Gene Symbol: C1q
Description: complement component 1, q subcomponent, alpha polypeptide
Alias: AI255395, C1q, complement C1q subcomponent subunit A
Species: mouse
Products:     C1q

Top Publications

  1. Chu Y, Jin X, Parada I, Pesic A, Stevens B, Barres B, et al. Enhanced synaptic connectivity and epilepsy in C1q knockout mice. Proc Natl Acad Sci U S A. 2010;107:7975-80 pubmed publisher
    ..A complement cascade protein, C1q, is involved in this process...
  2. Botto M, Dell Agnola C, Bygrave A, Thompson E, Cook H, Petry F, et al. Homozygous C1q deficiency causes glomerulonephritis associated with multiple apoptotic bodies. Nat Genet. 1998;19:56-9 pubmed
    ..In contrast, inherited deficiency of classical pathway components, particularly C1q (ref. 1), is powerfully associated with the development of SLE...
  3. Taylor P, Carugati A, Fadok V, Cook H, Andrews M, Carroll M, et al. A hierarchical role for classical pathway complement proteins in the clearance of apoptotic cells in vivo. J Exp Med. 2000;192:359-66 pubmed
    ..to the position of the missing protein in the activation pathway, with the severest disease associated with C1q deficiency...
  4. Mitchell D, Pickering M, Warren J, Fossati Jimack L, Cortes Hernandez J, Cook H, et al. C1q deficiency and autoimmunity: the effects of genetic background on disease expression. J Immunol. 2002;168:2538-43 pubmed
    Gene-targeted C1q-deficient mice have been shown to develop a syndrome reminiscent of human systemic lupus erythematosus with antinuclear Abs and proliferative glomerulonephritis...
  5. Stephan A, Madison D, Mateos J, Fraser D, Lovelett E, Coutellier L, et al. A dramatic increase of C1q protein in the CNS during normal aging. J Neurosci. 2013;33:13460-74 pubmed publisher
    ..b>C1q, the initiating protein of the classical complement cascade and powerful effector of the peripheral immune response,..
  6. Vandivier R, Ogden C, Fadok V, Hoffmann P, Brown K, Botto M, et al. Role of surfactant proteins A, D, and C1q in the clearance of apoptotic cells in vivo and in vitro: calreticulin and CD91 as a common collectin receptor complex. J Immunol. 2002;169:3978-86 pubmed
    ..Other collectins, such as mannose-binding lectin and the collectin-like C1q, have been shown to bind to apoptotic cells and drive ingestion through interaction with calreticulin and CD91 on ..
  7. Cutler A, Botto M, van Essen D, Rivi R, Davies K, Gray D, et al. T cell-dependent immune response in C1q-deficient mice: defective interferon gamma production by antigen-specific T cells. J Exp Med. 1998;187:1789-97 pubmed
    The role of the classical complement pathway in humoral immune responses was investigated in gene-targeted C1q-deficient mice (C1qA-/-)...
  8. Baruah P, Dumitriu I, Malik T, Cook H, Dyson J, Scott D, et al. C1q enhances IFN-gamma production by antigen-specific T cells via the CD40 costimulatory pathway on dendritic cells. Blood. 2009;113:3485-93 pubmed publisher
    Dendritic cells (DCs) are known to produce C1q, the initiator of the classical complement pathway...
  9. Zhou J, Fonseca M, Pisalyaput K, Tenner A. Complement C3 and C4 expression in C1q sufficient and deficient mouse models of Alzheimer's disease. J Neurochem. 2008;106:2080-92 pubmed publisher
    ..beta-pleated sheet conformation are associated with activated microglia and astrocytes, are colocalized with C1q and other complement activation products, and appear at the time of cognitive decline in AD...

More Information


  1. Kang Y, Do Y, Lee H, Park S, Cheong C, Lynch R, et al. A dominant complement fixation pathway for pneumococcal polysaccharides initiated by SIGN-R1 interacting with C1q. Cell. 2006;125:47-58 pubmed
    ..We found that SIGN-R1 directly bound the complement C1 subcomponent, C1q, and assembled a C3 convertase, but without the traditional requirement for either antibody or factor B...
