| 1980 |
Native C3 contains a thioester bond (active carbonyl group) that, upon enzymatic cleavage to C3b, enables covalent ester-bond attachment to hydroxyl groups on target surfaces; methylamine modification of native C3 mimics C3b function by reacting with the thioester, exposing a sulfhydryl group in the C3d region and allowing factor B binding and alternative-pathway C3 convertase formation without proteolysis. |
Radiolabeled methylamine/iodoacetamide incorporation, hemolytic activity assays, convertase formation assay with purified factors B and D, anti-C3a antibody inhibition, zymosan particle binding experiments |
The Journal of experimental medicine |
High |
6903192
|
| 1975 |
Properdin (P) binds directly to C3b on cell surfaces and stabilizes the alternative-pathway C3 convertase (C3bBb) by prolonging its half-life up to 10-fold in a dose-dependent manner, without increasing the number of convertase sites; P can transfer between convertase sites carrying its stabilizing activity. |
Hemolytic assay with EAC43B intermediates, dose-response decay kinetics, temperature-dependence binding studies, cell-to-cell transfer experiments |
The Journal of experimental medicine |
High |
1185108
|
| 1979 |
C3b inactivator (C3bINA) together with cofactor beta1H cleaves the alpha-chain of cell-bound C3b into two fragments (C3b-alpha-60 and C3b-alpha-40, held together with the beta-chain by disulfide bonds), generating C3b' (iC3b); this conversion abolishes immune adherence to erythrocytes and the ability to form the amplification C3 convertase, while leaving C3c and C3d antigenic sites intact; trypsin further releases C3b' fragments leaving a 32 kDa C3d-bearing fragment covalently linked to the membrane. |
SDS-PAGE analysis of cell-bound C3b fragments, immune adherence assay, convertase formation assay, trypsin cleavage, anti-C3c/anti-C3d agglutination |
Journal of immunology |
High |
448074
|
| 1979 |
C4 binding protein (C4BP) inhibits assembly and accelerates decay of the classical-pathway C3 convertase (C4b2a) by displacing C2a from C4b binding sites; C4BP also enhances C3b inactivator-mediated cleavage of cell-bound C4b alpha'-chain; removal of C4BP from serum promotes vigorous C3 consumption after C1 addition. |
Hemolytic assay with cellular intermediates (EAC14), immune absorption depletion of C4BP, reconstitution with purified C4BP, Tmax analysis |
Proceedings of the National Academy of Sciences of the United States of America |
High |
293746
|
| 2006 |
Crystal structure of C3b at 4 Å resolution reveals that proteolytic activation of C3 to C3b causes massive domain rearrangements across its 12 domains; the thioester is fully exposed and displaced >85 Å from its buried location in native C3, and a new molecular surface is presented that exposes cryptic binding sites for factor B and complement regulators. |
X-ray crystallography at 4 Å resolution |
Nature |
High |
17051160
|
| 1983 |
Mast cell tryptase cleaves only the alpha-chain of C3, generating C3a anaphylatoxin (identified by SDS-PAGE co-migration, radioimmunoassay, and guinea pig ileum bioassay); heparin co-released from mast cell granules enhances catabolism of the generated C3a by tryptase, thereby down-regulating C3a activity. |
In vitro enzymatic cleavage of purified C3 by tryptase, SDS-PAGE, radioimmunoassay for C3a, guinea pig ileum bioassay, heparin co-incubation experiment |
Journal of immunology |
High |
6339618
|
| 1975 |
Purified human and porcine C3a anaphylatoxins require an intact C-terminal arginine residue for smooth muscle contraction and histamine release from mast cells; removal of the C-terminal arginine abolishes these activities. Both are generated by classical-pathway C4,2 enzyme and alternative-pathway enzymes with equal structure. |
