Mononuclear Phagocytic Cells Research Articles

Fluorescent Crimean-Congo hemorrhagic fever virus illuminates tissue tropism patterns and identifies early mononuclear phagocytic cell targets in Ifnar-/- mice.

Crimean-Congo hemorrhagic fever virus (CCHFV, order Bunyavirales, family Nairoviridae, genus Orthonairovirus) is the tick-borne etiological agent of Crimean-Congo hemorrhagic fever (CCHF) in humans. Animals are generally susceptible to CCHFV infection but refractory to disease. Small animal models are limited to interferon-deficient mice, that develop acute fatal disease following infection. Here, using a ZsGreen1- (ZsG) expressing reporter virus (CCHFV/ZsG), we examine tissue tropism and dissemination of virus in interferon-α/β receptor knock-out (Ifnar-/-) mice. We demonstrate that CCHFV/ZsG retains in vivo pathogenicity comparable to wild-type virus. Interestingly, despite high levels of viral RNA in all organs assessed, 2 distribution patterns of infection were observed by both fluorescence and immunohistochemistry (IHC), corresponding to the permissiveness of organ tissues. To further investigate viral dissemination and to temporally define cellular targets of CCHFV in vivo, mice were serially euthanized at different stages of disease. Flow cytometry was used to characterize CCHFV-associated alterations in hematopoietic cell populations and to classify infected cells in the blood, lymph node, spleen, and liver. ZsG signal indicated that mononuclear phagocytic cells in the lymphatic tissues were early targets of infection; in late-stage infection, overall, the highest levels of signal were detected in the liver, and ZsG was found in both antigen-presenting and lymphocyte cell populations.

Oral treatment with T6-loaded yeast cell wall particles reduces the parasitemia in murine visceral leishmaniasis model

Yeast cell wall particles isolated from Saccharomyces cerevisiae (scYCWPs) have a rich constitution of β-glucan derived from the cell wall. After removing intracellular contents, β-glucan molecules are readily recognized by dectin-1 receptors, present on the cytoplasmic membrane surface of the mononuclear phagocytic cells and internalized. Leishmania spp. are obligate intracellular parasites; macrophages are its primary host cells. An experimental murine model of visceral leishmaniasis caused by L. infantum was used to evaluate the antileishmanial activity of oral administration of these particles. A low-water soluble thiophene previously studied in vitro against L. infantum was entrapped into scYCWPs to direct it into the host cell, in order to circumvent the typical pharmacokinetic problems of water-insoluble compounds. We found that scYCWPs + T6 reduced the parasitic burden in the liver and spleen. There was an increase in IFN-γ levels related to nitric oxide production, explaining the reduction of the L. infantum burden in the tissue. Histological analysis did not show signals of tissue inflammation and biochemical analysis from plasma did not indicate signals of cytotoxicity after scYCWPs + T6 treatment. These findings suggested that scYCWPs + T6 administered through oral route reduced the parasitic burden without causing toxic effects, satisfying requirements for development of new strategies to treat leishmaniasis.

Leukocyte-specific siRNA delivery revealing IRF8 as a potential anti-inflammatory target

Interferon regulatory factor 8 (IRF8) protein plays a critical role in the differentiation, polarization, and activation of mononuclear phagocytic cells. In light of previous studies, we explored the therapeutic potential of IRF8 inhibition as immunomodulatory therapy for inflammatory bowel disease (IBD). To this end, we utilized siRNA-loaded lipid-based nanoparticles (siLNPs) and demonstrated a ∼90% reduction of IRF8 mRNA levels in vitro (PV < 0.0001), alongside a notable reduction in IRF8 protein. Moreover, silencing IRF8 ex vivo in splenocytes lead to a profound downregulation of IRF8 protein, followed by an immunomodulatory effect, as represented by a decrease in the secretion of TNFα, IL6 and IL12/IL23 (IL12p40) proinflammatory cytokines (PV = 0.0045, 0.0330, <0.0001, respectively). In order to silence IRF8 in vivo, selectively in inflammatory leukocytes, we used siLNPs that were coated with anti-Ly6C antibodies via our recently published ASSET targeting approach. Through this strategy, we have demonstrated a selective binding of the targeted-LNPs (T-LNPs) to Ly6C + inflammatory leukocytes. Finally, an immunomodulatory effect was demonstrated in vivo in an IBD mouse model with a profound decrease of TNFα, IL6, IL12/IL23, and IL1β pro-inflammatory cytokines (n = 5, PV < 0.0001, <0.0001, <0.0001, 0.02, respectively) and an improvement of colon-morphology as assessed by colon-length measurements and colonoscopy (PV < 0.0001). Overall, using antibody-targeted siLNPs, we showed a notable reduction of IRF8 mRNA and protein and demonstrated a targeted immunomodulation therapeutic effect ex vivo and in vivo, in the DSS colitis model. We claim that a selective silencing of IRF8 in inflammatory leukocytes (such as Ly6C+) may serve as a therapeutic approach for treating inflammatory disorders.

