8 research outputs found

    PRRDB: A comprehensive database of Pattern-Recognition Receptors and their ligands

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    <p>Abstract</p> <p>Background</p> <p>Recently in a number of studies, it has been demonstrated that the innate immune system doesn't merely acts as the first line of defense but provides critical signals for the development of specific adaptive immune response. Innate immune system employs a set of receptors called pattern recognition receptors (PRRs) that recognize evolutionarily conserved patterns from pathogens called pathogen associated molecular patterns (PAMPs). In order to assist scientific community, a database PRRDB has been developed that provides extensive information about pattern recognition receptors and their ligands.</p> <p>Results</p> <p>The current version of database contains around 500 patterns recognizing receptors from 77 distinct organisms ranging from insects to human. This includes 177 Toll-like receptors, 124 are Scavenger receptors and 67 are Nucleotide Binding Site-Leucine repeats rich receptors. The database also provides information about 266 ligands that includes carbohydrates, proteins, nucleic acids, glycolipids, glycoproteins, lipopeptides. A number of web tools have been integrated in PRRDB in order to provide following services: i) searching on any field; ii) database browsing; and iii) BLAST search against the pattern-recognition receptors. PRRDB also provides external links to standard databases like Swiss-Prot and Pubmed.</p> <p>Conclusion</p> <p>PRRDB is a unique database of its kind, which provides comprehensive information about innate immunity. This database will be very useful in designing effective adjuvant for subunit vaccine and in understanding role of innate immunity. The database is available from the URL's in the Availabiltiy and requirements section.</p

    Hmrbase: a database of hormones and their receptors

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    <p>Abstract</p> <p>Background</p> <p>Hormones are signaling molecules that play vital roles in various life processes, like growth and differentiation, physiology, and reproduction. These molecules are mostly secreted by endocrine glands, and transported to target organs through the bloodstream. Deficient, or excessive, levels of hormones are associated with several diseases such as cancer, osteoporosis, diabetes etc. Thus, it is important to collect and compile information about hormones and their receptors.</p> <p>Description</p> <p>This manuscript describes a database called Hmrbase which has been developed for managing information about hormones and their receptors. It is a highly curated database for which information has been collected from the literature and the public databases. The current version of Hmrbase contains comprehensive information about ~2000 hormones, e.g., about their function, source organism, receptors, mature sequences, structures etc. Hmrbase also contains information about ~3000 hormone receptors, in terms of amino acid sequences, subcellular localizations, ligands, and post-translational modifications etc. One of the major features of this database is that it provides data about ~4100 hormone-receptor pairs. A number of online tools have been integrated into the database, to provide the facilities like keyword search, structure-based search, mapping of a given peptide(s) on the hormone/receptor sequence, sequence similarity search. This database also provides a number of external links to other resources/databases in order to help in the retrieving of further related information.</p> <p>Conclusion</p> <p>Owing to the high impact of endocrine research in the biomedical sciences, the Hmrbase could become a leading data portal for researchers. The salient features of Hmrbase are hormone-receptor pair-related information, mapping of peptide stretches on the protein sequences of hormones and receptors, Pfam domain annotations, categorical browsing options, online data submission, DrugPedia linkage etc. Hmrbase is available online for public from <url>http://crdd.osdd.net/raghava/hmrbase/</url>.</p

    Transcriptome profiling of immune rejection mechanisms in a porcine vascularized composite allotransplantation model