Purification from inulin-activated serum, carboxypeptidase treatment, smooth muscle contraction bioassay, histamine release from mast cells, amino acid sequencing, SDS-PAGE |
The Journal of biological chemistry |
High |
803505
|
| 1983 |
The alternative-pathway C3 convertase (C3b,Bb) is an active, stable complex with a sedimentation coefficient of 10.7 S containing one mole of metal ion (Ni2+ or Mg2+) per mole of complex; the metal ion is located in the Bb subunit and is required for enzyme activity; Ni2+ binds more tightly than Mg2+ to the same site, explaining the enhanced stability of the Ni2+-containing convertase. |
Sucrose density gradient ultracentrifugation, enzymatic activity assay, 63Ni2+ radiolabeling, EDTA chelation, metal displacement experiments |
The Journal of biological chemistry |
High |
6553050
|
| 1981 |
C3b receptors on PMN are non-randomly distributed in small clusters and undergo adsorptive endocytosis via a multivalency-dependent mechanism (bivalent but not monovalent anti-receptor antibody, or cross-linked C3b-opsonized targets trigger internalization); internalized receptor-ligand complexes become inaccessible to surface probes within 10 minutes at 37°C. |
Indirect immunofluorescence with mono/bivalent anti-C3b receptor antibodies, 125I/131I dual radiolabeling endocytosis assay, pronase surface accessibility assay, cross-linking with F(ab')2 anti-C3 |
The Journal of experimental medicine |
High |
7252422
|
| 1982 |
C3b and C3b' (iC3b) receptors on human monocytes mediate attachment but not ingestion of opsonized erythrocytes in resting cells; phorbol esters (PMA) activate phagocytosis specifically through these C3 receptors in a cycloheximide-insensitive, colchicine-sensitive manner that develops after 3 days of culture; the two receptor types function independently. |
Percoll gradient monocyte isolation, erythrocyte rosette/phagocytosis assay with C3b- and C3b'-coated particles, PMA treatment, competitive plating on C3b/C3b'-coated surfaces |
The Journal of experimental medicine |
High |
7153708
|
| 1983 |
Substrate-bound (but not soluble) fibronectin and serum amyloid P component activate C3b and C3bi receptor-mediated phagocytosis in cultured human monocytes via a trans-membrane signal; activation of receptors on the basal surface propagates to apical surface C3 receptors at remote sites. |
Phagocytosis assay with C3b/C3bi-coated erythrocytes, soluble vs. substrate-bound fibronectin comparison, apical/basal surface receptor activity measurement |
The Journal of experimental medicine |
Medium |
6225825
|
| 1983 |
C3a (but not C3a desArg) activates human platelets to aggregate and release serotonin; C3a desArg retains platelet-stimulating activity equal to intact C3a despite loss of anaphylatoxin (smooth muscle) activity, suggesting the platelet-stimulating site and anaphylatoxin site are distinct; ultrastructural evidence shows C3a binding to platelet membranes. |
Platelet aggregation assay with gel-filtered platelets, serotonin release assay, ADP synergism assay, electron microscopy with anti-C3a immunostaining |
The Journal of experimental medicine |
Medium |
6604123
|
| 1997 |
C3a and C5a are chemotactic for human mast cells (HMC-1, cord blood-derived, cutaneous) in a dose-dependent, pertussis-toxin-sensitive manner requiring an extracellular matrix (laminin); C3a and C5a also mobilize intracellular calcium in HMC-1 cells, indicating Gi protein-coupled receptor signaling. |
Modified Boyden chamber chemotaxis assay, laminin dependence experiment, pertussis toxin inhibition, intracellular Ca2+ imaging |
Blood |
Medium |
9108406
|
| 1994 |
C3a and C5a release histamine from human skin mast cells; the C-terminal arginine of both peptides is required for this activity; release is non-cytotoxic, independent of extracellular calcium, and complete within 15 seconds; C3a and C5a act through a site distinct from substance P. |
