Atrophy Of Spleen Research Articles

Pathogenesis of Experimental Infection of Nile Tilapia (Oreochromis niloticus) with Nucleospora Braziliensis Pathology and Proteomic of Microsporidia.

The recent discovery of disease caused by Nucleospora braziliensis in Nile tilapia (Oreochromis niloticus) is important as it has highlighted the high prevalence of infection and associated mortality in cultured fish. Thus, this study conducted an experimental infection of this microsporidium to evaluate pathological alterations and conduct proteomic analysis. For pathological observation, samples of brain, eyes, gall bladder, gut, heart, kidney, liver, muscle, skin, spleen, and stomach tissue, were collected, and liquid chromatography-mass spectrometry (LC-MS/MS) was performed for proteomic analysis. The most prevalent lesions were brownish color of the liver, gill filament fusion, gut ischemia, hemorrhage of the lips and fins, hepatomegaly, spleen atrophy, splenomegaly, and stomach congestion. The most common microscopic lesions were degeneration, hemorrhage, and inflammation in the brain, gills, gut, kidney, liver, muscle, spleen, and stomach. The digested peptides were identified by LC-MS/MS and the intersection of each group showed that in the spleen there were 121 exclusive proteins in the infected sample and 252 in the control, while in the kidney, 129 proteins were identified in the infected specimen compared to 83 in the control. In conclusion, this study demonstrates the proteome profile of O. niloticus kidney and spleen tissue in response to infection with N. braziliensis.

Spinal Cord Injury Enhances Lung Inflammation and Exacerbates Immune Response After Acute Lung Injury.

The severity of spinal cord injury (SCI) is closely tied to pulmonary function, especially in cases of higher SCI levels. Despite this connection, the underlying pathological mechanisms in the lungs post-SCI are not well understood. Previous research has established a connection between disrupted sympathetic regulation and splenocyte apoptosis in high thoracic SCI, leading to pulmonary dysfunction. The aim of this study was to investigate whether mice with low-level SCI exhibit increased susceptibility to acute lung injury by eliciting systemic inflammatory responses that operate independently of the sympathetic nervous system. Here, we employed T9 contusion SCI and exposed mice to aerosolized lipopolysaccharide (LPS) to simulate lung inflammation associated with acute respiratory distress syndrome (ARDS). Twenty-four hours post-LPS exposure, lung tissues and bronchoalveolar lavage (BAL) fluid were analyzed. LPS markedly induced proinflammatory gene expression (SAA3, IRG1, NLRP3, IL-1beta, MCP-1) and cytokine release (IL-1beta, IL-6, MCP-1) in SCI mice compared to controls, indicating an exaggerated inflammatory response. Infiltration of Ly6G/C positive neutrophils and macrophages was significantly higher in SCI mice lungs post-LPS exposure. Interestingly, spleen size and weight did not differ between control and SCI mice, suggesting that T9 SCI alone does not cause spleen atrophy. Notably, bone-marrow-derived macrophages (BMDMs) from SCI mice exhibited hyper-responsiveness to LPS. This study demonstrated an increase in lung inflammation and immune responses subsequent to low-level T9 SCI, underscoring the widespread influence of systemic inflammation post-SCI, especially pronounced in specific organs like the lungs.

Buyang huanwu decoction alleviates stroke-induced immunosuppression in MCAO mice by reducing splenic T cell apoptosis triggered by AIM2 inflammasome

Ethnopharmacological relevanceIschemic stroke is a serious disabling and fatal disease that places a heavy burden on the world. Stroke induces a state of systemic immunosuppression that is strongly associated with an increased risk of infection and severe outcomes. Buyang Huanwu Decoction (BYHWD) is an ancient Chinese traditional formula with a good clinical and experimental basis. However, the role of BYHWD on post-stroke immunomodulation, especially immunosuppression, is unclear. Aim of the studyThe aim of this study was to investigate the pharmacological mechanism of BYHWD to alleviate ischemic stroke by analyzing splenic T cells apoptosis triggered by the AIM2 inflammasome activation cascade. Materials and methodsAn ischemic stroke model in C57BL/6 J mice was constructed using the MCAO method. The mNSS test and the hanging wire test were conducted to evaluate neurological impairment in mice. Histopathological damage was visualized by Nissl staining and HE staining. The protective effects of BYHWD on the spleen were determined by splenic index and spleen HE staining. The inhibition of AIM2 inflammasome cascade by BYHWD were explored through immunofluorescence (IF), flow cytometry, enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Flow cytometry was used to assess the apoptosis of splenic T cells. ResultsBYHWD significantly reduced infarct size, improved neurological function scores, and alleviated histopathological damage in middle cerebral artery occlusion (MCAO) mice. At the same time, BYHWD salvaged spleen atrophy. BYHWD significantly ameliorated apoptosis of splenic T lymphocytes. Key proteins and factors in the AIM2/IL-1β/FasL/Fas axis are effectively inhibited from expression after BYHWD treatment. ConclusionIt is the first study to demonstrate that BYHWD can improve stroke-induced immunosuppression by down-regulating Fas-dependent splenic T-cell apoptosis triggered by peripheral AIM2 inflammasome-driven signaling cascade.

