CD8 T cells mediate ultraviolet A-induced immunomodulation in a model of extracorporeal photochemotherapy.

Extracorporeal photochemotherapy (ECP) that takes advantage of the immunomodulatory effects of UV light has been extensively used for many years for the treatment of several T cell-mediated diseases, including graft-versus-host disease (GvHD) and systemic scleroderma. Immune mechanisms that lead to the establishment of T cell tolerance in ECP-treated patients remain poorly known. In this study, we have tested the effect of UV/psoralen-treated BM-derived dendritic cells, referred to as ECP-BMDCs on the outcome of an antigen-specific T cell-mediated reaction, that is, contact hypersensitivity (CHS), which is mediated by CD8 effector T cells (CD8 T ).

From Immunodeficiency to Humanization: The Contribution of Mouse Models to Explore HTLV-1 Leukemogenesis.

The first discovered human retrovirus, Human T-Lymphotropic Virus type 1 (HTLV-1), is responsible for an aggressive form of T cell leukemia/lymphoma. Mouse models recapitulating the leukemogenesis process have been helpful for understanding the mechanisms underlying the pathogenesis of this retroviral-induced disease. This review will focus on the recent advances in the generation of immunodeficient and human hemato-lymphoid system mice with a particular emphasis on the development of mouse models for HTLV-1-mediated pathogenesis, their present limitations and the challenges yet to be addressed.

A multicenter validation of recombinant β3 integrin-coupled beads to detect human platelet antigen-1 alloantibodies in 498 cases of fetomaternal alloimmune thrombocytopenia.

Background: Fetomaternal alloimmune thrombocytopenia (FMAIT) is caused by human platelet (PLT) antigen (HPA) incompatibility. Beads coupled with recombinant β3 integrins, displaying the biallelic HPA-1 epitopes (rHPA-1), have been shown to detect HPA-1a alloantibodies implicated in FMAIT. This report describes a multicenter validation of the beads using the results of well-characterized samples to define the optimum parameters for analysis of a large cohort of 498 clinical samples.

Flexible automated platform for blood group genotyping on DNA microarrays.

The poor suitability of standard hemagglutination-based assay techniques for large-scale automated screening of red blood cell antigens severely limits the ability of blood banks to supply extensively phenotype-matched blood. With better understanding of the molecular basis of blood antigens, it is now possible to predict blood group phenotype by identifying single-nucleotide polymorphisms in genomic DNA. Development of DNA-typing assays for antigen screening in blood donation qualification laboratories promises to enable blood banks to provide optimally matched donations.

Isolation of human CD4/CD8 double-positive, graft-versus-host disease-protective, minor histocompatibility antigen-specific regulatory T cells and of a novel HLA-DR7-restricted HY-specific CD4 clone.

Minor histocompatibility (H) Ags are classically described as self-peptides derived from intracellular proteins that are expressed at the cell surface by MHC class I and class II molecules and that induce T cell alloresponses. We have isolated three different T cell populations from a skin biopsy of a patient suffering from acute graft-versus-host disease following sex-mismatched HLA-identical bone marrow transplantation. The first population was: 1) CD4(+)/CD8(+) double-positive; 2) specific for an HLA class I-restricted autosomal Ag; 3) expressed a Tr1 profile with high levels of IL-10, but low IL-2 and IFN-γ; and 4) exerted regulatory function in the presence of recipient APCs.

[Mice are not Men and yet… how humanized mice inform us about human infectious diseases].

The study of human pathologies is often limited by the absence of animal models which are robust, cost-effective and reproduce the hallmarks of human infections. While mice have been frequently employed to study human diseases, many of important pathogens display unique human tropism. These last two decades the graft of human progenitor cells or tissues into -immunodeficient mice has allowed the elaboration of so called humanized mice.

A novel assay for the detection of anti-human platelet antigen antibodies (HPA-1a) based on peptide aptamer technology.

Background: Neonatal alloimmune thrombocytopenia is mostly due to the presence of maternal antibodies against the fetal platelet antigen HPA-1a on the platelet integrin GPIIb-IIIa. Accurate detection of anti-HPA-1a antibodies in the mother is, therefore, critical. Current diagnostic assays rely on the availability of pools of human platelets that vary according to donors and blood centers.

Does high-resolution donor typing of HLA-C or other loci upon registration confer advantages to patients?

