Gene Symbol: C1QA
Description: complement C1q A chain
Alias: complement C1q subcomponent subunit A, complement C1q chain A, complement component 1, q subcomponent, A chain, complement component 1, q subcomponent, alpha polypeptide, complement component C1q, A chain
Species: human
Products:     C1QA

Top Publications

  1. Roumenina L, Bureeva S, Kantardjiev A, Karlinsky D, Andia Pravdivy J, Sim R, et al. Complement C1q-target proteins recognition is inhibited by electric moment effectors. J Mol Recognit. 2007;20:405-15 pubmed
    ..e. the complement activation signal transmission) will be impaired and the cascade initiation disrupted. These results could serve as a starting point for the exploration of a new form of 'electric moment inhibitors/effectors'. ..
  2. Racila E, Racila D, Ritchie J, Taylor C, Dahle C, Weiner G. The pattern of clinical breast cancer metastasis correlates with a single nucleotide polymorphism in the C1qA component of complement. Immunogenetics. 2006;58:1-8 pubmed
    ..We evaluated if the sole coding polymorphism of C1qA associates with outcome in patients with breast carcinoma...
  3. Leigh L, Ghebrehiwet B, Perera T, Bird I, Strong P, Kishore U, et al. C1q-mediated chemotaxis by human neutrophils: involvement of gClqR and G-protein signalling mechanisms. Biochem J. 1998;330 ( Pt 1):247-54 pubmed
    ..Our results suggests C1q-mediated chemotaxis involves gC1qR as well as G-protein-coupled signal-transduction mechanisms operating downstream to neutrophil chemotaxis. ..
  4. Roumenina L, Ruseva M, Zlatarova A, Ghai R, Kolev M, Olova N, et al. Interaction of C1q with IgG1, C-reactive protein and pentraxin 3: mutational studies using recombinant globular head modules of human C1q A, B, and C chains. Biochemistry. 2006;45:4093-104 pubmed
    ..Thus, a recently proposed model suggesting the rotation of the gC1q domain upon ligand recognition may be extended to C1q interaction with CRP and PTX3 in addition to IgG1. ..
  5. Ghebrehiwet B, Lim B, Peerschke E, Willis A, Reid K. Isolation, cDNA cloning, and overexpression of a 33-kD cell surface glycoprotein that binds to the globular "heads" of C1q. J Exp Med. 1994;179:1809-21 pubmed
    ..abstract truncated at 400 words) ..
  6. Chen G, Tan C, Teh B, Lu J. Molecular mechanisms for synchronized transcription of three complement C1q subunit genes in dendritic cells and macrophages. J Biol Chem. 2011;286:34941-50 pubmed publisher
    ..The three human C1q genes are closely bundled on chromosome 1 (C1qA-C1qC-C1qB) and their basal and IFN?-stimulated expression, largely restricted to macrophages and dendritic cells, ..
  7. Gaboriaud C, Juanhuix J, Gruez A, Lacroix M, Darnault C, Pignol D, et al. The crystal structure of the globular head of complement protein C1q provides a basis for its versatile recognition properties. J Biol Chem. 2003;278:46974-82 pubmed
    ..The C1q/human IgG1 model suggests a critical role for the hinge region of IgG and for the relative orientation of its Fab domain in C1q binding. ..
  8. Martens H, Zuurman M, de Lange A, Nolte I, van der Steege G, Navis G, et al. Analysis of C1q polymorphisms suggests association with systemic lupus erythematosus, serum C1q and CH50 levels and disease severity. Ann Rheum Dis. 2009;68:715-20 pubmed publisher
    ..Polymorphisms of the C1qA gene are associated with low serum C1q levels in patients with cutaneous LE, but C1q polymorphisms have not been ..
  9. Castillo C, Ramirez G, Valck C, Aguilar L, Maldonado I, Rosas C, et al. The interaction of classical complement component C1 with parasite and host calreticulin mediates Trypanosoma cruzi infection of human placenta. PLoS Negl Trop Dis. 2013;7:e2376 pubmed publisher
    ..Approximately 30% of infected individuals develop circulatory or digestive pathology. While in underdeveloped countries transmission is mainly through hematophagous arthropods, transplacental infection prevails in developed ones...

More Information

Publications150 found, 100 shown here

  1. Racila D, Sontheimer C, Sheffield A, Wisnieski J, Racila E, Sontheimer R. Homozygous single nucleotide polymorphism of the complement C1QA gene is associated with decreased levels of C1q in patients with subacute cutaneous lupus erythematosus. Lupus. 2003;12:124-32 pubmed
    ..skin disease, subacute cutaneous lupus erythematosus (SCLE), and a new single nucleotide polymorphism (SNP) in the C1QA gene. We also describe an association between this SNP and lower levels of serum C1q...
  2. Racila E, Link B, Weng W, Witzig T, Ansell S, Maurer M, et al. A polymorphism in the complement component C1qA correlates with prolonged response following rituximab therapy of follicular lymphoma. Clin Cancer Res. 2008;14:6697-703 pubmed publisher
    ..The purpose of this study was to explore the relationship between the C1qA([276]) polymorphism and the clinical response to rituximab in patients with follicular lymphoma.