Comparing the pharmacological effects of the prepared folium of Epimedium brevicornu Maxim. and Epimedium sagittatum Maxim. on kidney-Yang deficiency syndrome and liver injury complications

Yinyanghuo, a famous herb, includes the folium of Epimedium brevicornu Maxim. and Epimedium sagittatum Maxim. It is believed that their processed products, the prepared slices of the folium of Epimedium brevicornu Maxim. (PFEB) and Epimedium sagittatum Maxim. (PFES) have greater efficacy in tonifying kidney Yang to treat kidney-Yang deficiency syndrome (KDS). However, there are few studies comparing the pharmacological effects of PFEB and PFES, and the underlying mechanisms. This study compared their effects on improving hypothalamic-pituitary-adrenal (HPA) axis, immune system and sexual characteristic, as well as repairing liver injury complications in the KDS model mice. Additionally, the mechanisms of the effects relevance to their main components were explored. It was found that PFEB was more effective than PFES in increasing cAMP/cGMP ratio, SOD activity, CRH and ACTH levels, eNOS and testosterone levels, splenic lymphocytes proliferation, while in decreasing MDA content, atrophy of spleen and thymus, splenic lymphocytes apoptosis, and PDE5 level. PFES showed stronger protection than PFEB in decreasing triglyceride and hepatic lipid. The contents of baohuoside I and epimedin A, B were much higher in PFEB, while Epimedin C, Icariin, 2-O″-rhamnosylicaridide II were higher in PFES. Consequently, PFEB exhibits superior efficacy over PFES in tonifying the kidney-Yang by improving the neuroendocrine-immune network, including HPA axis, immune systems, and corpus cavernosum. However, PFES has better recovery effect on mild hepatic lipid caused by KDS. The efficacy difference between PFEB and PFES in kidney-Yang and liver may be attributed to the content variations of baohuoside I.

Intravenous Reelin rescues despair-like behavior, Reelin cells in the dentate sub-granular zone, and spleen atrophy in the cyclic corticosterone model of recurring depressive episodes.

Novel antidepressants are predominantly evaluated preclinically in rodent models of chronic stress in which animals experience a single prolonged exposure to chronic stress prior to treatment. Rodent models of a single episode of chronic stress translate poorly to human depressive disorders, which are commonly marked by recurring depressive episodes. Intravenous administration of Reelin has previously been shown to resolve immobility in the forced swim test of rats exposed to a single prolonged exposure to chronic stress. To determine whether Reelin has antidepressant-like properties in a model of recurring depressive episodes, Long-Evans rats (N = 57) were exposed to multiple cycles of chronic stress and stress-free periods before the administration of a single injection of Reelin during the final cycle of chronic stress. The animals then performed in the forced swim test and open field test before the post-mortem evaluation of Reelin cell counts in the sub-granular zone of the dentate gyrus to determine the impact of treatment on hippocampal Reelin levels and spleen white pulp to evaluate the role of Reelin treatment in peripheral inflammation. The results show a single Reelin injection reversed elevated levels of immobility in the forced swim test in both male and female subjects exposed to the cyclic chronic stress model of recurring depressive episodes. Treatment with Reelin also restored Reelin-positive cell counts in the dentate gyrus sub-granular zone and reversed atrophy of spleen white pulp. The results shown here indicate that treatment with Reelin could effectively resolve alterations in forced swim test behavior caused by the cyclic corticosterone model of recurring depressive episodes and that Reelin homeostasis is important for regulating stress-related inflammation. Future preclinical antidepressant research should incorporate models of multiple depressive episodes to improve the translation of preclinical rodent research to human depressive disorders.

Therapeutic effect of notoginseng saponins before and after fermentation on blood deficiency rats.