  2. Walsh M, Bourcier T, Takahashi K, Shi L, Busche M, Rother R, et al. Mannose-binding lectin is a regulator of inflammation that accompanies myocardial ischemia and reperfusion injury. J Immunol. 2005;175:541-6 pubmed
    ..Significantly, mice that lack a major component of the classical complement pathway initiation complex (C1q) but have an intact MBL complement pathway, are not protected from injury...
  3. Hart M, Ceonzo K, Shaffer L, Takahashi K, Rother R, Reenstra W, et al. Gastrointestinal ischemia-reperfusion injury is lectin complement pathway dependent without involving C1q. J Immunol. 2005;174:6373-80 pubmed
    ..The role of the classical and lectin complement pathways in GI/R injury was evaluated using C1q-deficient (C1q KO), MBL-A/C-deficient (MBL-null), complement factor 2- and factor B-deficient (C2/fB KO), and wild-..
  4. Cortes Hernandez J, Fossati Jimack L, Petry F, Loos M, Izui S, Walport M, et al. Restoration of C1q levels by bone marrow transplantation attenuates autoimmune disease associated with C1q deficiency in mice. Eur J Immunol. 2004;34:3713-22 pubmed
    b>C1q deficiency in both humans and mice is strongly associated with autoimmunity. We have previously shown that bone marrow transplantation (BMT) restored C1q levels in C1q-deficient (C1qa(-/-)) mice...
  5. Fonseca M, Zhou J, Botto M, Tenner A. Absence of C1q leads to less neuropathology in transgenic mouse models of Alzheimer's disease. J Neurosci. 2004;24:6457-65 pubmed
    b>C1q, the recognition component of the classical complement activation pathway, is a multifunctional protein known to be expressed in brain of Alzheimer's disease (AD) patients...
  6. Mitchell D, Taylor P, Cook H, Moss J, Bygrave A, Walport M, et al. Cutting edge: C1q protects against the development of glomerulonephritis independently of C3 activation. J Immunol. 1999;162:5676-9 pubmed
    b>C1q-deficient (C1qa-/-) mice develop antinuclear Abs and glomerulonephritis (GN) characterized by multiple apoptotic bodies...
  7. Botto M. C1q knock-out mice for the study of complement deficiency in autoimmune disease. Exp Clin Immunogenet. 1998;15:231-4 pubmed
    In humans, homozygous deficiency of the first component of the classical pathway of complement, C1q, is a powerful disease susceptibility factor for the development of systemic lupus erythematosus (SLE)...
  8. Rupprecht T, Angele B, Klein M, Heesemann J, Pfister H, Botto M, et al. Complement C1q and C3 are critical for the innate immune response to Streptococcus pneumoniae in the central nervous system. J Immunol. 2007;178:1861-9 pubmed
    ..Thereby, we used mice deficient in C1q, lacking only the classical pathway, and C3, lacking all three complement activation pathways...
  9. Bhatia V, Yun S, Leung V, Grimsditch D, Benson G, Botto M, et al. Complement C1q reduces early atherosclerosis in low-density lipoprotein receptor-deficient mice. Am J Pathol. 2007;170:416-26 pubmed
    We explored the role of the classic complement pathway in atherogenesis by intercrossing C1q-deficient mice (C1qa-/-) with low-density lipoprotein receptor knockout mice (Ldlr-/-). Mice were fed a normal rodent diet until 22 weeks of age...
  10. Baruah P, Simpson E, Dumitriu I, Derbyshire K, Coe D, Addey C, et al. Mice lacking C1q or C3 show accelerated rejection of minor H disparate skin grafts and resistance to induction of tolerance. Eur J Immunol. 2010;40:1758-67 pubmed publisher
    ..Here, we report that female mice deficient in C1q (C1qa(-/-)) or C3 (C3(-/-)) reject male syngeneic grafts (HY incompatible) at an accelerated rate compared with WT ..
