Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intracellular acidic compartments serve several functions, including uptake of nutrients, processing and sorting of secreted and membrane-bound proteins, and even entry of viruses into cells. In this study, we examined the distribution of acidic compartments in normal human keratinocytes cultured in serum-free medium. Acridine orange was used to stain acidic organelles (red fluorescence), and adherent cells were evaluated by fluorescence microscopy and by interactive laser cytometry (ILC). Keratinocytes cultured in low [Ca++] (0.15 mM) exhibited morphologic characteristics associated with basal cells; red acidic vesicles in these cells were aggregated around the nucleus, sparing the peripheral cytoplasm. After 24 h of culture in high [Ca++] (1.5 mM) keratinocytes showed morphologic changes associated with differentiated cells, including increased number and dispersal of red vesicles to the periphery of the cytoplasm. Keratinocytes cultured in 0.15 mM [Ca++], but treated with phorbol 12-myristate 13-acetate (PMA, 5-100 ng/ml) to induce terminal differentiation, developed similar features. Incubation in media with either high [Ca++] or PMA also induced radial extension of the microtubule network, suggesting that the distribution of acidic organelles occurs along this network. Finally, crude keratinocyte membranes were evaluated by radioactive assay for the presence of three ion-translocating ATPase activities, plasma membrane Na/K ATPase, mitochondrial ATPase, and vacuolar H+ pump ATPase, the latter being the activity responsible for acidification of intracellular compartments. Both basaloid and differentiated keratinocytes exhibited similar vacuolar H+ pump ATPase activity, as measured by its sensitivity to bafilomycin.
J Invest Dermatol 1992 Jun
PMID:Increased number and microtubule-associated dispersal of acidic intracellular compartments accompany differentiation of cultured human keratinocytes. 153 43

A number of agents have been shown to alter the latent state of herpes simplex virus in murine sensory ganglia. However, it seems that effective triggers of recrudescent disease must act not only to reactivate latent HSV infection, but also to create a favorable environment in the skin for viral replication. The possibility that alteration of the local Langerhans cell population is one way in which effective triggers of recrudescence may act has been investigated. Of the agents tested, which affect latent HSV, only DMSO significantly altered the numbers of ATPase-bearing Langerhans cells in the epidermis, maximally reducing their density by 83% in 48 h. Xylene and retinoic acid had no discernible effect on numbers of ATPase-staining cells over the 4 d tested. However, the extent to which agents reduced ATPase-staining cell numbers did not correlate with their ability to affect the antigen-presenting capacity of the cells in HSV-specific T-cell proliferative assays in vitro. Xylene and retinoic acid markedly reduced the accessory cell function of epidermal cell suspensions, whereas DMSO had no effect.
J Invest Dermatol 1991 Nov
PMID:Effects on murine epidermal Langerhans cells of drugs known to cause recrudescent herpes simplex virus infection in a mouse model. 165 14

Lanthanides are rare earths, elements 55-71 in the periodic table, that are of interest in biologic systems as isomorphic competitors for calcium binding sites. Lanthanides were tested for their inhibitory influence on the Ca++/Mg(++)-dependent ATPase of epidermal langerhans cells in vitro, and on the immunologic function of Langerhans cells in vivo. The trivalent ions of lanthanides, lanthanum, and cerium completely inhibited the ATPase staining of Langerhans cells in vitro. When mice were sensitized with dinitrofluorobenzene on skin sites pretreated with topical lanthanum chloride, and challenged on untreated ear skin, a markedly reduced contact hypersensitivity response was observed. This hyporesponsiveness was found to be antigen specific, and could be passively transferred to naive syngeneic animals recipients by CD4-CD8+ spleen cells. These results suggest that inhibition of the epidermal Langerhans cell surface ATPase by application of topical lanthanum and the induction of antigen-specific immunologic tolerance may be related events.
J Invest Dermatol 1991 Sep
PMID:Inhibition of Langerhans cell ATPase and contact sensitization by lanthanides--role of T-suppressor cells. 167 66

