2.Complement genetics, deficiencies, and disease associations.
Protein & Cell 2012;3(7):487-496
The complement system is a key component of innate immunity. More than 45 genes encoding the proteins of complement components or their isotypes and subunits, receptors, and regulators have been discovered. These genes are distributed throughout different chromosomes, with 19 genes comprising three significant complement gene clusters in the human genome. Genetic deficiency of any early component of the classical pathway (C1q, C1r/s, C2, C4, and C3) is associated with autoimmune diseases due to the failure of clearance of immune complexes (IC) and apoptotic materials, and the impairment of normal humoral response. Deficiencies of mannan-binding lectin (MBL) and the early components of the alternative (factor D, properdin) and terminal pathways (from C3 onward components: C5, C6, C7, C8, C9) increase susceptibility to infections and their recurrence. While the association of MBL deficiency with a number of autoimmune and infectious disorders has been well established, the effects of the deficiency of other lectin pathway components (ficolins, MASPs) have been less extensively investigated due to our incomplete knowledge of the genetic background of such deficiencies and the functional activity of those components. For complement regulators and receptors, the consequences of their genetic deficiency vary depending on their specific involvement in the regulatory or signalling steps within the complement cascade and beyond. This article reviews current knowledge and concepts about the genetic load of complement component deficiencies and their association with diseases. An integrative presentation of genetic data with the latest updates provides a background to further investigations of the disease association investigations of the complement system from the perspective of systems biology and systems genetics.
Animals
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Complement Activation
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genetics
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Complement System Proteins
;
deficiency
;
genetics
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HLA Antigens
;
genetics
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Humans
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Immunity, Innate
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genetics
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Immunologic Deficiency Syndromes
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genetics
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Lectins
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metabolism
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Multigene Family
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Receptors, Complement
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genetics
3.IgG Fc engineering to modulate antibody effector functions.
Xinhua WANG ; Mary MATHIEU ; Randall J BREZSKI
Protein & Cell 2018;9(1):63-73
Therapeutic monoclonal antibodies are among the most effective biotherapeutics to date. An important aspect of antibodies is their ability to bind antigen while at the same time recruit immune effector functions. The majority of approved recombinant monoclonal antibody therapies are of the human IgG1 subclass, which can engage both humoral and cellular components of the immune system. The wealth of information generated about antibodies has afforded investigators the ability to molecularly engineer antibodies to modulate effector functions. Here, we review various antibody engineering efforts intended to improve efficacy and safety relative to the human IgG isotype. Further, we will discuss proposed mechanisms by which engineering approaches led to modified interactions with immune components and provide examples of clinical studies using next generation antibodies.
Animals
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Antibodies, Monoclonal
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metabolism
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Antigens
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metabolism
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Complement System Proteins
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metabolism
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Humans
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Immunoglobulin G
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metabolism
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Protein Engineering
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Receptors, Fc
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metabolism
4.Understanding Metabolomics in Biomedical Research.
Su Jung KIM ; Su Hee KIM ; Ji Hyun KIM ; Shin HWANG ; Hyun Ju YOO
Endocrinology and Metabolism 2016;31(1):7-16
The term "omics" refers to any type of specific study that provides collective information on a biological system. Representative omics includes genomics, proteomics, and metabolomics, and new omics is constantly being added, such as lipidomics or glycomics. Each omics technique is crucial to the understanding of various biological systems and complements the information provided by the other approaches. The main strengths of metabolomics are that metabolites are closely related to the phenotypes of living organisms and provide information on biochemical activities by reflecting the substrates and products of cellular metabolism. The transcriptome does not always correlate with the proteome, and the translated proteome might not be functionally active. Therefore, their changes do not always result in phenotypic alterations. Unlike the genome or proteome, the metabolome is often called the molecular phenotype of living organisms and is easily translated into biological conditions and disease states. Here, we review the general strategies of mass spectrometry-based metabolomics. Targeted metabolome or lipidome analysis is discussed, as well as nontargeted approaches, with a brief explanation of the advantages and disadvantages of each platform. Biomedical applications that use mass spectrometry-based metabolomics are briefly introduced.
Complement System Proteins
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Genome
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Genomics
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Glycomics
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Mass Spectrometry
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Metabolism
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Metabolome
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Metabolomics*
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Phenotype
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Proteome
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Proteomics
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Transcriptome
5.Effect of Resveratrol, a SIRT1 Activator, on the Interactions of the CLOCK/BMAL1 Complex.
