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The role of human dendritic cells in meningococcal and listerial meningitis.

Few bacteria are capable of causing infections of the central nervous system (CNS), one of the most subtly shielded anatomical structures within the human body. Neisseria meningitidis is an important cause of bacterial meningitis and commonly affects otherwise healthy infants and adolescents. In contrast, Listeria monocytogenes is a cause of septicaemia and meningitis in neonates and immunocompromised adults. Dendritic cells (DCs) provide the physical link between the innate and adaptive immune system and play a crucial role in host defence against invading bacterial pathogens. The mechanisms

Mediastinal mixed dendritic cell sarcoma with hybrid features.

This report describes a recurrent sarcoma involving the soft tissues of the posterior mediastinum with features of both follicular dendritic and interdigitating dendritic cells. Histologically, the tumour, which was a recurrent neoplasm 19 years after the initial removal, was composed of bland spindle shaped cells with interspersed inflammatory cells, predominantly lymphocytes. Immunohistochemically, the spindle cells were positive for S100 protein, CD45, CD68, and vimentin, but negative for CD21 and CD35 (markers of follicular dendritic cells). The immunophenotype was in keeping with interdig

Дендритическая патология позвоночника: причина или следствие неврологических расстройств?

Измененные дендритические позвоночники характерны для травмированного или больного мозга. Можно выделить две общие категории патологии позвоночника: патологии распределения и патологии ультраструктуры. Патологии распределения позвоночника влияют на многие позвоночники вдоль дендритов нейрона и включают изменяющиеся числа позвоночника, искаженные формы позвоночника и аномальные локси происхождения позвоночника на нейроне. Патологии ультраструктуры позвоночника связаны с деформацией подклеточных органелл внутри дендритических позвоночников. Распределение шпильки изменяется на зрелых нейронах пос

Совпадение в аннотации оригинала
Altered dendritic spines are characteristic of traumatized or diseased brain. Two general categories of spine pathology can be distinguished: pathologies of distribution and pathologies of ultrastructure. Pathologies of spine distribution affect many spines along the dendrites of a neuron and include altered spine numbers, distorted spine shapes, and abnorma…

Isolation of dendritic cells from mouse lymph nodes.

Lymph nodes are the primary sites of T-cell stimulation by dendritic cells (DC). After contact with antigens, DCs migrate to draining lymph nodes from the skin and other tissues (1-3). Investigation of the morphology and function of lymph node DCs may provide important information about the role of these cells in normal and pathological conditions. Therefore, lymph nodes are popular sites for the isolation of dendritic cells. Dendritic cells isolated from lymph nodes represent interdigitating" DCs that are localized in T-dependent regions of lymph nodes. DCs represent about 1% of the total pop

Dendritic cell development from common myeloid progenitors.

Dendritic cells (DCs) are professional antigen-presenting cells which both initiate adaptive immune responses and control tolerance to self-antigens. It has been suggested that these different effects on responder cells depend on subsets of DCs arising from either myeloid or lymphoid hematopoietic origins. In this model, CD8 alpha+ Mac-1- DCs are supposed to be of lymphoid while CD8 alpha- Mac-1+ DCs are supposed to be of myeloid origin. Here we summarize our findings that both CD8 alpha+ and CD8 alpha- DCs can arise from clonogenic common myeloid progenitors (CMPs) in both thymus and spleen.

Inhibition of dendritic cell differentiation by fumaric acid esters.

Fumaric acid esters have proved to be effective for the systemic treatment of severe psoriasis vulgaris. These compounds have been shown to induce a Th2-like cytokine secretion pattern in T cells and to reduce keratinocyte proliferation in vitro. Dendritic cells seem to be of major importance as regulatory cells driving the psoriatic tissue reaction. Monocytes or CD34-positive myeloid progenitor cells are precursors of dendritic cells that can be generated in vitro by culture with granulocyte-macrophage colony-stimulating factor and interleukin-4. Using this model the effect of fumaric acid es

Rapid plasticity of dendritic spine: hints to possible functions?

