Showing papers by "Wolf H. Fridman published in 2005"

Effector Memory T Cells, Early Metastasis, and Survival in Colorectal Cancer

Abstract: Background The role of tumor-infiltrating immune cells in the early metastatic invasion of colorectal cancer is unknown. Methods We studied pathological signs of early metastatic invasion (venous emboli and lymphatic and perineural invasion) in 959 specimens of resected colorectal cancer. The local immune response within the tumor was studied by flow cytometry (39 tumors), low-density-array real-time polymerase-chain-reaction assay (75 tumors), and tissue microarrays (415 tumors). Results Univariate analysis showed significant differences in disease-free and overall survival according to the presence or absence of histologic signs of early metastatic invasion (P<0.001). Multivariate Cox analysis showed that an early conventional pathological tumor–node–metastasis stage (P<0.001) and the absence of early metastatic invasion (P=0.04) were independently associated with increased survival. As compared with tumors with signs of early metastatic invasion, tumors without such signs had increased infiltrates of i...

Anti–Factor H Autoantibodies Associated with Atypical Hemolytic Uremic Syndrome

Abstract: Several studies have demonstrated genetic predisposition in non-shigatoxin-associated hemolytic uremic syndrome (HUS), involving regulatory proteins of the complement alternative pathway: Factor H (FH) and membrane co-factor protein (CD46). Regarding the observations of thrombotic thrombocytopenic purpura patients, in whom a von Willebrand factor protease (ADAMST-13) deficiency may be inherited or acquired secondary to IgG antibodies, it was speculated that HUS might occur in a context of an autoimmune disease with the development of anti-FH antibodies leading to an acquired FH deficiency. The presence of FH autoantibodies was investigated by an ELISA method using coated purified human FH in a series of 48 children who presented with atypical HUS and were recruited from French university hospitals. Anti-FH IgG antibodies were detected in the plasma of three children who presented with recurrent HUS. The anti-FH specificity was conserved by the Fab'2 fraction. The plasma FH activity was found to be decreased, whereas plasma FH antigenic levels and FH gene analysis were normal, indicating that the presence of anti-FH antibodies led to an acquired functional FH deficiency. This report supports for the first time that HUS may occur in a context of an autoimmune disease with the development of anti-FH-specific antibody leading to an acquired FH deficiency. This new mechanism of functional FH deficiency may lead to the design of new approaches of diagnosis and treatment with a particular interest in plasma exchanges or immunosuppressive therapies.

CCL1-CCR8 interactions: an axis mediating the recruitment of T cells and Langerhans-type dendritic cells to sites of atopic skin inflammation.

Abstract: Atopic dermatitis represents a chronically relapsing skin disease with a steadily increasing prevalence of 10-20% in children. Skin-infiltrating T cells, dendritic cells (DC), and mast cells are thought to play a crucial role in its pathogenesis. We report that the expression of the CC chemokine CCL1 (I-309) is significantly and selectively up-regulated in atopic dermatitis in comparison to psoriasis, cutaneous lupus erythematosus, or normal skin. CCL1 serum levels of atopic dermatitis patients are significantly higher than levels in healthy individuals. DC, mast cells, and dermal endothelial cells are abundant sources of CCL1 during atopic skin inflammation and allergen challenge, and Staphylococcus aureus-derived products induce its production. In vitro, binding and cross-linking of IgE on mast cells resulted in a significant up-regulation of this inflammatory chemokine. Its specific receptor, CCR8, is expressed on a small subset of circulating T cells and is abundantly expressed on interstitial DC, Langerhans cells generated in vitro, and their monocytic precursors. Although DC maintain their CCR8+ status during maturation, brief activation of circulating T cells recruits CCR8 from intracytoplamic stores to the cell surface. Moreover, the inflammatory and atopy-associated chemokine CCL1 synergizes with the homeostatic chemokine CXCL12 (SDF-1alpha) resulting in the recruitment of T cell and Langerhans cell-like DC. Taken together, these findings suggest that the axis CCL1-CCR8 links adaptive and innate immune functions that play a role in the initiation and amplification of atopic skin inflammation.

Novel ganglioside antigen identified by B cells in human medullary breast carcinomas : The proof of principle concerning the tumor-infiltrating B lymphocytes

Abstract: The potential tumor-recognizing capacity of B cells infiltrating human breast carcinoma is an important aspect of breast cancer biology As an experimental system, we used human medullary breast carcinoma because of its heavy B lymphocytic infiltration paralleled to a relatively better prognosis Ig-rearranged V region VH-JH, Vκ-Jκ, and Vλ-Jλ genes, amplified by RT-PCR of the infiltrating B cells, were cloned, sequenced, and subjected to a comparative DNA analysis A combinatorial single-chain variable fragment Ab minilibrary was constructed out of randomly selected VH and Vκ clones and tested for binding activity Our data analysis revealed that some of the VH-JH, Vκ-Jκ, and Vλ-Jλ region sequences were being assigned to clusters with oligoclonal predominance, while other characteristics of the Ab repertoire were defined also A tumor-restricted binder clone could be selected out of the single-chain variable fragment κ minilibrary tested against membrane fractions of primary breast tumor cells and tumor cell lines, the VH of which proved to be the overexpressed VH3-1 cluster The specific binding was confirmed by FACS analysis with primary breast carcinoma cells and MDA-MB 231 cell line ELISA and thin layer chromatography dot-blot experiments showed this target Ag to be a ganglioside D3 (GD3) Our results are a proof of principle about the capacity of B cells infiltrating breast carcinomas to reveal key cancer-related Ags, such as the GD3 GD3-specific Abs may influence tumor cell progression and could be used for further development of diagnostic and/or therapeutic purposes

