Search results for "c1q"

Expression of C1q, a subcomponent of the rat complement system, is dramatically enhanced in brains of rats with either Borna disease or experimental …

1995

In situ hybridization, RT-PCR and Northern blot analysis as well immunohistochemistry were used to examine the expression of C1q, a subcomponent of the rat complement system, in brains of rats infected with Borna disease virus (BDV) and rats afflicted with experimental allergic encephalomyelitis (EAE) induced by the adoptive transfer of myelin basic protein specific T cells. C1q mRNA, which was not detected in normal brain, became clearly detectable using RT-PCR analysis by d14 post infection (p.i.) with BDV. Maximal levels of C1q mRNA were reached 21 days p.i. when inflammatory reactions in the brain were also at a peak. Similarly, C1q mRNA was elevated when the clinical symptoms of EAE be…

C1q as a novel player in angiogenesis with therapeutic implication in wound healing

2014

We have previously shown that C1q is expressed on endothelial cells (ECs) of newly formed decidual tissue. Here we demonstrate that C1q is deposited in wound-healing skin in the absence of C4 and C3 and that C1q mRNA is locally expressed as revealed by real-time PCR and in situ hybridization. C1q was found to induce permeability of the EC monolayer, to stimulate EC proliferation and migration, and to promote tube formation and sprouting of new vessels in a rat aortic ring assay. Using a murine model of wound healing we observed that vessel formation was defective in C1qa(-/-) mice and was restored to normal after local application of C1q. The mean vessel density of wound-healing tissue and …

Expression of membrane C1q in human monocyte-derived macrophages is developmentally regulated and enhanced by interferon-γ

2001

The present study investigated when during "in vitro" maturation macrophages (MPhi) express membrane C1q (mC1q), and whether cell activation affects expression and function of mC1q. Although C1q mRNA was repeatedly detected in freshly isolated monocytes using reverse transcriptase-polymerase chain reaction, C1q protein was observed only in developing MPhi from day 1 to 4 on using immunodetection and flow cytometry. However, the quantity of mC1q and other MPhi membrane proteins differed strikingly in cells from different donors. We report here for the first time that CD14(+) and CD14(-) mC1q-bearing MPhi can develop, and that interferon-gamma increases mC1q display at the cell surface, and m…

Humoral autoreactivity directed against surfactant protein-A (SP-A) in rheumatoid arthritis synovial fluids.

2000

SUMMARY SP-A is found principally in the lung, and has been associated with lamellar bodies also found in the synovial joint. Both SP-A and C1q contain collagen-like regions, and SP-A and C1q have some structural similarities, both having a globular head region and a collagen-like tail. Here we are able to show that (i) autoreactivity to SP-A, as expressed by IgG and IgM autoantibodies, is present in synovial fluid (SF) isolated from patients with rheumatoid arthritis (RA); (ii) in absorption experiments only a limited degree of cross-reactivity between autoantibodies reactive with C1q and SP-A is observed; (iii) there is no cross-reactivity between autoantibodies reactive with type II coll…

Isolation, sequence analysis and characterization of cDNA clones coding for the C chain of mouse C1q. Sequence similarity of complement subcomponent …

1992

A mouse macrophage lambda gt11 cDNA library was screened using a genomic DNA clone coding for the C-chain gene of human C1q. Approximately 600,000 recombinant phage plaques were hybridized with peroxidase-labeled human C-chain probe and detected by enhanced chemiluminescence. Five positive clones were obtained. The size of the full-length cDNA is 1019 bp. The sequence identity of the nucleotide sequence with human C1q C chain is 79%, the identity of the deduced amino acid sequences is 73%. The mouse C1q C chain exhibits the same structural features as the human C chain, e.g. conservation of the cysteine residues. Like the mouse A chain, the mouse C chain has an RGD sequence that may be reco…

C1q Production by Bone Marrow Stromal Cells

2007

Autoreactivity to mouse C1q in a murine model of SLE.

1995

A large proportion of systemic lupus erythematosus (SLE) patients develop glomerulonephritis, coincident with the appearance of autoantibodies to C1q, the Fc-recognizing collagen-like subcomponent of the first component of complement, C1. The MRL/lpr/lpr mouse is an established model for SLE, developing both antinuclear and anti-type II collagen autoantibodies, and rheumatoid factors(s), exhibiting reduced complement levels and later on developing glomerulonephritis and often arthritis. We report here an age-dependent decrease in serum C1q levels coincident with the development of IgG2b autoantibodies reactive with mouse C1q in MRL/lpr/lpr mice. Unlike IgG2b, although high levels of IgM, Ig…

A longitudinal study of C1q and anti-C1q autoantibodies in homologous and heterologous pregnancies for predicting pre-eclampsia

2022

C1q, the recognition molecule of the classical pathway of the complement system, plays a central role in pregnancy. Lack of C1q is characterized by poor trophoblast invasion and pregnancy failure. C1q can be the target of an antibody response: anti‐C1q autoantibodies (anti-C1q) are present in several infectious and autoimmune diseases. The presence of these autoantibodies has been detected also in 2-8% of the general population. Recent evidence indicates that women who undergo assisted reproductive technology (ART) have an increased risk of developing pre-eclampsia (PE), particularly oocyte donation (OD) pregnancies. The aim of this study was to characterize the levels of C1q and anti-C1q i…

Arthritis-regulating determinants on the collagen-like complement component C1q

1992

Studies on the interaction of C1q,a subcomponent of the first component of complement, with porins fromSalmonella minnesotaincorporated into artifici…

1990

AbstractPurified outer membrane proteins (OMP) of Salmonella minnesota, Re-form, were incorporated into liposomes. These induced in macrophages a chemiluminescence signal identical to that of the intact Re-form. This signal was abolished by preincubation of porin-containing liposomes with purified C1q. Incorporation of isolated OMP into black lipid membranes (BLM) resulted in channel-formation which could not be inhibited by isolated C1q. Additionally, incubation of OMP-containing liposomes with BLM resulted in pore-formation within the BLM. This was amplified when lipid A was present within the liposomes. Preincubation of OMP-containing liposomes with purified C1q abolished pore-formation …