Nilotinib: A Tyrosine Kinase Inhibitor Mediates Resistance to Intracellular Mycobacterium Via Regulating Autophagy.

Nilotinib, a tyrosine kinase inhibitor, has been studied extensively in various tumor models; however, no information exists about the pharmacological action of nilotinib in bacterial infections. Mycobacterium bovis (M. bovis) and Mycobacterium avium subspecies paratuberculosis (MAP) are the etiological agents of bovine tuberculosis and Johne’s disease, respectively. Although M. bovis and MAP cause distinct tissue tropism, both of them infect, reside, and replicate in mononuclear phagocytic cells of the infected host. Autophagy is an innate immune defense mechanism for the control of intracellular bacteria, regulated by diverse signaling pathways. Here we demonstrated that nilotinib significantly inhibited the intracellular survival and growth of M. bovis and MAP in macrophages by modulating host immune responses. We showed that nilotinib induced autophagic degradation of intracellular mycobacterium occurred via the inhibition of PI3k/Akt/mTOR axis mediated by abelson (c-ABL) tyrosine kinase. In addition, we observed that nilotinib promoted ubiquitin accumulation around M. bovis through activation of E3 ubiquitin ligase parkin. From in-vivo experiments, we found that nilotinib effectively controlled M. bovis growth and survival through enhanced parkin activity in infected mice. Altogether, our data showed that nilotinib regulates protective innate immune responses against intracellular mycobacterium, both in-vitro and in-vivo, and can be exploited as a novel therapeutic remedy for the control of M. bovis and MAP infections.

SUN-114 Microglia Interact with Hypothalamic Progenitors during Development and Are Required for Proper Energy Balance

Microglia are the resident mononuclear phagocytic immune cells of the central nervous system (CNS), and are primarily responsible for responding to neural insults and disposing of cellular debris. However, over the last decade studies are showing that microglia are highly dynamic cells involved in various critical neurodevelopmental processes. We set out to study microglia dynamics in the embryonic hypothalamus given that the hypothalamus is responsive to external stressors and critical for maintaining homeostatic processes such as energy balance, thirst, food intake, reproduction, and circadian rhythms. Using slice culture and time-lapse imaging we showed that hypothalamic microglia are highly dynamic during embryogenesis, constantly surveying their environment and often interacting with radial glia precursor cells that line the third ventricle and are responsible for generating hypothalamic neurons, oligodendrocytes, astrocytes, and tanycytes. Moreover, given that microglia colonize the embryonic brain alongside key steps of hypothalamic development, we wanted to test whether microglia are required for the proper establishment of this brain region. To eliminate microglia from the fetal brain, we treated pregnant dams with the Colony-stimulating factor-1 (Csf1r) inhibitor PLX5622, as Csf1r is expressed by microglia and is required for their proliferation, differentiation, and survival. Embryonic microglia depletion resulted in a decreased litter size, as well as an increase in the number of pups that died within the first two postnatal days of life. In pups that survived, the elimination of microglia in the fetal brain resulted in a decrease in the number of Pro-opiomelanocortin (POMC) neurons and a concomitant accelerated weight gain, suggesting that microglia could be important for the development of hypothalamic satiety centers. Depletion of microglia during embryogenesis also had long-term sex-specific effects on behaviour. Furthermore, hypothalamic microglia appear to be sensitive to the endocrine disruptor Bisphenol A during embryogenesis. Taken together, these data demonstrate an important role for microglia during the development of the embryonic hypothalamus.

Langerhans cell histiocytosis of the hip in children.