  11. Tong H, Li Y, Stahl G, Thurman J. Enhanced susceptibility to acute pneumococcal otitis media in mice deficient in complement C1qa, factor B, and factor B/C2. Infect Immun. 2010;78:976-83 pubmed publisher
    ..pneumoniae from the middle ear and dissemination to the bloodstream during AOM. ..
  12. Galvan M, Luchetti S, Burgos A, Nguyen H, Hooshmand M, Hamers F, et al. Deficiency in complement C1q improves histological and functional locomotor outcome after spinal cord injury. J Neurosci. 2008;28:13876-88 pubmed publisher
    ..Thus, to investigate the role of the classical complement pathway in contusion-induced SCI, male C1q knock-out (KO) and wild-type (WT) mice on a complement sufficient background (BUB) received a mild-moderate T9 ..
  13. Nash J, Taylor P, Botto M, Norsworthy P, Davies K, Walport M. Immune complex processing in C1q-deficient mice. Clin Exp Immunol. 2001;123:196-202 pubmed
    ..We explored the processing of IC in mice deficient in complement component C1q. 125I-labelled IC comprising Hepatitis B surface antigen (HBsAg)/human anti-HBsAg (HBsAg/Ab) were injected ..
  14. Naito A, Sumida T, Nomura S, Liu M, Higo T, Nakagawa A, et al. Complement C1q activates canonical Wnt signaling and promotes aging-related phenotypes. Cell. 2012;149:1298-313 pubmed publisher
    ..We here report that complement C1q activates canonical Wnt signaling and promotes aging-associated decline in tissue regeneration...
  15. Ji H, Ohmura K, Mahmood U, Lee D, Hofhuis F, Boackle S, et al. Arthritis critically dependent on innate immune system players. Immunity. 2002;16:157-68 pubmed
    ..We suggest that autoimmune disease, even one that is organ specific, can occur when mobilization of an adaptive immune response results in runaway activation of the innate response. ..
  16. Manderson A, Pickering M, Botto M, Walport M, Parish C. Continual low-level activation of the classical complement pathway. J Exp Med. 2001;194:747-56 pubmed
    ..By the use of complement- and Ig-deficient mice it was found that C1q, C4, C2, and plasma Ig were all required for this spontaneous C3 activation, with the alternative complement ..
  17. Li Q, Li Y, Stahl G, Thurman J, He Y, Tong H. Essential role of factor B of the alternative complement pathway in complement activation and opsonophagocytosis during acute pneumococcal otitis media in mice. Infect Immun. 2011;79:2578-85 pubmed publisher
  18. Yuste J, Botto M, Paton J, Holden D, Brown J. Additive inhibition of complement deposition by pneumolysin and PspA facilitates Streptococcus pneumoniae septicemia. J Immunol. 2005;175:1813-9 pubmed
    ..pneumoniae to successfully cause septicemia. Targeting mechanisms of complement inhibition could be an effective therapeutic strategy for patients with septicemia due to S. pneumoniae or other bacterial pathogens. ..
  19. Cutler A, Cornall R, Ferry H, Manderson A, Botto M, Walport M. Intact B cell tolerance in the absence of the first component of the classical complement pathway. Eur J Immunol. 2001;31:2087-93 pubmed
    ..To elucidate the role of the classical pathway of complement in the maintenance of B cell tolerance, C1q-deficient (C1qa-/-) mice were bred with anti-hen egg lysozyme (HEL) immunoglobulin (Ig(HEL)) and soluble HEL (sHEL) ..
  20. Ferry H, Potter P, Crockford T, Nijnik A, Ehrenstein M, Walport M, et al. Increased positive selection of B1 cells and reduced B cell tolerance to intracellular antigens in c1q-deficient mice. J Immunol. 2007;178:2916-22 pubmed
    ..In this study, we show that C1q deficiency increases the positive selection of B1b B cells and IgM autoantibodies by an intracellular self Ag, ..
  21. Quartier P, Potter P, Ehrenstein M, Walport M, Botto M. Predominant role of IgM-dependent activation of the classical pathway in the clearance of dying cells by murine bone marrow-derived macrophages in vitro. Eur J Immunol. 2005;35:252-60 pubmed
    ..The addition of C1q rectified the phagocytic defect seen in the presence of C1q-deficient serum in vitro but had no effect on the ..