  3. Ying S, Gewurz A, Jiang H, Gewurz H. Human serum amyloid P component oligomers bind and activate the classical complement pathway via residues 14-26 and 76-92 of the A chain collagen-like region of C1q. J Immunol. 1993;150:169-76 pubmed
    ..Thus, SAP oligomers bind C1q and activate the classical C pathway via the collagen-like region of C1q, at sites located within residues 14-26 and/or 76-92 of the C1q A chain. ..
  4. Stuart G, Lynch N, Day A, Schwaeble W, Sim R. The C1q and collectin binding site within C1q receptor (cell surface calreticulin). Immunopharmacology. 1997;38:73-80 pubmed
    ..The C1q and collection binding site on C1qR/CRT has therefore been localised to the S-domain. ..
  5. Tahtouh M, Garçon Bocquet A, Croq F, Vizioli J, Sautiere P, Van Camp C, et al. Interaction of HmC1q with leech microglial cells: involvement of C1qBP-related molecule in the induction of cell chemotaxis. J Neuroinflammation. 2012;9:37 pubmed publisher
    ..Taken together, these results highlight the importance of the interaction between C1q and C1qBP in microglial activation leading to nerve repair in the medicinal leech. ..
  6. Thanei S, Trendelenburg M. Anti-C1q autoantibodies from patients with systemic lupus erythematosus induce C1q production by macrophages. J Leukoc Biol. 2017;101:481-491 pubmed publisher
    ..In conclusion, our data indicate that imC1q-bound anti-C1q strongly stimulate the C1q production by HMDMs. Anti-C1q-induced C1q secretion might be an important immune-modulatory factor in SLE. ..
  7. Reid K. Isolation, by partial pepsin digestion, of the three collagen-like regions present in subcomponent Clq of the first component of human complement. Biochem J. 1976;155:5-17 pubmed
    ..50% higher than expected from the amino acid sequence data. This is probably due to the high collagen-like sequence content of these fragments. ..
  8. Stoiber H, Thielens N, Ebenbichler C, Arlaud G, Dierich M. The envelope glycoprotein of HIV-1 gp120 and human complement protein C1q bind to the same peptides derived from three different regions of gp41, the transmembrane glycoprotein of HIV-1, and share antigenic homology. Eur J Immunol. 1994;24:294-300 pubmed
    ..These data suggest that in addition to functional homology between C1q and gp120 structural homology between these two molecules exists. This molecular mimicry might become the basis for immunologically relevant autoimmune phenomena. ..
  9. Wang Y, Tong X, Zhang J, Ye X. The complement C1qA enhances retinoic acid-inducible gene-I-mediated immune signalling. Immunology. 2012;136:78-85 pubmed publisher
    ..Here we demonstrate that the complement C1qA interacts with different RIG-I pathway components and enhances RIG-I-VISA-mediated signalling pathway as well as ..
  10. Calton M, Lee D, Sundaresan S, Mendus D, Leu R, Wangsawihardja F, et al. A lack of immune system genes causes loss in high frequency hearing but does not disrupt cochlear synapse maturation in mice. PLoS ONE. 2014;9:e94549 pubmed publisher
    ..the major histocompatibility complex class I (MHCI) genes, H2-K(b) and H2-D(b), and the complement cascade gene, C1qa. Since the mechanisms involved in synaptic refinement in the cochlea are not well understood, we investigated ..
  11. Kalinin S, González Prieto M, Scheiblich H, Lisi L, Kusumo H, Heneka M, et al. Transcriptome analysis of alcohol-treated microglia reveals downregulation of beta amyloid phagocytosis. J Neuroinflammation. 2018;15:141 pubmed publisher
    ..Alcohol also increased several complement-related mRNAs that have roles in phagocytosis, including C1qa, b, and c; C3; and C3aR1...
  12. Bozzini S, Falcone V, Conaldi P, Visai L, Biancone L, Dolei A, et al. Heparin-binding domain of human fibronectin binds HIV-1 gp120/160 and reduces virus infectivity. J Med Virol. 1998;54:44-53 pubmed
    ..Thus, Fn that is present in plasma and mucinous secretions may well affect HIV infectivity and virus distribution in vivo. ..
  13. Wang J, Ma S, Tao R, Xia L, Liu L, Jiang Y. Gene expression profile changes in rat dorsal horn after sciatic nerve injury. Neurol Res. 2017;39:176-182 pubmed publisher
    ..g. ILF3 and LYVE1); and 41 were common in both two groups (e.g. FCER1G, C1QA, C1QB and C1QC)...
  14. Turbica I, Gallais Y, Gueguen C, Tharinger H, Al Sabbagh C, Gorges R, et al. Ectosomes from neutrophil-like cells down-regulate nickel-induced dendritic cell maturation and promote Th2 polarization. J Leukoc Biol. 2015;97:737-49 pubmed publisher
    ..However, no increase in pan-regulatory DC marker genes (GILZ, CATC, C1QA) was observed; rather, levels of effector DC markers (Mx1, NMES1) were increased...
