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)

A method is described for the isolation of human epidermal Langerhans cells (LC). Following the disaggregation of the epidermis by gentle trypsinization, the cell suspension is incubated with the fluorescein-conjugated monoclonal antibody OKT6. Using a fluorescence-activated cell sorter, a subpopulation is selected on the basis of positive fluorescence and low forward-scatter, the latter parameter reducing contamination by LC-keratinocyte clusters. The LC averaged 1.7% of the original epidermal preparation. The purity averages 83% as judged either by OKT6 binding or by ATPase activity. Biochemical measurements indicated that the activity of lysosomal enzymes was low with the exception of alpha-mannosidase, which was about 12-fold higher than that of the keratinocyte. The activities of 3 enzymes of intermediary metabolism suggest that the utilization of glucose by the LC is considerably greater than that of the keratinocyte.
J Invest Dermatol 1985 Sep
PMID:Isolation and preliminary biochemical characterization of the human epidermal Langerhans cell. 403 35

Guinea pig skin was depleted of Langerhans cells (LC) as assessed by ATPase and Ia staining using several techniques. The LCs were depleted either by tape-stripping or exposure of the animals to UV-B or UV-C radiation. Guinea-pigs were sensitized to 2,4-dinitrochlorobenzene (DNCB) by application of the sensitizer to the epidermis depleted of LC. Minimally suppressed contact reactions were found in animals exposed to both wavelengths of radiation, but this was shown to be a systemic rather than a local effect. Tape-stripping did not alter the degree of contact sensitivity when guinea-pigs were sensitized with a large dose of DNCB. When a non-sensitizing dose of DNCB was applied to the ear depleted of LC by tape-stripping, contact sensitivity resulted. Although the depletion of LCs was 97% following UV-B, 93% with UV-C and 78% after tape-stripping, at no time were LCs completely absent from the epidermis.
Br J Dermatol 1985 Sep
PMID:Effect of depletion of epidermal dendritic cells on the induction of contact sensitivity in the guinea-pig. 406 65

The key role of the Langerhans cell (LC) in the immune response and particularly in allergic contact dermatitis is well documented. At first, we determined in the epidermis of the forearm by a non-sensitized adult volunteer, the variations in the density of LC (number/mm2), following the application of various chemicals: nickel sulphate 5 p. 100; erythromycin base 2 p. 100, 2,4-dinitro-1-chlorobenzene (DNCB) 0.02 p. 100 in white petrolatum. Measurements were made at 6, 24 and 48 hours. In a second stage, the volunteer was sensitized to DNCB and a similar study was performed after application of DNCB 0.02 p. 100 at 6 and 24 hours. Normal skin was used as control. The epidermis was obtained by using the suction blister method: LC were identified by the enzymatic ATPase technique and by the immunocytological OKT6 technique. Surfaces were determined by means of a computerized digital tablet. Results obtained with the ATPase technique cannot be interpreted. The density of LC determined by the OKT6 is not significantly modified when the various chemicals are applied on the skin of the non-sensitized volunteer. After sensitization to DNCB, the number of LC is significantly increased after 6 hours of application of DNCB 0.02 p. 100 but not after 24 hours. Further studies are needed to confirm these preliminary observations.
Ann Dermatol Venereol 1985
PMID:[Quantitative study of the number of Langerhans cells per surface unit in allergic contact eczema]. 409 5

Increase in masses of mixed (myelinated and nonmyelinated) nerve are observed in the dermis of clinically normal skin of patients with multiple endocrine neoplasia, type 2b (MEN 2b). Preliminary histochemical studies revealed nucleoside triphosphatase and nonspecific acid esterase. Electron microscopy showed axonal organelles, mild degeneration of axons, and numerous axons unassociated with Schwann cells. The normal-appearing skin in MEN 2b seems to contain abnormal nerve tissue development equally with the mucosal and the gastrointestinal tract.
J Invest Dermatol 1982 Nov
PMID:Cutaneous neuropathology in multiple endocrine neoplasia, type 2b. 612 65