  22. Stevens B, Allen N, Vazquez L, Howell G, Christopherson K, Nouri N, et al. The classical complement cascade mediates CNS synapse elimination. Cell. 2007;131:1164-78 pubmed
    ..Here we show that C1q, the initiating protein in the classical complement cascade, is expressed by postnatal neurons in response to ..
  23. 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
    ..Targeting early molecular events, such as complement and endothelin induction, may provide effective new treatments for human glaucoma. ..
  24. Williams P, Tribble J, Pepper K, Cross S, Morgan B, Morgan J, et al. Inhibition of the classical pathway of the complement cascade prevents early dendritic and synaptic degeneration in glaucoma. Mol Neurodegener. 2016;11:26 pubmed publisher
    ..This study further supports assessing the potential for complement-modulating therapeutics for the prevention of retinal ganglion cell degeneration in glaucoma. ..
  25. Erlich P, Dumestre Pérard C, Ling W, Lemaire Vieille C, Schoehn G, Arlaud G, et al. Complement protein C1q forms a complex with cytotoxic prion protein oligomers. J Biol Chem. 2010;285:19267-76 pubmed publisher
    A growing number of studies have investigated the interaction between C1q and PrP, but the oligomeric form of PrP involved in this interaction remains to be determined...
  26. Møller Kristensen M, Hamblin M, Thiel S, Jensenius J, Takahashi K. Burn injury reveals altered phenotype in mannan-binding lectin-deficient mice. J Invest Dermatol. 2007;127:1524-31 pubmed
    ..Mice lacking C1q, C4, or C3 did not show the lack of eschar separation seen in MBL null-burn phenotype...
  27. Mehlhop E, Diamond M. Protective immune responses against West Nile virus are primed by distinct complement activation pathways. J Exp Med. 2006;203:1371-81 pubmed
    ..Genetic deficiencies in C1q, C4, factor B, or factor D all resulted in increased mortality in mice, suggesting that all activation pathways ..
  28. Mihai S, Chiriac M, Takahashi K, Thurman J, Holers V, Zillikens D, et al. The alternative pathway of complement activation is critical for blister induction in experimental epidermolysis bullosa acquisita. J Immunol. 2007;178:6514-21 pubmed
    ..To further dissect the role of the different complement activation pathways in this model, we injected C1q-deficient, mannan-binding lectin-deficient, and factor B-deficient mice with rabbit Abs against murine type VII ..
  29. Greenlee Wacker M, Briseño C, Galvan M, Moriel G, Velazquez P, Bohlson S. Membrane-associated CD93 regulates leukocyte migration and C1q-hemolytic activity during murine peritonitis. J Immunol. 2011;187:3353-61 pubmed publisher
    ..b>C1q-hemolytic activity in CD93(-/-) mice was decreased by 22% at time zero and by 46% 3 h after thioglycollate ..
  30. Xiao J, Li Y, Gressitt K, He H, Kannan G, Schultz T, et al. Cerebral complement C1q activation in chronic Toxoplasma infection. Brain Behav Immun. 2016;58:52-56 pubmed publisher
    ..Complement factor C1q is part of a classic immune pathway that functions peripherally to tag and remove infectious agents and cellular ..
  31. Verschoor A, Neuenhahn M, Navarini A, Graef P, Plaumann A, Seidlmeier A, et al. A platelet-mediated system for shuttling blood-borne bacteria to CD8?+ dendritic cells depends on glycoprotein GPIb and complement C3. Nat Immunol. 2011;12:1194-201 pubmed publisher
    ..Other gram-positive bacteria also were rapidly tagged by platelets, revealing a broadly active shuttling mechanism for systemic bacteria. ..
  32. Depboylu C, Schorlemmer K, Klietz M, Oertel W, Weihe E, Höglinger G, et al. Upregulation of microglial C1q expression has no effects on nigrostriatal dopaminergic injury in the MPTP mouse model of Parkinson disease. J Neuroimmunol. 2011;236:39-46 pubmed publisher
    Here we analyzed C1q, the initial recognition subcomponent of classical complement activation cascade, in an experimental model of Parkinson disease (PD)...