  15. Röszer T. Transcriptional control of apoptotic cell clearance by macrophage nuclear receptors. Apoptosis. 2017;22:284-294 pubmed publisher
    ..transcriptional control of key genes of apoptotic cell recognition and internalization, such as Cd36, Mertk, Axl, C1qa, Tgm2, Abca1...
  16. Sellar G, Cockburn D, Reid K. Localization of the gene cluster encoding the A, B, and C chains of human C1q to 1p34.1-1p36.3. Immunogenetics. 1992;35:214-6 pubmed
  17. Sellar G, Blake D, Reid K. Characterization and organization of the genes encoding the A-, B- and C-chains of human complement subcomponent C1q. The complete derived amino acid sequence of human C1q. Biochem J. 1991;274 ( Pt 2):481-90 pubmed
  18. Thielens N, Tacnet Delorme P, Arlaud G. Interaction of C1q and mannan-binding lectin with viruses. Immunobiology. 2002;205:563-74 pubmed
    ..These interactions lead to virus inactivation, are independent of complement activation and are influenced by the oligomerization state of the collectin. ..
  19. Sjöberg A, Nyström S, Hammarstrom P, Blom A. Native, amyloid fibrils and beta-oligomers of the C-terminal domain of human prion protein display differential activation of complement and bind C1q, factor H and C4b-binding protein directly. Mol Immunol. 2008;45:3213-21 pubmed publisher
    ..Taken together the present study indicates that complement activation may be an important factor in human prion diseases, suggesting that complement induced activities may prove relevant therapeutic targets. ..
  20. Carlucci F, Ishaque A, Ling G, Szajna M, Sandison A, Donatien P, et al. C1q Modulates the Response to TLR7 Stimulation by Pristane-Primed Macrophages: Implications for Pristane-Induced Lupus. J Immunol. 2016;196:1488-94 pubmed publisher
    ..In this study, we explored whether C1q deficiency could affect pristane-induced lupus. Surprisingly, C1qa(-/-) mice developed lower titers of circulating Abs and milder arthritis compared with the controls...
  21. Chen M, Ding M, Li Y, Zhong X, Liu S, Guo Z, et al. The complement component 1 q (C1q) in Nile tilapia (Oreochromis niloticus): Functional characterization in host defense against bacterial infection and effect on cytokine response in macrophages. Dev Comp Immunol. 2018;87:98-108 pubmed publisher
    ..In this study, the full-length of C1q subcomponent A, B and C chain genes (C1qA, C1qB and C1qC) were identified and characterized from Nile tilapia (Oreochromis niloticus)...
  22. Kojouharova M, Gadjeva M, Tsacheva I, Zlatarova A, Roumenina L, Tchorbadjieva M, et al. Mutational analyses of the recombinant globular regions of human C1q A, B, and C chains suggest an essential role for arginine and histidine residues in the C1q-IgG interaction. J Immunol. 2004;172:4351-8 pubmed
  23. Xue Q, Gu C, Rivera J, Hook M, Chen X, Pozzi A, et al. Entry of Bacillus anthracis spores into epithelial cells is mediated by the spore surface protein BclA, integrin ?2?1 and complement component C1q. Cell Microbiol. 2011;13:620-34 pubmed publisher
    ..These findings suggest a novel mechanism for pathogen entry into host cells as well as a new function for C1q-integrin interactions. The implications of these findings are discussed. ..
  24. Kouser L, Madhukaran S, Shastri A, Saraon A, Ferluga J, Al Mozaini M, et al. Emerging and Novel Functions of Complement Protein C1q. Front Immunol. 2015;6:317 pubmed publisher
    ..C1q role in synaptic pruning, and thus CNS development, its anti-cancer effects as an immune surveillance molecule, and possibly in aging are currently areas of extensive research. ..
  25. Jiao H, Rutar M, Fernando N, Yednock T, Sankaranarayanan S, Aggio Bruce R, et al. Subretinal macrophages produce classical complement activator C1q leading to the progression of focal retinal degeneration. Mol Neurodegener. 2018;13:45 pubmed publisher
    ..Wild-type (WT), C1qa knockout (C1qa-/-) and mice treated with a C1q inhibitor (ANX-M1; Annexon Biosciences), were exposed to ..
  26. Thielens N, Bally I, Ebenbichler C, Dierich M, Arlaud G. Further characterization of the interaction between the C1q subcomponent of human C1 and the transmembrane envelope glycoprotein gp41 of HIV-1. J Immunol. 1993;151:6583-92 pubmed
  27. Terrasse R, Tacnet Delorme P, Moriscot C, Perard J, Schoehn G, Vernet T, et al. Human and pneumococcal cell surface glyceraldehyde-3-phosphate dehydrogenase (GAPDH) proteins are both ligands of human C1q protein. J Biol Chem. 2012;287:42620-33 pubmed publisher
    ..This ability of C1q to sense both human and bacterial GAPDHs sheds new insights on the role of this important defense collagen molecule in modulating the immune response. ..
  28. Jlajla H, Sellami M, Sfar I, Laadhar L, Zerzeri Y, Abdelmoula M, et al. New C1q mutation in a Tunisian family. Immunobiology. 2014;219:241-6 pubmed publisher
    ..Amongst the other 14 mutations leading to C1qD, g.5580G4C represents the first reported transversion leading to human C1qD. ..