Notoginseng saponins (NS) are the active ingredients in Panax notoginseng (Burk.) F.H. Chen (PN). NS can be transformed depending on how the extract is processed. Fermentation has been shown to produce secondary ginsenosides with increased bioavailability. However, the therapeutic effect of fermented NS (FNS) requires further study. The present study compared the compositions and activities of FNS and NS in blood deficiency rats, which resembles the symptoms of anemia in modern medicine, induced by acetylphenylhydrazine and cyclophosphamide. A total of 32 rats were randomly divided into control, model, FNS and NS groups. A blood deficiency model was established and then treatment was orally administered for 21 days. The results of component analysis indicated that some saponins transformed during the fermentation process resulting in a decrease of notoginsenoside R1, and ginsenosides Rg1, Rb1 and Re, and an increase in ginsenosides Rd, Rh2, compound K, protopanaxadiol and protopanaxatriol. The animal results showed that both FNS and NS increased the number of white blood cells (WBCs), red blood cells, hemoglobin, platelets and reticulocytes, and the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), erythropoietin (EPO) and thrombopoietin (TPO), decreased the G0/G1 phase and increased G2/M phase, and decreased the apoptosis rate of bone marrow (BM) cells, which suggested a contribution to the recovery of hematopoietic function of the BM cells. FNS and NS increased the protein expression levels of the cytokines IL-4, IL-10, IL-12, IL-13, TGF-β, IL-6, IFN-γ and TNF-α, and the mRNA expression levels of transcription factors GATA binding protein 3 and T-box expressed in T cell (T-bet). FNS and NS treatment also increased the number of CD4+ T cells, and decreased the enlargement of the rat spleen and thymus atrophy, which indicated a protective effect on the organs of the immune system. The results of the present study demonstrated that compared with NS, FNS showed an improved ability to increase the levels of WBCs, lymphocytes, GM-CSF, EPO, TPO, aspartate aminotransferase, IL-10, IL-12, IL-13 and TNF-α, and the mRNA expression levels of T-bet, and decrease alanine aminotransferase levels. The differences seen for FNS treatment could arise from their improved bioavailability compared with NS, due to the larger proportion of hydrophobic ginsenosides produced during fermentation.

Comparative analyses of Netherton syndrome patients and Spink5 conditional knock-out mice uncover disease-relevant pathways

Netherton syndrome (NS) is a rare skin disease caused by loss-of-function mutations in the serine peptidase inhibitor Kazal type 5 (SPINK5) gene. Disease severity and the lack of efficacious treatments call for a better understanding of NS mechanisms. Here we describe a novel and viable, Spink5 conditional knock-out (cKO) mouse model, allowing to study NS progression. By combining transcriptomics and proteomics, we determine a disease molecular profile common to mouse models and NS patients. Spink5 cKO mice and NS patients share skin barrier and inflammation signatures defined by up-regulation and increased activity of proteases, IL-17, IL-36, and IL-20 family cytokine signaling. Systemic inflammation in Spink5 cKO mice correlates with disease severity and is associated with thymic atrophy and enlargement of lymph nodes and spleen. This systemic inflammation phenotype is marked by neutrophils and IL-17/IL-22 signaling, does not involve primary T cell immunodeficiency and is independent of bacterial infection. By comparing skin transcriptomes and proteomes, we uncover several putative substrates of tissue kallikrein-related proteases (KLKs), demonstrating that KLKs can proteolytically regulate IL-36 pro-inflammatory cytokines. Our study thus provides a conserved molecular framework for NS and reveals a KLK/IL-36 signaling axis, adding new insights into the disease mechanisms and therapeutic targets.

Changes in splenic tissue and immune response profile of Schistosoma mansoni infected mice submitted to chronic ethanol intake.