Langerhans cells (LCs) in mammalian epidermis possess the ectoenzyme Ca++/Mg++-dependent adenosine triphosphatase (ATPase), which has served as a useful histochemical marker for these dendritic cells in a variety of tissue preparations. Since ATPase represents only one of several potential cell surface polyphosphatases, we investigated the capacities of 3 related adenine nucleotide substrates to identify rodent epidermal LCs. Cell surface ATPase activity was not inhibited in the presence of ouabain and was observed to be strictly divalent cation-dependent, with complete interchangeability between Ca++ and Mg++. Optimal staining in the presence of either cation occurred at a 20 mM concentration. Substrate concentration dependence was also observed, with optimal staining at 0.33 mM adenosine 5'-triphosphate (ATP). On an equimolar basis, however, adenosine 5'-diphosphate (ADP) was superior to ATP for the identification of LCs both in whole mounts of epidermis and in suspensions of disaggregated epidermal cells. The substrate adenosine 5'-monophosphate (AMP) stained follicular epithelial cells in both rodent species but failed to identify epidermal LCs in the mouse and only weakly stained these dendritic cells in rat epidermis. We conclude from these studies that ADP demonstrates greater specificity for LC surface polyphosphatase activity than ATP and that the inadvertent inclusion of AMP during identification procedures for epidermal cell suspensions will falsely identify cells other than LCs.
J Invest Dermatol 1984 May
PMID:Rodent epidermal Langerhans cells demonstrate greater histochemical specificity for ADP than for ATP and AMP. 615 Sep 59

The distribution of epidermal Langerhans cells (LC) in erythrokeratodermia variabilis (EKV) was investigated using enzyme-histochemical (ATPase) and immunohistochemical (anti-T6 and anti-HLA-Dr) techniques. Biopsy specimens from lesional skin of five patients were examined before and 8 weeks after treatment with etretinate (RO 10-9359). In addition, electron microscopy studies were carried out in two of these cases. The number of ATPase-positive dendritic cells in lesional epidermis appeared to be remarkably reduced in comparison with normal skin from healthy subjects. After treatment, the number of ATPase-positive dentritic cells had increased but still remained below normal values. Similar but less striking results were found for anti-T6-stained specimens. The HLA-Dr antigen appeared to be unsuitable as a marker for comparative quantitative studies because of the highly variable expression of this antigen in the control specimens. Electron microscopy studies revealed LC in the basal and suprabasal layers of the lesional epidermis. Both before and after treatment, the LC exhibited a normal ultrastructure. In view of the clinical and histologic normalization of the skin lesions during treatment, these findings suggest that the decreased number of epidermal LC may be related to the abnormal keratinization that occurs in EKV.
Arch Dermatol Res 1982
PMID:Epidermal Langerhans cells in erythrokeratodermia variabilis. Histochemical and ultrastructural investigations before and after treatment with etretinate (RO 10-9359). 618 1

ATPase histochemistry was used to examine Langerhans cell (LC) populations in the skin of young persons with no evidence of solar damage and older adults with chronic actinically damaged skin. The number of LC was significantly decreased in the older age group. Significantly fewer LC were observed in exposed vs covered skin in the older individuals; no such disparity was noted in the younger subjects. Morphologic alterations in ATPase-positive cells were noted in some specimens, most of which were taken from the exposed skin of elderly persons. The results suggest an independent, although possibly additive, quantitative and qualitative influence of aging and chronic sun exposure on the LC population. Decreased numbers of LC in the sun-damaged skin of elderly individuals may play a critical permissive role in the development of cutaneous carcinoma.
J Invest Dermatol 1984 Mar
PMID:The effect of aging and chronic sun exposure on human Langerhans cell populations. 619 32

