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

Experiments were conducted to determine whether ultraviolet (UV) radiation exerts its effect through the generation of oxygen intermediates on Langerhans cells (LC). Guinea pigs were exposed to one single dose of UVB (0.9-2.7J/cm2), and biopsy specimens were taken 5 days after the irradiation. The population of LC was evaluated using ATPase-stained epidermal sheets. These exposures reduced the number of LC to 20-25% of the original density. On the other hand, superoxide dismutase (SOD) (0.02-0.2 mg), a scavenger of superoxide anion, which had been injected intradermally just before UV radiation, significantly prevented the depletion of LC, although not completely (37-40% of the original density). The injection immediately after the exposure was still significantly effective, but less so. Other scavengers of oxygen intermediates including catalase, D-mannitol, and L-histidine revealed no detectable effect. A single exposure of UVB at doses of 0.3-0.6 J/cm2 did not deplete the ATPase-positive LC. However, the same dose of UVB reduced the number of LC to 70%, when exposed after the injection of an SOD inactivator, diethyldithiocarbamate, possibly due to inactivation of physiologically existing SOD. These observations indicate that oxygen intermediates such as superoxide anion or its subsequent species are generated by UV radiation exposure and damage the epidermal LC.
J Invest Dermatol 1987 Jun
PMID:Oxygen intermediates are involved in ultraviolet radiation-induced damage of Langerhans cells. 303 31

The application of a sensitizing dose of urushiol on a dinitrofluorobenzene (DNFB)-treated skin area significantly diminished the intensity of the urushiol challenge test in guinea pigs. Furthermore, the animals which had been first exposed to urushiol through DNFB-treated skin failed to become sensitized in a second sensitization attempt even when painted on a previously untreated area. This tolerance is hapten-specific and may be reversed by treatment with cyclophosphamide (200 mg/kg) shortly before another contact sensitization attempt to urushiol. In a previous work, we have shown that most of the Langerhans cells present in the DNFB-treated skin area are ATPase-negative and that there exists a link between the membranous ATPase system and the formation of Langerhans cell granules. The latter seem to develop in the course of a mechanism of adsorptive pinocytosis during which ATPase activity "disappears." Thus we suggest that the "unavailability" of ATPase-negative Langerhans cells for adequate processing a second hapten may result from the incapacity of cells lacking their ATPase system to activate the intracellular events that depend on this system and that normally lead to sensitization.
J Invest Dermatol 1985 Jul
PMID:Induction of tolerance to urushiol by epicutaneous application of this hapten on dinitrofluorobenzene-treated skin. 315 3

To establish if epidermal Langerhans cells (LC) are related to spleen dendritic cells, we have considered the morphology, phenotype, and function of the 2 cell types in culture. Cultured LC could be partially enriched (up to 50%) on the basis of 2 simple physical properties: nonadherence to plastic, and low buoyant density in dense albumin columns. The morphology of cultured LC and spleen dendritic cells were similar. In particular both cell types had many cell processes and/or veils, and cultured LC lost their distinguishing Birbeck granules. Freshly isolated LC exhibited nonspecific esterase and ATPase, as well as the F4/80 (alpha-macrophage) and 2.4G2 (alpha-Fc receptor) antigens. However all these traits were lost in culture, while Ia and Mac-1 antigens persisted. As a result, the cytochemical and antigenic phenotype of LC became similar to spleen dendritic cells. The one exception was that LC lacked the 33D1 dendritic cell antigen. The function of LC at first differed from spleen dendritic cells in that fresh LC were weak stimulators of T cell proliferation in the mixed leukocyte reaction and in sodium periodate-induced mitogenesis. However, stimulatory activity per cell increased at least 30 fold in culture so that by 2-3 days, LC were 3-10 times more potent than dendritic cells. Maturation of LC function was radioresistant and was accompanied by a small increase in cell surface Ia antigens. Although LC have been likened both to lymphoid dendritic cells and to macrophages, our data suggest a different conclusion. LC seem to be dendritic cell precursors and are immunologically immature. Possibly, lymphoid dendritic cells are in general derived from substantial pools of precursors in nonlymphoid tissues, such as epidermal LC.
J Invest Dermatol 1985 Jul
PMID:A comparison of murine epidermal Langerhans cells with spleen dendritic cells. 315 9