  29. Shimizu S, Tanaka Y, Tazawa H, Verma S, Onoe T, Ishiyama K, et al. Fc-Gamma Receptor Polymorphisms Predispose Patients to Infectious Complications After Liver Transplantation. Am J Transplant. 2016;16:625-33 pubmed publisher
    ..The single-nucleotide polymorphisms (SNPs) of C1QA [276A/G], FCGR2A [131H/R], and FCGR3A [158F/V], genes encoding the Fc gamma receptor (FcγR), were analyzed in 89 ..
  30. Kraft A, McPherson C, Harry G. Association Between Microglia, Inflammatory Factors, and Complement with Loss of Hippocampal Mossy Fiber Synapses Induced by Trimethyltin. Neurotox Res. 2016;30:53-66 pubmed publisher
    ..At 2 days, C1q protein was evident in the CA3 with elevated C1qa, C1qb, C3, Cr3a, and Cr3b mRNA levels...
  31. Bartling B, Niemann K, Pliquett R, Treede H, Simm A. Altered gene expression pattern indicates the differential regulation of the immune response system as an important factor in cardiac aging. Exp Gerontol. 2019;117:13-20 pubmed publisher
    ..such as chemokines (CCLs 6, 8, 9), proteins of the S100 family (S100s 4, 8, 9, 10, 11), complement components (C1qa, C1qb, C1qc, C3, C4b), bacteria/virus-induced genes (lysozyme 1/2, interferon-activated genes), and pro-..
  32. Du H, Shi J, Wang M, An S, Guo X, Wang Z. Analyses of gene expression profiles in the rat dorsal horn of the spinal cord using RNA sequencing in chronic constriction injury rats. J Neuroinflammation. 2018;15:280 pubmed publisher
    ..PPI network analysis showed that Cd68, C1qc, C1qa, Laptm5, and Fcgr3a were crucial nodes with high connectivity degrees...
  33. Zhang J, Li G, Liu X, Wang Z, Liu W, Ye X. Influenza A virus M1 blocks the classical complement pathway through interacting with C1qA. J Gen Virol. 2009;90:2751-8 pubmed publisher
    ..This study demonstrated that M1 is able to interact with complement C1qA and plays an important inhibitory function in the classical complement pathway...
  34. Sumida T, Naito A, Nomura S, Nakagawa A, Higo T, Hashimoto A, et al. Complement C1q-induced activation of β-catenin signalling causes hypertensive arterial remodelling. Nat Commun. 2015;6:6241 pubmed publisher
    ..Macrophage depletion and C1qa gene deletion attenuated the hypertension-induced β-catenin signalling, proliferation of VSMCs and pathological ..
  35. Cheow E, Cheng W, Lee C, de Kleijn D, Sorokin V, Sze S. Plasma-derived Extracellular Vesicles Contain Predictive Biomarkers and Potential Therapeutic Targets for Myocardial Ischemic (MI) Injury. Mol Cell Proteomics. 2016;15:2628-40 pubmed publisher
    ..for clinical applications; these reflected post-infarct pathways of complement activation (Complement C1q subcomponent subunit A (C1QA), 3.23-fold change, p = 0.012; Complement C5 (C5), 1.27-fold change, p = 0...
  36. Das L, Ide K, Tanaka A, Morimoto H, Shimizu S, Tanimine N, et al. Fc-gamma receptor 3A polymorphism predicts the incidence of urinary tract infection in kidney-transplant recipients. Hum Immunol. 2017;78:357-362 pubmed publisher
    ..The single-nucleotide polymorphisms (SNPs) of C1QA [276 A/G], FCGR2A [131 H/R], and FCGR3A [158 F/V], genes encoding the Fc gamma receptor (Fc?R), were analyzed in 81 ..
  37. Haure Mirande J, Wang M, Audrain M, Fanutza T, Kim S, Heja S, et al. Integrative approach to sporadic Alzheimer's disease: deficiency of TYROBP in cerebral Aβ amyloidosis mouse normalizes clinical phenotype and complement subnetwork molecular pathology without reducing Aβ burden. Mol Psychiatry. 2019;24:431-446 pubmed publisher
    ..in the switch from homeostatic microglia to disease-associated microglia (DAM), including Trem2, complement (C1qa, C1qb, C1qc, and Itgax), Clec7a and Cst7...
  38. Cao C, Li P, Luan H, Chen W, Li C, Hu C, et al. Association study of C1qA polymorphisms with systemic lupus erythematosus in a Han population. Lupus. 2012;21:502-7 pubmed publisher
    The aim of this study was to evaluate the association of single nucleotide polymorphisms (SNPs) in the C1qA gene region with systemic lupus erythematosus (SLE) in a Chinese Han population...
  39. van Schaarenburg R, Daha N, Schonkeren J, Nivine Levarht E, van Gijlswijk Janssen D, Kurreeman F, et al. Identification of a novel non-coding mutation in C1qB in a Dutch child with C1q deficiency associated with recurrent infections. Immunobiology. 2015;220:422-7 pubmed publisher
    ..We identified the mutation using deep-sequencing. By qPCR we studied the mRNA expression of C1qA, C1qB and C1qC in the PBMCs of the patient...