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    BackgroundVascularized composite allotransplantation (VCA) offers the potential for a biological, functional reconstruction in individuals with limb loss or facial disfigurement. Yet, it faces substantial challenges due to heightened immune rejection rates compared to solid organ transplants. A deep understanding of the genetic and immunological drivers of VCA rejection is essential to improve VCA outcomesMethodsHeterotopic porcine hindlimb VCA models were established and followed until reaching the endpoint. Skin and muscle samples were obtained from VCA transplant recipient pigs for histological assessments and RNA sequencing analysis. The rejection groups included recipients with moderate pathological rejection, treated locally with tacrolimus encapsulated in triglycerol-monostearate gel (TGMS-TAC), as well as recipients with severe end-stage rejection presenting evident necrosis. Healthy donor tissue served as controls. Bioinformatics analysis, immunofluorescence, and electron microscopy were utilized to examine gene expression patterns and the expression of immune response markers.ResultsOur comprehensive analyses encompassed differentially expressed genes, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathways, spanning various composite tissues including skin and muscle, in comparison to the healthy control group. The analysis revealed a consistency and reproducibility in alignment with the pathological rejection grading. Genes and pathways associated with innate immunity, notably pattern recognition receptors (PRRs), damage-associated molecular patterns (DAMPs), and antigen processing and presentation pathways, exhibited upregulation in the VCA rejection groups compared to the healthy controls. Our investigation identified significant shifts in gene expression related to cytokines, chemokines, complement pathways, and diverse immune cell types, with CD8 T cells and macrophages notably enriched in the VCA rejection tissues. Mechanisms of cell death, such as apoptosis, necroptosis and ferroptosis were observed and coexisted in rejected tissues.ConclusionOur study provides insights into the genetic profile of tissue rejection in the porcine VCA model. We comprehensively analyze the molecular landscape of immune rejection mechanisms, from innate immunity activation to critical stages such as antigen recognition, cytotoxic rejection, and cell death. This research advances our understanding of graft rejection mechanisms and offers potential for improving diagnostic and therapeutic strategies to enhance the long-term success of VCA

    Development and Screening of a Marker to Detect Activated Rainbow Trout Leukocytes

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    Monoclonal antibodies (mAbs) have been essential tools in the elucidation of the immune system of mammals, and their application to identify surface molecules on leukocytes have allowed important functions of these cell to be identified (such as receptors that bind antigens, ligands involved in cell to cell signaling or in initiating immune response activity). Not only have mAbs been used to discriminate cells during different stages of cell development, but have also assisted in understanding the dynamics of molecules expressed during functional processes. Such molecules detected on human leukocytes are called human leukocyte differentiation antigens or HLDA. In order to group the antibodies that detect similar molecules and have similar patterns of reaction, immunologists have organised the mAbs that bind to these antigens into Clusters of Differentiation (CD). So far, there are about 350 leukocyte surface molecules detected by mAbs with a CD nomenclature for human leukocytes (www.hcdm.org). In fish immunology there is a great need to produce mAbs that are able to differentiate the various components of the fish immune system to assist in the elucidation of the fish immune system. The present study was an endeavour to develop and characterise mAbs that could be accredited to such scheme. A better understanding of the fish immune system is urgently required so that effective strategies of control can be developed for significant diseases during fish farming. Monoclonal antibodies were prepared by immunizing mice with thymic leukocytes from rainbow trout. The leukocytes were activated with the lectin Concanavalin A to promote the activation and proliferation of the target T-cell population. The selection of clones producing antibodies during screening was performed on the basis of the response of the supernatant from hybridomas using three consecutive assays. First, selection was determined by the positive staining of cells from the thymus in a Dot blot assay. Secondary screening was performed by means of flow cytometry (FCM) and the criterion for selection was the preferential detection of leukocytes gated in the lymphocyte region. Finally, the positive supernatants from hybridomes were evaluated to determine their effectiveness in the detection of modifications in the labelled cells during a multiple way activation by detection of foreign histocompatibility complex enhanced with mitogens. Monoclonal antibody TcOm15 was selected from 564 hybridomas produced and then used to stain cells from various Rainbow Trout tissues. It was clear from FCM, microscopy and Western blot analysis that mAb TcOm15 not only reacted with thymic cells but also with cells from other tissues. Differential staining of cells with mAb TcOm15 was observed with 27.1 ±1.4 % of leukocytes from peripheral blood leukocytes (PBL) stained in comparison to 2.0 ±0.2 % from the thymus, 13.8 ±0.4 % from the spleen, and 5.6 ±0.6 % cells stained from head kidney. The labeled cells showed characteristics of lymphocytes and monocytes, presenting a distinctive staining in immunohistochemistry and confocal microscopy. Western blot analysis, using electrophoresed proteins under denaturing conditions with leukocytes from several different tissues, showed that mAb TcOm15 did not detect a single protein. At least three proteins appeared to be identified by the mAb at 105, 160 and 200 kDa. The proteins were identified as α Actinin-4, non-erythroid Spectrin αII chain or Ig-like protein and non-muscle Myosin (MYH10) by MALDI-TOF analysis. Three of these identities are for compositional molecules for the cytoskeleton of different types of cells, and one it is associated to immunoglobulin superfamily. The identification of these proteins by mAb TcOm15 suggests an ability of this mAb to detect a specific function, possibly related with the synchronicity of expression or interaction of cytoskeleton-membrane proteins forming a multiprotein complex. Another possibility is as a carrier role for a protein during interactions. Colocalization of the mAb with F actin from the cytoskeleton was also observed suggesting the possibility that mAb TcOm15 detects a specific site in a multi-protein complex from the cytoskeleton. The molecule detected showed down-regulation in a dose dependant way with Concanavalin A and the expression was almost lost following stimulation of cells with phorbol 12-myristate 13-acetate stimulation. Leukocytes from the PBL and thymus up-regulated the expression of the TcOm15 molecule under mitogenic conditions in vitro, and results from in vivo experiments suggested the possibility of up-regulation on thymic cells. In conclusion, the results obtained in the present study provide information on a potentially useful marker (mAb TcOm15) for a cytoskeleton-membrane antigen that is modulated during stimulation of teleost lymphocytes. Additionally, this may enable insights into the relationship between cytoskeletal proteins and membrane associated immunoglobulin. Future research is necessary in order to explain this relationship and to determine the functional participation of the TcOm15 molecule during the activation of rainbow trout cells

