Publications by authors named "Alon R"

Although the CXCL12/CXCR4 pathway has been prior investigated for its prometastatic and immuno- suppressive roles in the tumor microenvironment, evidence on the spatiotemporal regulation of these hallmarks has been lacking. Here, we demonstrate that CXCL12 forms a gradient specifically around cancer cell intravasation doorways, also known as Tumor Microenvironment of Metastasis (TMEM) doorways, thus facilitating the chemotactic translocation of prometastatic tumor cells expressing CXCR4 toward the perivascular TMEM doorways for subsequent entry into peripheral circulation. Fur- thermore, we demonstrate that the CXCL12-rich micro-environment around TMEM doorways may cre- ate immunosuppressive niches, whereby CD8 T cells, despite being attracted to these regions, often exhibit reduced effector functions, limiting their efficacy.

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Myocardial injury may ultimately lead to adverse ventricular remodeling and development of heart failure (HF), which is a major cause of morbidity and mortality worldwide. Given the slow pace and substantial costs of developing new therapeutics, drug repurposing is an attractive alternative. Studies of many organs, including the heart, highlight the importance of the immune system in modulating injury and repair outcomes.

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Background: Typically-developing siblings of individuals with Down Syndrome often experience complex emotions towards their sibling. This study explored how social support, personal resources (optimism, sense of coherence [SOC]), and individual variables (sex, religious affiliation, siblings' functionality) may impact emerging adult siblings' emotions toward their sibling with Down Syndrome.

Methods: Participants were 292 siblings of individuals with DS ranging in age from 18-27 (M=21.

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Classical monocytes (CMs) are ephemeral myeloid immune cells that circulate in the blood. Emerging evidence suggests that CMs can have distinct ontogeny and originate from either granulocyte-monocyte- or monocyte-dendritic-cell progenitors (GMPs or MDPs). Here, we report surface markers that allowed segregation of murine GMP- and MDP-derived CMs, i.

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Lymphocyte priming in lymph nodes (LNs) was postulated to depend on the formation of stable T cell receptor (TCR)-specific immune synapses (ISs) with antigen (Ag)-presenting dendritic cells (DCs). The high-affinity LFA-1 ligand ICAM-1 was implicated in different ISs studied in vitro. We dissect the in vivo roles of endogenous DC ICAM-1 in Ag-stimulated T cell proliferation and differentiation and find that under type 1 polarizing conditions in vaccinated or vaccinia virus-infected skin-draining LNs, Ag-presenting DCs engage in ICAM-1-dependent stable conjugates with a subset of Ag-specific CD8 blasts.

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αLβ2 (LFA-1) mediated interactions with ICAM-1 and ICAM-2 predominate leukocyte-vascular interactions, but their functions in extravascular cell-cell communications is still debated. The roles of these two ligands in leukocyte trafficking, lymphocyte differentiation, and immunity to influenza infections were dissected in the present study. Surprisingly, double ICAM-1 and ICAM-2 knock out mice (herein ICAM-1/2 mice) infected with a lab adapted H1N1 influenza A virus fully recovered from infection, elicited potent humoral immunity, and generated normal long lasting anti-viral CD8 T cell memory.

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Breast tumors and their derived circulating cancer cells express the leukocyte β integrin ligand Intercellular adhesion molecule 1 (ICAM-1). We found that elevated ICAM-1 expression in breast cancer cells results in a favorable outcome and prolonged survival of breast cancer patients. We therefore assessed the direct contribution of ICAM-1 expressed by breast cancer cells to breast tumorigenesis and lung metastasis in syngeneic immunocompetent mice hosts using spontaneous and experimental models of the lung metastasis of the C57BL/6-derived E0771 cell line, a luminal B breast cancer subtype.

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T cells defend against cancer and viral infections by rapidly scanning the surface of target cells seeking specific peptide antigens. This key process in adaptive immunity is sparked upon T cell receptor (TCR) binding of antigens within cell-cell junctions stabilized by integrin (LFA-1)/intercellular adhesion molecule-1 (ICAM-1) complexes. A long-standing question in this area is whether the forces transmitted through the LFA-1/ICAM-1 complex tune T cell signaling.

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School counselors' occupational plans were investigated in terms of the mediating role of occupational self-efficacy including three antecedents (role clarity, role autonomy, social support) on three outcomes (life satisfaction, job satisfaction, occupational plans) among 483 female Israeli school counselors, aged 26-69. High levels of the three antecedents were associated with high levels of occupational self-efficacy, which in turn was associated with high levels of life and job satisfaction and with counselors' plans to remain in their profession. The antecedents also demonstrated direct effects with job satisfaction.

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Dendritic cells (DC), the classic antigen-presenting cells of the immune system, switch from an adhesive, phagocytic phenotype in tissues, to a mature, nonadhesive phenotype that enables migration to lymph nodes to activate T cells and initiate antitumor responses. Monocyte-derived DCs are used in cancer immunotherapy, but their clinical efficacy is limited. Here, we show that cultured bone marrow-derived DCs (BM-DC) expressing dysfunctional β2-integrin adhesion receptors displayed enhanced tumor rejection capabilities in B16.

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Leukocyte microvilli are elastic actin-rich projections implicated in rapid sensing and penetration across glycocalyx barriers. Microvilli are critical for the capture and arrest of flowing lymphocytes by high endothelial venules, the main lymph node portal vessels. T lymphocyte arrest involves subsecond activation of the integrin LFA-1 by the G-protein-coupled receptor CCR7 and its endothelial-displayed ligands, the chemokines CCL21 and CCL19.