  40. Hinkelbein J, Jansen S, Iovino I, Kruse S, Meyer M, Cirillo F, et al. Thirty Minutes of Hypobaric Hypoxia Provokes Alterations of Immune Response, Haemostasis, and Metabolism Proteins in Human Serum. Int J Mol Sci. 2017;18: pubmed publisher
    ..1 ± 1.3% to 89.2 ± 1.8% during HH. Expression of 14 spots (i.e., 10 proteins: ALB, PGK1, APOE, GAPDH, C1QA, C1QB, CAT, CA1, F2, and CLU) was significantly altered...
  41. Stoyanova V, Petrova S, Tchorbadjieva M, Deliyska B, Vasilev V, Tsacheva I. New insight into the autoimmunogenicity of the complement protein C1q. Mol Immunol. 2011;48:678-82 pubmed publisher
    ..The presence of anti-gC1q in both healthy and diseased humans also implies that these antibodies, unlike anti-CLR, may have a contribution to an onset of autoimmunity. ..
  42. Lindblom R, Aeinehband S, Ström M, Al Nimer F, Sandholm K, Khademi M, et al. Complement Receptor 2 is increased in cerebrospinal fluid of multiple sclerosis patients and regulates C3 function. Clin Immunol. 2016;166-167:89-95 pubmed publisher
    ..These results propose a novel function for CR2/sCR2 in human neuroinflammatory conditions. ..
  43. Reid K, Gagnon J, Frampton J. Completion of the amino acid sequences of the A and B chains of subcomponent C1q of the first component of human complement. Biochem J. 1982;203:559-69 pubmed
    ..Structure prediction studies indicate that both the A and B chain C-terminal regions may adopt a predominantly beta-type structure with apparently little alpha-helical structure. ..
  44. Petry F. Molecular basis of hereditary C1q deficiency. Immunobiology. 1998;199:286-94 pubmed
  45. Pflieger D, Przybylski C, Gonnet F, Le Caer J, Lunardi T, Arlaud G, et al. Analysis of human C1q by combined bottom-up and top-down mass spectrometry: detailed mapping of post-translational modifications and insights into the C1r/C1s binding sites. Mol Cell Proteomics. 2010;9:593-610 pubmed publisher
    ..They are thus fully available and in an appropriate position to interact with the C1r and C1s protease partners of C1q and are therefore likely to play an essential role in C1 assembly. ..
  46. Martin M, Leffler J, Blom A. Annexin A2 and A5 serve as new ligands for C1q on apoptotic cells. J Biol Chem. 2012;287:33733-44 pubmed
    ..The knowledge, that annexin A2 and A5 act as ligands for C1q on apoptotic cells, sheds new light on the pathophysiology of autoimmune diseases. ..
  47. Kelly K, Liu Y, Zhang J, Dominguez J. Renal C3 complement component: feed forward to diabetic kidney disease. Am J Nephrol. 2015;41:48-56 pubmed publisher
    ..The classic complement pathway was activated in diabetic kidneys with significant increases of C1qa, C1qb, and C1qc mRNAs in DI over LS...
  48. Bhattad S, Rawat A, Gupta A, Suri D, Garg R, de Boer M, et al. Early Complement Component Deficiency in a Single-Centre Cohort of Pediatric Onset Lupus. J Clin Immunol. 2015;35:777-85 pubmed publisher
    ..Mutation analysis of C1qA gene revealed a homozygous nonsense mutation: C1QA (NM_015991) c.622C>T, p.Q208X in one child...
  49. Ho M, Manughian Peter A, Spivia W, Taylor A, Fraser D. Macrophage molecular signaling and inflammatory responses during ingestion of atherogenic lipoproteins are modulated by complement protein C1q. Atherosclerosis. 2016;253:38-46 pubmed publisher
    ..This study identifies potential molecular mechanisms for the beneficial role C1q plays in early atherosclerosis. ..
  50. He D, An Y, Li Y, Wang J, Wu G, Chen L, et al. RNA sequencing reveals target genes of temporomandibular joint osteoarthritis in rats after the treatment of low-intensity pulsed ultrasound. Gene. 2018;672:126-136 pubmed publisher
    ..Some of these genes were proved to be related to OA, such as matrix-degrading enzyme (ADAMTS-8), complement (C1qa, C3, C5aR1). Some were reported for the first time in TMJ-OA, such as circadian gene (Per-2, Dbp, Npas2 and Arntl)...
  51. Namjou B, Gray McGuire C, Sestak A, Gilkeson G, Jacob C, Merrill J, et al. Evaluation of C1q genomic region in minority racial groups of lupus. Genes Immun. 2009;10:517-24 pubmed publisher
    ..In this study, we evaluated 17 single nucleotide polymorphisms (SNPs) across 37 kb of C1QA, C1QB and C1QC in a lupus cohort of individuals of the African-American and Hispanic origin...