Our study compared all requests for confirmatory typing (CT requests) received in our center between May 2007 and December 2009 (n = 134) for donors issued from 3 groups defined by different human leukocyte antigen (HLA) loci typed at different levels of resolution. We observed a significant advantage for volunteers when HLA-C 2-digit typing was available or with HLA-A, -B, -C, -DRB1 4-digit typing compared with generic HLA-A, -B, -DRB1, -DQB1 DNA typing: increased percentage of CT requests (p < 0.001), increased rate of donor selection for donation (p < 0.

l-asparaginase loaded red blood cells in refractory or relapsing acute lymphoblastic leukaemia in children and adults: results of the GRASPALL 2005-01 randomized trial.

l-asparaginase encapsulated within erythrocytes (GRASPA(®) ) should allow serum asparagine depletion over a longer period than the native form of the enzyme, using lower doses and allowing better tolerance. The GRASPALL 2005-01 study, a multicentre randomized controlled trial, investigated three doses of GRASPA(®) for the duration of asparagine depletion in a phase I/II study in adults and children with acute lymphoblastic leukaemia (ALL) in first relapse. Between February 2006 and April 2008, 18 patients received GRASPA(®) (50 iu/kg: n = 6,100 iu/kg: n = 6, 150 iu/kg: n = 6) after randomization, and six patients were assigned to the Escherichia coli native l-asparaginase (E.

Leucine-rich protein 130 contributes to apoptosis resistance of human hepatocarcinoma cells.

LRP130 is a ubiquitous protein involved in cellular homeostasis, microtubule alteration, and transactivation of a few multidrug resistance genes. Its role in resistance to apoptosis in HepG2 and HUH7 hepatocarcinoma cells was investigated. Using shRNA-producing lentiviruses to down-regulate the LRP130 gene, we showed that i) LRP130 did not affect the capacity of hepatocarcinoma cells to extrude drugs since LRP130 down-regulation was insufficient to significantly reduce P-glycoprotein production in these cells, and ii) the expression of 11 apoptosis-related genes measured by PCR-array was significantly reduced.

Multipurpose high-throughput filtering microarrays (HiFi) for DNA and protein assays.

We are reporting here a low cost colorimetric device for high-throughput multiplexed blood group genotyping and allergy diagnosis, displayed as an automated 96-well microtiter plate format. A porous polymeric membrane sealed at the bottom of each well accounts for the sensor support. For each sensing unit, a 6×6 matrix of specific probes is spotted on the external surface of the membrane resulting in 5 mm(2) microarrays.

Robust, high-throughput solution for blood group genotyping.

With the concomitant increase of blood transfusions and safety rules, there is a growing need to integrate high-throughput and multiparametric assays within blood qualification centers. Using a robust and automated solution, we describe a new method for extended blood group genotyping (HiFi-Blood 96) bringing together the throughput possibilities of complete automation and the microarray multiplexed analysis potential. Our approach provides a useful resource for upgrading blood qualification center facilities.

Inositol hexaphosphate-loaded red blood cells prevent in vitro sickling.

Background: Hypoxia is a major cause of painful vaso-occlusive crisis in sickle cell disease (SCD). Simple transfusion and red blood cell (RBC) exchange are commonly used as preventive therapies whose aim is to dilute hemoglobin (Hb)S-containing RBCs (SS-RBCs) with normal RBCs (AA-RBCs) to prevent sickling. We hypothesized that the effectiveness of transfusion could be improved by the encapsulation of inositol hexaphosphate (IHP), an allosteric Hb effector, in transfused AA-RBCs.

Development of miniaturized immunoassay: influence of surface chemistry and comparison with enzyme-linked immunosorbent assay and Western blot.

Protein microarray technology provides a useful approach for the simultaneous serodetection of various antibodies in low sample volumes. To implement functional protein microarrays, appropriate surface chemistry must be designed so that both the protein structure and the biological activity can be retained. In the current study, two surface chemistries for protein microarrays and immunofluorescent assays were developed.

Characterization of the behavior of functional viral genomes during the early steps of human immunodeficiency virus type 1 infection.