The ATPase-staining of Langerhans cells is usually done on fresh, unfixed biopsy specimens. In the present study, we attempted to stain these cells in previously stored tissues of guinea pig skin. The ATPase activity disappeared after freezing or preservation in formalin or ethanol. In contrast, tissue specimens which had been stored in physiological saline at 4 degrees C stained as well as fresh cells even after 14 days.
J Dermatol 1991 Jul
PMID:The ATPase-staining of Langerhans cells in previously stored skin tissues. 172 54

Langerhans cells (LC) are the principal antigen-presenting cells (APC) of squamous epithelia. We have previously shown that freshly isolated LC (fLC) are able to deliver endocytosed membrane MHC class II molecules into acidic environments, and that this capacity is lost when LC are placed in culture (cLC). Inasmuch as processing of antigens requires their passage through acidic compartments, we undertook the present study to examine the ability of fLC and cLC to take up acridine orange, and to identify proton-translocating ATPases in these cells. Using flow cytometry and fluorescence microscopy, acridine orange was observed to accumulate in acidic compartments in both fLC and cLC. Using a radioactive ATPase assay, crude membrane preparations from both fLC and cLC were shown to possess three types of ion-translocating ATPase, based on sensitivity to the following inhibitors: ouabain (Na+, K+ ATPase), oligomycin (mitochondrial F1F0 ATPase), and bafilomycin (vacuolar-type proton pump ATPase); the last type is responsible for acidification in vacuolar compartments. cLC displayed markedly less (less than 50%) total ATPase activity compared to fLC; however, the relative proportions of specific ATPases were similar in fLC and cLC. Combined use of the three inhibitors resulted in abrogation of only 25-40% of the total ATPase activity. Finally, treatment of LC with bafilomycin inhibited both acridine orange uptake and acidification of internalized HLA-DR molecules. These results confirm the ability of both fLC and cLC to acidify vacuolar compartments, thereby suggesting that lack of acidification of endocytosed membrane class II molecules in cultured cells is due to alternative routing to non-acidic organelles.
J Invest Dermatol 1991 May
PMID:Vacuolar acidification and bafilomycin-sensitive proton translocating ATPase in human epidermal Langerhans cells. 182 37

Isolated mitochondria were used to determine what causes anthralin inhibition of oxidative phosphorylation. In good agreement with other results, the rate of oxygen consumption was not modified by anthralin when mitochondria were first uncoupled with FCCP, suggesting that only the last steps of the process leading to ATP phosphorylation are implicated. No effects were found at the level of the ATPase and the Pi carrier in contrast with a competitive inhibition of the ADP/ATP translocator. These experiments suggest an atractyloside-like effect to explain the action of anthralin on mitochondria.
Arch Dermatol Res 1991
PMID:Effects of anthralin on mitochondrial bioenergetics. 183 Oct 19

In the last years a new therapy of psoriasis was developed, which consists in a treatment with salt solutions, resembling the water of the Dead Sea, and ultraviolet light (Tomesa-therapy). We studied the influence of the used salt on ATPase positive epidermal Langerhans cells in murine ear skin. An irreversible partial reduction of the Langerhans cell ATPase was found after salt treatment of separated epidermis or of full skin preparations. These results may have implications for the optimization and broader application of this therapy.
Dermatol Monatsschr 1990
PMID:[The effect of Tomesa therapy on epidermal Langerhans cells in experimental animals]. 214 11