    Antimicrobial activities of phenoloxidasegenerated reactive compounds and regulation of immune response by a serpin from Manduca sexta

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    Scope and Method of Study: Phenoloxidase (PO) and its activation system are implicated in several defense responses of insects. Upon wounding or infection, inactive prophenoloxidase (proPO) is converted to active PO through a network of serine proteases and their homologs. PO generates reactive compounds such as 5,6- dihydroxyindole (DHI), which have a broad-spectrum antimicrobial activity. The regulation of proteolytic activation cascade of immune response involves serine protease inhibitor (serpin) family molecules. Many serpins are found to play key roles in negatively regulating immune defense system through irreversibly inhibiting target serine proteases, not only to humoral but also to the cellular responses. A new gene, serpin-10, was found in Manduca sexta and expressed in insect cell via infection of recombinant baculovirus contain serpin-10 cDNA fragment. The serpin10 antiserum was prepared and used for determining protein level in hemolymph and affinity chromatography to analysis immune complex formation with serpin-10.Findings and Conclusions: Here we demonstrate that DHI and its spontaneous oxidation products are active against bacteria, fungi, viruses, and parasitic wasp eggs. These results established that proPO activation is an integral component of the insect defense system. A possible mechanism of DHI toxicity is the cross-linking of proteins and nucleic acid via its oxidization products. The transcript level of M. sexta serpin-10 is higher in nerve system, trachea, and fat body than in other tissues. The transcriptional level does not change a lot during 4th and 5th instar larval stages, but decreases remarkably in middle and late pupa stage, and then recovers in adults. This gene is suppressed in fat body, which indicates it may have a relationship with immune response to pathogen invasion. The protein level of serpin-10 is quite stable in hemolymph. M. sexta serpin10 forms a covalent complex with an unknown serine protease. HP1 is present in the immune complex via non-covalent association

    Development and screening of a marker to detect activated rainbow trout leukocytes