Histamine release assay from dispersed skin mast cells, carboxypeptidase treatment, metabolic inhibitor controls, substance P antagonist comparison, time-course studies |
The Journal of investigative dermatology |
Medium |
7513741
|
| 2003 |
C3a and C5a are required for liver regeneration after partial hepatectomy; lack of C3 and C5a receptor signaling attenuates NF-κB/STAT-3 activation and IL-6/TNFα induction post-hepatectomy; reconstitution of C3- and C5-deficient mice with exogenous C3a and C5a rescues the regeneration defect. |
Partial hepatectomy in C3-/- and C5-/- mice, genetic reconstitution with recombinant C3a/C5a, NF-κB/STAT-3 activation assay, cytokine measurement |
The Journal of experimental medicine |
High |
12975457
|
| 2004 |
C3a promotes hepatocyte proliferation via the C3a receptor (C3aR) during liver regeneration after CCl4 injury; two waves of complement activation occur; early C3a generation primes hepatocytes for S-phase entry; C3aR-deficient mice show impaired hepatocyte proliferation; C3a reconstitution of C3-/- mice restores proliferative capacity. |
CCl4 liver injury model, C3-/- and C3aR-/- mice, cobra venom factor decomplementation, BrdU incorporation (S-phase entry), serum C3a RIA, C3a reconstitution |
Journal of immunology |
High |
15240660
|
| 2000 |
Genetic deletion of C3a receptor (C3aR) in mice protects against allergen-induced changes in lung physiology in a murine asthma model; human asthmatics generate significant C3a following intra-pulmonary allergen (but not saline) deposition, establishing C3aR-mediated signaling as an effector pathway in asthma. |
C3aR knockout mice, allergen challenge model, lung physiology measurements, C3a ELISA in human BAL fluid |
Nature |
High |
10984054
|
| 2002 |
C3a and C5a from drusen induce VEGF expression in retinal pigment epithelium in vitro and in vivo; genetic ablation of C3aR or C5aR reduces VEGF expression, leukocyte recruitment, and choroidal neovascularization after laser injury; antibody-mediated neutralization or pharmacological receptor blockade also reduces CNV. |
In vitro VEGF induction assay, laser-induced CNV mouse model, C3aR/C5aR knockout mice, antibody neutralization, receptor antagonist pharmacology |
Proceedings of the National Academy of Sciences of the United States of America |
High |
16452172
|
| 2011 |
Complement fragment C3a mediates mutual cell-cell attraction (coattraction) of migrating neural crest cells via C3aR; C3a/C3aR-dependent coattraction maintains cohesive clusters during collective migration by counterbalancing contact inhibition of locomotion; loss of C3aR disrupts collective and coordinated neural crest cell movements. |
Xenopus neural crest cell migration assay, C3aR loss-of-function (morpholino knockdown), rescue with recombinant C3a, live imaging of collective migration |
Developmental cell |
High |
22118769
|
| 2007 |
C5L2 (GPR77) functions as a positive modulator of both C5a- and C3a-induced signaling in neutrophils, macrophages, and fibroblasts; C5L2-deficient mice phenocopy C3aR-deficient mice in hypersensitivity to LPS-induced septic shock and reduced OVA-induced airway hyper-responsiveness. |
Gene targeting (C5L2 knockout), in vitro C3a/C5a signaling assays in primary cells, LPS challenge model, OVA airway model |
Nature |
High |
17322907
|
| 2003 |
Normal human CD34+ hematopoietic stem/progenitor cells express functional C3aR and respond to C3a with calcium flux; C3a potentiates SDF-1 (CXCL12)-dependent chemotaxis, trans-Matrigel migration, MMP-9 secretion, and VLA-4-mediated adhesion to VCAM-1; bone marrow stroma secretes C3; C3a-primed murine Sca-1+ cells engraft faster in vivo. |
Flow cytometry (C3aR expression), calcium flux assay, transwell chemotaxis assay, trans-Matrigel migration, MMP-9 ELISA, VCAM-1 adhesion assay, in vivo engraftment model |
Blood |
High |
12511407
|
| 2002 |