  52. Thielens N, Tedesco F, Bohlson S, Gaboriaud C, Tenner A. C1q: A fresh look upon an old molecule. Mol Immunol. 2017;89:73-83 pubmed publisher
    ..This review summarizes the classical functions of C1q and reviews novel discoveries within the field. ..
  53. Norris G, Smirnov I, Filiano A, Shadowen H, Cody K, Thompson J, et al. Neuronal integrity and complement control synaptic material clearance by microglia after CNS injury. J Exp Med. 2018;215:1789-1801 pubmed publisher
    ..RNA sequencing reveals C1q and CD11b/CR3 involvement in clearance of debris by dLGN-resident microglia. Indeed, C1qa-/- and Itgam-/- mice exhibit impaired postinjury debris clearance...
  54. Nauta A, Bottazzi B, Mantovani A, Salvatori G, Kishore U, Schwaeble W, et al. Biochemical and functional characterization of the interaction between pentraxin 3 and C1q. Eur J Immunol. 2003;33:465-73 pubmed
    ..These results indicate that PTX3 can both inhibit and activate the classical complement pathway by binding C1q, depending on the way it is presented. PTX3 may therefore be involved in the regulation of the innate immune response. ..
  55. Soto I, Graham L, Richter H, Simeone S, Radell J, Grabowska W, et al. APOE Stabilization by Exercise Prevents Aging Neurovascular Dysfunction and Complement Induction. PLoS Biol. 2015;13:e1002279 pubmed publisher
    ..and correlated strongly with an increase in neuroinflammation including up-regulation of complement component C1QA in microglia/monocytes...
  56. Watford W, Wright J, Hester C, Jiang H, Frank M. Surfactant protein A regulates complement activation. J Immunol. 2001;167:6593-600 pubmed
    ..We hypothesize that SP-A may serve a protective role in the lung by preventing C1q-mediated complement activation and inflammation along the delicate alveolar epithelium. ..
  57. Krumdieck R, Hook M, Rosenberg L, Volanakis J. The proteoglycan decorin binds C1q and inhibits the activity of the C1 complex. J Immunol. 1992;149:3695-701 pubmed
    ..Furthermore, neither the core protein nor the glycosaminoglycan chain of decorin inhibited C1, indicating that the intact proteoglycan is necessary for functional activity. ..
  58. Wouters D, Brouwer M, Daha M, Hack C. Studies on the haemolytic activity of circulating C1q-C3/C4 complexes. Mol Immunol. 2008;45:1893-9 pubmed
    ..These complexes are still able to interact with C1r and C1s to form a C1 complex, but seem to have a reduced activity as compared to C1q not carrying C3- or C4-fragments. ..
  59. Lewis M, Malik T, Ehrenstein M, Boyle J, Botto M, Haskard D. Immunoglobulin M is required for protection against atherosclerosis in low-density lipoprotein receptor-deficient mice. Circulation. 2009;120:417-26 pubmed publisher
    ..Increased apoptosis was observed in aortic root lesions of both sIgM.Ldlr(-/-) and C1qa.Ldlr(-/-) mice...
  60. Yu A, Song L, Murray K, van der List D, Sun C, Shen Y, et al. Mitochondrial complex I deficiency leads to inflammation and retinal ganglion cell death in the Ndufs4 mouse. Hum Mol Genet. 2015;24:2848-60 pubmed publisher
    ..functional loss at P22, including β-2 microglobulin and Cx3cr1, and during vision loss at P31 (B2m, Tlr 2, 3, 4, C1qa, Cx3cr1 and Fas)...
  61. Goshima M, Sekiguchi R, Matsushita M, Nonaka M. The complement system of elasmobranches revealed by liver transcriptome analysis of a hammerhead shark, Sphyrna zygaena. Dev Comp Immunol. 2016;61:13-24 pubmed publisher
    ..No MBL, ficolin, C1qA or C1qC were found...
  62. Tas S, Klickstein L, Barbashov S, Nicholson Weller A. C1q and C4b bind simultaneously to CR1 and additively support erythrocyte adhesion. J Immunol. 1999;163:5056-63 pubmed
  63. Cresci G, Allende D, McMullen M, Nagy L. Alternative complement pathway component Factor D contributes to efficient clearance of tissue debris following acute CClâ‚„-induced injury. Mol Immunol. 2015;64:9-17 pubmed publisher
    ..In these studies we utilize mice deficient in C1qa, C4 and Factor D, lacking the classical, classical/MBL, and alternative pathways of complement activation, ..
  64. Smathers R, Chiang D, McMullen M, Feldstein A, Roychowdhury S, Nagy L. Soluble IgM links apoptosis to complement activation in early alcoholic liver disease in mice. Mol Immunol. 2016;72:9-18 pubmed publisher
    ..Female C57BL/6 wild-type, C1qa(-/-), BID(-/-) and sIgM(-/-) mice were fed ethanol containing liquid diets or pair-fed control diets...
  65. Hooshmand M, Nguyen H, Piltti K, Benavente F, Hong S, Flanagan L, et al. Neutrophils Induce Astroglial Differentiation and Migration of Human Neural Stem Cells via C1q and C3a Synthesis. J Immunol. 2017;199:1069-1085 pubmed publisher
    ..Collectively, these data suggest that modulation of the innate/humoral inflammatory microenvironment may impact the potential of cell-based therapies for recovery and repair following CNS pathology. ..
