Complement C1q and C8beta deficiency in an individual with recurrent bacterial meningitis and adult-onset systemic lupus erythematosus-like illness.

Co-existing complement C8 deficiency ameliorated the SLE associated with C1q deficiency.

Protective and regenerative effects of a novel medical device against esophageal mucosal damage using in vitro and ex vivo models.

Gastroesophageal reflux disease (GERD) is a common digestive disorder that causes esophagitis and injuries to the esophageal mucosa. GERD symptoms are recurrent during pregnancy and their treatment is focused on lifestyle changes and nonprescription medicines. The aim of this study was to characterize the mechanism of action of a new patented medical device, an oral formulation containing hyaluronic acid, rice extract, and amino acids dispersed in a bioadhesive polymer matrix, by assessing its protective effects in in vitro and ex vivo models of esophageal mucosa damage. Acidic bile salts and pepsin cocktail (BSC) added to CP-A and COLO-680 N esophagus cells were used as an in vitro GERD mo…

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

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 …

C1q induces in vivo angiogenesis and promotes wound healing

Mutant p53 induces Golgi tubulo-vesiculation driving a prometastatic secretome

TP53 missense mutations leading to the expression of mutant p53 oncoproteins are frequent driver events during tumorigenesis. p53 mutants promote tumor growth, metastasis and chemoresistance by affecting fundamental cellular pathways and functions. Here, we demonstrate that p53 mutants modify structure and function of the Golgi apparatus, culminating in the increased release of a pro-malignant secretome by tumor cells and primary fibroblasts from patients with Li-Fraumeni cancer predisposition syndrome. Mechanistically, interacting with the hypoxia responsive factor HIF1α, mutant p53 induces the expression of miR-30d, which in turn causes tubulo-vesiculation of the Golgi apparatus, leading …

An alternative role of C1q in cell migration and tissue remodeling: contribution to trophoblast invasion and placental development.

Abstract Fetal trophoblast cells invading the decidua in the early phase of pregnancy establish complex interaction with the maternal extracellular matrix. We discovered that C1q was widely distributed in human decidual stroma in the absence of C4 and C3 and was actively synthesized by migrating extravillous trophoblasts. The cells expressed the messages for the three chains of C1q and secreted this complement component that interacted with the proteins of the decidual extracellular matrix. Solid phase-bound C1q promoted trophoblast adhesion and migration, and cell binding to C1q resulted in activation of ERK1/2 MAPKs. Ab inhibition experiments showed that the receptors for the globular hea…

In vivo targeting of human neutralizing antibodies against CD55 and CD59 to lymphoma cells increases the antitumor activity of rituximab.

AbstractAn in vivo model of human CD20+ B-lymphoma was established in severe combined immunodeficiency mice to test the ability of human neutralizing miniantibodies to CD55 and CD59 (MB55 and MB59) to enhance the therapeutic effect of rituximab. The miniantibodies contained single-chain fragment variables and the hinge-CH2-CH3 domains of human IgG1. LCL2 cells were selected for the in vivo study among six B-lymphoma cell lines for their high susceptibility to rituximab-dependent complement-mediated killing enhanced by MB55 and MB59. The cells injected i.p. primarily colonized the liver and spleen, leading to the death of the animals within 30 to 40 days. Thirty percent of mice receiving bio…

ABSTRACTS: 9
Phenotype characterization of the anti-inflammatory behavior of decidual endothelial cells

Problem:  During pregnancy, an adequate inflammatory control is essential for normal intrauterine foetus development. Vascular endothelium is known to play a critical role in regulation of inflammatory processes. We hypothesize a different ability of decidual endothelial cells (DEC) compared to endothelium from other districts to respond to inflammatory stimuli. Material and Methods:  DEC were isolated and activated with inflammatory stimuli and their response in term of adhesion molecules expression, vascular leakage and cytokines production was evaluated. These data were compared to the data obtained with HUVEC and microvascular endothelial cells isolated from human skin (ADMEC) and from …

Phenotype characterization of the anti-inflammatory behavior of decidual endothelial cells

C1q is involved in human trophoblast invasion

During the development of human placenta, extravillous trophoblast (EVT) departs from anchoring chorionic villi and invades the maternal decidua. Immunohistochemical analysis of decidua obtained from voluntary abortions showed that C1q was widely distributed in the decidual stroma with intense staining around invading trophoblast, while undetectable in non pregnant uterus. Based on these findings, we hypothesized that C1q may be involved in the migration of EVT. To this end, we investigated the ability of EVT to adhere to solid-phase bound C1q and to migrate using a transwell model system with inserts coated with C1q. Our results showed that EVT strongly adhered to C1q to an extent similar …

Decidual endothelial cells express surface-bound C1q as a molecular bridge between endovascular trophoblast and decidual endothelium.