The possible relation between the therapeutic action and Langerhans cell (LC) depleting effect of psoralen photochemotherapy (PUVA) was investigated in 9 psoriatic patients by parallel recording of the clinical status, using the psoriasis area and severity index ( PASI ), and the epidermal LC counts of uninvolved skin, using light (ATPase staining) and electron microscopy (EM). Both light and electron microscopically recorded LC numbers decreased significantly during the PUVA course of, on the average, 21 exposures and a mean cumulative UVA dose of 77 J/cm2. At the end of the treatment period, both the PASI score and the light microscopically recorded LC density had reduced to about one-tenth of original, i.e., from 7.5 +/- 5.7 to 0.8 +/- 0.8 points and from 787 +/- 70 to 60 +/- 48 cells/mm2, respectively. After cessation of the PUVA course, the PASI scores remained low during the 3-7 week follow-up period, while the LC counts returned to normal, and even exceeded the starting value by 12%. Although a possible functional impairment of LC in the post-PUVA period cannot be excluded, the data are interpreted as speaking against the hypothesis that the therapeutic action of PUVA would be mediated through its LC effects.
J Invest Dermatol 1984 Jun
PMID:Relation of antipsoriatic and Langerhans cell depleting effects of systemic psoralen photochemotherapy: a clinical, enzyme histochemical, and electron microscopic study. 620 3

Epidermal Langerhans cells (LCs) possess surface markers and functional attributes which identify them as being of macrophage/monocyte lineage, and recent evidence documents their participation in certain immune process which occur in skin. To assess the role of LCs in lupus erythematosus (LE), a disease in which immune system dysfunction predominates, human epidermis from patients with cutaneous LE was studied with 3 LC surface markers: ATPase activity, HLA-DR and OKT-6 antigens. Suction blister top epidermal skin biopsies from patients with 3 clinical types of cutaneous LE exhibited similar features: LCs were less dendritic, they were more irregularly distributed, and they were present in fewer numbers when compared with those in adjacent normal skin. These changes contrasted with those observed in diseases with similar lichenoid histopathological features. LCs appeared increased in number in lichen planus. LCs in skin lesions from one patient with dermatomyositis exhibited similar morphologic alterations, but surface densities and distributions were preserved. Disaggregated epidermal cells from skin lesions of patients with cutaneous LE induced allogeneic lymphocyte proliferation as efficiently as did cells from nonlesional skin, indicating that the morphologic alterations observed were not associated with a decreased alloantigen presenting capacity. These studies have demonstrated that epidermal LC populations in 3 clinical types of cutaneous LE are perturbed in a manner not seen in 2 other lichenoid skin diseases, although these changes were not associated with an altered capacity of such cells to stimulate proliferation by allogeneic lymphocytes.
J Invest Dermatol 1982 Oct
PMID:Epidermal Langerhans cell involvement in cutaneous lupus erythematosus. 621 51

Epidermal Langerhans cells (LCs) function as the antigen-presenting cells in such cutaneous cell-mediated immune responses as contact hypersensitivity and in the mixed epidermal cell-lymphocyte reaction. They have also been implicated in the immune response in skin allograft rejection. Since organ culture of thyroid and pancreas has been shown to prolong allograft survival, presumably through the loss of antigen-presenting cells, we examined the effect of skin explant culture on LC survival. Human skin explants were placed in organ culture and examined serially as whole mounts of epidermis for the presence of LCs as judged by ATPase activity, and OKT-6 and HLA-DR antigens. Although we observed morphologic changes and an absolute reduction in the number of positively stained cells, culture for up to 28 days failed to deplete explants of these cells. Langerhans cells were also sought in the epidermal outgrowths that develop peripheral to the original explants. They were never seen in the area beyond 0.3 mm from the explant edge. Organ culture of skin thus provides a means to explore the contribution of LCs to skin allograft rejection by comparing the immunogenicity of epidermal portions of the explant with the epidermal outgrowth.
J Invest Dermatol 1982 Nov
PMID:Differential distribution of Langerhans cells in organ culture of human skin. 621 52


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