Dendritic Cell Precursors Are Permissive to Dengue Virus and Human Immunodeficiency Virus Infection

Abstract: CD14+ interstitial cells reside beneath the epidermis of skin and mucosal tissue and may therefore play an important role in viral infections and the shaping of an antiviral immune response. However, in contrast to dendritic cells (DC) or blood monocytes, these antigen-presenting cells (APC) have not been well studied. We have previously described long-lived CD14+ cells generated from CD34+ hematopoietic progenitors, which may represent model cells for interstitial CD14+ APC. Here, we show that these cells carry DC-SIGN and differentiate into immature DC in the presence of granulocyte-macrophage colony-stimulating factor. We have compared the CD14+ cells and the DC derived from these cells with respect to dengue virus and human immunodeficiency virus type 1 (HIV-1) infection. Both cell types are permissive to dengue virus infection, but the CD14+ cells secrete the anti-inflammatory cytokine interleukin 10 and no tumor necrosis factor alpha. Regarding HIV, the CD14+ cells are permissive to HIV-1, release higher p24 levels than the derived DC, and more efficiently activate HIV Pol-specific CD8+ memory T cells. The CD14+ DC precursors infected with either virus retain their DC differentiation potential. The results suggest that interstitial CD14+ APC may contribute to HIV-1 and dengue virus infection and the shaping of an antiviral immune response.

Dynamic interactions of Fc gamma receptor IIB with filamin-bound SHIP1 amplify filamentous actin-dependent negative regulation of Fc epsilon receptor I signaling.

Abstract: The engagement of high affinity receptors for IgE (FcepsilonRI) generates both positive and negative signals whose integration determines the intensity of mast cell responses. FcepsilonRI-positive signals are also negatively regulated by low affinity receptors for IgG (FcgammaRIIB). Although the constitutive negative regulation of FcepsilonRI signaling was shown to depend on the submembranous F-actin skeleton, the role of this compartment in FcgammaRIIB-dependent inhibition is unknown. We show in this study that the F-actin skeleton is essential for FcgammaRIIB-dependent negative regulation. It contains SHIP1, the phosphatase responsible for inhibition, which is constitutively associated with the actin-binding protein, filamin-1. After coaggregation, FcgammaRIIB and FcepsilonRI rapidly interact with the F-actin skeleton and engage SHIP1 and filamin-1. Later, filamin-1 and F-actin dissociate from FcR complexes, whereas SHIP1 remains associated with FcgammaRIIB. Based on these results, we propose a dynamic model in which the submembranous F-actin skeleton forms an inhibitory compartment where filamin-1 functions as a donor of SHIP1 for FcgammaRIIB, which concentrate this phosphatase in the vicinity of FcepsilonRI and thereby extinguish activation signals.

Neisseria meningitidis infection. Clinical criteria orienting towards a deficiency in the proteins of the complement

Abstract: Resume Objectif Les deficits en proteines de la voie finale commune du complement ou en proteines de la voie alterne sont rares mais augmentent considerablement le risque d’infection par Neisseria meningitidis. L’objectif de ce travail a ete de determiner les criteres cliniques de ce groupe a risque. Methodes Etude retrospective des donnees cliniques et biologiques de patients ayant un deficit en proteine du complement associe a une ou plusieurs infections a N. meningitidis. Resultats Quarante cas ont ete etudies, incluant 35 deficits en proteines de la voie finale commune, le deficit en C7 etant le plus frequent, 3 deficits en properdine et 2 deficits acquis en C3. Plus de 60 % des patients ont eu des infections recurrentes a N. meningitidis. Des souches de serogroupes rares ont ete isolees dans 50 % des cas. Les deficits en properdine etaient associes a une forme fulminante dans 2 cas sur 3. L’âge des premieres manifestations variait de 2 mois a 32 ans. Conclusion Un deficit doit etre systematiquement cherche pour tous les patients ayant une infection a N. meningitidis avant l’âge de 6 mois ou apres l’âge de 5 ans. L’identification des sujets deficitaires permet de proposer un depistage familial et une prophylaxie adaptee, incluant une vaccination preventive.

Fluorospot assay: methodological analysis.

Abstract: The conventional enzyme-linked immunospot (ELISPOT) technique detects only one secreted cytokine, which constitutes a major pitfall for the accurate characterization of the various T-cell subpopulations. We have therefore developed a fluorospot assay, which is a modification of the ELISPOT and is based on the use of multiple fluorescent-labeled anticytokines detection antibodies. A special automated ELISPOT reader consisting of a light microscope with incident fluorescence illumination and an integrating digital color camera has been adapted for this technique. This technique has been applied for the analysis of subpopulations of T-cells and polarized antigen-specific T-cells.