Insung PARK ; Yool LEE ; Hee Dae KIM ; Kyungjin KIM
Endocrinology and Metabolism 2014;29(3):379-387
BACKGROUND: In mammals, the CLOCK/BMAL1 heterodimer is a key transcription factor complex that drives the cyclic expression of clock-controlled genes involved in various physiological functions and behavioral consequences. Recently, a growing number of studies have reported a molecular link between the circadian clock and metabolism. In the present study, we explored the regulatory effects of SIRTUIN1 (SIRT1), an NAD+-dependent deacetylase, on CLOCK/BMAL1-mediated clock gene expression. METHODS: To investigate the interaction between SIRT1 and CLOCK/BMAL1, we conducted bimolecular fluorescence complementation (BiFC) analyses supplemented with immunocytochemistry assays. BiFC experiments employing deletion-specific mutants of BMAL1 were used to elucidate the specific domains that are necessary for the SIRT1-BMAL1 interaction. Additionally, luciferase reporter assays were used to delineate the effects of SIRT1 on circadian gene expression. RESULTS: BiFC analysis revealed that SIRT1 interacted with both CLOCK and BMAL1 in most cell nuclei. As revealed by BiFC assays using various BMAL1 deletion mutants, the PAS-B domain of BMAL1 was essential for interaction with SIRT1. Activation of SIRT1 with resveratrol did not exert any significant change on the interaction with the CLOCK/BMAL1 complex. However, promoter analysis using Per1-Luc and Ebox-Luc reporters showed that SIRT1 significantly downregulated both promoter activities. This inhibitory effect was intensified by treatment with resveratrol, indicating a role for SIRT1 and its activator in CLOCK/BMAL1-mediated transcription of clock genes. CONCLUSION: These results suggest that SIRT1 may form a regulatory complex with CLOCK/BMAL1 that represses clock gene expression, probably via deacetylase activity.
Cell Nucleus
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Circadian Clocks
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Complement System Proteins
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Fluorescence
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Gene Expression
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Immunohistochemistry
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Luciferases
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Mammals
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Metabolism
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Transcription Factors
6.Cyclic AMP and Cyclic AMP-Receptor Protein are Required for Optimal Capsular Polysaccharide Expression.
Hyeon Kyu CHO ; Sung Heui SHIN
Journal of Bacteriology and Virology 2015;45(1):26-35
Vibrio vulnificus causes fatal infections in susceptible individuals. Group 1 capsular polysaccharide (CPS) operon is responsible for CPS expression, which plays an essential role in the pathogenesis of this pathogen. Cyclic AMP (cAMP) and cAMP receptor protein (crp) complex, which responds to glucose availability and functions as a global regulator, has been known to affect CPS production in this pathogen. This study was undertaken to experimentally verify whether cAMP-Crp directly or indirectly affects CPS production. A mutation in cyaA encoding adenylate cyclase, which is required for cAMP biosynthesis, inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing cyaA or by adding exogenous cAMP. A mutation in crp encoding Crp also inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing crp. Moreover, the crp or cyaA mutation decreased the susceptibility of V. vulnificus against NaOCl. The crp mutation reduced the transcription levels of group 1 CPS operon on a per cell basis. Glucose addition in the absence of Crp stimulated V. vulnificus growth, changed translucent colonies to opaque colonies, and increased the transcription levels of group 1 CPS operon. These results indicate that cAMP or Crp is indirectly involved in optimal CPS production by positively affecting metabolism or V. vulnificus growth rather than by directly controlling the expression of group 1 CPS operon.
Adenylyl Cyclases
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Complement System Proteins
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Cyclic AMP Receptor Protein
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Cyclic AMP*
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Glucose
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Metabolism
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Operon
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Vibrio vulnificus
7.Some influence factors in determination of serum enzyme in hepatitis patients.
Chinese Journal of Experimental and Clinical Virology 2008;22(5):385-387
OBJECTIVETo study some factors (temperature, time, anticoagulate, reagent, apparatus) which influence the detection of serum enzyme.
METHODSSerums obtained from same patient are determined in different conditions. Compare the statistical difference among each group.
RESULTSThe anticoagulant-heparinize Li influence the determination of ADA and CH50. If serums were sent in room temperature for 24 hours, the results will be different. Using regents from different factories will receive different results.
CONCLUSIONDifferent conditions and reagents will influence results. To obtain correct data, we must institute and perform standard regulation.
Adenosine Deaminase ; metabolism ; Blood Specimen Collection ; Complement Hemolytic Activity Assay ; Complement System Proteins ; metabolism ; Equipment and Supplies ; Hepatitis ; blood ; enzymology ; Humans ; Indicators and Reagents ; Male ; Serum ; enzymology ; Specimen Handling ; Temperature
8.Disturbance of the Glutamatergic System in Mood Disorders.
