Subject dendritic cell

Malefyt R. Meng Q. Kay AB. Phipps S. Lee TH. Ying S Early production of thymic stromal lymphopoie-tin precedes infiltration of dendritic cells expressing its receptor in allergen-induced late phase cutaneous responses in atopic subjects. Allergy 2009 64 1014-1022. 

It is generally accepted (based on clinical and in vitro studies) that mast cells (and basophils), IgE and FceRI are involved in most cases of allergen-induced anaphylaxis in humans. However, it is difficult to define the exact roles and relative importance of mast cells, basophils, and other potential effector cells (e.g monocytes/macrophages, dendritic cells) in either IgE-dependent or IgE-independent human anaphylaxis. Unlike in mice, we neither have access to mast cell- or basophil-deficient humans nor can we genetically manipulate human subjects to produce such phenotypes. 

Upham JW, Denburg JA, O Byrne PM Rapid response of circulating myeloid dendritic cells to inhaled allergen in asthmatic subjects. Clin Exp Allergy 2002 32 818-823. 

Based on the kno vledge of the processes of T cell sensitization by chemicals and the importance of T cells in induction of autoimmune diseases a number of key indicators of autoimmunogenic compounds can be defined. These include the possibility to be subject of metabolic conversion (either intra- or extra-hepatically), the capacity to activate dendritic cells, to induce cytokine production (in any cell type), or the potency to cause cell stress or cell death. Most of these processes can be studied in vitro, but none of the available methods have been tested for this purpose and often chemicals may behave completely different in vitro than in vivo. However, much can be learned from initiatives to design alternative methods for contact allergens, as many of these basic processes that lead to T cell sensitization are similar for allergenic and autoimmunogenic chemicals. 

Cytokines have been under clinical investigation as adjuvants to vaccines, and IFNs and IL-2 have shown some positive effects in the response of human subjects to hepatitis vaccine. IL-12 and GM-CSF have also shown adjuvant effects with vaccines. GM-CSF is of particular interest because it promotes recruitment of professional antigen-presenting cells such as the dendritic cells required for priming naive antigen-specific T-lymphocyte responses. There are some claims that GM-CSF can itself stimulate an antitumor immune response, resulting in tumor regression in melanoma and prostate cancer. 

Melanins, pigments of diverse origin and chemical function, have been subjects of interest for a long time (Aristotle, in Historia Animalia , 315 B.C.). These natural cosmetics of skin, hair, and feathers usually occur in the form of insoluble fine granules in certain dendritic cells... 

The complex and sometimes redundant phagocyte signaling pathrrays that lead u> production of proinflanunatory, r ulatory and suppressive cytokines and/or chemoldnes, have been the subject of several recent reviews. In vertebrates, a second line of defense, (adaptive irmnunity) is initiated and modulated by the innate immune system throi h the interactions of antigen-presentii cells especially dendritic cells, with specialized B-cells and T-cells, which recognize a wide spectrum of microbial antigens. ... 

The nerve cell, or neuron, is an unusual looking cell (Fig. 8-1). A neuron may be only 0.1 mm in diameter but, may reach lengths of a meter or more. The threadlike extension from the cell body is the nerve fiber. These fibers interconnect in various special areas of the body, including the brain, the spinal cord, and the peripheral nerves. The function of the neuron is to transmit signals, or impulses. The dendrites specialize in receiving excitations, which may be from environmental stimuli (i.e., from peripheral parts of the body, or from another cell). The axon conducts the excitation away from the dendrite area (e.g., to the brain).1 This excitation, or impulse transmission, may be on a subconscious level. Transmissions of which the subject is not consciously aware are the type that control various body functions such as temperature, respiration, blood pressure, and peristaltic movements of the gastrointestinal tract. In addition to the traditional functions of a cell membrane, the membrane of the nerve fiber (the axon) has the role of transmitting the electrochemical impulses that are received from the dendrites. The additional protective device called the myelin sheath basically serves as an electrical insulator. 

In genera] secondary cells have more stringent requirements for separator materials than primary cells. RAM cells typically apply two components, a non woven absorbent and a barrier material. The absorbent material used is formulated fiom polyvinyl alcohol and rayon fibers, acts as mechanical spacer between anode and cathode and provides as an electrolyte reservoir. The barrier is unglycerinated cellulose and prevents zinc dendrites from causing cell shorts. Prior to insertion into the cell the two materials are wound into a tube. Separator materials are selected which are not subject to oxidation in the alkaline electrolyte even at elevated temperatures and which combine chemical and mechanical stability with long life expectancy. 

The dissociated cells and tissue are subjected to only gentle agitation or trituration Trituration pipets are prepared by heat-pohshing to the desired diameter Larger diameter trituration pipets (1-0.75 mm diameter) produce low yields ( 10 cells/tissue block) of viable neurons with some primary dendritic structure The number of neurons can be increased by trituration with smaller diameter pipets although the amount of dendritic amputation is increased, resulting in dendrite-free soma. 

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