Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cornified envelope of keratinocytes is an insoluble structure formed beneath the plasma membrane at the base of the stratum corneum. It is made by cross-linking precursor proteins by a membrane-associated transglutaminase. Using the cornified envelope of cultured human keratinocytes as the immunogen, we obtained a number of monoclonal antibodies which stained epidermis in a variety of ways. The peripheral staining pattern has been associated with several envelope precursors and this has been confirmed by western blots. A mouse IgM monoclonal antibody directed against epidermal basal cell hemidesmosomes was also discovered. By immunofluorescence, the monoclonal antibody produced a strong linear staining of the basement membrane zone and a polar cap on trypsin-dissociated epidermal basal cells. By immunoelectron microscopy, immunoreactants were present in the attachment plaques of hemidesmosomes on guinea pig esophagus. However, no protein reactive with the antibody was detected. This study suggests that an antigen associated with the basal cell hemidesmosomes may be incorporated in the cornified envelope.
J Dermatol 1992 Nov
PMID:Proteins of the cornified envelope. 128 66

Human hair follicles were isolated from the scalp by dispase and collagenase treatment and dispersed into a cell suspension by trypsin. These cells proliferated well and could be subcultured 7 to 8 times. The medium used was MCDB 153 HAA medium further supplemented with some amino acids, hydrocortisone, insulin, EGF, and bovine brain extract. The concentration of Ca++ was adjusted to 0.1 mM. Immunohistochemically, these cells were proved to possess keratins specific to hair forming cells.
J Dermatol 1992 Nov
PMID:In vitro keratin expression of hair cells. 128 73

We recently reported that the mannan component of Trichophyton rubrum cell wall (TRM) has an inhibitory influence on cell-mediated immune function in vitro. We now describe experiments designed to identify the target cell for this effect of TRM. T. rubrum mannan labeled with fluorescein (FITC-TRM) was incubated with peripheral blood mononuclear leukocytes, monocytes, or lymphocytes. Binding and uptake of the FITC-TRM were monitored by fluorescence microscopy and flow cytometry. Approximately 10% of mononuclear leukocytes were stained with this reagent and the fluorescent cells appeared to be monocytes by morphology. Virtually all purified monocytes and no purified lymphocytes stained with FITC-TRM. Flow cytometry to analyze FITC-TRM monocyte-specific binding of FITC-TRM involved the use of a phycoerythrin-labeled anti-CD14 antibody to identify monocytes. The only cells stained with FITC-TRM were those stained with the monocyte-specific antibody. The ability of monocytes to endocytose mannan was assessed by fluorescence microscopy. Cells were exposed to FITC-TRM and washed, and the staining pattern recorded periodically over a 48-h incubation period. After 15 min, staining was homogeneous and involved the entire cell surface; by 30 min, "patching" was observed; by 90 min, bright granules had formed along the cell border and a large number of small granules were present in the cytoplasm; by 8-12 h, the fluorescent granules were enlarged in size and reduced in number; by 24-36 h, the intensity of cytoplasmic fluorescence began to diminish; and, after 48 h, all fluorescent staining had disappeared. An additional feature of staining during the 8-12-h period was the appearance of a large round bright spot in the nuclear region of each cell, which may represent nucleolar staining. A role for "mannan receptors" is suggested by observations that FITC-TRM binding was prevented by unlabeled TRM or pretreatment of the monocytes with trypsin. Our finding that monocytes selectively and specifically bind TRM appears to identify the monocyte rather than the lymphocyte as the target cell for the inhibitory effect of mannan on cell-mediated immune function.
J Invest Dermatol 1992 Jun
PMID:Binding of Trichophyton rubrum mannan to human monocytes in vitro. 131 95

In order to clarify the molecular mechanism of blister formation in oral mucosa in pemphigus vulgaris (PV) comparing with that in epidermis, we analyzed the effects of PV serum on the distribution of keratin intermediate filaments (KIFs) and desmoplakins in oral as well as epidermal cultured keratinocytes by immunofluorescence microscopy using anti-keratin and anti-desmoplakin I/II monoclonal antibodies. After incubation with PV serum for 96 h at 37 degrees C, clusters of anti-keratin positive dots were formed around the nucleus in some of the keratinocytes from normal gingiva and soft palate but not in keratinocytes from tongue and skin, and desmoplakins also changed their distribution from linear arrangement at cell-cell contacts to clusters of dots around the nucleus in gingiva but not in epidermal keratinocytes. The dotted structures similar to those induced by pemphigus serum were formed also by incubation with human plasmin in gingival keratinocytes. However, no dot-formation of keratins was induced in these cells after incubation with trypsin. Furthermore, in epidermal keratinocytes, no keratin-dot formation was observed even after incubation with plasmin or trypsin. These results suggest that the dotted structures of KIFs caused by PV serum and plasmin might be a feature characteristic for the response of oral keratinocytes to PV serum and that there are some distinct differences in susceptibility to, and mode of, bulla formation between oral epithelium and epidermis.
J Dermatol Sci 1992 Jan
PMID:Different effects of pemphigus antibody and plasmin on the distribution of keratin intermediate filaments and desmoplakins between cultured oral and epidermal keratinocytes. 137 6

