Publications by authors named "Yechiel Becker"

The history of mankind over many millennia has been marred by many epidemics caused by viruses which infect the human respiratory system and alimentary tract. The current HIV-1/AIDS pandemic, however, is caused by one virus mutant, HIV-1M, which has evolved to infect humans through the genitals. The virus is able to use the innate system cells of the infected individual to inactivate the adaptive immune system, causing AIDS.

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Enfuvirtide (ENF, T-20, Fuzeon) is the first synthetic peptide to be modeled according to the amino acid sequence of HIV-1 heptad repeat 2, which was used to treat cohorts of HIV-1-infected individuals who had failed to respond to treatment with the anti-HIV-1 cocktail HAART. It was reported that when injected subcutaneously, Enfuvirtide reduced viral RNA in patients' blood by 1.96 log(10), leading to a subsequent increase in the number of CD4(+) T cells in the blood.

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The reviews on HIV-1/AIDS [1-8] highlighted the mechanism by which HIV-1 virions utilize dendritic cells (DCs) for transport from the genitals, the portal of virus infection, to the draining lymph nodes where DCs carry HIV-1 virions and present viral antigens by HLA class I and II to CD4(+) T cells. Interaction of the T cells with viral antigens presented by HLA class II molecules polarizes them to become Th2 cells, the targets of HIV-1 infection and producers of HIV-1 progeny virions. The T cells which interact with viral antigen presented by HLA class I polarize to become Th1 cells, which stimulate the CD8(+) T cell precursors to develop into antiviral cytotoxic T cells.

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Based on the hypothesis that respiratory syncytial virus (RSV) sG protein causes allergy in patients, it is suggested that treatment of RSV patients with antagonists of IL-4 and FKN early in infection will prevent the increased level of IL-4 in the serum. Together with CpG ODNs that induce Toll-like receptor 9(+) (TLR9(+)) plasmacytoid dendritic cells to release type I IFN-alpha and -beta will reactivate the inhibited Th1 cells and the antiviral cytotoxic T leukocytes. In addition, binding of CpG ODNs to TLR9(+) B cells will stop IgE synthesis and antiviral IgG and IgA will continue.

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Infection of infants in their first year of life, children and elderly people with the respiratory syncytial virus (RSV) endangers the life of the patient. An attempt to develop a formalin-inactivated RSV (FI-RSV) vaccine during the 1960s resulted in an aggravated infection in immunized children, leading to hospitalization, while infection of non-immunized children produced much milder symptoms. The reason for this remained an enigma, one which was gradually solved over the last decade by many researchers who studied the molecular biology of RSV infection of respiratory ciliary cells.

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The immune system of the human organism comprises the innate system cells and the adaptive immune cells. The former include the hematopoietic cells, mast cells, basophils, monocytes, dendritic cells (DCs) and macrophages, and the latter include CD4+ T cells, CD8+ T cells, T regulatory cells (Tr) and B cells. The innate system DCs are the major antigen-presenting cells to Th(o) CD4+ T cells in lymph nodes that polarize into T helper 1 (Th1) and T helper 2 (Th2) cells, which subsequently produce different cytokines.

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Resistance to HIV-1 infection in Europeans is associated with a mutation in the gene that codes for the CCR5 protein that is present in Th2 cells and serves as a coreceptor for HIV-1 R5 strain. A deletion of 32 amino acids from the cytokine receptor prevents infection. This mutation prevails in Europeans and is absent in Africans.

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The Joint United Nations Program on HIV-1/AIDS (UNAIDS) announced its goal to stop HIV-1 transmission by antiviral (HAART) treatment of patients since at the end of 2003 the number of people living with HIV-1 was 38 million, 25 million in the sub-Saharan region of Africa. The present review deals with a new approach to simultaneously treat HIV-1/AIDS patients in HIV-1 endemic regions with CpG oligodeoxynucleotides (ODNs) and people at high risk of infection with a vaccine containing CpG ODNs combined with synthetic HIV-1 peptides by intranasal and intradermal applications. During HIV-1 infection a gradual increase in the levels of IL-4 and IgE in the patients' serum, was reported.

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Reevaluation of the increase in the levels of IgE and IL-4 in sera of HIV-1 infected and AIDS patients led to the suggestion that AIDS resembles allergy. Studies on the properties of the viral shed gp120 revealed that it resemble environmental allergens in their ability to induce hematopoietic cells to release large amounts of Th2 cytokines, inhibitors of the patients adaptive immune response. Yet, induction of TLR9+ plasmacytoid DCs by CpG ODNs cause the release of type I interferons, inhibitors of HIV-1 replication and IL-4 release from hematopoietic cells.

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Background And Objectives: Low level laser irradiation (LLLI) is used to promote wound healing. Molecularly it is known to stimulate mitochondrial membrane potential (MMP), cytokine secretion, and cell proliferation. This study was designed to determine the influence of LLLI on the kinetics of MMP stimulation and decay, specific cytokine gene expression, and subcellular localization of promyelocytic leukemia (PML) protein on HaCaT human keratinocytes.

