Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The C57Bl/Ler-vit.vit mouse grows a black pelage after birth. During successive hair molts, the fur loses its pigmentation. By 6 months of age, most of the fur of the animal is white. The epidermis of the ears and tail also loses its pigmentation. Histologic studies confirm that in the epidermis and hair follicles there is an absence of pigment cells identifiable by various histochemical or electron microscopic techniques. This mouse may be an excellent model in which to study the role of Langerhans' cells and the immune response in the pathogenesis of vitiligo, a study not easily done in humans. From results of prior studies, we postulated that if Langerhans' cells were involved in the destruction of melanocytes, they would be abnormal (either more or less numerous) in number during the active phase of depigmentation and normal in number after depigmentation was complete. To determine whether the Langerhans cell (Ia+/adenosine triphosphatase dendritic epidermal cell) might be involved in destruction of pigment cells, we quantified the number of Ia+ and adenosine triphosphatase dendritic cells in the hair follicles in skin from the ear, abdomen, back, and tail from male C57Bl/Ler-vit.vit mice while the fur and skin were depigmenting and after depigmentation was almost completed. We found that Langerhans' cells were normal in number during depigmentation and were most numerous after depigmentation. Previous studies indicate that Langerhans' cells in these mice are functionally defective and respond poorly to some contact allergens. From these morphologic and functional data, we conclude that Langerhans' cells probably are uninvolved in causing depigmentation in these mice. We also observed that the epithelium of hair follicles has a significantly higher (up to 1600/mm2) population density of Langerhans' cells than interfollicular skin.
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PMID:Langerhans' cells in hair follicles of the depigmenting C57Bl/Ler-vit.vit mouse. A model for human vitiligo. 244 80

This paper describes our own findings on the role of Langerhans' cells in dermatology and discusses literature data on their detection in seven different dermatoses. The skin is an integral part of immune system. During the past 30 years, increasing evidence has been accumulated that the skin contains cellular elements which are needed for the initiation and expression of immune response. Langerhans' cells (LCs) are dendritic cells originating in the bone marrow. They reside mainly within stratified squamous epithelia and constitute approximately 2-4% of epithelial cells. LCs are epidermal antigen presenting cells which play a crucial role in allergic contact hypersensitivity, viral diseases, graft versus host disease and elimination of neo-plastic cell clones. They express antigens conjugated with major histocompatibility complex (MHC) class II positive molecules on their surfaces for presentation to T-helper lymphocytes. LCs cannot be identified in routinely prepared histologic testing but can be visualised at the light microscope level by histochemical and immunologic techniques. Appropriate methods for the detection of Langerhans' cells in dermatology (also shown by our own experience) are histoenzymatic methods of adenosintriphosphatase (ATP-ase), acid phosphatase (AP), alpha-naphthylacetatesterase (ANAE and peroxidase-antiperoxidase immunohistochemistry method with polyclonal S-100 protein antibody (PAP). LCs are the only cells in normal skin with ATP-ase activity. Histoenzymatic methods used in patients with atopic dermatitis, vitiligo, mycosis fungoides, Behcet's disease, lichen ruber planus, psoriasis vulgaris, irritant dermatitis and allergic contact dermatitis demonstrated LSs in epidermis and dermis. ANAE and AP showed concordance and were suitable histochemical markers for LC distribution and macrophages in the dermis in mycosis fungoides, atopic dermatitis, psoriasis vulgaris, irritant chronic dermatitis and Bechet's disease. Our experience of the human skin showed a strong activity of calcium-activated adenosine triphosphatase in LCs. LCs in the guinea pig skin can be demonstrated by Mg++ and Ca++ activated adenosine triphosphatase, but a stronger activity of Ca++ activated adenosine triphosphatase in LCs after irritation. Ca++ ATP-ase as an indicator of energy-dependent pump is the reflection of intracellular calcium level, which is a significant factor for regulating the growth and metabolism of the cells. LCs are found as target cells during the efferent phase of contact allergic reaction. Immunohistochemical methods, define the role of LCs in dermatology more precisely and allow complete immunologic recognition within the epidermis.
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PMID:[Identification of Langerhans cells in dermatology]. 1528 65