Contrary to a century-old belief that dendritic spines are stable storage sites of long term memory, the emerging picture from a recent flurry of exciting observations using novel high resolution imaging methods of living cells in culture is that of a dynamic structure, which undergoes fast morphological changes over periods of hours and even minutes. Concurrently, the nature of stimuli which cause formation or collapse of dendritic spines has changed from a mysterious Hebbian-governed plasticity producing stimulus to the more trivial activation of the synapse by strong/weak stimulation. The m

Human dendritic cells as targets of dengue virus infection.

Dengue virus infections are an emerging global threat. Severe dengue infection is manifested as dengue hemorrhagic fever and dengue shock syndrome, both of which can be fatal complications. Factors predisposing to complicated disease and pathogenesis of severe infections are discussed. Using immunohistochemistry, immunofluorescence, flow cytometry, and ELISA techniques, we studied the cellular targets of dengue virus infection, at both the clinical (in vivo) and the laboratory (in vitro) level. Resident skin dendritic cells are targets of dengue virus infection as demonstrated in a skin biopsy

Interaction of dendritic cells with mycobacteria: where the action starts.

Dendritic cells (DC) are the major antigen-presenting cells in the induction of cellular responses to intracellular pathogens, such as mycobacteria. Recent studies have shown that they also play a critical role in the regulation of immune responses. The interaction of DC with microbial antigens may be the controlling factor in the development of a Th1-orientated protective immunity. Analysis of the innate response of DC to mycobacteria and the involvement of the DC receptors in antigen recognition have highlighted the pivotal role of these cells in T-cell activation. Mycobacteria-infected DC h

Dendritic cells: expansion and differentiation with hematopoietic growth factors.

Dendritic cells are critical initiators of immune responses mediated by T and B lymphocytes. Dendritic cells process antigens captured in the periphery, then emigrate to lymphoid organs. There they complete their maturation by upregulating important accessory molecules and secreting cytokines, all of which support potent stimulation of antigen-specific lymphocytes. These lymphocytes return to the periphery to complete the immune response. Investigators have discovered culture systems that use exogenous hematopoietic cytokines to support the growth, differentiation, and maturation of dendritic

Dendritic cells/chimerism/alleviation of chronic allograft rejection.

Chronic rejection (CR) is the major obstacle of long-term successful organ transplantation. Using a recently developed rat model of CR, we found that heart allografts susceptible to development of CR showed an early (< 10 days) dramatic disappearance of donor MHC class II+ cells, including ED2+ tissue macrophages, and an influx of recipient ED1+ macrophages intermixed with small numbers of recipient ED2+ and OX62+ cells. In contrast, donor MHC class II+ cells persisted in allografts resistant to CR with a small influx of recipient macrophages. MHC class II+ cells function as potent modulators

Dendritic cells efficiently induce protective antiviral immunity.

Cytotoxic T lymphocytes (CTL) are essential for effective immunity to various viral infections. Because of the high speed of viral replication, control of viral infections imposes demanding functional and qualitative requirements on protective T-cell responses. Dendritic cells (DC) have been shown to efficiently acquire, transport, and present antigens to naive CTL in vitro and in vivo. In this study, we assessed the potential of DC, either pulsed with the lymphocytic choriomeningitis virus (LCMV)-specific peptide GP33-41 or constitutively expressing the respective epitope, to induce LCMV-spec

UV guided dendritic growth patterns and the networking of melanocytes.

Whole skin organ cultures of vitiliginous skin show that the marginal melanocytes are highly sensitive to a pulse of UV exposure (210-380 nm) during the G2 phase of the cell cycle, as seen by prominent dendricity. Melanocytes are highly dendritic in the epidermis overlying rapidly growing tumors, as well as within proliferative lesions such as basal cell carcinomas and aggressive seborrheic keratosis. In the organ cultures the dendrites extend towards the source of UV, i.e. the surface, while the main body lies along the basement membrane. The epidermal melanocytes overlying tumors lie almost …

Dendritic and histochemical development and ageing in patients with Down's syndrome.