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The possibility that the induction of T helper 2 (Th2) cytokine synthesis and the gradual increase in interleukin 4 (IL-4) and IgE levels during HIV-1 infection are an allergic response to HIV-1 proteins was raised in the author's previous article [Becker, Virus Genes 28, 1-4, 2004]. The present review extends this hypothesis by citing experimental reports which indicate that HIV-1 shed gp120 virions share a striking resemblance with the allergens that bind to IgE molecules bound to Fc epsilon receptor I-positive (Fc epsilon RI) cells (mast cells, basophils, monocytes, and dendritic cells, DC) and then induce them to release and synthesize the IL-4 cytokine. In the earlier review, it was established that the IL-4 cytokine is responsible for the following processes: IgE synthesis by B cells and the inhibition of antiviral IgG synthesis; the inactivation of T helper 1 (Th1) cells; and the inhibition of the antiviral cytotoxic T cell (CTL) response.

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We examined whether immunization with the nonpathogenic strain R-15 of herpes simplex virus-1 (HSV-1) may prevent the clinical and neuroendocrine changes induced by the pathogenic HSV-1 strain Syn17+. Inoculation of strain Syn17+ to control rats induced fever, marked motor hyperactivity and aggressive behavior, and increased serum ACTH, corticosterone (CS) and brain prostaglandin-E2 production. Mortality was 100%.

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HIV-1 is equipped with the envelope gp160 glycoprotein for interaction with Langerhans cells (LCs) and dendritic cells (DCs), the members of the innate immune system, which confront the virus at the portal of virus entry in the human body. These cells are equipped with receptors by which they bind and endocytose the virus. The gp120 glycoprotein is used for binding to CD4 receptor and CCR5 co-receptor of T helper 2 (Th2) cells and the virions shed gp120 is able to induce FcepsilonRI+ hematopoietic cells to produce IL-4, which inactivate the host adaptive immune response.

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The HIV-1 infection in humans induces an early cellular immune response to react to the viral proteins with a cytotoxic T cell (CTL) response that fails to inhibit virus replication and the spread of the virus. It became evident that the progression of the disease causes chronic changes to the immune system of which a gradual increase in IgE antibodies is one of its features. When the HIV-1 epidemic began, the relation between the gradual increase in IgE content and AIDS was not understood, but later it became a marker for disease prognosis.

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Atopic dermatitis (AD) serves as a contraindication for the immunization of AD patients with a live vaccinia virus (VV) vaccine. The antiallergen IgE interacts with the Fc receptors (FcepsilonRI) on dendritic cell (DC) membranes and with allergen molecules. The immunological events that lead to AD disease, the activation of the T-helper 2 (Th2) immune response, the synthesis of the cytokines IL-4, IL-5, IL-13, and the inhibition of the T-helper 1 (Th1) damage the capacity of the host to develop anti-VV cytotoxic cells (CTLs).

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Thousands of scientists participated in the World of Microbes Congress, which was organized by the International Union of the Microbiological Societies (IUMS) and took place in the Palais de Congres in Paris, France from 27 July to 1 August 2002. The attendees were members of the IUMS divisions of Bacteriology and Applied Microbiology, Mycology, and Virology. In addition to the symposia that were organized by each division, joined plenary symposia were held, which encompassed subjects of common interest to all microbiologists.

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Almost 100 years elapsed after the discovery of dendritic cells in the human skin epithelium by Paul Langerhans in 1868 until the initiation of research on those cells was reinitiated. The present paper provides the milestones in the research on Langerhans/dendritic cells (LCs/DCs) between 1960 and 1989. This historical review will explain how researchers gradually discovered the role of the bone marrow-derived dendritic cells in the immune response.

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In 1868, dendritic cells (DCs) were discovered in human skin by Paul Langerhans using gold staining. These cells were named Langerhans cells (LCs) after their discoverer who, due to their dendrites, regarded them as neurons. One hundred and eleven years were to pass until it was discovered that in vertebrates these cells originate in the bone marrow as monocytes.

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The review of recent studies using DNA microarrays shed new light on herpes simplex virus (HSV) replicative cycle, the response of immature dendritic cells (DCs) to pathogens and the response of neurons in trigeminal ganglia to virus reactivation. These studies provided a better understanding of the molecular biology of HSV during infection, latency and reactivation. The research on the sensory trigeminal neurons and the neuronal axons (type C fibers) that transverse the skin basal membrane, enter the skin epidermis and interact with the cell membrane of the skin resident immature DCs provided an insight on the connection between the nervous system and the host immune system.

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The sequencing and deciphering of the human genome provided an insight into the gene complement of the human chromosomes as well as information on the nongenic sequences that constitute the chromosomal DNA molecules. The analyses of the genes and nongenic sequences in the human genome also provided important information on the presence of endogenous retroviruses, retroposons, retrotransposition of genes in the human genome as well as retroduplication of genes and distribution of the duplicated genes in different chromosomes. These issues were discussed in the first Special Issue of Virus Genes on Molecular Evolution of Viruses-Past and Present.

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