C3a and C5a induce distinct signal transduction cascades in endothelial cells: C3aR activation causes transient actin stress fiber formation via Rho (G-alpha12/13-dependent, pertussis toxin-insensitive); C5aR activation causes delayed cytoskeletal retraction and increased paracellular permeability via PI3K/src/EGFR transactivation (pertussis toxin-sensitive). |
Actin stress fiber assay, pertussis toxin inhibition, rho activation assay, paracellular permeability assay, EGFR phosphorylation immunoprecipitation, pharmacological inhibitors (PI3K, src, EGFR) |
Journal of immunology |
Medium |
12165538
|
| 2012 |
The aHUS-associated C3 mutation R139W creates a hyperactive C3 convertase; mutant C3 shows increased affinity for factor B and reduced binding to MCP (CD46) but normal regulation by factor H, leading to increased C3 deposition and C5a release on inflamed glomerular endothelial cells. |
C3 deposition and C5a ELISA on glomerular endothelial cells, SPR binding assays for factor B, MCP, factor H interactions, C3 convertase activity assay with mutant vs wild-type C3 |
Blood |
High |
22246034
|
| 2008 |
Factor H contains distinct binding sites for C3b and glycosaminoglycans: CCP 1–4 (Kd ~14 µM) and CCPs 19–20 (Kd ~3.5 µM) bind C3b; CCPs 7–8 and 19–20 bind heparin; previously reported CCPs 8–9, 12–13 heparin-binding activity was artifactual; none of CCPs 9–15 show significant C3b binding. |
Recombinant CCP module expression, heparin-affinity chromatography, gel-mobility shift assays, SPR (surface plasmon resonance) with C3b on CM5 and C1 chips |
Journal of immunology |
High |
18684951
|
| 1996 |
C3a modulates LPS-induced TNF-alpha and IL-1beta synthesis in PBMCs in a cell-context-dependent manner: C3a suppresses cytokine production in non-adherent (circulating) PBMCs but enhances it in adherent (tissue-resident) PBMCs at the mRNA level; these effects are independent of PGE2 and are shared by C3a desArg. |
PBMC culture (adherent vs non-adherent), ELISA for TNF-alpha/IL-1beta, Northern blot for mRNA, indomethacin PGE2 blockade |
Journal of immunology |
Medium |
8617973
|
| 1999 |
HK-2 proximal tubular cells produce C3a, C3, and factors B and H via the alternative complement pathway; locally generated C3a signals back through the C3aR on HK-2 cells via a pertussis toxin-sensitive (Gi) pathway, inducing inositol phosphate production, tyrosine phosphorylation of at least two proteins, and TGF-beta1 secretion. |
RT-PCR for alternative pathway mRNAs, Western blot for secreted C3a, C3a RIA, inositol phosphate assay, pertussis toxin inhibition, TGF-beta1 ELISA, tyrosine phosphorylation Western blot |
Kidney international |
Medium |
10571781
|
| 1999 |
C3a(desArg) does not bind to the C3a receptor and does not signal through it; recombinant C3a binds C3aR with half-maximal concentration ~3 nM while rC3a(desArg) shows no detectable binding; C3aR-expressing RBL-2H3 transfectants respond to C3a but not C3a(desArg) for enzyme release and chemotaxis. |
Flow cytometry binding assay on C3aR-transfected RBL-2H3 cells with His-tagged ligands, N-acetyl-beta-D-glucosaminidase release assay, Boyden chamber chemotaxis assay |
Immunology letters |
High |
10232396
|
| 2012 |
Human C3a and C3a desArg have conserved three-dimensional structures (crystal structures at 2.3 and 2.6 Å, respectively) with no significant conformational differences, in contrast to C5a/C5a desArg; the loss of C3aR signaling by C3a desArg is therefore not due to a conformational change upon C-terminal arginine removal. |
Recombinant protein expression and purification, X-ray crystallography at 2.3 Å (C3a) and 2.6 Å (C3a desArg) |
Protein science |
High |
23184394
|
| 1998 |
C3a enhances LPS-induced NF-κB and AP-1 binding and IL-6 synthesis in adherent PBMCs while suppressing it in non-adherent PBMCs; both effects are mediated through a Gi protein-coupled pathway (blocked by pertussis toxin) and are independent of PGE2; C3a desArg shares these immunomodulatory effects. |