Eight year old girl was referred to our consultation for a lameness with a flessum of the left hip with fever (38.5°C). Biology showed an inflammatory syndroma (CRP: 29 mg/l). Pelvic X-ray showed an osteolysis of the roof of the left acetabulum with regular contour (A). Magnetic resonance imaging (MRI) showed tissue thinning and damage to the roof of the left acetabulum (B). A scanno-guided biopsy was performed, anatomopathological study confirmed the diagnosis of Langerhans cell histiocytosis. A discharge, with traction was done. The child has improved and biology has normalized. The radiograph of the hip after 1 year showed a filling of the gap (C). Langerha's cell histiocytosis is a proliferation of mononuclear phagocytic cells. It is also called eosinophilic granuloma. It is often located at the skull and spine. The localization at the hip represents only 8% of the cases it is especially supra-acetabular it's spontaneous evolution is favorable.

Isolation and Phenotypic Characterization of Inflammatory Cells from Clinical Samples: Purification of Macrophages from Trypanosoma cruzi-Infected Hearts.

Trypanosoma cruzi, the causal agent of chronic Chagas cardiomyopathy, exhibits an important tropism for cardiac tissue. In consequence, T. cruzi experimental infection represents a unique model to study cardiac macrophage behavior and effector functions during either acute or chronic immune response. In this chapter we describe a protocol to isolate immune cells from T. cruzi-infected murine cardiac tissue and to determine the percentage, absolute number, phenotype, and functionality of monocytes and macrophages by using flow cytometry. Moreover, we describe the parameters to discriminate between resident and infiltrating mononuclear phagocytic cells within infected hearts. The investigations in this field will provide mechanistic insights about the roles of these innate immune cells in the context of a clinically relevant target tissue.

Zinc-dependent substrate-level phosphorylation powers Salmonella growth under nitrosative stress of the innate host response.

The metabolic processes that enable the replication of intracellular Salmonella under nitrosative stress conditions engendered in the innate response of macrophages are poorly understood. A screen of Salmonella transposon mutants identified the ABC-type high-affinity zinc uptake system ZnuABC as a critical determinant of the adaptation of Salmonella to the nitrosative stress generated by the enzymatic activity of inducible nitric oxide (NO) synthase of mononuclear phagocytic cells. NO limits the virulence of a znuB mutant in an acute murine model of salmonellosis. The ZnuABC transporter is crucial for the glycolytic function of fructose bisphosphate aldolase, thereby fueling growth of Salmonella during nitrosative stress produced in the innate response of macrophages. Our investigations demonstrate that glycolysis mediates resistance of Salmonella to the antimicrobial activity of NO produced in an acute model of infection. The ATP synthesized by substrate-level phosphorylation at the payoff phase of glycolysis and acetate fermentation powers the replication of Salmonella experiencing high levels of nitrosative stress. In contrast, despite its high potential for ATP synthesis, oxidative phosphorylation is a major target of inhibition by NO and contributes little to the antinitrosative defenses of intracellular Salmonella. Our investigations have uncovered a previously unsuspected conjunction between zinc homeostasis, glucose metabolism and cellular energetics in the adaptation of intracellular Salmonella to the reactive nitrogen species synthesized in the innate host response.

The fungal peptide toxin Candidalysin activates the NLRP3 inflammasome and causes cytolysis in mononuclear phagocytes

Clearance of invading microbes requires phagocytes of the innate immune system. However, successful pathogens have evolved sophisticated strategies to evade immune killing. The opportunistic human fungal pathogen Candida albicans is efficiently phagocytosed by macrophages, but causes inflammasome activation, host cytolysis, and escapes after hypha formation. Previous studies suggest that macrophage lysis by C. albicans results from early inflammasome-dependent cell death (pyroptosis), late damage due to glucose depletion and membrane piercing by growing hyphae. Here we show that Candidalysin, a cytolytic peptide toxin encoded by the hypha-associated gene ECE1, is both a central trigger for NLRP3 inflammasome-dependent caspase-1 activation via potassium efflux and a key driver of inflammasome-independent cytolysis of macrophages and dendritic cells upon infection with C. albicans. This suggests that Candidalysin-induced cell damage is a third mechanism of C. albicans-mediated mononuclear phagocyte cell death in addition to damage caused by pyroptosis and the growth of glucose-consuming hyphae.

The latitude-dependent autoimmune disease risk genes ZMIZ1 and IRF8 regulate mononuclear phagocytic cell differentiation in response to vitamin D.