  66. Topaloglu R, Bakkaloglu A, Slingsby J, Mihatsch M, Pascual M, Norsworthy P, et al. Molecular basis of hereditary C1q deficiency associated with SLE and IgA nephropathy in a Turkish family. Kidney Int. 1996;50:635-42 pubmed
    ..No further examples of this mutation were found. ..
  67. Watkins L, Neal J, Loveless S, Michailidou I, Ramaglia V, Rees M, et al. Complement is activated in progressive multiple sclerosis cortical grey matter lesions. J Neuroinflammation. 2016;13:161 pubmed publisher
    ..Expression of the transcript for C1qA was noted in neurons and the activation fragment and opsonin C3b-labelled neurons and glia in the MS cortical and ..
  68. Yuan H, Chen R, Tariq M, Liu Y, Sun Y, Xia C. Crystal structure of zebrafish complement 1qA globular domain. Protein Sci. 2016;25:1883-9 pubmed publisher
    ..Here, the first non-mammalian structure, zebrafish C1qA globular domain (Dare-C1qAgD) was solved...
  69. Bing D, Almeda S, Isliker H, Lahav J, Hynes R. Fibronectin binds to the C1q component of complement. Proc Natl Acad Sci U S A. 1982;79:4198-201 pubmed
  70. Howell G, MacNicoll K, Braine C, Soto I, Macalinao D, Sousa G, et al. Combinatorial targeting of early pathways profoundly inhibits neurodegeneration in a mouse model of glaucoma. Neurobiol Dis. 2014;71:44-52 pubmed publisher
    ..We discovered that combined targeting of the endothelin (Bosentan) and complement (C1qa mutation) systems is profoundly protective...
  71. Silverman S, Kim B, Howell G, Miller J, John S, Wordinger R, et al. C1q propagates microglial activation and neurodegeneration in the visual axis following retinal ischemia/reperfusion injury. Mol Neurodegener. 2016;11:24 pubmed publisher
    ..of a retinal ischemia/reperfusion (I/R) injury on glial activation and neurodegeneration in wild type (WT) and C1qa-deficient mice in the retina and superior colliculus (SC)...
  72. Lui H, Zhang J, Makinson S, Cahill M, Kelley K, Huang H, et al. Progranulin Deficiency Promotes Circuit-Specific Synaptic Pruning by Microglia via Complement Activation. Cell. 2016;165:921-35 pubmed publisher
    ..Remarkably, deleting C1qa gene significantly reduces synaptic pruning by Grn(-/-) microglia and mitigates neurodegeneration, behavioral ..
  73. Chew C, Chua K, Lian L, Puah S, Tan S. PCR-RFLP genotyping of C1q mutations and single nucleotide polymorphisms in Malaysian patients with systemic lupus erythematosus. Hum Biol. 2008;80:83-93 pubmed
    Five types of known mutations within the C1q gene [located at C1qA-Gln186 (C >T), C1qB-Gly15 (G >A), C1qB-Arg150 (C >T), C1qC-Gly6 (G >A), and C1qC-Arg41 (C >T)] and two SNPs located at C1qA-Gly70 (G/A) and C1qC-Pro14 (T/C) ..
  74. Li J, Ge X, Wang X, Liu X, Ma J. Complement System in the Pathogenesis of Benign Lymphoepithelial Lesions of the Lacrimal Gland. PLoS ONE. 2016;11:e0148290 pubmed publisher
    ..14 complement system-related genes in the pathologic tissue, including C2, C3, ITGB2, CR2, C1QB, CR1, ITGAX, CFP, C1QA, C4B|C4A, FANCA, C1QC, C3AR1 and CFHR4, were significantly upregulated while 7 other complement system-related ..
  75. Fonseca M, Chu S, Hernandez M, Fang M, Modarresi L, Selvan P, et al. Cell-specific deletion of C1qa identifies microglia as the dominant source of C1q in mouse brain. J Neuroinflammation. 2017;14:48 pubmed publisher
    ..To identify the source(s) of C1q in the brain, the C1qa gene was selectively inactivated in the microglia or Thy-1+ neurons in both wild type mice and a mouse ..
  76. Su H, Boackle R. Interaction of the envelope glycoprotein of human immunodeficiency virus with C1q and fibronectin under conditions present in human saliva. Mol Immunol. 1991;28:811-7 pubmed
    ..e. to the salivary sediment), may play an important role in the reduction of HIV transmission via saliva. Further studies will be needed to test the latter speculation. ..
  77. Sjöberg A, Onnerfjord P, Morgelin M, Heinegard D, Blom A. The extracellular matrix and inflammation: fibromodulin activates the classical pathway of complement by directly binding C1q. J Biol Chem. 2005;280:32301-8 pubmed
    ..Taken together our observations indicate fibromodulin as one factor involved in the sustained inflammation of the joint. ..