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The integrin LFA-1 is crucial for T cell entry into mammalian lymph nodes and tissues, and for promoting interactions with antigen-presenting cells (APCs). However, it is increasingly evident that LFA-1 has additional key roles beyond the mere support of adhesion between T cells, the endothelium, and/or APCs. These include roles in homotypic T cell-T cell (T-T) communication, the induction of intracellular complement activity underlying Th1 effector cell polarization, and the support of long-lasting T cell memory.

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Microtubules (MTs) control cell shape and intracellular cargo transport. The role of MT turnover in the migration of slow-moving cells through endothelial barriers remains unclear. To irreversibly interfere with MT disassembly, we have used the MT-stabilizing agent zampanolide (ZMP) in Β16F10 melanoma as amodel of slow-moving cells.

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The three-dimensional organization of chromatin contributes to transcriptional control, but information about native chromatin distribution is limited. Imaging chromatin in live larvae, with preserved nuclear volume, revealed that active and repressed chromatin separates from the nuclear interior and forms a peripheral layer underneath the nuclear lamina. This is in contrast to the current view that chromatin distributes throughout the nucleus.

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The mechanisms by which the nuclear lamina of tumor cells influences tumor growth and migration are highly disputed. Lamin A and its variant lamin C are key lamina proteins that control nucleus stiffness and chromatin conformation. Downregulation of lamin A/C in two prototypic metastatic lines, B16F10 melanoma and E0771 breast carcinoma, facilitated cell squeezing through rigid pores, and reduced heterochromatin content.

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Neutrophils are the most prevalent leukocytes in the human body. They have a pivotal role in the innate immune response against invading bacterial and fungal pathogens, while recent emerging evidence also demonstrates their role in cancer progression and anti-tumor responses. The efficient execution of many neutrophil effector responses requires the presence of 2 integrins, in particular CD11a/CD18 or CD11b/CD18 heterodimers.

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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19). Understanding of the fundamental processes underlying the versatile clinical manifestations of COVID-19 is incomplete without comprehension of how different immune cells are recruited to various compartments of virus-infected lungs, and how this recruitment differs among individuals with different levels of disease severity. As in other respiratory infections, leukocyte recruitment to the respiratory system in people with COVID-19 is orchestrated by specific leukocyte trafficking molecules, and when uncontrolled and excessive it results in various pathological complications, both in the lungs and in other organs.

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Foxp3+ regulatory T cells (Tregs) are potent suppressor cells, essential for the maintenance of immune homeostasis. Most Tregs develop in the thymus and are then released into the immune periphery. However, some Tregs populate the thymus and constitute a major subset of yet poorly understood cells.

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Neutrophils provide first line of host defense against bacterial infections utilizing glycolysis for their effector functions. How glycolysis and its major byproduct lactate are triggered in bone marrow (BM) neutrophils and their contribution to neutrophil mobilization in acute inflammation is not clear. Here we report that bacterial lipopolysaccharides (LPS) or Salmonella Typhimurium triggers lactate release by increasing glycolysis, NADPH-oxidase-mediated reactive oxygen species and HIF-1α levels in BM neutrophils.

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Objective: To evaluate the prevalence and varying severity of obstructive sleep apnea (OSA) amongst those newly diagnosed with retinal vein occlusion (RVO), and screen patients with the use of 2 in-office-administered questionnaires validated against polysomnography.

Design: Prospective cross-sectional study.

Participants: Consecutive adult patients (≥18 years of age) with a new diagnosis of RVO confirmed with intravenous fluorescein angiography were enrolled.

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T cell surfaces are covered with microvilli, actin-rich and flexible protrusions. We use super-resolution microscopy to show that ≥90% of T cell receptor (TCR) complex molecules TCRαβ and TCRζ, as well as the co-receptor CD4 (cluster of differentiation 4) and the co-stimulatory molecule CD2, reside on microvilli of resting human T cells. Furthermore, TCR proximal signaling molecules involved in the initial stages of the immune response, including the protein tyrosine kinase Lck (lymphocyte-specific protein tyrosine kinase) and the key adaptor LAT (linker for activation of T cells), are also enriched on microvilli.

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It is unclear if naïve T cells require dendritic cell ICAMs to proliferate inside lymph nodes. To check if and when CD4 lymphocytes use ICAMs on migratory DCs, wild-type and ICAM-1 and 2 double knock out bone marrow-derived DCs pulsed with saturating levels of an OT-II transgene-specific ovalbumin-derived peptide were co-transferred into skin-draining lymph nodes. Intravital imaging of OT-II lymphocytes entering these lymph nodes revealed that ICAM-1 and -2 deficient migratory DCs formed fewer stable conjugates with OT-II lymphocytes but promoted normal T cell proliferation.

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Objective: Despite the high prevalence of dyspareunia, published data focused on childbirth is scarce. This study aimed to evaluate the prevalence of dyspareunia in a random primiparae parturient population, characterize their features, and describe associated perinatal outcomes.

Study Design: In this prospective observational study we approached primiparous women admitted to our labor ward.

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Background: Raising a child with special needs challenges mothers in complicated ways, yet, alongside these difficulties, there is evidence for maternal post-crisis growth. Social support is one element that may contribute to growth.

Aims: This study explores the relationship between social support and post-crisis growth, examines type of disability as a mediating variable between support and growth, and, looks at the relations between subtypes of support and growth.

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