Immunocompetent cells of the epidermis can interact by the elaboration and recognition of cytokines. Although much new information has been reported concerning the cytokines secreted by keratinocytes, little is known about cytokines derived from Langerhans cells (LC). To address this deficiency, we examined cytokine mRNA profiles in different epidermal preparations from BALB/c mice, taking advantage of the sensitive technique of polymerase chain reaction (PCR), after reverse transcription of mRNA. In assays of epidermal sheets separated from dermis by ammonium thiocyanate, mRNA for IL-1 alpha, IL-1 beta, IL-6, IL-7, tumor necrosis factor alpha (TNF alpha), TNF beta, granulocyte macrophage/colony-stimulating factor (GM-CSF), and macrophage inflammatory protein-1 alpha (MIP-1 alpha) were unequivocally present. By contrast, faint bands were detected for IL-4, IL-5, and interferon gamma (IFN gamma), and no PCR signal was detected for IL-2. Importantly, assays of epidermal cells (EC) dissociated with trypsin revealed similar mRNA profiles. To determine the effects of cell isolation, fluorescence-activated cell sorter (FACS)-purified Ia- EC were first analyzed; all of the previously cited cytokine mRNA were present except for IL-1 beta and MIP-1 alpha. EC depleted of LC by a second technique, lysis using anti-Ia monoclonal antibody and complement, revealed similar profiles, with substantially reduced PCR signals for IL-1 beta and MIP-1 alpha. Finally, FACS-purified LC (Ia+ EC) clearly expressed IL-1 beta and MIP-1 alpha mRNA, a finding that was verified by Southern blotting using internal oligo probes. We conclude that these cell-isolation procedures did not produce substantial alterations in basal mRNA profiles and that LC are the principal source of mRNA for IL-1 beta and MIP-1 alpha among unstimulated EC in mice.
J Invest Dermatol 1992 Nov
PMID:Langerhans cells are the major source of mRNA for IL-1 beta and MIP-1 alpha among unstimulated mouse epidermal cells. 138 44

In a recent series of experiments, we observed that epidermal Langerhans cells (LC) of healthy, non-atopic individuals have the capacity of specifically binding monomeric serum or myeloma IgE. IgE-binding to LC could neither be prevented by pre-incubation of the cryostat sections with monoclonal antibodies (MoAb) against either Fc epsilon RII/CD23 or Fc gamma RII/CD32 nor by the addition of excess amounts of lactose, but could be entirely abrogated by pre-incubation with the anti-Fc epsilon RI MoAb 15-1. A direct testing of the anti-Fc epsilon RI MoAb 15-1 and 19-1 on cryostat sections in an indirect immuno-double-labeling technique showed that, in contrast to eight different anti-Fc epsilon RII/CD23 MoAb, these MoAb react with the majority of CD1a-bearing epidermal cells. At an ultrastructural level, 15-1 immunogold-labeling in the epidermis was confined to the surface of cells exhibiting Birbeck granules. In further experiments, we were able to amplify by polymerase chain reaction (PCR) technology transcripts for the alpha, beta, and gamma chains of Fc epsilon RI from LC-enriched epidermal cells and dermal cells, but not from LC-depleted epidermal cells. Transcripts for the mast cell enzyme tryptase were exclusively found in dermal cell-derived RNA preparations, thus excluding a contamination of the LC-enriched epidermal cell preparations by dermal mast cells. Collectively, these data show that epidermal LC, but not other epidermal cells, express Fc epsilon RI molecules.
J Invest Dermatol 1992 Nov
PMID:Fc epsilon RI mediates IgE binding to human epidermal Langerhans cells. 143 Dec 5

When screening skin cryosections with a panel of monoclonal antibodies (MoAb), we found that the anti-CD69 MoAb Leu-23 reacted with a subpopulation of epidermal dendritic cells, presumably Langerhans cells (LC). The staining intensity was enhanced by gentle trypsin pretreatment of the sections. Flow cytometric analysis of LC-enriched epidermal cells (EC) revealed that nearly all CD1a-bearing LC display anti-CD69 reactivity when tested briefly after termination of the enrichment procedure. Immunoprecipitation experiments showed that isolated LC specifically express a disulphide-linked dimer composed of 26/30kDa subunits that therefore slightly differs from the 28/32kDa CD69 complex described on activated T or natural killer (NK) cells. This difference is probably due to a different post-translational glycosylation pattern as evidenced by Endoglycosidase-F treatment of the immunoprecipitate disclosing the 24-kDa core protein of CD69. When freshly isolated LC-enriched EC were kept in culture, anti-CD69 reactivity gradually decreased but the addition of IFN-gamma to the culture medium sustained the CD69 expression on LC in vitro. These results strongly suggest that resident but not LC recovered from EC cultures bear CD69 moieties. It remains to be seen whether the expression of this antigen can be linked to (a) particular functional property (ies) of intraepidermal LC.
J Invest Dermatol 1992 May
PMID:CD69, an early activation antigen on lymphocytes, is constitutively expressed by human epidermal Langerhans cells. 156 26