NF-κB/AP-1 gel mobility shift assay, IL-6 ELISA and Northern blot, pertussis toxin inhibition, indomethacin control |
Journal of immunology |
Medium |
9886419
|
| 2012 |
S. aureus proteins Sbi and Efb simultaneously bind C3/C3b and plasminogen; bound plasminogen is converted to plasmin by staphylokinase or urokinase, which then degrades complement C3, C3b, and C3a; Sbi and Efb enhance plasmin-mediated C3/C3b cleavage by inducing conformational changes in C3/C3b. |
Co-immunoprecipitation/pulldown of Sbi/Efb with C3 and plasminogen, in vitro plasmin cleavage assay of C3/C3b, SDS-PAGE of degradation products |
PloS one |
Medium |
23071827
|
| 2010 |
C3a binds to RAGE (receptor for advanced glycation end products) with EC50 ~1.9 nM; CpG oligonucleotides also bind RAGE directly and form a ternary complex with C3a/RAGE, increasing binding affinity to EC50 ~70 pM; C3a synergizes with CpG to increase IFN-alpha production from PBMCs in a RAGE-dependent manner. |
ELISA binding assay, SPR, fluorescence anisotropy, neutralizing anti-RAGE antibody and soluble RAGE inhibition, IFN-alpha ELISA, RAGE-/- mouse bone marrow cell assay |
Journal of immunology |
Medium |
20817881
|
| 2013 |
Human T cells and dendritic cells locally produce C3a and C5a during allogeneic responses; both cell types express C3aR and C5aR; C3aR/C5aR antagonists inhibit T cell proliferation; recombinant C3a promotes CD4+ T cell expansion and induces AKT phosphorylation; siRNA knockdown of DC C3 reduces T cell alloresponses; downregulation of DAF increases local C3a/C5a and augments T cell proliferation. |
C3a/C5a ELISA in T cell cultures, C3aR/C5aR antagonist treatment, recombinant C3a stimulation, AKT phosphorylation Western blot, siRNA knockdown of DC C3, DAF knockdown, in vivo GVHD NOD scid mouse model |
American journal of transplantation |
High |
24033923
|
| 2009 |
C3a mediates epithelial-to-mesenchymal transition (EMT) in tubular epithelial cells; C3a exposure reduces E-cadherin and increases alpha-smooth muscle actin and collagen I expression; C3aR antagonist blocks both C3a-induced and serum-induced EMT; C3aR-deficient mice show less renal interstitial fibrosis in the adriamycin nephropathy model. |
In vitro C3a stimulation of tubular cells, E-cadherin/alpha-SMA/collagen I expression by Western blot and qPCR, C3aR antagonist (SB290157), C3aR-/- mice in adriamycin nephropathy model |
Journal of the American Society of Nephrology |
High |
19158354
|
| 2016 |
C3a/C3aR signaling stimulates post-ischemic neural plasticity; C3a overexpression in astrocytes increases GAP43 expression (axonal sprouting marker) post-stroke; C3aR deficiency decreases GAP43; intranasal C3a treatment starting 7 days post-stroke increases synaptic density, GAP43, and accelerates functional recovery of forepaw motor function. |
Photothrombotic stroke model, C3aR-/- and GFAP-C3a transgenic mice, GAP43 immunostaining, synaptic density quantification, forepaw motor function behavioral testing, intranasal C3a administration |
Brain |
High |
27956400
|
| 2017 |
Complement C3a signals via C3aR to regulate monocyte/macrophage recruitment during skeletal muscle regeneration; C3a/C3aR deficiency reduces expression of adhesion molecules, cytokines, and antigen-processing genes in monocytes; exogenous CCL5 rescues the recruitment defect in C3aR-deficient mice; the alternative pathway component Cfb is required upstream. |
Cardiotoxin-induced muscle injury model, C3-/-, Cfb-/-, C3aR-/- mice, monocyte gene expression profiling, immunohistochemistry for macrophage infiltration, recombinant CCL5 rescue experiment |
Nature communications |
High |
29233958
|
| 2019 |