Epidemiological, molecular and genetic studies have indicated that high serum vitamin D levels are associated with lower risk of several autoimmune diseases. The vitamin D receptor (VDR) binding sites in monocytes and dendritic cells (DCs) are more common in risk genes for diseases with latitude dependence than in risk genes for other diseases. The transcription factor genes Zinc finger MIZ domain-containing protein 1 (ZMIZ1) and interferon regulatory factor 8 (IRF8)-risk genes for many of these diseases-have VDR binding peaks co-incident with the risk single nucleotide polymorphisms (SNPs). We show these genes are responsive to vitamin D: ZMIZ1 expression increased and IRF8 expression decreased, and this response was affected by genotype in different cell subsets. The IL10/IL12 ratio in tolerogenic DCs increased with vitamin D. These data indicate that vitamin D regulation of ZMIZ1 and IRF8 in DCs and monocytes contribute to latitude-dependent autoimmune disease risk.

Abstract SY18-02: The relationship between Batf3-DC and antitumor T-cell responses

Abstract Cancer immunotherapy has attracted enormous attention and investment, stimulated by successes of immune checkpoint blockade drugs, such as anti-CTLA4 and anti-PD-1. Despite the potential of immunotherapy to eradicate even metastatic cancer, only a minority of cancer patients respond to checkpoint blockade agents. Clinical and preclinical data provide evidence that the presence of tumor-specific CD8 T cells within the tumor microenvironment (TME) is critical for the response to checkpoint blockade. Another major component of tumor-infiltrating immune systems is the mononuclear phagocytic cell compartment, which provides both pro- and antitumoral properties, depending on its composition. A rare subset of conventional dendritic cells, marked by CD103 and the transcription factor Batf3, is required for the uptake, transport, and presentation of tumor-derived antigens to CD8 T cells in the tumor-draining lymph node. Tumors lacking CD103+ dendritic cells do not mount spontaneous antitumor immune responses and fail to respond to checkpoint blockade therapy. Moreover, we observed that absence of this subset of DC is mediating resistance to adoptive T-cell transfer. Analysis of tumor-residing CD103+ dendritic cells revealed that this small subset of cells provides the predominant source of effector T-cell recruiting chemokines (CXCL9 and 10) and is a critical component of the TME. This observation imposes a more detailed and refined analysis of the contribution of tumor-residing dendritic cells to the local antitumor immune response. Citation Format: Stefani Spranger. The relationship between Batf3-DC and antitumor T-cell responses [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr SY18-02.

Characterization of kidney CD45intCD11bintF4/80+MHCII+CX3CR1+Ly6C- "intermediate mononuclear phagocytic cells".

Kidney immune cells play important roles in pathogenesis of many diseases, including ischemia-reperfusion injury (IRI) and transplant rejection. While studying murine kidney T cells, we serendipitously identified a kidney mononuclear phagocytic cell (MPC) subset characterized by intermediate surface expression of CD45 and CD11b. These CD45intCD11bint MPCs were further identified as F4/80+MHCII+CX3CR1+Ly6C- cells, comprising ~17% of total CD45+ cells in normal mouse kidney (P < 0.01) and virtually absent from all other organs examined except the heart. Systemic clodronate treatment had more significant depletive effect on the CD45intCD11bint population (77.3%±5.9%, P = 0.03) than on CD45highCD11b+ population (14.8%±16.6%, P = 0.49). In addition, CD45intCD11bint MPCs had higher phagocytic function in the normal kidney (35.6%±3.3% vs. 24.1%±2.2%, P = 0.04), but lower phagocytic capacity in post-ischemic kidney (54.9%±1.0% vs. 67.8%±1.9%, P < 0.01) compared to the CD45highCD11b+ population. Moreover, the CD45intCD11bint population had higher intracellular production of the pro-inflammatory tumor necrosis factor (TNF)-α (58.4%±5.2% vs. 27.3%±0.9%, P < 0.001) after lipopolysaccharide (LPS) stimulation and lower production of the anti-inflammatory interleukin (IL)-10 (7.2%±1.3% vs. 14.9%±2.2%, P = 0.02) following kidney IRI, suggesting a functional role under inflammatory conditions. The CD45intCD11bint cells increased early after IRI, and then abruptly decreased 48h later, whereas CD45highCD11b+ cells steadily increased after IRI before declining at 72h (P = 0.03). We also identified the CD45intCD11bint MPC subtype in human kidney. We conclude that CD45intCD11bint F4/80+MHCII+CX3CR1+Ly6C-population represent a unique subset of MPCs found in both mouse and human kidneys. Future studies will further characterize their role in kidney health and disease.