  33. Tong H, Lambert G, Li Y, Thurman J, Stahl G, Douthitt K, et al. Deletion of the complement C5a receptor alleviates the severity of acute pneumococcal otitis media following influenza A virus infection in mice. PLoS ONE. 2014;9:e95160 pubmed publisher
    ..It is possible that targeting the C5a-C5aR axis might prove useful in attenuating acute pneumococcal OM in patients with influenza infection. ..
  34. Cohen J, Roychowdhury S, McMullen M, Stavitsky A, Nagy L. Complement and alcoholic liver disease: role of C1q in the pathogenesis of ethanol-induced liver injury in mice. Gastroenterology. 2010;139:664-74, 674.e1 pubmed publisher
    ..b>C1q, the recognition subunit of the first complement component, binds to apoptotic cells, thereby activating the ..
  35. Woodman M, Cooley A, Avdiushko R, Bowman A, Botto M, Wooten R, et al. Roles for phagocytic cells and complement in controlling relapsing fever infection. J Leukoc Biol. 2009;86:727-36 pubmed publisher
    ..Together, these findings indicate mphi and/or DC play a critical role in the production of B. hermsii-specific IgM and for antibody-independent control of spirochete levels. ..
  36. Edelson B, Stricker T, Li Z, Dickeson S, Shepherd V, Santoro S, et al. Novel collectin/C1q receptor mediates mast cell activation and innate immunity. Blood. 2006;107:143-50 pubmed
    ..We now report that the alpha2beta1 integrin is a novel receptor for multiple collectins and the C1q complement protein...
  37. 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
    ..we show that PDGFR?-positive pericytes isolated from mice subjected to obstructive or folic acid injury secrete C1q. This was associated with increased production of proinflammatory cytokines, extracellular matrix components, ..
  38. Otten M, Groeneveld T, Flierman R, Rastaldi M, Trouw L, Faber Krol M, et al. Both complement and IgG fc receptors are required for development of attenuated antiglomerular basement membrane nephritis in mice. J Immunol. 2009;183:3980-8 pubmed publisher
    ..Because C1q(-/-) and C4(-/-) mice lacking a functional classical and lectin pathway did develop albuminuria, we suggest ..
  39. Ten V, Yao J, Ratner V, Sosunov S, Fraser D, Botto M, et al. Complement component c1q mediates mitochondria-driven oxidative stress in neonatal hypoxic-ischemic brain injury. J Neurosci. 2010;30:2077-87 pubmed publisher
    ..We report a novel pathway mediating oxidative brain injury after hypoxia-ischemia in which C1q plays a central role...
  40. 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
    The complement component C1q is known to play a controversial role in the pathogenesis of systemic lupus erythematosus, but the underlying mechanisms remain poorly understood...
  41. van Montfoort N, de Jong J, Schuurhuis D, van der Voort E, Camps M, Huizinga T, et al. A novel role of complement factor C1q in augmenting the presentation of antigen captured in immune complexes to CD8+ T lymphocytes. J Immunol. 2007;178:7581-6 pubmed
    ..Importantly, CD8+ T cell proliferation was significantly reduced in mice deficient for C1q. This proliferation could be restored when IC were incubated with purified human C1q before injection...
  42. Giacomassi C, Buang N, Ling G, Crawford G, Cook H, Scott D, et al. Complement C3 Exacerbates Imiquimod-Induced Skin Inflammation and Psoriasiform Dermatitis. J Invest Dermatol. 2017;137:760-763 pubmed publisher
  43. Mascarell L, Airouche S, Berjont N, Gary C, Gueguen C, Fourcade G, et al. The regulatory dendritic cell marker C1q is a potent inhibitor of allergic inflammation. Mucosal Immunol. 2017;10:695-704 pubmed publisher
    The complement subunit C1q was recently identified as a marker for monocyte-derived regulatory dendritic cells supporting the differentiation of interleukin (IL)-10-secreting CD4+ T cells with a suppressive activity...