C3-dependent microglial clearance via CR3 (iC3b receptor) protects photoreceptors in retinitis pigmentosa; C3 activation localizes to activated microglia; genetic ablation of C3 or CR3 reduces microglial phagocytosis of apoptotic photoreceptors, increases microglial neurotoxicity, and accelerates photoreceptor degeneration. |
rd10 mouse model, C3-/- and CR3-/- genetic ablation, immunohistochemistry for complement components and microglia markers, photoreceptor degeneration quantification, microglial phagocytosis assay |
The Journal of experimental medicine |
High |
31209071
|
| 2021 |
The Sez6 family (Sez6, Sez6L, Sez6L2) inhibits complement by: (1) accelerating C3 convertase dissociation (decay-accelerating activity) and (2) serving as cofactors for Factor I to cleave C3b; Sez6L2 has no cofactor activity for C4b; these activities specifically reduce C3b/iC3b opsonization via both classical and alternative pathways. |
Complement opsonization assay (C3b/iC3b deposition), convertase decay assay, Factor I cofactor assay with C3b and C4b substrates, SDS-PAGE of cleavage products |
Frontiers in immunology |
High |
33936031
|
| 2005 |
C3a enhances CXCL12-induced chemotaxis of hematopoietic progenitor cells independently of the classical C3aR; C3a-desArg and C4a (but not C5a) share this activity; C3a directly interacts with CXCL12 and increases its binding affinity to CXCR4 on C3aR-negative cells; C3aR knockout BM cells respond normally to C3a/CXCL12 enhancement. |
Transwell chemotaxis assay, C3aR flow cytometry, SB290157 C3aR antagonist, C3aR-/- mouse BM cells, CXCL12-binding assay on CXCR4+/C3aR- REH cells |
Journal of immunology |
Medium |
16148115
|
| 2005 |
The C3aR antagonist SB 290157 has full agonist activity on C3aR in multiple assay systems (calcium mobilization in C3aR-transfected RBL cells, beta-lactamase reporter in CHO-NFAT-bla cells, enzyme release from U-937 cells), but lacks agonist activity in cells expressing C3aR at very low levels (guinea pig platelets); results attributed to C3aR antagonism by SB 290157 in the literature may reflect agonist effects. |
Calcium mobilization assay in transfected RBL cells, beta-lactamase reporter assay in CHO-NFAT-bla cells, enzyme release from differentiated U-937 cells, guinea pig platelet assay |
Immunology letters |
Medium |
16154494
|
| 2014 |
Cigarette smoke-induced neutrophil elastase cleaves C3 to release C3a, which increases C3aR expression on lung myeloid dendritic cells via autocrine/paracrine signaling; C3-/- and C3aR-/- mice develop less emphysema and have fewer lung mDC infiltrates after chronic smoke exposure. |
Chronic cigarette smoke model, C3-/- and C3aR-/- mice, neutrophil elastase C3 cleavage assay, lung mDC quantification, immunostaining for C3 deposits in human smoker tissue |
Mucosal immunology |
Medium |
25465103
|
| 2022 |
C3a/C3aR activation induces podocyte injury in primary membranous nephropathy; C3aR blockade in Heymann nephritis rats reduces proteinuria, foot process effacement, and glomerular basement membrane thickening; human podocytes exposed to MN plasma show C3aR-dependent increases in PLA2R, Wnt3/β-catenin, and decreases in synaptopodin. |
Heymann nephritis rat model with C3aR antagonists (SB290157, JR14a), electron microscopy, proteinuria measurement, human podocyte in vitro stimulation with MN plasma, C3aR immunostaining |
Journal of the American Society of Nephrology |
High |
35777783
|
| 2020 |
C3a/C3aR signaling induces mitochondrial fragmentation and dysfunction in podocytes via cAMP-dependent mechanisms; C3aR blockade normalizes mitochondrial morphology, SOD2 expression, and energetic metabolism and preserves podocyte density in diabetic nephropathy (BTBR ob/ob) mice. |
BTBR ob/ob mouse model with C3aR antagonist, electron microscopy of podocyte mitochondria, cAMP assay, SOD2 Western blot, in vitro podocyte C3a stimulation, mitochondrial membrane potential assay, SS-31 mitochondrial protector rescue |