Mental retardation and dementia characteristic of Down's syndrome (DS) have a complex pathogenesis. Golgi and immunohistochemical studies were done on DS patients and controls from foetuses and elderly adults. Golgi studies on the cerebral cortex revealed that the postsynaptic spines on the basal dendrites increase from neonate to 15 years of age and gradually decrease after 20 years in controls, but poorly increase in children and rapidly decrease in adults with DS. This deficient synaptogenesis and dendritic atrophy may be related to mental retardation. On the other hand, immunohistochemistr…

Abnormal dendritic development in maple syrup urine disease.

The neuropathology of a 6-year-old boy with maple syrup urine disease revealed spongy appearance of the white matter and marked edema of the brainstem. Golgi studies demonstrated aberrant orientation of neurons together with abnormalities of dendrites and dendritic spines. Similar changes were observed in a patient with dihydropteridine reductase deficiency. Disorders of amino acid metabolism may be associated with alterations in the terminal stages of neuronal migration and maturation.

Dendritic cells and the initiation of contact sensitivity to fluorescein isothiocyanate.

Lymph node cells taken 24 hr after skin-painting mice with the contact sensitizer fluorescein isothiocyanate (FITC) induce delayed-type hypersensitivity in recipient mice. Skin-painting increased the number of dendritic cells (DC) in the draining lymph nodes without significantly changing the number of lymphocytes at 24 hr. The antigen was preferentially located on the DC. Raising the dose of FITC increased both the number of DC and the amount per cell. The addition of these DC to syngeneic lymph node cells at a ratio as low as 1:300 initiated proliferative responses in vitro. The level of pro

Ultrastructure of the olfactory neuron of the bullfrog: the dendrite and its microtubules.

The ciliated dendritic bulb of the olfactory neuron of the bullfrog was studied with the electron microscope, with emphasis on microtubular elements. Methods used included various fixation procedures with and without detergent extraction, serial sectioning, microtubule polarity assays, and an assay to demonstrate F-actin. Structural continuity exists, via microtubules, between the ciliary membrane and the perikaryon of the neuron. One type of structural link connects the distal end of the basal body to the plasma membrane and, in slightly oblique cross sections of the basal body, the link show

Axons and axon terminals of cerebellar Purkinje cells and basket cells have higher levels of parvalbumin immunoreactivity than somata and dendrites: quantitative analysis by immunogold labeling.

The immunointensities of calcium-binding proteins parvalbumin (PV) and calbindin D28K were quantified in different parts of Purkinje cells a … les were used for statistical comparison of the relative levels of PV and calbindin D28K in somata, dendrites, dendritic spines, axons and axon terminals of Purkinje cells, and interneurons. The axons and axon terminals of Purkinje cells and basket cells had significantly higher levels of PV immunoreactivity than Purkinje cell somata, primary, secondary, an …

Dendritic-cell-specific ICAM3-grabbing non-integrin is essential for the productive infection of human dendritic cells by mosquito-cell-derived dengue viruses.

Dengue virus (DV) is a mosquito-borne flavivirus that causes haemorrhagic fever in humans. DV primarily targets immature dendritic cells (DCs) after a bite by an infected mosquito vector. Here, we analysed the interactions between DV and human-monocyte-derived DCs at the level of virus entry. We show that the DC-specific ICAM3-grabbing non-integrin (DC-SIGN) molecule, a cell-surface, mannose-specific, C-type lectin, binds mosquito-cell-derived DVs and allows viral replication. Conclusive evidence for the involvement of DC-SIGN in DV infection was obtained by the inhibition of viral infection b

Signaling from epithelial to dendritic cells of the thyroid gland: evidence for thyrocyte-derived factors controlling the survival, multiplication, and endocytic activity of dendritic cells.

Intrathyroidal dendritic cells (DC) isolated at the same time and then cultured with thyrocytes in the presence of thyrotropin (TSH) keep a phenotype of immature DC (Croizet et al, 2000). As DC from other sources are known to undergo a rapid maturation in vitro, we hypothesized that the maintenance of thyroid-derived DC in an immature state might be caused by thyrocytes-DC interactions. In this study, we investigated whether thyroid-derived DC could change their phenotype in response to TSH stimulation of thyrocytes. Over an 8-day period of culture, the population of DC increased 2- to 3-fold