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 …

Complement Component 3 expressed by the endometrial ectopic tissue is involved in the endometriotic lesion formation through mast cell activation

AbstractThe pathophysiology of endometriosis (EM) is an excellent example of immune dysfunction, reminiscent of tumor microenvironment as well. Here, we report that an interplay between C3 and mast cells (MCs) is involved in the pathogenesis of ectopic EM. C3 is at the epicenter of the regulatory feed forward loop, amplifying the inflammatory microenvironment, in which the MCs are protagonists. Thus, C3 can be considered a marker of EM and its local synthesis can promote the engraftment of the endometriotic cysts. We generated a murine model of EM via injection of minced uterine tissue from a donor mouse, into the peritoneum of the recipient mice. The wild type mice showed greater amount of…

C1q acts in the tumour microenvironment as a cancer-promoting factor independently of complement activation

Complement C1q is the activator of the classical pathway. However, it is now recognized that C1q can exert functions unrelated to complement activation. Here we show that C1q, but not C4, is expressed in the stroma and vascular endothelium of several human malignant tumours. Compared with wild-type (WT) or C3- or C5-deficient mice, C1q-deficient (C1qa−/−) mice bearing a syngeneic B16 melanoma exhibit a slower tumour growth and prolonged survival. This effect is not attributable to differences in the tumour-infiltrating immune cells. Tumours developing in WT mice display early deposition of C1q, higher vascular density and an increase in the number of lung metastases compared with C1qa−/− mi…

Targeted tumor imaging of anti-CD20-polymeric nanoparticles developed for the diagnosis of B-cell malignancies

Sara Capolla,1 Chiara Garrovo,2 Sonia Zorzet,1 Andrea Lorenzon,3 Enrico Rampazzo,4 Ruben Spretz,5 Gabriele Pozzato,6 Luis Núñez,7 Claudio Tripodo,8 Paolo Macor,1,9 Stefania Biffi2 1Department of Life Sciences, University of Trieste, 2Institute for Maternal and Child Health – IRCCS “Burlo Garofolo”, Trieste, 3Animal Care Unit, Cluster in Biomedicine (CBM scrl), Trieste, Italy; 4Department of Chemistry “G. Ciamician”, University of Bologna, Bologna, Italy; 5LNK Chemsolutions LLC, Lincoln, NE, USA; 6Department of Medical, Surgery and Health Sciences, University of Trieste, Trieste, Italy; 7Bio-Target, Inc., University of C…

Selection and characterization of a novel agonistic human recombinant anti-Trail-R2 minibody with anti-leukemic activity

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising natural anticancer therapeutic agent because through its “death receptors”, TRAIL-R1 and TRAIL-R2, it induces apoptosis in many transformed tumor cells, but not in the majority of normal cells. Hence, agonistic compounds directed against TRAIL death receptors have the potential of being excellent cancer therapeutic agents, with minimal cytotoxicity in normal tissues. Here, we report the selection and characterization of a new single-chain fragment variable (scFv) to TRAIL-R2 receptor isolated from a human phage-display library, produced as minibody (MB), and characterized for the in vitro anti-leukemic tumoricid…

The Inflammatory Feed-Forward Loop Triggered by the Complement Component C3 as a Potential Target in Endometriosis

Copyright © 2021 Agostinis, Zorzet, Balduit, Zito, Mangogna, Macor, Romano, Toffoli, Belmonte, Morello, Martorana, Borelli, Ricci, Kishore and Bulla. The complement system is a major component of humoral innate immunity, acting as a first line of defense against microbes via opsonization and lysis of pathogens. However, novel roles of the complement system in inflammatory and immunological processes, including in cancer, are emerging. Endometriosis (EM), a benign disease characterized by ectopic endometrial implants, shows certain unique features of cancer, such as the capacity to invade surrounding tissues, and in severe cases, metastatic properties. A defective immune surveillance against…

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…

New Potential Therapeutic Approach for the Treatment of B-Cell Malignancies Using Chlorambucil/Hydroxychloroquine-Loaded Anti-CD20 Nanoparticles

Current B-cell disorder treatments take advantage of dose-intensive chemotherapy regimens and immunotherapy via use of monoclonal antibodies. Unfortunately, they may lead to insufficient tumor distribution of therapeutic agents, and often cause adverse effects on patients. In this contribution, we propose a novel therapeutic approach in which relatively high doses of Hydroxychloroquine and Chlorambucil were loaded into biodegradable nanoparticles coated with an anti-CD20 antibody. We demonstrate their ability to effectively target and internalize in tumor B-cells. Moreover, these nanoparticles were able to kill not only p53 mutated/deleted lymphoma cell lines expressing a low amount of CD20…

Development of a human-SCID lymphoma as a model to evaluate the therapeutic effect of Rituximab

New Therapeutic Approach for the Treatment of B-Cell Disorders Using Chlorambucil/Hydroxychloroquine-Loaded AntiCD20 Nanoparticles

Abstract Abstract 158 B-cell disorders show highly variable clinical courses, ranging between indolent diseases like the chronic lymphocytic leukemia (CLL) and highly aggressive lymphoproliferative disorders like Burkitt Lymphoma. The treatments of these disorders have been characterized by the development of new approaches, including dose-intensive chemotherapy regimens and immunotherapy via monoclonal antibodies (Ab). Despite the promising survival rates, these multi-agent treatments are flawed by a high degree of toxicity and a significant fraction of patients do not respond. The use of core shell nanoparticles design with specific Ab-coating represents a new strategy to target only tumo…

Bispecific antibodies targeting tumor-associated antigens and neutralizing complement regulators increase the efficacy of antibody-based immunotherapy in mice.