In Schistosoma mansoni infection, the spleen is one of the organs affected, causing its enlargement (splenomegaly). Intake of ethanol through alcoholic beverages can cause spleen atrophy and interfere with immune activity. To gain knowledge of this association on the spleen and on the immune response profile, male mice were used as an experimental model. These animals were divided into four groups: C. control; EC. uninfected/ethanol gavage; I. infected; and IE. infected/ethanol gavage. Groups I and IE were infected with about 100 cercariae (BH strain) of S. mansoni and in the fifth week of infection, gavage 200 μL/day/animal of 18 % ethanol was started for 28 consecutive days. At the end of the gavage (9th week of infection) all animals were euthanized. The spleen was removed and longitudinally divided in two parts. After histological processing, the sections were stained with H&E and Gomori's Reticulin for histopathological and stereological analyses, white pulp morphometry and quantification of megakaryocytes. The other fragment was macerated (in laminar flow) and the cell suspension, after adjusting the concentration (2 × 106), was plated to obtain cytokines produced by spleen cells that were measured by flow cytometry (Citometric Bead Array). Histopathological and quantitative analyzes in the spleen of the IE group showed an increase in the number of trabeculae and megakaryocytes, a decrease in reticular fibers, as well as important organizational changes in the white pulp and red pulp. Due to the decrease in the levels of cytokines measured and the result of the calculation of the ratio between the IFN-y and IL-10 cytokines (p = 0.0079) of the infected groups, we suggest that ethanol decreased the inflammatory and anti-inflammatory response generated by the infection (group IE, the production of cytokines was significantly decreased (p < 0.01). These changes demonstrate that ethanol ingestion interferes with some parameters of experimental S. mansoni infection, such as changes in splenic tissue and in the pattern of cytokine production.

Liposomes Enhance the Immunological Activity of Polygonatum Cyrtonema Hua Polysaccharides

Poor stability and difficult uptake of natural polysaccharides have been the main problems in their application. The purpose of this study was to optimize the preparation conditions of Polygonatum cyrtonema Hua polysaccharides liposomes (PCPL) and to investigate the immune enhancement activity of PCPL in vitro and in vivo, with a view to discovering new ways of natural polysaccharide application. The optimal preparation conditions of PCPL were as follows: the adding amount of Tween 80 of 0.5 %, the ultrasound time of 2 min and the ultrasound times of once. Under these conditions, the entrapment efficiency, drug loading rate and particle size of PCPL were 38.033 %±0.050, 2.172 %±0.003 and 146 nm, which indicated that PCPL with small particle size could be prepared by the reverse-phase evaporation method. Furthermore, PCPL promoted proliferation, phagocytosis, and secretion of nitric oxide and related cytokines in RAW264.7 cells. Moreover, PCPL improved spleen and thymus indices, increased the number or proportion of red blood cells, platelets, and lymphocytes in the blood, and ameliorated spleen and thymus atrophy in immunosuppressed mice. This study provides a new idea for applying Polygonatum cyrtonema Hua polysaccharides (PCP) and references for studying other polysaccharides.

The Possible Protective Role of Propolis on a Model of Restraint Stress in Rat Spleen Histological &amp; Immunohistochemical Study

Abstract Introduction Stress is a generic term that summarizes how psychosocial and environmental factors influence physical and mental well-being. The effects of stress on the immune system are complex and depend on the nature and duration of stress. Recently, the attention of researchers has been attracted to the use of propolis in many therapeutic fields including protection of the body from the effect of stress. Aim of the Work To study the effect of immobilization stress on the structure of spleen of restrained rats and the protective role of propolis. Materials and methods Thirty-two male rats (6-8) weeks old were used in this study. The animals were randomly divided to 4 groups, as follows: Group I (Control group), Group II in which rats were treated daily with propolis (3 g/kg) by gavage for 10 days. Group III (stress group): in which rats were subjected to restraint stress test 2 h/day for 10 days. Group IV (stress group with propolis): in which rats underwent the restraint stress test as in group III and were treated daily with propolis (3 g/kg) one hour before the start of the immobilization. At the end of experiment all animals were sacrificed; spleen specimens were collected from all rats and were subjected to microscopic &amp;immunohistochemical studies. Histomorphometry study and statistical analysis were also done. Results Compared to group I, some specimens of group III showed atrophy of spleen with significance decrease in surface area of PALS &amp; CD3 +ve cells immune reaction. These results were accompanied by significant decrease in surface area of the follicle with apparent decrease in CD20 +ve B lymphocytes immune reactivity. Moreover, apparent increase in CD68 immune reactivity in white pulp was recorded. Other specimens revaled thickened fibrosed splenic capsule and septa, widening and congestion of splenic sinusoid and prominent hemosiderin laden macrophage. Meanwhile group IV showed general improvement in spleen architecture with daily propolis intake. Conclusion Propolis is effective as a protective measure against the effect of restrained stress on spleen in adult rats.

Proinflammatory and Immunomodulatory Gene and Protein Expression Patterns in Spinal Cord and Spleen Following Acute and Chronic High Thoracic Injury.