  44. Stuart L, Takahashi K, Shi L, Savill J, Ezekowitz R. Mannose-binding lectin-deficient mice display defective apoptotic cell clearance but no autoimmune phenotype. J Immunol. 2005;174:3220-6 pubmed
    ..a member of the collectin family with structural similarities to the lung collectins and functional similarities to C1q. Both MBL and C1q activate complement; C1q activates the classical pathway and MBL the lectin pathway...
  45. Garlanda C, Hirsch E, Bozza S, Salustri A, De Acetis M, Nota R, et al. Non-redundant role of the long pentraxin PTX3 in anti-fungal innate immune response. Nature. 2002;420:182-6 pubmed
    ..Thus, the long pentraxin Ptx3 is a secreted pattern-recognition receptor that has a non-redundant role in resistance to selected microbial agents, in particular to the opportunistic fungal pathogen Aspergillus fumigatus. ..
  46. Banda N, Takahashi M, Levitt B, Glogowska M, Nicholas J, Takahashi K, et al. Essential role of complement mannose-binding lectin-associated serine proteases-1/3 in the murine collagen antibody-induced model of inflammatory arthritis. J Immunol. 2010;185:5598-606 pubmed publisher
  47. Link A, Zabel F, Schnetzler Y, Titz A, Brombacher F, Bachmann M. Innate immunity mediates follicular transport of particulate but not soluble protein antigen. J Immunol. 2012;188:3724-33 pubmed publisher
    ..These findings identify size and repetitive structure as critical factors for efficient Ag presentation to B cells and highlight important differences between soluble proteins and viral particles. ..
  48. Lattin J, Greenwood K, Daly N, Kelly G, Zidar D, Clark R, et al. Beta-arrestin 2 is required for complement C1q expression in macrophages and constrains factor-independent survival. Mol Immunol. 2009;47:340-7 pubmed publisher
    ..Here we show that ARRB2 mRNA and protein expression is enriched in macrophages, and that it regulates complement C1q expression and cell survival...
  49. 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
    ..Mice deficient in serum IgM (sIgM) or complement C1q were crossed with Ldlr(-/-) mice and studied on both low-fat and high-fat semisynthetic diets...
  50. Stokol T, O Donnell P, Xiao L, Knight S, Stavrakis G, Botto M, et al. C1q governs deposition of circulating immune complexes and leukocyte Fcgamma receptors mediate subsequent neutrophil recruitment. J Exp Med. 2004;200:835-46 pubmed
    ..This deposition is dependent on complement C1q. IC deposition is associated with leukocyte recruitment...
  51. Idonije O, Akinlade K, Ihenyen O, Arinola O. Complement factors in newly diagnosed Nigerian schizoprenic patients and those on antipsychotic therapy. Niger J Physiol Sci. 2012;27:19-21 pubmed
    ..To address this issue, levels of Complement regulators (C1 inhibitor and C3 activator) and complement factors (C1q, C3c, C4 and C5) were determined in the serum of newly diagnosed drug free schizophrenic patients, schizophrenic ..
  52. Yuste J, Ali S, Sriskandan S, Hyams C, Botto M, Brown J. Roles of the alternative complement pathway and C1q during innate immunity to Streptococcus pyogenes. J Immunol. 2006;176:6112-20 pubmed
    ..Using mice and human serum deficient in either C1q, the first component of the classical pathway, or factor B, an important component of the alternative pathway, we ..
  53. 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
    ..b>C1q, required for several of these complement-mediated activities, is present in the neuropil, microglia, and a subset ..
  54. Mocco J, Mack W, Ducruet A, Sosunov S, Sughrue M, Hassid B, et al. Complement component C3 mediates inflammatory injury following focal cerebral ischemia. Circ Res. 2006;99:209-17 pubmed
    ..To address this issue, we subjected mice deficient in selected complement proteins (C1q, C3, C5) to transient focal cerebral ischemia...
