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)

Diabetes is associated with a hypercoagulable state. Eighty percent of patients with diabetes mellitus die due to various thrombotic vascular complications. Disorder of coagulation and fibrynolysis is associated with diabetic retinopathy and nephropathy. Angiogenesis requires degradation of vascular basement membrane prior to migration and proliferation of endothelial cells. Various serine proteases play important role in this process. The homeostatic system is also the source of endogenous inhibitors of angiogenesis. Human serum contains various factors able to induce or suppress formation of new blood vessels. The aim of the present study was to evaluate the activity of some angiogenesis inhibitors, anti-proteases, anti-thrombin III, a1 anti-trypsin and a2 anti-plasmin in sera of patients with diabetes mellitus type 1 and 2 and non-proliferative retinopathy, and to correlate this activity to total angiogenic potential of these sera, measured by mice cutaneous test. Sera of 22 persons with DM1, aged 33-70 years, 35 persons with DM2, aged 37-79 years, and 51 healthy people, aged 22-80 years (as control group) were studied. Direct serum-induced cutaneous angiogenesis test in mice (SIA) was applied. Berichrom (ade Behring) tests and immunoturbidimetric method were used for evaluation of anti-proteases activity. Angiogenic activity of DM1 patients sera was statistically lower than this parameter in DM2 patients and in control group. Levels of anti-proteases were similar in DM1, DM2 and control group, with one exception: anti-thrombin level was lower in DM2 patients' sera than this in the control group. Analysis of correlation revealed important difference in behaviour of DM1 sera, as compared to other groups. Significant negative correlation was observed between angiogenic activity and anti-thrombin, as well as anti-trypsin level of DM1 patients' sera. On the other hand, correlation analysis performed for the sera of control group revealed significant positive correlation between their angiogenic activity and anti-thrombin level. No other correlations were found.
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PMID:[Proteinases inhibitors in sera of diabetic patients with non-proliferative retinopathy]. 1563 23

Immunoconjugates are being explored as novel cancer therapies with the promise of target-specific drug delivery. The immunoconjugate, huN901-DM1, composed of the humanized monoclonal IgG1 antibody, huN901, and the maytansinoid drug, DM1, is being tested in clinical trials to treat small cell lung carcinoma (SCLC). huN901-DM1 contains an average of three to four DM1 drug molecules per huN901 antibody molecule. The drug molecules are linked to huN901 through random modification of huN901 at epsilon-amino groups of lysine residues, thus yielding a heterogeneous population of conjugate species. We studied the drug distribution profile of huN901-DM1 by electrospray time-of-flight mass spectrometry(ESI-TOFMS), which showed that one to six DM1 drug molecules were attached to an antibody molecule. Both light and heavy chains contained linked drugs. The conjugation sites in both chains were determined by peptide mapping using trypsin and Asp-N protease digestion. Trypsin digestion identified modified lysine residues, since these residues were no longer susceptible to enzymatic cleavage after conjugation with the drug. With respect to Asp-N digestion, modified peptides were identified by observing a mass increase corresponding to the modification. The two digestion methods provided consistent results, leading to the identification of 20 modified lysine residues in both light and heavy chains. Each lysine residue was only partially modified. No conjugation sites were found in complementarity determining regions (CDRs). Using structural models of human IgG1, it was found that modified lysine residues were on the surface in areas of structural flexibility and had large solvent accessibility.
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PMID:Structural characterization of the maytansinoid-monoclonal antibody immunoconjugate, huN901-DM1, by mass spectrometry. 1608 51

Myotonic dystrophy type 1 (DM1) is a neuromuscular disease caused by the expansion of a CTG repeat in the DMPK gene and characterised by progressive skeletal muscle weakness and wasting. To investigate the effects of the CTG expansion on the physiological function of the skeletal muscles, we have used a transgenic mouse model carrying the human DM1 region with 550 expanded CTG repeats. Maximal force is reduced in the skeletal muscles of 10-month-old but not in 3-month-old DM1 mice when compared to age-matched non-transgenic littermates. The progressive weakness observed in the DM1 mice is directly related to the reduced muscle mass and muscle fibre size. A significant increase in trypsin-like proteasome activity and Fbxo32 expression is also measured in the DM1 muscles indicating that an atrophic process mediated by the ubiquitin-proteasome pathway may contribute to the progressive muscle wasting and weakness in the DM1 mice.
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PMID:Progressive skeletal muscle weakness in transgenic mice expressing CTG expansions is associated with the activation of the ubiquitin-proteasome pathway. 2034 70

Pro-antibody-drug conjugate (PDC) is a hybrid structural format of immunoconjugate, where the structural complexity of pro-antibody and intrinsic heterogeneity of ADCs impose a prominent analytical challenge to the in-depth characterization of PDCs. In the present study, we successfully prepared and characterized PanP-DM1 as a model of PDCs, which is an anti-EGFR pro-antibody following conjugation with DM1 at lysine residues. The drug-to-antibody ratio (DAR) of PanP-DM1 was determined by LC-MS after deglycosylation, and verified by UV/vis spectroscopy. Following reduction or IdeS digestion, the pro-antibody fragments linked with DM1 were investigated by middle-down mass spectrometry. Furthermore, more than 20 modified lysine conjugation sites were determined by peptide mapping after trypsin digestion. Additionally, more than ten glycoforms of PanP-DM1 were also identified and quantified. In summary, critical quality attributes (CQAs) of PDCs including DAR, drug load distribution, and conjugation sites were fully characterized, which would contribute to the development of other PDCs for cancer treatment.
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PMID:In-Depth Characterization of a Pro-Antibody-Drug Conjugate by LC-MS. 2737 24