) are an aggressive group of mature T-cell neoplasms, often associated with poor outcomes, in part, due to frequent relapsed/refractory disease. The objective of this study was to assess the prognostic impact of disease progression within 24 months (POD24) on overall survival (OS) for patients diagnosed with PTCL. METHODS: A retrospective analysis was conducted on a cohort of patients with newly diagnosed PTCL who underwent chemotherapy at the Affiliated Hospital of Xuzhou Medical University between January 2010 and September 2021. Prognostic assessment was limited to patients who were evaluable for POD24. RESULTS: Records were reviewed for 106 patients with PTCL, of whom 66 patients experienced POD24 (referred to as the POD24 group) and 40 patients did not experience POD24 (referred to as the no POD24 group). Significant differences were observed between the POD24 group and the no POD24 group in regard to clinical stage, Eastern Cooperative Oncology Group (ECOG) performance status (PS), International Prognostic Index (IPI) score, lactate dehydrogenase (LDH) levels, ß2-microglobulin (ß2-MG) levels, prealbumin and albumin levels. Patients in the POD24 group had a significant shorter median OS compared to the no POD24 group (11.9 months vs not reached, respectively; P < 0.001). Non response (NR) to treatment and POD24 were identified as independent negative prognostic factors for survival in patients with PTCL. CONCLUSION: POD24 is a prognostic factor associated with unfavorable outcomes in patients with PTCL and can be used to identify high-risk patients and guide treatment decisions.

A novel 2-iminobenzimidazole compound, XYA1353, displays in vitro and in vivo anti-myeloma activity via targeting NF-κB signaling.

Multiple myeloma (MM) is an accumulated disease of malignant plasma cells, which is still incurably owing to therapeutic resistance and disease relapse. Herein, we synthesized a novel 2-iminobenzimidazole compound, XYA1353, showing a potent anti-myeloma activity both in vitro and in vivo. Compound XYA1353 dose-dependently promoted MM cell apoptosis via activating caspase-dependent endogenous pathways. Moreover, compound XYA1353 could enhance bortezomib (BTZ)-mediated DNA damage via elevating γH2AX expression levels. Notably, compound XYA1353 interacted synergistically with BTZ and overcame drug resistance. RNA sequencing analysis and experiments confirmed that compound XYA1353 inhibited primary tumor growth and myeloma distal infiltration by disturbing canonical NF-κB signaling pathway via decreasing expression of P65/P50 and p-IκBα phosphorylation level. Due to its importance in regulating MM progression, compound XYA1353 alone or combined with BTZ may potentially exert therapeutic effects on multiple myeloma by suppressing canonical NF-κB signaling.