Interferon gamma (IFN-gamma) induces human leukocyte antigen (HLA)-DR antigen expression on a variety of cell types, and in human skin cells this induction is inhibited by trypsin inhibitors. Recently a trypsin-like protease was characterized whose activity is required for HLA-DR induction in a hybrid epidermal cell line. Glucocorticosteroids also inhibit IFN-gamma-induced HLA-DR expression, and similarities have been noted between the inhibition by trypsin inhibitors and by glucocorticosteroids. To assess the possibility that glucocorticosteroid inhibition of IFN-gamma-induced HLA-DR expression might be due to induction of an inhibitor of trypsin activity that is re-expression, we examined culture medium supernates (CM) of glucocorticosteroid-treated cells for HLA-DR- and trypsin-inhibitory activities. We report here that CM of glucocorticosteroid-treated H12 cells contain inhibitors of HLA-DR expression and of trypsin activity, but that the two inhibitors are not identical. H12 cells constitutively secrete a greater than 30,000 MW, acid- and heat-stable trypsin inhibitor, whose expression is not modulated by glucocorticosteroid or IFN-gamma, and that does not inhibit IFN-gamma-induced HLA-DR expression. The HLA-DR inhibitor, on the other hand, is present only in CM of glucocorticosteroid-treated cells, is distinct from glucocorticosteroid itself, of a MW less than 500 and does not inhibit trypsin. We conclude, therefore, that the glucocorticosteroid inhibition of IFN-gamma-induced HLA-DR expression is by a mechanism other than secretion of a trypsin inhibitor.
J Invest Dermatol 1992 Jul
PMID:Characterization of a glucocorticosteroid-induced inhibitor of interferon-gamma induction of HLA-DR expression. 160 77

The most frequent site of organ involvement in patients with any form of mastocytosis is the skin. Cutaneous expressions include urticaria pigmentosa, mastocytoma, diffuse and erythrodermic cutaneous mastocytosis, and telangiectasia macularis eruptiva perstans. The cutaneous lesions tend to appear early in life. Although urticaria pigmentosa has been reported in 12 pairs of twins and one set of triplets, the majority of affected individuals have no familial association. Most patients with systemic mastocytosis have skin lesions; however, an occasional patient will have systemic disease with no other skin features than flushing. In lesional cutaneous sites and in non-lesional skin, there is an increase in the number of mast cells. Electron microscopy shows quantitative differences between lesional skin mast cells from patients with and without systemic disease. The mast cells from adult patients with systemic disease have a larger mean cytoplasmic area, nuclear size, and granule diameter. The granules contain predominantly grating/lattice structures. The cutaneous mast cells contain tryptase and chymase. They retain their functional reactivities to relevant secretory stimuli, such as C3a, morphine sulfate, and calcium ionophore A23187. Lesional skin contains histamine, leukotriene B4, prostaglandin D2, 5-hydroxyeicosatetraenoic acid, platelet-activating factor, and heparin. Treatment of the cutaneous manifestations includes the use of H1 and H2 antihistamines, oral disodium cromoglycate, psoralens plus ultraviolet A photochemotherapy, and potent topical corticosteroid preparations.
J Invest Dermatol 1991 Mar
PMID:The skin in mastocytosis. 167 36

Autoantibodies to stratum corneum (SC) occur in virtually all normal adult human sera. These antibodies may be directed against various antigens of the SC. They have been detected by indirect immunofluorescence, passive hemagglutination (HA), immune adherence, and most recently by enzyme immunoassay and immunoblot methods. The purpose of our study was to examine whether antibodies to SC antigens as detected by passive HA are similar to the keratin intermediate filament (KIF) reactive antibodies. SC antigen preparation was prepared from psoriatic scales by the trypsin-phenol-water (TPW) extraction method. KIFs were prepared by 8 M urea extraction of normal callus or psoriatic scales. The anti-SC antibody titers of normal human sera were determined by passive HA before and after absorption with TPW-SC antigen preparation and upon absorption with KIFs. Similarly, titers of anti-KIF antibodies were determined on absorbed and unabsorbed sera by immunoblot assay. The results of this study indicate that the absorption of the sera with KIFs did not affect the titer of antibodies to TPW-extractable SC antigens whereas the titer of KIF antibodies dropped. KIF-reactive antibodies, on the other hand, were not affected by absorption with TPW-SC antigen, whereas the latter absorbed out the corresponding reactive antibodies. These results indicate that antibodies directed against SC antigen are different from the KIF-reactive antibodies.
Arch Dermatol Res 1990
PMID:Stratum corneum antibodies detected by hemagglutination are not directed against keratin intermediate filaments. 169 42


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