Infectious viral DNA constitutes only a small fraction of the total viral DNA produced during retroviral infection, and as such its exact behavior is largely unknown. In the present study, we characterized in detail functional viral DNA produced during the early steps of human immunodeficiency virus type 1 infection by analyzing systematically their kinetics of synthesis and integration in different target cells. In addition, we have compared the functional stability of viral nucleoprotein complexes arrested at their pre-reverse transcription state, and we have attempted to measure the kinetics of loss of capsid proteins from viral complexes through the susceptibility of the early phases of infection to cyclosporine, a known inhibitor of the interaction between viral capsid and cyclophilin A.

Characterization of simian immunodeficiency virus SIVSM/human immunodeficiency virus type 2 Vpx function in human myeloid cells.

Human immunodeficiency virus type 2 (HIV-2)/simian immunodeficiency virus SIV(SM) Vpx is incorporated into virion particles and is thus present during the early steps of infection, when it has been reported to influence the nuclear import of viral DNA. We recently reported that Vpx promoted the accumulation of full-length viral DNA following the infection of human monocyte-derived dendritic cells (DCs). This positive effect was exerted following the infection of DCs with cognate viruses and with retroviruses as divergent as HIV-1, feline immunodeficiency virus, and even murine leukemia virus, leading us to suggest that Vpx counteracted an antiviral restriction present in DCs.

Induction of high expression of CCR7 and high production of IL-12 in human monocyte-derived dendritic cells by a new bacterial component: LCOS 1013.

Dendritic cells (DCs) are the most potent antigen presenting cells of the immune system as they can act as initiators, stimulators and regulators of the immune response. Human DCs are most commonly generated for clinical use by in vitro differentiation of monocytes with exogenous cytokines. Here, we investigate the effect of LCOS 1013 on the production of mature Mo-DCs.

Characterization of the early steps of infection of primary blood monocytes by human immunodeficiency virus type 1.

Blood-circulating monocytes migrate in tissues in response to danger stimuli and differentiate there into two major actors of the immune system: macrophages and dendritic cells. Given their migratory behavior and their pivotal role in the orchestration of immune responses, it is not surprising that cells of the monocyte lineage are the target of several viruses, including human immunodeficiency virus type 1 (HIV-1). HIV-1 replicates in monocytoid cells to an extent that is influenced by their differentiation status and modulated by exogenous stimulations.

Acid deprotection of covalently immobilized peptide probes on glass slides for peptide microarrays.

Protein microarray technology has shown great advancements in the field of biomedical research and diagnosis, it allows to study and understand protein activities and protein - ligand interactions (e.g. detection of antigen-autoantibody interaction in autoimmune diseases.

Identification and quantification of fetal red blood cells in maternal blood by a dual-color flow cytometric method: evaluation of the Fetal Cell Count kit.

Background: As an alternative to the cumbersome Kleihauer-Betke test (KBT), flow cytometry represents a powerful method for the identification and quantification of fetal red blood cells (RBCs) in maternal circulation.

Study Design And Methods: The aim of this study was to evaluate the Fetal Cell Count kit (IQ Products), an innovative flow cytometric method, based on the combination of antibodies directed, respectively, against fetal hemoglobin (HbF) and carbonic anhydrase (CA), a marker expressed after birth, to discriminate fetal RBCs from adult F cells containing HbF. The investigation was performed by two French laboratories that compared the data obtained by flow cytometry and KBT in 455 pregnant or just-delivered women as well as in 124 artificial mixtures containing from 0.

Analysis of genetic variants of the poly(ADP-ribose) polymerase-1 gene in breast cancer in French patients.

Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that catalyzes the poly(ADP-ribosyl)ation of target proteins in response to DNA damage and has been proposed to play a role in DNA repair, recombination, transcription, cell death, cell proliferation, as well as in stabilization of the genome. We have recently shown that PARP-1 deficiency causes mammary tumorigenesis in mice. In the present study, we investigated whether genetic variants and single nucleotide polymorphisms (SNPs) of PARP-1 contribute to human breast cancer.

Toll-like receptor 3 (TLR3): a new marker of canine monocytes-derived dendritic cells (cMo-DC).

Toll-like receptors (TLRs) are a family of functionally important receptors for recognition of pathogen-associated molecular pattern (PAMP) since they trigger the pro-inflammatory response and upregulation of costimulatory molecules, linking the rapid innate response to adaptative immunity. In human leukocytes, TLR3 has been found to be specifically expressed in dendritic cells (DC). This study examined the expression of TLR3 in canine monocytes-derived DC (cMo-DC) and PBMC using three new anti-TLR3 mAbs (619F7, 722E2 and 713E4 clones).