In addition to paralysis and loss of sensation, high-level spinal cord injury (SCI) causes sympathetic dysfunction that can lead to autonomic dysreflexia (AD) and chronic immune suppression involving splenic leukopenia. Evidence has shown that treatment with either gabapentin or blockade of TNFα mitigates maladaptive plasticity and the underlying hemodynamic dysfunction, spleen atrophy, and immune dysfunction associated with AD. Because significant improvements long term was noted following treatments only during acute stages of recovery, we sought to systematically examine changes in proinflammatory and immunomodulatory cytokines to ascertain the reason. Adult female Wistar rats underwent complete T4 spinal transection before euthanasia at systematic intervals from 3 days to 8 weeks after injury. Using qRT-PCR and meso scale discovery (MSD) assays, the gene and protein expression of TNFα and IFNγ in the spleen, upper thoracic (T4-9) and lumbosacral (L5-S6) spinal cords were analyzed. We found that spleen atrophy occurs in a biphasic manner compared to naïve controls, with significant decreases in the spleen mass noted at 3 days and 8 weeks after injury. Splenic TNFα mRNA and protein levels did not change significantly over time, while IFNγ gene expression dipped acutely with trends for increased protein levels at more chronic time points. TNFα protein increased significantly only in thoracic spinal cord segments from 3 to 14 days post-injury. IFNγ mRNA and protein levels remained unelevated in injured spinal cords over time, with trends for increased protein levels at 2 and 8 weeks in the lumbosacral segments. Novel temporal-spatial cytokine expression profiles reveal that TNFα protein levels are increased solely in upper thoracic segments after high thoracic SCI, while IFNγ remains unaltered. Splenic leukopenia and latent systemic immunosuppression are not associated with altered TNFα or IFNγ expression in the spleen or spinal cord.

Nicotinamide Deteriorates Post-Stroke Immunodepression Following Cerebral Ischemia-Reperfusion Injury in Mice.

(1) Background: Inducing experimental stroke leads to biphasic immune responses, where the early activation of immune functions is followed by severe immunosuppression accompanied by spleen and thymus atrophy. Nicotinamide, a water-soluble B-group vitamin, is a known neuroprotectant against brain ischemia in animal models. We examined the effect of nicotinamide on the central and peripheral immune response in experimental stroke models. (2) Methods: Nicotinamide (500 mg/kg) or saline was intravenously administered to C57BL/6 mice during reperfusion after transiently occluding the middle cerebral artery or after LPS injection. On day 3, the animals were examined for behavioral performance and were then sacrificed to assess brain infarction, blood-brain barrier (BBB) integrity, and the composition of immune cells in the brain, thymus, spleen, and blood using flow cytometry. (3) Results: Nicotinamide reduced brain infarction and microglia/macrophage activation following MCAo (p < 0.05). Similarly, in LPS-injected mice, microglia/macrophage activation was decreased upon treatment with nicotinamide (p < 0.05), suggesting a direct inhibitory effect of nicotinamide on microglia/macrophage activation. Nicotinamide decreased the infiltration of neutrophils into the brain parenchyma and ameliorated Evans blue leakage (p < 0.05), suggesting that a decreased infiltration of neutrophils could, at least partially, be the result of a more integrated BBB structure following nicotinamide treatment. Our studies also revealed that administering nicotinamide led to retarded B-cell maturation in the spleen and subsequently decreased circulating B cells in the thymus and bloodstream (p < 0.05). (4) Conclusions: Cumulatively, nicotinamide decreased brain inflammation caused by ischemia-reperfusion injury, which was mediated by a direct anti-inflammatory effect of nicotinamide and an indirect protective effect on BBB integrity. Administering nicotinamide following brain ischemia resulted in a decrease in circulating B cells. This warrants attention with respect to future clinical applications.

Antitumor Profile of Combined Matricaria recutita Flower Extract and 5-Fluorouracil Chemotherapy in Sarcoma 180 In Vivo Model.