We have devised, in guinea pigs, an improved ATPase technique which enables one to proceed from light to electron microscope study while preserving, on the ultrastructural level, the various membranous structures, in particular the Langerhans cell (LC) granules. Using this method, we have been able to confirm the action of acute, low-dose UVB on the surface enzymatic marker, ATPase. Moreover, this study has shown that the ATPase-negative LC contain abnormal LC granules or, more often, are deficient in LC granules. In a previous work, we have shown that, after epicutaneous application of a hapten, one successively observes an extensive adsorptive pinocytosis process, the disappearance of the membranous ATPase system, and the appearance of LC granules in the cytoplasm. Therefore we may suppose that, after UVB irradiation, the disappearance of the ATPase system and/or the possible alteration of the adsorptive pinocytosis process interrupts or alters the formation of LC granules. These successive events might play a vital role in the formation of the hapten--carrier protein-Ia antigen complex. In their absence in a large number of LC, following UV irradiation, epicutaneous application of a hapten would lead to the development of a state of immune tolerance.
J Invest Dermatol 1985 Aug
PMID:ATPase and morphologic changes induced by UVB on Langerhans cells in guinea pigs. 316 Jul 91

It was recently discovered that murine epidermal Langerhans cells (LC) changed significantly in function and phenotype when maintained in culture. Notably, accessory cell function for primary immune responses increased while cytologic markers like ATPase, nonspecific esterase, and Birbeck granules were lost. To further analyze LC differentiation, we used flow cytometry and a panel of 22 monoclonal antibodies to quantitate changes in surface antigens at the single-cell level. A striking change was a fivefold increase in the amount of Ia antigens (which are expressed on class II MHC products) during the first day of culture. The increase was evident within 3 h and reached a plateau at 15-24 h. Both I-A and I-E products behaved similarly. The increase in Ia was blocked by 1 microgram/ml cycloheximide. Expression of other surface antigens was then monitored on Ia+ LC by two-color flow cytometry. Low levels of class I (H-2D and H-2K) MHC products were detected on freshly isolated LC, and these antigens also increased severalfold during the first day of culture. Fc receptors (identified with the 2.4G2 mAb) and the F4/80 macrophage antigen decreased, as reported previously. Three antigens that were detected in fresh suspensions were expressed at constant levels in culture. These were the C3bi receptor and the pan leukocyte and interdigitating cell antigens. Several leukocyte antigens that were not found initially on LCs did not appear, including B220 anti-B cell, 33D1 anti-dendritic cell, and CD4, CD5, CD8 T-cell specificities. We conclude that the surface of cultured LCs undergoes selective changes in culture. As a result, the cells are rich in Ia and H-2 and have detectable C3bi receptors, but have little or no LFA-1, Ti, CD4, 5, and 8, 33D1, 2.4G2, F4/80, and B220 antigens.
J Invest Dermatol 1988 Mar
PMID:Quantitation of surface antigens on cultured murine epidermal Langerhans cells: rapid and selective increase in the level of surface MHC products. 327 34

We studied the recovery phase of immune response-associated (Ia)-positive or ATPase-positive epidermal Langerhans cells (ELCs) after ultraviolet B (UVB)-induced depletion by using mouse ear epidermal sheets. An area 3 mm in diameter was irradiated with 300 nm UVB light (40 mJ/cm2). A time sequence study was carried out to 56 days. During this period the Ia-positive ELC population increased stepwise, i.e., first a rapid increase between day 7 and day 14, which we called the early recovery phase, and next a gradual increase between day 42 and day 56, which we called the late recovery phase. During the early recovery phase, we found polymorphous ELCs in the irradiated area which were giant or normal in size, dendritic or round in shape, and single or paired in distribution. Electron microscopy revealed some of round and some of paired ATPase-positive ELCs to be in metaphase or telophase of mitotic division. Within the entire observation period of our study, there was no evidence suggesting migration of ELCs from hair follicles or from the nonirradiated epidermis. These findings indicated that mitosis of ELCs contribute to their repopulation during the early recovery phase.
J Invest Dermatol 1987 Jun
PMID:Epidermal Langerhans cells undergo mitosis during the early recovery phase after ultraviolet-B irradiation. 347 41

