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

Pilated Neisseria gonorrhoeae of colony type 1 (T1) and non-pilated bacteria of colony type 4 (T4) were observed by transmission (TEM) and scanning electron microscopy (SEM). No pili were observed on T4 gonogocci, but two types of pili--straight, type a, and bent, type b--were seen on T1 by TEM. When incubated with human sperum and examined by either TEM or SEM, T1 gonococci were seen to attach by individual pili, by several pili wound together as a rope, or by direct contact. Gonococci from T4 colonies attached only by direct contact. Treatment with typsin (1 mg/ml) damaged or removed pili from gonococci. After incubation with trypsin, attachment of pilated gonococci to sperm was decreased significantly, but such treatment did not affect attachment of non-pilated gonococci. Incubation of gonococci from either colony type in 0.1 mmol/l ferric nitrate, followed by incubation with sperm, significantly increased attachment of only T4 bacteria. No pili were seen on T4 gonococci treated with ferric nitrate; thus, it appears that factors other than pili alone are concerned in attachment of these gonococci to sperm.
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PMID:Attachment of Neisseria gonorrhoeae to human sperm. Microscopical study of trypsin and iron. 3 83

The relationship between the major histocompatibility complex (MHC) and functional receptors on the surface of human lymphocytes was studied. HLA antisera were tested for their effect on the formation of E-, EA-, and EAC'-rosettes by human peripheral blood lymphocytes (PBL). Antisera to various HLA specificities inhibited the formation of EAC'-rosettes, but had no effect on the formation of E-rosettes. The formation of EA-rosettes was inhibited by HLA antisera only in part among the individuals tested. Anti beta2-microglobulin serum resembled HLA antisera in its effect on the formation of the various rosettes. HLA determinants and complement receptors are different entities on the cell surface since elimination of complement receptors by trypsin treatment does not seem to affect the expression of HLA antigens on the cell surface. It is suggested that EAC' receptors are located close to HLA determinants.
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PMID:Association between HLA determinants and complement receptors on human lymphocytes. 7 Aug 64

Sheep erythrocytes (E) which, with or without certain treatments, are currently used as "immunological reagents" to detect cells with specific receptors (by rosette-formation) have been partitioned in two-polymer aqueous-phase systems selected so as to reflect charge-associated or lipid-related membrane surface properties. We have found that the partitioning behavior of E is not affected in these phases by reacting the cells with anti-E antibody (either IgG or IgM), forming EA. The additional binding of complement to the cell-antibody complex, forming EAC, results, however, in a marked decrease in the partition coefficient, K. Apparently both the charge-associated and hydrophobic properties reflected by partitioning remain accessible to the phase polymers when the cells are coated with antibody, but are not with the addition of complement. It is interesting that EA can still rosette with T-lymphocytes (14), a property of E, while the additional coating with complement results in EAC which does not appreciably do so (26). Neuraminidase or trypsin treatments of E, which yield Es having quite different rosetting properties with T-lymphocytes (14), cause increased Ks and unchanged Ks, respectively, in phases reflecting lipid-related surface properties. Either treatment causes reduced Ks of E in charged-phase systems. Neuraminidase treatment also results in a reduced electrophoretic mobility of E, while trypsin treatment is not detectable by cell electrophoresis (25). We are currently studying the possible usefulness of employing cell electrophoresis and cell partitioning in charged-phase systems jointly to obtain information on events occurring at the shear plane versus those occurring deeper in the membrane.
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PMID:Membrane surface properties of sheep erythrocytes, an immunological reagent, after different treatments as reflected by partition in two-polymer aqueous phases. 9 74