Medicinal plants have been commonly associated with chemotherapeutic treatments, as an approach to reduce the toxicological risks of classical anticancer drugs. The objective of this study was to evaluate the effects of combining the antineoplastic drug 5-fluorouracil (5-FU) with Matricaria recutita flowers extract (MRFE) to treat mice transplanted with sarcoma 180. Tumor inhibition, body and visceral mass variation, biochemical, hematological, and histopathological parameters were evaluated. The isolated 5-FU, 5-FU+MRFE 100 mg/kg/day, and 5-FU+MRFE 200 mg/kg/day reduced tumor growth; however, 5-FU+MRFE 200 mg/kg/day showed a more significant tumor reduction when compared to 5-FU alone. These results corroborated with the analysis of the tumor histopathological and immunodetection of the Ki67 antigen. In the toxicological analysis of the association 5-FU+MRFE 200 mg/kg/day, an intense loss of body mass was observed, possibly as a result of diarrhea. In addition, spleen atrophy, with a reduction in white pulp, leukopenia and thrombocytopenia, was observed in the 5-FU groups alone and associated with MRFE 200 mg/kg/day; however, there was no statistical difference between these groups. Therefore, the MRFE 200 mg/kg/day did not interfere in myelosuppressive action of 5-FU. In hematological analysis, body and visceral mass variation and biochemical parameters related to renal (urea and creatinine) and cardiac (CK-MB) function, no alteration was observed. In biochemical parameters related to liver function enzymes, there was a reduction in aspartate transaminase (AST) values in the 5-FU groups alone and associated with MRFE 200 mg/kg/day; however, there was no statistical difference between these groups. Therefore, the MRFE 200 mg/kg/day does not appear to influence enzyme reduction. The results of this study suggest that the association between the 5-FU+MRFE 200 can positively interfere with the antitumor activity, promoting the antineoplastic-induced reduction in body mass, while minimizing the toxicity of chemotherapy.

Hematopoietic Effects of Angelica gigas Nakai Extract on Cyclophosphamide-Induced Myelosuppression.

Myelosuppression is a major adverse effect of chemotherapy. With the increasing number of cancer patients worldwide, there is a growing interest in therapeutic approaches that reduce the adverse effects of chemotherapy. Angelica gigas Nakai (AGN) roots have been widely used in oriental medicine to treat blood-related diseases, including cancer. However, the effects of AGN on myelosuppression have not been studied. Here, we investigated the effects of AGN ethanol extract (AGNEX) on cyclophosphamide-induced myelosuppression. AGNEX treatment significantly decreased white blood cell levels while increasing red blood cell and platelet levels in the peripheral blood. It inhibited thymus and spleen atrophy. It also enhanced serum levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α. qRT-PCR results showed that AGNEX decreased the expression of IL-1b and stem cell factor (SCF) in the bone marrow (BM) while increasing the mRNA expression of IL-3 and IL-6 in the spleen. Although AGNEX did not significantly decrease apoptosis and cell cycle arrest in the BM and splenocytes, AGNEX plays a positive role in cyclophosphamide-induced myelosuppression. AGNEX administration increased BM cells in the femur while decreasing apoptotic BM cells. These findings suggest that AGNEX could be used to treat myelosuppression and as a combination therapy in cancer patients.

Preventive Mechanism of Lycopene on Intestinal Toxicity Caused by Cyclophosphamide Chemotherapy in Mice by Regulating TLR4-MyD88/TRIF-TRAF6 Signaling Pathway and Gut-Liver Axis.

Cyclophosphamide (CYC) is the first-line chemotherapy drug for cancer in clinical practice, and its intestinal toxicity seriously affects the treatment effect and prognosis of patients. Lycopene (LP) is the main pigment of ripe tomatoes and has strong antioxidant activity. However, the mechanism by which LP prevents CYC-induced intestinal injury remains unclear. The aim of this study was to investigate the mechanism of LP in preventing intestinal toxicity caused by CYC chemotherapy in mice. The results showed that LP significantly prevented spleen and thymus atrophy induced by CYC. In terms of intestinal injury, LP significantly increased the levels of superoxide dismutase (SOD), secretory immunoglobulin A (sIgA), interleukin (IL)-4, IL-12, and interferon (IFN)-γ, decreased the content of lipid oxidation (MDA), upregulated the protein expressions of toll-like receptors 4 (TLR4), myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF6), toll/IL-1receptor domain containing adaptor protein inducing IFN-β (TRIF), p-P38 MAPK (P38), and p-nuclear factor kappa-B (NF-κB) p65, and improved the small intestine tissue injury induced by CYC. In terms of liver injury, LP significantly increased the content of glutathione (GSH), decreased the contents of MDA, nitric oxide (NO), IL-1β, IL-6, and tumor necrosis factor (TNF)-α, and repaired the liver tissue injury induced by CYC. Importantly, 10 mg/kg LP significantly prevented intestinal microbiota dysregulation in CYC mice. These results suggested that LP significantly prevented intestinal injury induced by CYC in mice by regulating the TLR4-MyD88/TRIF-TRAF6 signaling pathway and gut-liver axis.

The protective effect of the spleen in sickle cell patients. A comparative study between patients with asplenia/hyposplenism and hypersplenism.