The role of Langerhans cells in the pathogenesis of nonsegmental type vitiligo is still unknown. In this study, biopsies were taken from 26 patients at various stages of nonsegmental type vitiligo and morphometrically observed to investigate the kinetics of Langerhans cells in patients at various stages of the disease. A marked depletion of OKT6-positive and ATPase-positive epidermal dendritic cells was noted in patients with active nonsegmental type vitiligo. A repopulation of both OKT6-positive and ATPase-positive epidermal dendritic cells was noted in patients with stable nonsegmental type vitiligo. Profound depletion of epidermal OKT6-positive and ATPase-positive dendritic cells was noted in patients with repigmenting nonsegmental type vitiligo receiving treatments involving topical use of 0.05% Fluocinonide cream or PUVA photochemotherapy. Transmission electron microscopy confirmed the absence of epidermal dendritic cells (Langerhans cells and intermediate cells) in patients with active and repigmenting nonsegmental type vitiligo. In active nonsegmental type vitiligo, two possible explanations are proposed for the depletion of OKT6-positive and ATPase-positive epidermal dendritic cells (presumptive Langerhans cells): 1) the cells are destroyed by cytotoxic factors released during the course of destruction of melanocytes in active vitiligo, and/or 2) they leave the epidermis and migrate to regional lymph nodes to present certain antigens which are released from certain destroyed epidermal cells (keratinocytes or melanocytes) during the course of active vitiligo. The repopulated epidermal Langerhans cells may result from phenotypically transformed dermal dendritic cells in the depigmented lesions of patients with stable vitiligo. Since various therapies which result in repigmentation deplete the density of epidermal Langerhans cells markedly, it is suggested that depletion of epidermal Langerhans cells in stable vitiligo may aid in repigmentation. It is also proposed that the repopulated epidermal Langerhans cells may play a role in inhibiting the proliferation of epidermal melanocytes in depigmented lesions of stable vitiligo, thus various methods of treatment which deplete the Langerhans cells may eventually aid in the repigmentation of nonsegmental type vitiligo.
J Dermatol 1990 May
PMID:Depletion and repopulation of Langerhans cells in nonsegmental type vitiligo. 238 Apr 33

Morphology, phenotype, and enzyme activity of highly enriched (80%) unlabeled human epidermal Langerhans cells (LC) have been studied, with emphasis on changes during a short-term culture of three days in vitro. All freshly isolated LC contained Birbeck granules and expressed high levels of CD1a, CD1c, and MHC class II molecules HLA-DR, -DP, and -DQ. They have a weak to moderate expression of RFD1, C3biR, Fc gamma R, p 150/95, MHC class I molecules HLA-ABC, and of the adhesion molecules LFA-3 and ICAM-1, whereas no expression of LFA-1 and several monocyte/macrophage markers were detected. Human LC undergo profound changes during in vitro culture. Birbeck granules, C3biR, Fc gamma R, and p 150/95 were completely lost and the expression of CD1a and CD1c was markedly decreased or lost. Expression of molecules that have essential functions in antigen presentation remained present at the same level (MHC class II molecules and ICAM-1) or was markedly enhanced (LFA-3 and MHC class I). Highly remarkable was the dramatically enhanced expression of interdigitating cell marker RFD1. The monocyte/macrophage markers initially absent remained absent and the enzyme activity initially present (including ATPase and nonspecific esterase) remained present. In conclusion, the results in this report stress rapid alterations of human LC during in vitro culture, resulting in transformation into cells that have phenotypical characteristics of potent antigen presenting cells that resemble interdigitating cells.
J Invest Dermatol 1990 Feb
PMID:Human epidermal Langerhans cells undergo profound morphologic and phenotypical changes during in vitro culture. 240 65

The distribution of ATPase-positive Langerhans cells (LC) was investigated in 117 specimens of normal adult human skin and mucosa taken from different areas of the body. Although there were significant variations in the numbers of LC in each area examined, skin from the face and neck contained the highest density of cells (976 +/- 30.93/mm2). The densities of LC in trunk skin (740 +/- 28.97/mm2), scalp (693 +/- 69.56/mm2) and arm or leg skin (640 +/- 40.95/mm2) were similar. Buccal mucosa had significantly fewer LC (567 +/- 42.94/mm2) than trunk skin, and sacrococcyx skin and palm and sole skin displayed the smallest number of these cells (267 +/- 56.14/mm2 and, 189 +/- 19.15/mm2 respectively). No ATPase-positive LC were detected in the centre of two corneal specimens.
Br J Dermatol 1985 Dec
PMID:Distribution of ATPase-positive Langerhans cells in normal adult human skin. 242 Mar 51


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