Development of in situ hybridization for detection of elephant endotheliotropic herpesvirus in Asian elephants.

Elephant endotheliotropic herpesvirus (EEHV) is one of the most important viral infectious diseases affecting the elephant population worldwide, especially juveniles and young adults. We developed a chromogenic in situ hybridization (ISH) test for detection of EEHV in Asian elephants ( Elephas maximus). Digoxigenin (DIG) DNA probes from the polymerase and terminase genes of EEHV were synthesized using a PCR DIG-labeling method, and detection of hybridized probe to target EEHV DNA was carried out by anti-DIG immunolabeling. Distribution of EEHV-1A and EEHV-4 genomes was found to be prominent in mononuclear phagocytic cells of spleen and endothelial cells of visceral organs. ISH enables the detection of EEHV infection and has applications in understanding pathogenesis of EEHV in Asian elephants.

Production of antibody against elephant endotheliotropic herpesvirus (EEHV) unveils tissue tropisms and routes of viral transmission in EEHV-infected Asian elephants

Elephant endotheliotropic herpesvirus (EEHV) is one of the most devastating viral infectious diseases in elephants worldwide. To date, it remains unclear how elephants get infected by the virus, where the virus persists, and what mechanisms drive the pathogenesis of the disease. The present study was aimed to develop an antibody against glycoprotein B (gB) of EEHV, investigate the EEHV tissue tropisms, and provide the possible routes of EEHV transmission in Asian elephants. Samples from elephant organs that had died from EEHV1A and EEHV4 infections, peripheral blood mononuclear cells (PBMC) from EEHV4- and non-EEHV-infected calves were used in this study. The results of western immunoblotting indicated that the antibody can be used for detection of gB antigens in both EEHV1A- and EEHV4-infected samples. Immunohistochemical detection indicated that the EEHV gB antigens were distributed mainly in the epithelial cells of the salivary glands, stomach and intestines. Immunofluorescence test of PBMC for EEHV gB in the EEHV4-infected calf indicated that the virus was observed predominantly in the mononuclear phagocytic cells. The findings in the present study unveil tissue tropisms in the EEHV1A- and EEHV4-infected calves and point out that saliva and intestinal content are likely sources for virus transmission in EEHV-infected Asian elephants.

MicroRNA 27a-3p Regulates Antimicrobial Responses of Murine Macrophages Infected by Mycobacterium avium subspecies paratuberculosis by Targeting Interleukin-10 and TGF-β-Activated Protein Kinase 1 Binding Protein 2.

Mycobacterium avium subspecies paratuberculosis (MAP) persistently survive and replicate in mononuclear phagocytic cells by adopting various strategies to subvert host immune response. Interleukin-10 (IL-10) upregulation via inhibition of macrophage bactericidal activity is a critical step for MAP survival and pathogenesis within the host cell. Mitogen-activated protein kinase p38 signaling cascade plays a crucial role in the elevation of IL-10 and progression of MAP pathogenesis. The contribution of microRNAs (miRNAs) and their influence on the activation of macrophages during MAP pathogenesis are still unclear. In the current study, we found that miRNA-27a-3p (miR-27a) expression is downregulated during MAP infection both in vivo and in vitro. Moreover, miR-27a is also downregulated in toll-like receptor 2 (TLR2)-stimulated murine macrophages (RAW264.7 and bone marrow-derived macrophage). ELISA and real-time qRT-PCR results confirm that overexpression of miR-27a inhibited MAP-induced IL-10 production in macrophages and upregulated pro-inflammatory cytokines, while miR-27a inhibitor counteracted these effects. Luciferase reporter assay results revealed that IL-10 and TGF-β-activated protein kinase 1 binding protein 2 (TAB 2) are potential targets of miR-27a. In addition, we demonstrated that miR-27a negatively regulates TAB 2 expression and diminishes TAB 2-dependent p38/JNK phosphorylation, ultimately downregulating IL-10 expression in MAP-infected macrophages. Furthermore, overexpression of miR-27a significantly inhibited the intracellular survival of MAP in infected macrophages. Our data show that miR-27a augments antimicrobial activities of macrophages and inhibits the expression of IL-10, demonstrating that miR-27a regulates protective innate immune responses during MAP infection and can be exploited as a novel therapeutic target in the control of intracellular pathogens, including paratuberculosis.

