Publications by authors named "Sandrine Lafarge"

Chronic lymphocytic leukemia is a malignancy driven by abberant B cell signaling and survival. Leukemic B cells accumulate in the peripheral blood and the lymphoid organs where contact with stromal cells and T cells provide critical survival signals. Clinical severity of CLL is associated with several prognostic markers including expression of the kinase ZAP-70.

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CLL cell survival and proliferation is enhanced through direct contact with supporting cells present in lymphoid tissues. PI3Ks are critical signal transduction enzymes controlling B cell survival and activation. PI3K inhibitors have entered clinical trials and show promising therapeutic activity; however, it is unclear whether PI3K inhibitor drugs differentially affect ZAP-70 positive versus negative CLL cells or target specific microenvironmental interactions.

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Clonal diversity in multiple myeloma (MM) includes both MM-related and MM-unrelated clonal expansions which are subject to dominance exerted by the MM clone. Here we show evidence for the existence of minor but highly expanded unrelated B-cell clones in patients with MM defined by their complementary determining region 3 (CDR3) peak. We further characterize these clones over the disease and subsequent treatment.

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The phosphoinositide 3-kinase (PI3K) pathway is a central signal transduction axis controlling normal B cell homeostasis and activation in humoral immunity. The p110δ PI3K catalytic subunit has emerged as a critical mediator of multiple B cell functions. The activity of this pathway is regulated at multiple levels, with inositol phosphatases PTEN and SHIP both playing critical roles.

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In population studies, the relative survival in chronic lymphocytic leukemia (CLL) decreases with age. In this study, we demonstrated in a cohort of 189 patients from a CLL clinic that overall survival was lower in the sub-cohort of patients aged ≥ 70 years, but causes of death were similar for all age groups, being progressive CLL, secondary malignancies and infections. As normal individuals age, the plasma levels of inflammatory cytokines, such as interleukin-6 (IL-6) and IL-8, can increase.

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Background: Recent studies have demonstrated that infused platelets (PLTs) can promote inflammation. The objective of this study was to evaluate the impact of storage of transfusion-grade PLTs on the peripheral blood mononuclear cells (PBMNCs) of the recipient.

Study Design And Methods: An in vitro cell model system was established to measure the degree of activation of donor PLTs during 5 days of their storage and then to measure immune cell activation by detecting marker expression in coculture experiments.

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B-cell expression of certain Toll-like receptors (TLRs) is important in linking innate and adaptive immune responses in normal and pathological conditions. The expression of TLR9 plays a role in the recognition of conserved pathogen motifs in a manner that is dependent on B-cell localization, deduced from B-cell phenotype. The nature of TLR9 function is unclear.

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Blood platelets link the processes of haemostasis and inflammation. This study examined the immunomodulatory factors released by platelets after Toll-Like Receptor 4 (TLR4) engagement on their surfaces. Monoclonal anti-human FcgammaRII Ab (IV.

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Background: Cytokines have essential roles on intercellular communications and are effective in using a variety of intracellular pathways. Among this multitude of signalling pathways, the NF-kappaB (nuclear factor kappaB) and STAT (signal transducer and activator of transcription) families are among the most frequently investigated because of their importance. Indeed, they have important role in innate and adaptive immunity.

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Objective: Blood platelets represent a link between hemostasis, inflammation, and tissue repair. Their role in immune responses and inflammation mainly involves many molecules, among which Toll-like receptor, major histocompatibility complex class I, CD40 and CD154/CD40 ligand (CD40L). As platelets are the major purveyor of soluble CD40L (sCD40L), we sought to determine their involvement in CD40/CD40L-dependent immune responses and to understand the interactions between platelets and peripheral B lymphocytes.

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