  55. Wood W, Turmaine M, Weber R, Camp V, Maki R, McKercher S, et al. Mesenchymal cells engulf and clear apoptotic footplate cells in macrophageless PU.1 null mouse embryos. Development. 2000;127:5245-52 pubmed
  56. Bialas A, Stevens B. TGF-? signaling regulates neuronal C1q expression and developmental synaptic refinement. Nat Neurosci. 2013;16:1773-82 pubmed publisher
    Immune molecules, including complement proteins C1q and C3, have emerged as critical mediators of synaptic refinement and plasticity...
  57. Kim C, Smith K, Castillejos A, Diaz Aguilar D, Saint Geniez M, Connor K. The alternative complement pathway aids in vascular regression during the early stages of a murine model of proliferative retinopathy. FASEB J. 2016;30:1300-5 pubmed publisher
  58. Singh J, Ahmed A, Girardi G. Role of complement component C1q in the onset of preeclampsia in mice. Hypertension. 2011;58:716-24 pubmed publisher
    ..Complement component C1q has an important role in trophoblast migration, spiral arteries remodeling, and normal placentation...
  59. CARLSON E, Magid R, Petryk A, Georgieff M. Iron deficiency alters expression of genes implicated in Alzheimer disease pathogenesis. Brain Res. 2008;1237:75-83 pubmed publisher
    ..Our results suggest a role for neonatal iron deficiency in dysregulation of genes that may set the stage for long-term neurodegenerative disease and that this may occur through a histone modification mechanism. ..
  60. Turnberg D, Lewis M, Moss J, Xu Y, Botto M, Cook H. Complement activation contributes to both glomerular and tubulointerstitial damage in adriamycin nephropathy in mice. J Immunol. 2006;177:4094-102 pubmed
    ..We used mice deficient in C1q, factor D, C3, and CD59, and compared them with strain-matched controls...
  61. Fossati Jimack L, Cortes Hernandez J, Norsworthy P, Walport M, Cook H, Botto M. C1q deficiency promotes the production of transgenic-derived IgM and IgG3 autoantibodies in anti-DNA knock-in transgenic mice. Mol Immunol. 2008;45:787-95 pubmed
    b>C1q-deficient mice have been shown to develop a lupus-like disease and to display an impaired clearance of apoptotic cells that are enriched in lupus autoantigens...
  62. 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
  63. Shah D, Romero F, Zhu Y, Duong M, Sun J, Walsh K, et al. C1q Deficiency Promotes Pulmonary Vascular Inflammation and Enhances the Susceptibility of the Lung Endothelium to Injury. J Biol Chem. 2015;290:29642-51 pubmed publisher
    ..To test this hypothesis, we investigated the anti-inflammatory actions of C1q in lung endothelial homeostasis and the pulmonary vascular response to LPS or HCl injury...
  64. Radanova M, Vasilev V, Dimitrov T, Deliyska B, Ikonomov V, Ivanova D. Association of rs172378 C1q gene cluster polymorphism with lupus nephritis in Bulgarian patients. Lupus. 2015;24:280-9 pubmed publisher
    ..One of its most severe manifestations is lupus nephritis. Hereditary C1q deficiency is strongly related to SLE but there are very few and inconsistent studies exploring the single ..
  65. Wang Y, Jenkins S, Gu C, Shree A, Martinez Moczygemba M, Herold J, et al. Bacillus anthracis Spore Surface Protein BclA Mediates Complement Factor H Binding to Spores and Promotes Spore Persistence. PLoS Pathog. 2016;12:e1005678 pubmed publisher
    ..anthracis mediated by BclA and CFH that promotes spore persistence in vivo. The findings also suggested an important role of complement in persistent infections and thus have broad implications. ..
  66. Robson M, Cook H, Pusey C, Walport M, Davies K. Antibody-mediated glomerulonephritis in mice: the role of endotoxin, complement and genetic background. Clin Exp Immunol. 2003;133:326-33 pubmed
    ..In this study we show a synergy between antibody and endotoxin in causing a neutrophil influx. We also show that C1q-deficient mice have an increased susceptibility to glomerular inflammation but this is seen only on a mixed 129/Sv ..