New Insights into the Immunobiology of Mononuclear Phagocytic Cells and Their Relevance to the Pathogenesis of Cardiovascular Diseases.

Macrophages are the primary immune cells that reside within the myocardium, suggesting that these mononuclear phagocytes are essential in the orchestration of cardiac immunity and homeostasis. Independent of the nature of the injury, the heart triggers leukocyte activation and recruitment. However, inflammation is harmful to this vital terminally differentiated organ with extremely poor regenerative capacity. As such, cardiac tissue has evolved particular strategies to increase the stress tolerance and minimize the impact of inflammation. In this sense, growing evidences show that mononuclear phagocytic cells are particularly dynamic during cardiac inflammation or infection and would actively participate in tissue repair and functional recovery. They respond to soluble mediators such as metabolites or cytokines, which play central roles in the timing of the intrinsic cardiac stress response. During myocardial infarction two distinct phases of monocyte influx have been identified. Upon infarction, the heart modulates its chemokine expression profile that sequentially and actively recruits inflammatory monocytes, first, and healing monocytes, later. In the same way, a sudden switch from inflammatory macrophages (with microbicidal effectors) toward anti-inflammatory macrophages occurs within the myocardium very shortly after infection with Trypanosoma cruzi, the causal agent of Chagas cardiomyopathy. While in sterile injury, healing response is necessary to stop tissue damage; during an intracellular infection, the anti-inflammatory milieu in infected hearts would promote microbial persistence. The balance of mononuclear phagocytic cells seems to be also dynamic in atherosclerosis influencing plaque initiation and fate. This review summarizes the participation of mononuclear phagocyte system in cardiovascular diseases, keeping in mind that the immune system evolved to promote the reestablishment of tissue homeostasis following infection/injury, and that the effects of different mediators could modulate the magnitude and quality of the immune response. The knowledge of the effects triggered by diverse mediators would serve to identify new therapeutic targets in different cardiovascular pathologies.

Virulence of Mycobacterium avium Subsp. hominissuis Human Isolates in an in vitro Macrophage Infection Model

Mycobacterium avium subsp. hominissuis (MAH) is an environmental opportunistic pathogen for humans and swine worldwide; in humans, the vast majority of MAH infections is due to strains belonging to specific genotypes, such as the internal transcribed spacer (ITS)-sequevars Mav-A and Mav-B that mostly cause pulmonary infections in elderly patients and severe disseminated infections in acquired immunodeficiency syndrome patients, respectively. To test whether the different types of infections in distinct patients' populations might reflect a different virulence of the infecting genotypes, MAH human isolates, genotyped by ITS sequencing and MIRU-VNTR minisatellite analysis, were studied for the capacity to infect and replicate in human macrophages in vitro. Cultures of human peripheral blood mononuclear cells and phagocytic human leukemic cell line THP-1 cells were infected with each MAH isolate and intracellular colony-forming units (CFU) were determined. At 2 h after infection, i.e., immediately after cell entry, the numbers of intracellular bacteria did not differ between Mav-A and Mav-B organisms in both phagocytic cell types. At 5 days, Mav-A organisms, sharing highly related VNTR-MIRU genotypes, yielded numbers of intracellular CFUs significantly higher than Mav-B organisms in both phagocytic cell types. MIRU-VNTR-based minimum spanning tree analysis of the MAH isolates showed a divergent phylogenetic pathway of Mav-A and Mav-B organisms. Mav-A and Mav-B sequevars might have evolved different pathogenetic properties that might account for their association with different human infections.

Characteristic microglial features in patients with hereditary diffuse leukoencephalopathy with spheroids caused by mutations of the gene encoding the colony stimulating factor-1 receptor

Background: Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an autosomal-dominant dementing disorder. A gene encoding the colony stimulating factor-1 receptor (CSF-1R) has been identified as the causative gene of HDLS. CSF-1R is a crucial regulator of mononuclear phagocytic cells, and expressed predominantly in microglia in CNS.