This study was prompted by the observation that decidual endothelial cells (DECs), unlike endothelial cells (ECs) of blood vessels in normal skin, kidney glomeruli and brain, express surface-bound C1q in physiologic pregnancy. This finding was unexpected, because deposits of C1q are usually observed in pathologic conditions and are associated with complement activation. In the case of DECs, we failed to detect immunoglobulins and C4 co-localized with C1q on the cell surface. Surprisingly, DECs expressed mRNA for the three chains of C1q and secreted detectable level of this component in serum-free medium. The ability to synthesize C1q is acquired by DECs during pregnancy and is not shared by…

C7 is expressed on endothelial cells as a trap for the assembling terminal complement complex and may exert anti-inflammatory function.

AbstractWe describe a novel localization of C7 as a membrane-bound molecule on endothelial cells (ECs). Data obtained by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), Western blot analysis, Northern blot analysis, and mass spectrometry revealed that membrane-associated C7 (mC7) was indistinguishable from soluble C7 and was associated with vimentin on the cell surface. mC7 interacted with the other late complement components to form membrane-bound TCC (mTCC). Unlike the soluble SC5b-9, mTCC failed to stimulate ECs to express adhesion molecules, to secrete IL-8, and to induce albumin leakage through a monolayer of ECs, and more importantly protected ECs from the proinf…

The soluble terminal complement complex (SC5b-9) up-regulates osteoprotegerin expression and release by endothelial cells: Implications in rheumatoid arthritis

Objective. Complement activation products contribute to a large number of inflammatory diseases, including RA. We have investigated whether osteoprotegerin (OPG) may concur with the soluble terminal complement complex (SC5b-9) to the inflammatory cascade characterizing RA. Methods. Levels of SC5b-9 and OPG in the plasma and SF of patients with active RA were determined by ELISA. The presence of SC5b-9 and OPG in RA synovial lesions was analysed by immunohistochemistry. Cultured endothelial cells were used for in vitro leucocyte/endothelial cell adhesion assays. In addition, endothelial cells were exposed to SC5b-9 in order to evaluate the effects on the production of OPG protein, as well as…

CCL3 and CCL4, the Major Chemokines Produced by CD38+ Chronic Lymphocytic Leukemia Cells, Facilitate Microenvironmental Interactions of Neoplastic Cells Via the CD49d/VCAM Pair.

Abstract CD38, a negative prognostic marker for patients with CLL, has been demonstrated to be a key molecule in the interactions occurring in the context of tumor microenvironment, mediating both survival and migratory signals for CLL cells. By taking advantage of gene expression profiling studies (GEP) comparing 11 CD38pos (CD38>30%) and 15 CD38neg (CD38<10%) CLLs, we identified as over-expressed in CD38pos CLL cells: i) genes for the two C-C chemokines CCL3 and CCL4 (median-log difference, MLD-CCL3= 3.5; MLD-CCL4=4.4); real-time quantitative PCR (RTQ-PCR) of selected cases confirmed GEP results; ii) the gene for CD49d (MLD=4.4); a high correlation between CD38 and CD49d pro…

Monocytes/Macrophages Are the Major Targets of the CCL3 Chemokine Produced by CD38(+)CD49d(+) Chronic Lymphocytic Leukemia Cells

Abstract Abstract 2350 Poster Board II-327 Introduction: CD38 and CD49d are associated negative prognosticators in chronic lymphocytic leukemia (CLL). Recent gene expression profiling studies comparing CLL cases expressing low versus high levels of CD38 and CD49d, identified CCL3 as a gene upregulated by CD38+CD49d+ CLL. The release of CCL3 by cultured CLL cells was also demonstrated upon CD38 triggering, and CCL3 protein was found in CLL cells from bone marrow biopsies (BMB) of CD38+ cases (Zucchetto et al., Cancer Res, 2009; 69:4001-9). Given the role of CCL3 as potent chemoattractant for different cell types, we aimed at identifying the major targets of CCL3, as produced by CD38+CD49d+ C…

CD38/CD31, the CCL3 and CCL4 chemokines, and CD49d/vascular cell adhesion molecule-1 are interchained by sequential events sustaining chronic lymphocytic leukemia cell survival.

AbstractCD38 and CD49d are associated negative prognosticators in chronic lymphocytic leukemia (CLL). Despite evidence that both molecules are involved in interactions occurring between CLL and normal cells in the context of CLL-involved tissues, a functional link is still missing. Using gene expression profiles comparing CD38+CD49d+ versus CD38−CD49d− CLL cells, we showed overexpression of the CCL3 and CCL4 chemokines in cells from the former group. These chemokines were also up-regulated by CD38 signals in CLL; moreover, CCL3 was expressed by CLL cells from bone marrow biopsies (BMB) of CD38+CD49d+ but not CD38−CD49d− cases. High levels of CCR1 and, to a lesser extent, CCR5, the receptors…