E, EA and EAC rosetting techniques and Ig fluorescence were used in a study of receptor sites in cryostat sections of lesions through the spectrum of leprosy, and for comparison in some other mycobacterial and granulomatous lesions. Anti-C3, and trypsin were used as blocking agents. Lymphocytes in borderline lepromatous leprosy produced EA adherence and IgG fluorescence indicating B type cells. Lymphocytes in tuberculoid leprosy produced neither E or EA adherence and no fluorescence; these cells were presumed to be T cells. EAC and EA adherence was more marked in areas of macrophage infiltration, where there were few lymphocytes, than over the lympocytes themselves. Two distinct patterns emerged: (i) EA binding together with IgG fluorescence was seen in active lepromatous leprosy and could be localised to the surface of individual macrophages, and (ii) EAC binding together with IgM fluorescence was seen in the granuloma of tuberculoid leprosy and sarcoidosis, but could not be definitely related to cell surface; rather it was diffusely spread over the whole granuloma; EAC adherence was diminished by anti-C3 serum. Trypsin removed EA binding completely, but only diminished EAC adherence. It is suggested that the EA pattern indicates immunoglobulin receptors on macrophage and lymphocyte surfaces: and that the EAC binding (which is stronger than EA) involves C3 and IgM receptors at extracellular sites as well as C3 receptor sites on epithelioid cell surfaces. EA and EAC binding were enhanced in borderline tuberculoid leprosy in reaction and erythema nodosum leprosum, suggesting that immunoglobulin and complement receptor sites increase in number with enhanced hypersensitivity.
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PMID:Surface markers on lymphocytes and cells of the mononuclear phagocyte series in skin sections in leprosy. 72 93

The effects of various treatments on erythrocyte shape, surface, cell coat and calcium binding sites have been investigated by means of high voltage electron microscopy (HVM), scanning electron microscopy (SEM) and conventional electron microscopy (TEM). Papain caused the formation of small blisters within the cellular surface as well as crenation and 'budding' of the erythrocytes. After neuraminidase treatment, long filaments were observed to radiate from the surface of the erythrocyte. The other enzymes investigated, RNA'se DNA'se, phospholipase, protease and trypsin, produced no demonstrable effect on the cellular structure, nor (with the possible exception of trypsin) on the cell coat as seen by subsequent staining with ruthenium red. Putative calcium binding sites on and in the erythrocyte membrane were demonstrated. Following incubation with radioactive calcium, activity was found in the erythrocyte membranes. Calcium binding could be reduced by prior treatment of the erythrocyte with EDTA, neuraminidase, and to a lesser extent, by papain and trypsin. Other enzymes had no demonstrable effect. Stored erythrocytes showed a progressive diminution in calcium binding over a period of up to 4 weeks.
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PMID:Localization and role of calcium in the erythrocyte coat: effects of enzymes and storage. 72 71

Investigation of the cell S--Ig in acute lymphocytic leukaemia (ALL), at the onset of relapse of the disease, shows quite marked differences from patient to patient according to the extent of the immunofluorescent-positive cells. They may vary from 0.5 to 25% or more. When these Ig-positive cells are treated with trypsin and then incubated "in vitro" for six hours, many of them are no longer Ig-positive, i.e. they do not synthesize Ig. It might be possible, that the membrane-Ig observed before trypsinization does not represent true Ig-determinants of mature B-cells (antibodies attached to leukaemia-specific determinants?). The extent of these features decrease in remission until their disappearance. Relationship between the cell immunological patterns and the treatment response in ALL could exist. In a group of ALL-patients under the same treatment, that is, vincristine and prednisone, the correlation between the course of the disease after the above-mentioned therapy showed quick and complete remission in patients with low percentage of Ig-positive cells (below 10%) and poor improvement (often without complete remission) in patients with higher percentage of Ig-positive cells. Among the most important B-lymphocyte abnormalities in chronic lymphocytic leukaemia (CLL) are the following: (a) fluorescence intensity may vary not only from patient to patient, but also from cell to cell in the same patient; (b) the Fc-receptor can be lacking; (c) the C3b-receptor is not always present, or it is from 2 to 20-folds less frequent than the C3d-receptor, whereas normal human lymphocytes do not show any outstanding differences between the number of EAC rosette-forming cells either when tested with mouse complement (C3d-receptor) or with human complement C3b-receptor); (d) the traffic capacity of peripheral-blood B-lymphocytes in CLL is quite defective. Results of the observations on lymphocytes in CLL, taken as a whole, suggest that CLL is in general given by the expansion of an abnormal clone of cells of B origin, arrested in their maturative development, non-responsive to the mitogen stimulation, accumulating in the peripheral-blood for a traffic deficiency. On the contrary, the T-cells class is apparently normal, and the T-cell extent in CLL-peripheral blood can be even greater than normal when taken as absolute value.
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PMID:Lymphocyte immunological patterns in leukaemia: a review. 78 Feb 27