  67. Ma Y, Ramachandran A, Ford N, Parada I, Prince D. Remodeling of dendrites and spines in the C1q knockout model of genetic epilepsy. Epilepsia. 2013;54:1232-9 pubmed publisher
    To determine whether developmental synaptic pruning defects in epileptic C1q-knockout (KO) mice are accompanied by postsynaptic abnormalities in dendrites and/or spines...
  68. Elvington A, Atkinson C, Zhu H, Yu J, Takahashi K, Stahl G, et al. The alternative complement pathway propagates inflammation and injury in murine ischemic stroke. J Immunol. 2012;189:4640-7 pubmed publisher
    ..Mice deficient in both the classical and lectin pathways (C1q/MBL deficient) were also protected from cerebral ischemia-reperfusion injury, and there was no detectable C3d ..
  69. Cohen D, Buurma A, Goemaere N, Girardi G, le Cessie S, Scherjon S, et al. Classical complement activation as a footprint for murine and human antiphospholipid antibody-induced fetal loss. J Pathol. 2011;225:502-11 pubmed publisher
    ..Pregnant C57BL/6 mice and mice deficient in C1q and factor D were injected with antiphospholipid antibodies or normal human IgG...
  70. Ali Y, Kenawy H, Muhammad A, Sim R, Andrew P, Schwaeble W. Human L-ficolin, a recognition molecule of the lectin activation pathway of complement, activates complement by binding to pneumolysin, the major toxin of Streptococcus pneumoniae. PLoS ONE. 2013;8:e82583 pubmed publisher
    ..Absence of CP activity in C1q(-/-) mouse serum completely abolished any C3 deposition...
  71. Dahlke K, Wrann C, Sommerfeld O, Sossdorf M, Recknagel P, Sachse S, et al. Distinct different contributions of the alternative and classical complement activation pathway for the innate host response during sepsis. J Immunol. 2011;186:3066-75 pubmed publisher
    ..cecal ligation and puncture (CLP)-induced sepsis in mice lacking either the alternative (fD(-/-)) or classical (C1q(-/-)) complement activation pathway...
  72. Zhang M, Takahashi K, Alicot E, Vorup Jensen T, Kessler B, Thiel S, et al. Activation of the lectin pathway by natural IgM in a model of ischemia/reperfusion injury. J Immunol. 2006;177:4727-34 pubmed
    ..The results reveal that IgM binds initially to ischemic Ag providing a binding site for mannan-binding lectin which subsequently leads to activation of complement and injury. ..
  73. 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
    ..These results represent an important conceptual advance that complement activation and microglia-mediated synaptic pruning are major drivers, rather than consequences, of neurodegeneration caused by progranulin deficiency. ..
  74. Kuehn M, Kim C, Jiang B, Dumitrescu A, Kwon Y. Disruption of the complement cascade delays retinal ganglion cell death following retinal ischemia-reperfusion. Exp Eye Res. 2008;87:89-95 pubmed publisher
    ..It appears that injured RGC are targeted and actively destroyed through complement mediated processes. These results may have implications for the pathophysiology and clinical management of ischemic retinal conditions. ..
  75. Linnartz B, Kopatz J, Tenner A, Neumann H. Sialic acid on the neuronal glycocalyx prevents complement C1 binding and complement receptor-3-mediated removal by microglia. J Neurosci. 2012;32:946-52 pubmed publisher
    ..Several early components of the classical complement cascade including C1q, C1r, C1s, and C3 were produced by cultured mouse microglia...
  76. Moulton E, Atkinson J, Buller R. Surviving mousepox infection requires the complement system. PLoS Pathog. 2008;4:e1000249 pubmed publisher
    ..In summary, the complement system acts in the first few minutes, hours, and days to control this poxviral infection until the adaptive immune response can react, and loss of this system results in lethal infection...
  77. Mangold C, Wronowski B, Du M, Masser D, Hadad N, Bixler G, et al. Sexually divergent induction of microglial-associated neuroinflammation with hippocampal aging. J Neuroinflammation. 2017;14:141 pubmed publisher
    ..Sexually divergent C1q protein expression was confirmed by immunoblotting and immunohistochemistry...