Chansoo JUN ; Yera CHOI ; Soo Mee LIM ; Sujin BAE ; Young Sun HONG ; Jieun E. KIM ; In Kyoon LYOO
Experimental Neurobiology 2014;23(1):28-35
The role of glutamatergic system in the neurobiology of mood disorders draws increasing attention, as disturbance of this system is consistently implicated in mood disorders including major depressive disorder and bipolar disorder. Thus, the glutamate hypothesis of mood disorders is expected to complement and improve the prevailing monoamine hypothesis, and may indicate novel therapeutic targets. Since the contribution of astrocytes is found to be crucial not only in the modulation of the glutamatergic system but also in the maintenance of brain energy metabolism, alterations in the astrocytic function and neuroenergetic environment are suggested as the potential neurobiological underpinnings of mood disorders. In the present review, the evidence of glutamatergic abnormalities in mood disorders based on postmortem and magnetic resonance spectroscopy (MRS) studies is presented, and disrupted energy metabolism involving astrocytic dysfunction is proposed as the underlying mechanism linking altered energy metabolism, perturbations in the glutamatergic system, and pathogenesis of mood disorders.
Astrocytes
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Bipolar Disorder
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Brain
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Complement System Proteins
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Depressive Disorder, Major
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Energy Metabolism
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Glutamic Acid
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Magnetic Resonance Spectroscopy
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Mood Disorders*
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Neurobiology
9.Changes in humoral immunity in sensitized guinea pigs exposed to trichloroethylene.
Qi-xing ZHU ; Hui XU ; Jing LENG ; Tong SHEN
Chinese Journal of Industrial Hygiene and Occupational Diseases 2012;30(9):641-644
OBJECTIVETo study the changes of serum complement C and immunoglobulin (Ig) in sensitized guinea pigs exposed to trichloroethylene.
METHODSThirty six white female guinea pigs (250 ∼ 300 g) were randomly divided into blank control group (5 guinea pig), solvent (olive oil) control group (5 guinea pig) and TCE treatment group (26 guinea pig). According to guinea pig maximization test (GPMT), guinea pigs were exposed to TCE. After stimulating contact for 24 h, the skin reactions of guinea pig back test area were recorded and scored. According to Skin sensitization integral, the guinea pigs treated with TCE were divided into the sensitized group (score ≥ 1) and un-sensitized group (score 0). The concentrations of serum C3, C4, IgA, IgG and IgM were detected in 24 and 72 h, respectively after the experiment.
RESULTSThe sensitization rates of group treated by TCE was 65.38%. The serum C3 levels of groups sensitized to TCE for 24 and 73h were 99.75 ± 1.45 and 93.28 ± 3.61g/ml, respectively, which were significantly lower than that (112.30 ± 9.10 g/ml) of solvent control group (P < 0.05). Also The serum C4 levels of groups sensitized to TCE for 24 and 73 h were 34.63 ± 2.53 and 33.82 ± 2.76g/ml, respectively, which were significantly lower than that (43.87 ± 3.65 g/ml) of solvent control group (P < 0.05). The serum IgA and IgM levels of groups sensitized to TCE and unsensitized to TCE for 24 and 72 h were significantly lower than those of solvent group (P < 0.05). as compared with unsensitized groups, the serum IgA levels of the groups sensitized to TCE for 24 and 72 h significantly decreased (P < 0.05).
CONCLUSIONAfter the guinea pig skin was sensitized to TCE, the serum C3, C4 levels decreased, the immune function disordered.
Animals ; Complement System Proteins ; metabolism ; Female ; Guinea Pigs ; Immunity, Humoral ; drug effects ; Immunoglobulins ; blood ; Skin ; drug effects ; Trichloroethylene ; toxicity
10.Research advances in immunological pathogenesis of immunoglobulin A vasculitis.
Chinese Journal of Contemporary Pediatrics 2017;19(7):837-840
Immunoglobulin A (IgA) vasculitis is the most common leukocytoclastic small-vessel vasculitis in children and mainly involves the small vessels in the skin, joints, digestive tract, and kidneys. Its pathogenesis is still unclear. Currently, it is believed that environmental factors can cause autoimmune dysfunction and lead to the deposition of IgA-containing immune complexes on the wall of arterioles on the basis of genetic factors. This article reviews the research advances in the role of immune factors in the pathogenesis of IgA vasculitis.
Autoantibodies
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analysis
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Complement System Proteins
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physiology
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Cytokines
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physiology
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Glycosylation
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Humans
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Immunoglobulin A
;
analysis
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Immunoglobulin E
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metabolism
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Vasculitis
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etiology
;
immunology