EFFECTS OF SUPPLEMENTAL FEEDING WITH SOME MEDICINAL PLANTS ON SEMEN CHARACTERISTICS, BLOOD METABOLITES AND HISTOLOGY OF SELECTED ORGANS OF NEW ZELAND MALE RABBITS IN NORTH SINAI

Twenty five New Zealand White (NZW) rabbit bucks, (aged 9 months and weighed 3.28± 0.1kg) were divided randomly into five comparable groups (5 each).Rabbits in the 1st group were fed pelleted control dietwithout medicinal plants (CO), while those in the 2nd, 3rd, 4th and 5th groups were fed ­the pelleted diet containing 3% rosemary (RS), 3% marjoram (MR), 1.5% ginger root (ZR) and 2.5% mixture (MX) of these medicinal plants, respectively. Results showed that rabbit bucks of the ZR group had lower (P<0.05) blood glucose level compared with the control, but did not differ significantly from the other treatments. Serum total protein increased (P<0.05) in RS, MR and MX when compared with control group, but ZR did not differ significantly from the control. Mean concentrations of serum albumin (AL) and AL/GL ratio did not differ significantly due to treatments. Rabbit fed diets containing rosemary, marjoram, ginger or their mixture showed lower (P<0.05) concentrations of plasma triglycerides than those fed the control diet. Rabbit fed ZR and MX had the lowest (P<0.05) level of cholesterol concentration, compared with for CO, RS and MR groups. Serum testosterone levels were significantly (P≤0.05) higher in rabbit bucks of ZR and MX groups compared with CO, RS and MR, respectively.Semen Ejaculate volume was significantly higher in MR, ZR and MX groups compared with the control but RS group did not differ significantly from the control. Means of mass motility were higher (P≤0.05) in treatment groups of RS, ZR and MX than the control but MR group did not differ from the control. The effect of dietary treatment on sperm cell concentration was significant. The ZR group had the highest mean followed by MX, RS, CO and MR groups. The histological examination of testicular sections showed that the elongated spermatids were more apparent in the ZR group and Leyding cells were well-developed in the MX group. The histological examination of liver sections showed marked increase in the size and number of bile ducts and many bi-nucleated hepatocytes and sinusoidal dilatation appeared in RS group. MR group showed an increase in the number of bile ducts, mononuclear phagocytic cells and sinusoid dilatation was observed. ZR group showed a lymphocytic infiltration was surrounding the bile duct and increase in the number of Kupffer cells. In MX group no magnificent changes were observed except that dilatation of the bile duct also no change in the sinusoidal size was observed. The histological examination of kidney sections of different experimental groups showed a congestion of some blood vessels in the MR, ZR and MX groups. Conclusively, the medicinal plants, Rosemary (Rosmarinus officinalis), Marjoram (Origanum majorana), Ginger root (Zingiber officinale) and their mixture could be added to NZW rabbit diets within the limits recorded in this study to improve semen characteristics and reproductive performance of NZW rabbit bucks without any detrimental effects on their health.

Expression of the TNF-family cytokine TL1A (TNFSF15) by renal CX3CR1+ resident mononuclear phagocytic cells and role of TL1A in autoimmune nephritis

Abstract Systemic lupus erythematosus is a polygenic autoimmune disease with a broad spectrum of clinical manifestations including organ-threatening kidney inflammation associated with immune complex (IC) deposition. The kidney is populated by a rich network of tissue-resident mononuclear phagocytes that express Fc receptors (FcRs) and internalize ICs. TL1A (TNFSF15) is a tumor necrosis factor (TNF) superfamily cytokine that can be induced in myeloid cells following ligation of TLR’s and FcRs by IgG IC’s and co-stimulates T cells through its receptor DR3. We have found that DR3 deficiency protects MRL/lpr lupus-prone mice from the renal inflammation but not systemic autoimmunity that develops in these mice, suggesting that TL1A/DR3 interactions could play a role in activating autoimmune T cells and antigen presentation in the kidney. We identified four distinct populations of renal phagocytes based on the expression of F4/80 and CD11b. One population of cells constitutively expressed high levels of surface class II and the CD28 ligand B7-2(CD86), suggesting that they would be potent antigen presenting cells. A fifth population expressing similar markers was present only in inflamed kidneys, both in the MRL/lpr mouse model of lupus and nephrotoxic serum-induced nephritis. Both of these populations constitutively expressed surface TL1A. The new population increases with the severity of nephritis and is unequally distributed between the cortex and the medulla. We will further analyze these populations via transcriptomics and functional assays after immune complex stimulation. This work identifies CX3CR1+ MNP’s as possible antigen-presenting cells in the kidney and a source of TL1A for costimulation of autoreactive T cells in nephritis.