JCI insight |
High |
32161193
|
| 2022 |
The C3-complement factor D (Cfd)-C3aR axis drives right ventricular failure; C3 knockout attenuates right ventricular dysfunction and fibrosis; C3a is generated by the Cfd-containing C3 convertase complex; Cfd knockout also attenuates RV failure; C3aR antagonist dramatically improves right ventricular dysfunction in mice. |
Pulmonary artery banding mouse model, C3-/- mice, Cfd-/- mice, C3aR antagonist treatment, echocardiography, histological fibrosis quantification |
Nature communications |
High |
36109509
|
| 2023 |
SARS-CoV-2 spike protein S1 activates the C3/C3aR pathway in lung endothelium in vivo; S1 injection in ACE2-transgenic mice induces C3 deposits, increased C3aR expression, thrombomodulin loss, and vWF increase followed by fibrin/platelet aggregates and fibrosis; C3aR antagonist inhibits lung C3 accumulation and limits thrombo-inflammation. |
S1 injection in hACE2 transgenic mice, C3aR antagonist treatment, immunofluorescence for C3/C3aR/thrombomodulin/vWF, lung histopathology |
Scientific reports |
Medium |
37452090
|
| 1996 |
Adipose tissue activates the alternative complement pathway through local expression of C3, factor B, and adipsin/factor D, generating C3a/ASP (acylation stimulating protein); complement activation regulatory genes Crry and factor H are downregulated during adipocyte differentiation; plasma C3a levels correlate with plasma triglyceride levels in lean mice. |
RT-PCR for complement regulatory genes in preadipocytes vs adipocytes, murine C3a/ASP radioimmunoassay in lean vs obese mice, triglyceride correlation analysis |
Obesity research |
Medium |
8946437
|
| 2019 |
C3a promotes versican V1 transcription in tubular cells via the AKT/β-catenin pathway; C3aR knockout in mice decreases versican expression in adriamycin nephropathy; tubular cell-derived versican V1 activates fibroblasts via CD44/Smad3 pathway; C3aR and suPAR/integrin β6 cooperate to increase versican V1 through transcriptional and splicing mechanisms respectively. |
C3a stimulation of tubular cells, AKT/β-catenin Western blot, C3aR-/- mice in ADR model, versican V1 quantification by qPCR/IHC, fibroblast co-culture assay |
JCI insight |
Medium |
30944246
|
| 2006 |
C3a-derived peptides (including CNY21, residues Cys57-Arg77 of C3a) have antifungal activity against Candida by binding to cell surfaces and inducing membrane perturbations; arginine residues are critical for this antimicrobial activity; Candida infection induces complement degradation leading to C3a generation. |
Fluorescence and electron microscopy of Candida-peptide interactions, minimal inhibitory concentration assay, arginine-substitution variants, complement degradation assay in Candida-exposed serum |
Biochimica et biophysica acta |
Medium |
17169328
|
| 2009 |
C3a and C5a sensitize cutaneous nociceptors: both fragments lower heat response thresholds and increase action potential firing in C-nociceptors; A-nociceptors are activated; C5aR mRNA is expressed in dorsal root ganglia; C3a and C5a elevate intracellular Ca2+ in DRG neurons and facilitate capsaicin-induced Ca2+ responses. |
In vivo intraplantar injection hyperalgesia model, skin-nerve in vitro preparation for nociceptor recording, DRG RT-PCR for C5aR, Ca2+ imaging in DRG neurons |
Pain |
Medium |
20031321
|
| 2013 |
Normal Th1 induction in human T cells requires T cell-derived C3a and C3aR signaling; C3-deficient patient T cells show impaired Th1 but intact Th2 responses in vitro, phenocopying CD46-deficient patients; C3-deficient CD4+ T cells have reduced CD25 and CD122 expression, linking complement-derived C3a to IL-2 receptor assembly. |
T cells from C3-deficient patients, cytokine ELISA/FACS for IFN-gamma (Th1) and IL-4 (Th2), CD25/CD122 surface expression by flow cytometry |
Molecular immunology |
Medium |
24321396
|