We studied 67 patients with multiple contact allergies to determine whether there was an association of this state with any particular HLA antigen. HLA-A, -B and DR antigens were typed by standard serological methods. There was no significant HLA association, although there was an increased frequency of DR4 in those patients who included nickel as one of their sensitivities (64% compared with 33% in controls), and an increase in DR6 in those patients who included sensitivity to a rubber accelerator (45% compared with 16% in controls). However, when the probabilities were corrected for the number of HLA antigens tested and the number of substances in the patch test battery, these associations were no longer statistically significant. We also examined the morphology and numbers of Langerhans cells in epidermal sheets from six subjects with multiple allergies. There were no differences in appearance or numbers of Langerhans cells stained for ATPase, compared with 20 non-allergic controls.
Br J Dermatol 1986 Oct
PMID:HLA antigens and Langerhans cell density in contact dermatitis. 349 Aug 76

Cutaneous immune reactions are known to show sexual dimorphism. Langerhans cells (LCs) are bone marrow-derived immune cells in the epidermis and are essential to immune reactions in the skin. In the present research, a study was made of the differences in LC density of male and female mice. Epidermal sheets were separated from the skin of the glabrous part of hind limbs and ears of specific pathogen-free (SPF) mice by ethylenediaminetetraacetic acid (EDTA) treatment and stained for adenosine triphosphatase (ATPase) activity. The density of LCs of hind limb epidermis in male C57BL/6 (823 +/- 20/mm2) and BALB/c (1689 +/- 66/mm2) mice was significantly less than that in females (1363 +/- 52/mm2, p less than 0.001; 2249 +/- 105/mm2, p less than 0.001, respectively). Langerhans cell density in the ears of male C57BL/6 (465 +/- 24/mm2) mice was also significantly less than that in females (542 +/- 17/mm2, p less than 0.02). Although ovariectomy failed to bring about any change in the LC density of hind limb epidermis in female C57BL/6 mice, the LC density in male C57BL/6 mice increased significantly at 4 weeks following orchiectomy (sham operation, 564 +/- 27/mm2; castration, 1179 +/- 49/mm2, p less than 0.001). These results indicate that mouse epidermal LC density depends on sex, i.e., male mice have fewer LCs than female mice. The reduction in LC density in males may possibly be caused by the testis.
J Invest Dermatol 1987 May
PMID:Sex differences in the densities of epidermal Langerhans cells of the mouse. 357 27

The effect of topical PUVA on the disease course and immunity of T. mentagrophytes dermatophytosis was investigated in guinea pigs. Animals which had been inoculated on nontreated skin showed mild erythematous lesions with scaling in a few days and then developed the most intense reaction between days 10 and 14. The lesions resolved completely by the third week. On the other hand, animals which had been inoculated on the PUVA-treated sites showed only mild squamous, erythematous lesions until the fourth postinfective week, when the intense reaction began to appear. Complete regression was observed by the fifth week in these animals. Trichophytin tests performed on the 14th day were positive in the guinea pigs of non-treated group, while negative in the PUVA-treated animals. The latter group revealed a positive reaction on the fifth week. PUVA did not show inhibitory effect on the sensitization by intracutaneous injection of trichophytin antigen. The PUVA treatment depleted the ATPase-positive Langerhans' cells. These results indicate that PUVA treatment suppresses the immunity of dermatophytosis and delays the spontaneous resolution of the lesions, and suggest that the Langerhans' cell is involved in the development of cell-mediated immunity in experimental dermatophytosis.
Arch Dermatol Res 1986
PMID:The inhibitory effect of PUVA on the immunity of experimental dermatophytosis in guinea pigs. 374 Sep 41

Langerhans' cells (LCs) appear to be altered in diseases that express a depressed cellular immune response. We measured the density of LCs in the skin of patients with the disseminated form of paracoccidioidomycosis. The study was performed using adenosine triphosphatase staining of epidermal sheets. Sixteen patients with paracoccidioidomycosis were evaluated. They had a highly significant reduction in LCs (LCs, 323 +/- 135/mm2) when compared with the number (LCs, 689 +/- 204/mm2) found in the control subjects. Morphological alterations of these cells were noted in patients with low numbers of LCs. These findings may reflect the depressed cellular immunity secondary to the infection with Paracoccidioides brasiliensis.
Arch Dermatol 1987 Apr
PMID:Langerhans' cells in paracoccidioidomycosis. 382 79


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