The efficacy of antibody-based immunotherapy is due to the activation of apoptosis, the engagement of antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity (CDC). We developed a novel strategy to enhance CDC using bispecific antibodies (bsAbs) that neutralize the C-regulators CD55 and CD59 to enhance C-mediated functions. Two bsAbs (MB20/55 and MB20/59) were designed to recognize CD20 on one side. The other side neutralizes CD55 or CD59. Analysis of CDC revealed that bsAbs could kill 4-25 times more cells than anti-CD20 recombinant antibody in cell lines or cells isolated from patients with chronic lymphocytic leukemia. The pharmacokinetics of the bsAbs was evaluate…

C1q secreted in the tumour microenvironment promotes tumour growth in the absence of complement activation

We have recently shown that locally secreted C1q is involved in trophoblast invasion of decidua during pregnancy (Agostinis et al., J. Immunol. 2010;185;4420–4429). Since this physiologic process resembles to some extent tumor progression, we sought to investigate if C1q plays a similar role in tumor development and progression. Immunohistochemical analysis of several solid tumours including colon, prostate, lung and breast cancer and melanoma revealed the presence of C1q that was localized on the vascular endothelium and also distributed in the stroma in the absence of C4. To investigate the in vivo role of C1q in tumour development, 6/8 week old female WT and C1q−/− C57BL/6 mice received …

Neutralizing human antibodies against CD55 and CD59 targeted to lymphoma cells in vivo potentiate the therapeutic effect of Rituximab

An update on the xenograft and mouse models suitable for investigating new therapeutic compounds for the treatment of B-cell malignancies

B-cell malignancies account for over the 90% of all lymphoid neoplasms. The clonal proliferations of B-cells show a high degree of variation in terms of clinical and presenting features, histopathology, immuophenotype, and genetics. Primary tumor samples are useful for examining the characteristics of a patients own tumor, although both primary leukemic cells and cell lines provide an initial step for screening novel compounds for their activity in some hematological malignancies, they should be followed by models in intact animals. In this review, we try to summarize the animal models generated to study B-cell malignancies, in particular, B-cell lymphoma, B-cell CLL and MM that represent t…

Human bone marrow mesenchymal stem cells display anti-cancer activity in SCID mice bearing disseminated non-Hodgkin's lymphoma xenografts.

Background Although multimodality treatment can induce high rate of remission in many subtypes of non-Hodgkin's lymphoma (NHL), significant proportions of patients relapse with incurable disease. The effect of human bone marrow (BM) mesenchymal stem cells (MSC) on tumor cell growth is controversial, and no specific information is available on the effect of BM-MSC on NHL. Methodology/Principal Findings The effect of BM-MSC was analyzed in two in vivo models of disseminated non-Hodgkin's lymphomas with an indolent (EBV− Burkitt-type BJAB, median survival = 46 days) and an aggressive (EBV+ B lymphoblastoid SKW6.4, median survival = 27 days) behavior in nude-SCID mice. Intra-peritoneal (i.p.) i…

In vivo biodistribution and lifetime analysis of cy5.5-conjugated rituximab in mice bearing lymphoid tumor xenograft using time-domain near-infrared optical imaging.

Rituximab is a chimeric monoclonal antibody directed against human CD20 antigen, which is expressed on B-cell lymphocytes and on the majority of B-cell lymphoid malignancies. Herein we report the conjugate of rituximab with the near-infrared (NIR) fluorophore Cy5.5 (RI-Cy5.5) as a tool for in vitro, in vivo, and ex vivo NIR time-domain (TD) optical imaging. In vitro, RI-Cy5.5 retained biologic activity and led to elevated cell-associated fluorescence on tumor cells. In vivo, TD optical imaging analysis of RI-Cy5.5 injected into lymphoma-bearing mice revealed a slow tumor uptake and a specific long-lasting persistence of the probe within the tumor. Biodistribution studies after intraperiton…

A new approach for the treatment of CLL using chlorambucil/hydroxychloroquine-loaded anti-CD20 nanoparticles

Current approaches for the treatment of chronic lymphocytic leukemia (CLL) have greatly improved the prognosis for survival, but some patients remain refractive to these therapeutic regimens. Hence, in addition to reducing the long-term sideeffects of therapeutics for all leukemia patients, there is an urgent need for novel therapeutic strategies for difficult-to-treat leukemia cases. Due to the cytotoxicity of drugs, the major challenge currently is to deliver the therapeutic agents to neoplastic cells while preserving the viability of non-malignant cells. In this study, we propose a therapeutic approach in which high doses of hydroxychloroquine and chlorambucil were loaded into biodegrada…

Exploratory study on the effects of biodegradable nanoparticles with drugs on malignant B cells and on a human/mouse model of Burkitt lymphoma.

The aim of this study was to determine if Rituximab coated Biodegradable Nanoparticles (BNPs) loaded with Chlorambucil and Hydroxychloroquine could induce apoptosis of B-Chronic Lymphocytic Leukemia (B-CLL), MEC-1 and BJAB cells in vitro and evaluate their toxic and therapeutic effects on a Human/Mouse Model of Burkitt Lymphoma at an exploratory, proof of concept scale. We found that Rituximab-Chlorambucil-Hydroxychloroquine BNPs induce a decrease in cell viability of malignant B cells in a dose-dependent manner. The mediated cytotoxicity resulted from apoptosis, and was confirmed by monitoring the B-CLL cells after Annexin V/propidium iodide staining. Additional data revealed that these BN…