Sickle cell disease (SCD) is caused by a point mutation in the beta-globin gene. SCD is characterized by chronic hemolytic anemia, vaso-occlusive events leading to tissue ischemia, and progressive organ failure. Chronic inflammatory state is part of the pathophysiology of SCD. Patients with SCD have extremely variable phenotypes, from mild disease to severe complications including early age death. The spleen is commonly injured in SCD. Early splenic dysfunction and progressive spleen atrophy are common. Splenomegaly and hypersplenism can also occur with the loss of the crucial splenic function. Acute, life-threatening spleen-related complications in SCD are well studied. The association of laboratory parameters with the spleen status including hyposplenism, asplenia, and splenomegaly/hypersplenism, and their implication in vaso-occlusive crisis and long-term complications in SCD remain to be determined. We evaluated the association between the spleen status with clinical and laboratory parameters in 31 SCD patients: Group a) Patients with asplenia/hyposplenism (N = 22) (including auto-splenectomy and splenectomized patients) vs. Group b) patients with splenomegaly and or hypersplenism (N = 9). Laboratory studies included: Complete Blood Count, reticulocyte count, iron metabolism parameters, C Reactive Protein (CRP), Hb variant distribution, and D-dimer. Metabolic and morphological red blood cell (RBC) studies included: density gradient (by Percoll), glucose consumption, lactate release, and K+ leakage, fetal RBC (F-Cells) and F-Reticulocytes, annexinV+, CD71+, oxidative stress measured by GSH presence in RBC and finally Howell Jolly Bodies count were all analyzed by Flow Cytometry. Scanning electron microscopy analysis of RBC was also performed. Patients with asplenia/hyposplenism showed significantly higher WBC, platelet, Hematocrit, hemoglobin S, CRP, D-dimer, Gamma Glutamyl Transferase (GGT), cholesterol, transferrin, annexin V+ RBCs, CD71+ RBCs, together with a markedly lower F Reticulocyte levels in comparison with splenomegaly/hypersplenism patients. In summary, important differences were also found between the groups in the studied RBCs parameters. Further studies are required to elucidate the effect of the spleen including hyper and hypo-splenia on laboratory parameters and in clinical manifestations, vascular pathology, and long-term complications of SCD. The benefits and risks of splenectomy compared to chronic transfusion need to be evaluated in clinical trials and the standard approach managing hypersplenism in SCD patients should be re-evaluated.

Brain-derived programmed death-ligand 1 mediates immunosuppression post intracerebral hemorrhage

Immunosuppression commonly occurs after a stroke, which is believed to be associated with the increased risk of infectious comorbidities of stroke patients, while the mechanisms underlying post-stroke immunosuppression is yet to be elucidated. In the brains of intracerebral hemorrhage (ICH) patients and murine ICH models, we identified that neuron-derived programmed death-ligand 1 (PD-L1) is reduced in the perihematomal area, associating increased soluble PD-L1 level in the peripheral blood. ICH induced a significant decrease of T and natural killer (NK) cell numbers in the periphery with an upregulation of programed death-1 (PD-1) in these cells. Blocking PD-1 pathway with an anti-PD1 monoclonal antibody prevented the T and NK cell compartment contraction and spleen atrophy post-ICH, with reduced pulmonary bacterial burden and improved neurological outcome. Thus, we here identified that brain-derived PD-L1 as a new mechanism driving post-stroke immunosuppression, and anti-PD1 treatment could be potentially developed to reducing the risk of post-stroke infections.

PB2222: THE PROTECTIVE EFFECT OF THE SPLEEN IN SICKLE CELL PATIENTS. A COMPARATIVE STUDY BETWEEN PATIENTS WITH ASPLENIA AND HYPERSPLENISM.