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    Monoclonal antibodies (mAbs) have been essential tools in the elucidation of the immune system of mammals, and their application to identify surface molecules on leukocytes have allowed important functions of these cell to be identified (such as receptors that bind antigens, ligands involved in cell to cell signaling or in initiating immune response activity). Not only have mAbs been used to discriminate cells during different stages of cell development, but have also assisted in understanding the dynamics of molecules expressed during functional processes. Such molecules detected on human leukocytes are called human leukocyte differentiation antigens or HLDA. In order to group the antibodies that detect similar molecules and have similar patterns of reaction, immunologists have organised the mAbs that bind to these antigens into Clusters of Differentiation (CD). So far, there are about 350 leukocyte surface molecules detected by mAbs with a CD nomenclature for human leukocytes (www.hcdm.org). In fish immunology there is a great need to produce mAbs that are able to differentiate the various components of the fish immune system to assist in the elucidation of the fish immune system. The present study was an endeavour to develop and characterise mAbs that could be accredited to such scheme. A better understanding of the fish immune system is urgently required so that effective strategies of control can be developed for significant diseases during fish farming. Monoclonal antibodies were prepared by immunizing mice with thymic leukocytes from rainbow trout. The leukocytes were activated with the lectin Concanavalin A to promote the activation and proliferation of the target T-cell population. The selection of clones producing antibodies during screening was performed on the basis of the response of the supernatant from hybridomas using three consecutive assays. First, selection was determined by the positive staining of cells from the thymus in a Dot blot assay. Secondary screening was performed by means of flow cytometry (FCM) and the criterion for selection was the preferential detection of leukocytes gated in the lymphocyte region. Finally, the positive supernatants from hybridomes were evaluated to determine their effectiveness in the detection of modifications in the labelled cells during a multiple way activation by detection of foreign histocompatibility complex enhanced with mitogens. Monoclonal antibody TcOm15 was selected from 564 hybridomas produced and then used to stain cells from various Rainbow Trout tissues. It was clear from FCM, microscopy and Western blot analysis that mAb TcOm15 not only reacted with thymic cells but also with cells from other tissues. Differential staining of cells with mAb TcOm15 was observed with 27.1 ±1.4 % of leukocytes from peripheral blood leukocytes (PBL) stained in comparison to 2.0 ±0.2 % from the thymus, 13.8 ±0.4 % from the spleen, and 5.6 ±0.6 % cells stained from head kidney. The labeled cells showed characteristics of lymphocytes and monocytes, presenting a distinctive staining in immunohistochemistry and confocal microscopy. Western blot analysis, using electrophoresed proteins under denaturing conditions with leukocytes from several different tissues, showed that mAb TcOm15 did not detect a single protein. At least three proteins appeared to be identified by the mAb at 105, 160 and 200 kDa. The proteins were identified as α Actinin-4, non-erythroid Spectrin αII chain or Ig-like protein and non-muscle Myosin (MYH10) by MALDI-TOF analysis. Three of these identities are for compositional molecules for the cytoskeleton of different types of cells, and one it is associated to immunoglobulin superfamily. The identification of these proteins by mAb TcOm15 suggests an ability of this mAb to detect a specific function, possibly related with the synchronicity of expression or interaction of cytoskeleton-membrane proteins forming a multiprotein complex. Another possibility is as a carrier role for a protein during interactions. Colocalization of the mAb with F actin from the cytoskeleton was also observed suggesting the possibility that mAb TcOm15 detects a specific site in a multi-protein complex from the cytoskeleton. The molecule detected showed down-regulation in a dose dependant way with Concanavalin A and the expression was almost lost following stimulation of cells with phorbol 12-myristate 13-acetate stimulation. Leukocytes from the PBL and thymus up-regulated the expression of the TcOm15 molecule under mitogenic conditions in vitro, and results from in vivo experiments suggested the possibility of up-regulation on thymic cells. In conclusion, the results obtained in the present study provide information on a potentially useful marker (mAb TcOm15) for a cytoskeleton-membrane antigen that is modulated during stimulation of teleost lymphocytes. Additionally, this may enable insights into the relationship between cytoskeletal proteins and membrane associated immunoglobulin. Future research is necessary in order to explain this relationship and to determine the functional participation of the TcOm15 molecule during the activation of rainbow trout cells.EThOS - Electronic Theses Online ServiceCONACYT, MexicoGBUnited Kingdo

    Functional and phenotypical aspects of murine Natural Killer cells in the context of education

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