Using purified human complement components, the participation of C5 in phagocytosis was investigated. The addition of C5 to EAC 1423 increased both rosette formation and phagocytosis of the intermediates by human polymorphonuclear leukocytes. The opsonizing activity of C5b was not affected after decay of its hemolytic activity. Both C3- and C5-dependent phagocytosis is abolished either in the presence of chelating agents or by pretreatment of the polymorphonuclear leukocytes with trypsin. The enhancing effect of C5b in phagocytosis can be reduced either by further reaction with C6 and C7 or with anti-C5 F(ab)2 fragments.
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PMID:C5-dependent enhancement of rosette formation and phagocytosis by human polymorphonuclear leukocytes. 91 12

The recent interest for highly sophisticated techniques of dental tissue preparation aiming to display very particular structures, moved the AA. to improve the literature suggestions. In particular they made TEM and SEM observations of transitional zones between healthy and normal pulp and dentin after decalcification and trypsin at different concentrations treatment. The images obtained draw in the attention the study facilities of a technique that really removes all the non collagenic material. The data obtained in the pericellular zones also allowed some interventions in the recent literature discussion about inter-odontoblastic fibres.
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PMID:[An ultrastructural study of the fibrillary component of dental tissues]. 193 74

Human deciduous teeth undergoing physiologic root resorption were extracted and fixed with a mixture of formaldehyde and glutaraldehyde and processed for scanning (SEM) and transmission (TEM) electron microscopy, and for acid (ACPase) and alkaline phosphatase (ALPase) cytochemistry. The resorbant organ, rich in odontoclasts, cementoblasts, fibroblasts, and macrophages, formed prominent resorption lacunae in root dentin. SEM observations of resorption lacunae treated with trypsin solution showed islands of newly-formed cementum matrix in part of the resorbing dentin surfaces. Such cementum consisted of bundles of densely-arranged collagen fibrils and, in part, contained forming cementocytic lacunae and canaliculi. Active cementoblasts adjacent to odontoclasts on resorbing dentin surfaces showed cuboidal outlines and were characterized by the presence of numerous cisterns of rough endoplasmic reticulum, well-developed Golgi complexes, secretion granules, and many mitochondria. They sometimes formed a thin layer of cementoid and/or cementum matrix upon the resorbing dentin surface. These cementoblasts had ACPase-positive lysosomes in the cell bodies and exhibited intense ALPase activity along the plasma membranes of whole cell surfaces. These results suggest that, during root resorption, 1) active cementoblasts are present adjacent to active odontoclasts and 2) these cementoblasts are involved in remodeling the resorbing dentin surfaces.
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PMID:Possible role of cementoblasts in the resorbant organ of human deciduous teeth during root resorption. 214 74

In many experimental models of skeletal muscle damage and in human muscle disease, empty basement membrane tubes remain following the destruction of muscle fibres. In the present study we test the hypothesis that the empty basement membrane tubes play an essential role in the orientation of regenerating muscle fibres. Two groups of 15 Wistar rats were used. In one group, aqueous barium chloride (BaCl2) solution was injected into the right quadriceps muscle; in the other group, freshly prepared 2% trypsin solution was similarly injected. The different stages of muscle cell necrosis and regeneration were observed by histology, by immunofluorescence using an anti-basement membrane antibody, and by transmission (TEM) and scanning electron microscopy (SEM) in animals killed 1-77 days following injection. Although there was muscle fibre necrosis at sites of BaCl2 injection, empty basement membrane tubes were well preserved. Myoblasts grew along the empty basement membrane tubes and by 77 days, the regenerated muscle fibres at the site of the injection were well oriented. Trypsin not only destroyed muscle fibres but also destroyed the basement membrane tubes; in the early stages of regeneration the myoblasts were disorientated but by 77 days, regeneration was comparable to that seen in the barium chloride injected muscle. The results of this study suggest that preservation of empty basement membrane tubes is not essential for the orientation of regenerating myoblasts in skeletal muscle.
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PMID:Role of the basement membrane in the regeneration of skeletal muscle. 240 30


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