Background: Sickle cell disease (SCD) is caused by a point mutation in the beta globin gene. SCD is characterized by chronic hemolytic anemia, vaso-occlusive events leading to tissue ischemia and progressive organ failure. A chronic inflammatory state is part of the pathophysiology of SCD. Patients with SCD have extremely variable phenotypes, from a mild disease to severe complications including early age death. The spleen is commonly injured in SCD. Early splenic dysfunction and progressive spleen atrophy are common. Splenomegaly and hypersplenism, can also occur with loss of the crucial splenic function. Acute, life-threatening spleen-related complications in SCD are well studied. The implications of the spleen status including asplenia and splenomegaly/ hypersplenism in vaso- occlusive crisis and long-term complications in SCD remain to be determined. Aims: In this study, we compared blood parameters and RBC properties of SCD patients and compared the results between patients with asplenia, to patients with splenomegaly/hypersplenism. In addition, we implemented novel, non-routinely used methods for the evaluation of the functional status of the spleen in those patients. Methods: We evaluated the association between the spleen status with clinical and laboratory parameters in 31 SCD patients divided into two groups: Group a) Patients with asplenia (N=22) (including auto-splenectomy and patients that were splenectomized) vs. Group b) patients with Splenomegaly and or Hypersplenism (N=9). Laboratory studies included: CBC, reticulocyte count, iron metabolism parameters, CRP, Hb variant distribution and D-dimer. Metabolic and morphological red blood cell (RBC) studies included: density gradient (by Percoll), glucose consumption, lactate release and K+ leakage; fetal RBC (F-Cells) and F Reticulocytes, annexin V+, CD71+, oxidative stress measured by GSH presence in RBC and finally HJB count were all analyzed by FC. SEM analysis of RBC was also performed. Results: Patients in group (a) showed significantly higher WBC, platelet, HCT, hemoglobin S, CRP, D-dimer, GGT, cholesterol and transferrin levels than patients in group (b). The percent of hyperchromic RBCs, F-Reticulocytes were lower in patients with asplenia. Important differences were also found between the groups in the studied RBCs metabolic parameters. Summary/Conclusion: Further studies are required to elucidate the effect of the spleen including hyper and hypo-splenia in vaso-occlusive crisis, vascular pathology, and long-term complications of SCD. The benefits and risks of splenectomy compared to chronic transfusion need to be evaluated in clinical trials and the standard approach to manage hypersplenism in SCD patients should be re-evaluated.

Heightened levels of circulating cell-free DNA predict aggressive onset of experimental glioblastoma

Abstract Glioblastoma (GBM) is an incurable and aggressive form of brain cancer that is associated with severe peripheral immunosuppression. This immunosuppression is a critical barrier to patient survival and the success of immune modulatory therapies. Using the murine GL261 model of GBM, we recapitulated major features of peripheral immunosuppression observed in patients including spleen atrophy, T cell lymphopenia, and T cell sequestration within the bone marrow. We determined that peripheral immunosuppression in GBM is multifaceted and involves release of novel circulating soluble factors that are found in the serum of glioma-bearing mice. This high molecular weight species potently inhibits T cell proliferation in vitro. Cell-free extracellular DNA has been recently identified as an immune suppressive factor in circulation. We, therefore, assessed cell-free DNA levels in the GL261 model. We determined that serum isolated from glioma-bearing mice harbor significantly higher concentrations of double stranded and single stranded cell-free DNA compared to healthy controls. Serial assessment of DNA concentrations in serum of glioma-bearing mice indicated that the most prominent increase was concurrent with end-stage disease. These findings provide a tractable approach to investigate the cellular source and immune suppressive effects of cell-free DNA in the leading murine model of GBM. Supported by K99NS117799

The immunotoxicity of decabromodiphenyl ether (BDE-209) on broiler chicks by transcriptome profiling analysis

Decabromodiphenyl ether (BDE-209) has drawn significant attention due to its suppression of immune functions in animals and even humans. In order to explore the mechanism through which BDE-209 affects the immune system, broiler chicks were fed a diet containing various concentrations of BDE-209 (0, 0.004, 0.04, 0.4, and 4 g/kg) for 42 days. Histopathological observations of immune organs found damaged and necrotic lymphocytes in the spleen and bursa, and losses of lymphoid cells in thymic gland. The activities of catalase, glutathione, glutathione peroxidase, and superoxide dismutase in both the spleen and serum were affected by BDE-209. Obvious bioaccumulation effect was found in spleen tissues (high to 1339 ± 181.9 μg/kg). Furthermore, transcriptome sequencing analyses of the spleen identified 424 upregulated and 301 downregulated DEGs, and the cytokine-cytokine receptor interaction signal pathway was most significantly enriched based on the Kyoto Encyclopedia of Genes and Genomes database. Quantitative real-time PCR affirmed the decreased expressions of interleukin IL18, IL18R1, IL18RAP, IL21, as well as interferon gamma IFNG and tumor necrosis factor superfamily members TNFSF8, indicating significant interference to immunomodulation function and possible disease progression in inflammatory effects resulting from BDE-209 exposure. The immunotoxicity of BDE-209 may cause the suppression of immune and physiological functions of spleen cells, leading to inflammation and apoptosis and ultimately spleen atrophy.