  78. Zervou M, Vazgiourakis V, Yilmaz N, Kontaki E, Trouw L, Toes R, et al. TRAF1/C5, eNOS, C1q, but not STAT4 and PTPN22 gene polymorphisms are associated with genetic susceptibility to systemic lupus erythematosus in Turkey. Hum Immunol. 2011;72:1210-3 pubmed publisher
    ..These data highlight the importance of comparative studies in different populations to confirm the previously detected genetic associations. ..
  79. Gueguen C, Bouley J, Moussu H, Luce S, Duchateau M, Chamot Rooke J, et al. Changes in markers associated with dendritic cells driving the differentiation of either TH2 cells or regulatory T cells correlate with clinical benefit during allergen immunotherapy. J Allergy Clin Immunol. 2016;137:545-58 pubmed publisher
    ..AIT course concomitantly with an upregulation of DCreg cell-associated markers, including complement C1q subcomponent subunit A (C1QA), FcγRIIIA, ferritin light chain (FTL), and solute carrier organic anion transporter ..
  80. Verneret M, Tacnet Delorme P, Osman R, Awad R, Grichine A, Kleman J, et al. Relative contribution of c1q and apoptotic cell-surface calreticulin to macrophage phagocytosis. J Innate Immun. 2014;6:426-34 pubmed publisher
    ..e. by integrating the molecular changes that could occur at the surface of dying cells. ..
  81. Son M, Diamond B, Santiago Schwarz F. Fundamental role of C1q in autoimmunity and inflammation. Immunol Res. 2015;63:101-6 pubmed publisher
  82. Vasek M, Garber C, Dorsey D, Durrant D, Bollman B, Soung A, et al. A complement-microglial axis drives synapse loss during virus-induced memory impairment. Nature. 2016;534:538-43 pubmed publisher
    ..b>C1QA was upregulated and localized to microglia, infected neurons and presynaptic terminals during WNV neuroinvasive ..
  83. Prohaszka Z, Nemes J, Hidvegi T, Toth F, Kerekes K, Erdei A, et al. Two parallel routes of the complement-mediated antibody-dependent enhancement of HIV-1 infection. AIDS. 1997;11:949-58 pubmed
  84. Howell G, Macalinao D, Sousa G, Walden M, Soto I, Kneeland S, et al. Molecular clustering identifies complement and endothelin induction as early events in a mouse model of glaucoma. J Clin Invest. 2011;121:1429-44 pubmed publisher
    ..Mice with a mutation in complement component 1a (C1qa) were protected from glaucoma...
  85. Kölm R, Schaller M, Roumenina L, Niemiec I, Kremer Hovinga J, Khanicheh E, et al. Von Willebrand Factor Interacts with Surface-Bound C1q and Induces Platelet Rolling. J Immunol. 2016;197:3669-3679 pubmed
    ..This direct interaction might contribute to the pathogenic mechanisms in complement-mediated, inflammatory diseases. ..
  86. Pednekar L, Pathan A, Paudyal B, Tsolaki A, Kaur A, Abozaid S, et al. Analysis of the Interaction between Globular Head Modules of Human C1q and Its Candidate Receptor gC1qR. Front Immunol. 2016;7:567 pubmed publisher
  87. Hong Q, Sze C, Lin S, Lee M, He R, Schultz L, et al. Complement C1q activates tumor suppressor WWOX to induce apoptosis in prostate cancer cells. PLoS ONE. 2009;4:e5755 pubmed publisher
    ..Downregulation of C1q enhances prostate hyperplasia and cancerous formation due to failure of WOX1 activation. ..
  88. Xavier S, Sahu R, Landes S, Yu J, Taylor R, Ayyadevara S, et al. Pericytes and immune cells contribute to complement activation in tubulointerstitial fibrosis. Am J Physiol Renal Physiol. 2017;312:F516-F532 pubmed publisher
    ..Although deletion of C1qA did not prevent kidney fibrosis, global deletion of C3 reduced macrophage infiltration, reduced synthesis of C3 ..
  89. Jarva H, Jokiranta T, Hellwage J, Zipfel P, Meri S. Regulation of complement activation by C-reactive protein: targeting the complement inhibitory activity of factor H by an interaction with short consensus repeat domains 7 and 8-11. J Immunol. 1999;163:3957-62 pubmed
    ..Thereby, CRP could restrict excessive complement attack in tissues while allowing a temporarily enhanced AP activity against invading microbes in blood. ..
  90. Depboylu C, Schafer M, Arias Carrión O, Oertel W, Weihe E, Höglinger G. Possible involvement of complement factor C1q in the clearance of extracellular neuromelanin from the substantia nigra in Parkinson disease. J Neuropathol Exp Neurol. 2011;70:125-32 pubmed publisher
    ..Thus, we present evidence suggesting that microglia are capable of phagocytosing and clearing cellular debris of degenerating neurons from the SNc through a C1q-mediated pathway in PD. ..
  91. Ho N, Camps M, de Haas E, Trouw L, Verbeek J, Ossendorp F. C1q-Dependent Dendritic Cell Cross-Presentation of In Vivo-Formed Antigen-Antibody Complexes. J Immunol. 2017;198:4235-4243 pubmed publisher
    ..Ag targeting system that uptake by splenic APC subsets is severely hampered in mice lacking complement factor C1q (C1qa-/-)...