Purification, identification, and characterization of elastase on erythrocyte membrane as factor IX-activating enzyme

Iwata, Hiroki; Kaibara, Makoto; Dohmae, Naoshi; Takio, Koji; Himeno, Ryutaro; Kawakami, S.

doi:10.1016/j.bbrc.2004.02.020

Cited by 34 publications

(39 citation statements)

References 23 publications

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“…These cleavage sites have been also reported by others (10,38,64,67). The less-complete cleavage by crude neutrophil granule extract compared to purified neutrophil proteases could be due to the presence of neutrophil-derived protease inhibitors (80).…”

Section: Discussionsupporting

confidence: 88%

Distinct Defensin Profiles inNeisseria gonorrhoeaeandChlamydia trachomatisUrethritis Reveal Novel Epithelial Cell-Neutrophil Interactions

et al. 2005

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Defensins are key participants in mucosal innate defense. The varied antimicrobial activity and differential distribution of defensins at mucosal sites indicate that peptide repertoires are tailored to site-specific innate defense requirements. Nonetheless, few studies have investigated changes in peptide profiles and function after in vivo pathogen challenge. Here, we determined defensin profiles in urethral secretions of healthy men and men with Chlamydia trachomatis-and Neisseria gonorrhoeae-mediated urethritis by immunoblotting for the epithelial defensins HBD1, HBD2, and HD5 and the neutrophil defensins HNP1 to -3 (HNP1-3). HBD1 was not detectable in secretions, and HBD2 was only induced in a small proportion of the urethritis patients; however, HD5 and HNP1-3 were increased in C. trachomatis infection and significantly elevated in N. gonorrhoeae infection. When HNP1-3 levels were low, HD5 appeared mostly as the propeptide; however, when HNP1-3 levels were >10 g/ml, HD5 was proteolytically processed, suggesting neutrophil proteases might contribute to HD5 processing. HD5 and HNP1-3 were bactericidal against C. trachomatis and N. gonorrhoeae, but HD5 activity was dependent upon N-terminal processing of the peptide. In vitro proteolysis of proHD5 by neutrophil proteases and analysis of urethral secretions by surface-enhanced laser desorption ionization substantiated that neutrophils contribute the key convertases for proHD5 in the urethra during these infections. This contrasts with the small intestine, where Paneth cells secrete both proHD5 and its processing enzyme, trypsin. In conclusion, we describe a unique defensin expression repertoire in response to inflammatory sexually transmitted infections and a novel host defense mechanism wherein epithelial cells collaborate with neutrophils to establish an antimicrobial barrier during infection.

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Section: Discussionsupporting

confidence: 88%

Distinct Defensin Profiles inNeisseria gonorrhoeaeandChlamydia trachomatisUrethritis Reveal Novel Epithelial Cell-Neutrophil Interactions

et al. 2005

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“…4, lines 3 and 4). This result may be expected from the result obtained by SDS-PAGE analysis which showed that an incubation of F-IX with EE-IX produced F-IXee with almost the same molecular weight as that of F-IXa, but further incubation produced fragments of F-IX with lower molecular masses [13].…”

Section: Procoagulant Ability Of F-ix Cleaved By the Enzymesupporting

confidence: 52%

“…To demonstrate clearly that F-IX is activated by an enzyme on RBC membranes and the activated F-IX has procoagulant activity, it was attempted to purify, identify, and characterize the F-IX-activating enzyme in human RBC membranes [13].…”

Section: Identification Of F-ix-activating Enzyme In Rbc Membranementioning

confidence: 99%

“…As EE-IX in RBC membrane is almost in accord with neutrophil elastase, to use a synthetic fluorogenic substrate [Suc(OMe)-Ala-Ala-Pro-Val-MCA], specific for elastase, is useful for evaluating the enzymatic activity of RBCs [13,14,45]. The fluorescence intensity of a mixture of RBCs and fluorogenic substrate was measured using a photo microscope with epifluorescent optics and a fluorescence spectroscopy at kex = 380 nm and kem = 460 nm.…”

Section: Evaluation Of Enzymatic Activity Of Rbcs By Fluorescence Meamentioning

confidence: 99%

“…However, clinical evidence to support the view that markedly reduced venous flow directly induces the initiation of thrombus formation at an intact vessel wall remains contradictory [9,10]. In our previous papers [11][12][13][14], it was shown that the coagulation reaction initiated through a direct activation of F-IX by an enzyme on RBC membranes serves as a triggering mechanism for pathogenesis of venous thrombosis.…”

Section: Introductionmentioning

confidence: 99%

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Rheological study on coagulation of blood with special reference to the triggering mechanism of venous thrombus formation

Kaibara

2009

J Biorheol

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A markedly reduced blood flow, an elevation of hematocrit and an increased aggregability of erythrocytes [red blood cells (RBCs)] are risk factors for venous thrombus formation (intravascular blood coagulation). However, these risk factors alone seem to be insufficient to stimulate the coagulation cascade in the absence of a primary triggering mechanism. In this paper, our rheological and biochemical studies on blood coagulation, especially focusing on procoagulant activity of RBCs, are summarized. It is shown that the intrinsic coagulation pathway is triggered by the activation of factor IX (F-IX) by RBCs. The F-IX-activating enzyme in normal human erythrocyte (RBC) membranes was purified, identified and characterized. The activation of F-IX by RBCs was enhanced by a decrease in flow shear rate and an elevation in hematocrit. The procoagulant ability of RBCs and coagulation of blood obtained from individuals with a relatively high level of hypercoagulability were enhanced compared with those for normals. The studies demonstrated a new triggering mechanism for coagulation or thrombus formation that may occur under stagnant flow conditions.

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Bone Microenvironment

Jing¹,

Chen²

2022

Biomaterials Effect on the Bone Microenvironment

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Purification, identification, and characterization of elastase on erythrocyte membrane as factor IX-activating enzyme

Cited by 34 publications

References 23 publications

Distinct Defensin Profiles inNeisseria gonorrhoeaeandChlamydia trachomatisUrethritis Reveal Novel Epithelial Cell-Neutrophil Interactions

Distinct Defensin Profiles inNeisseria gonorrhoeaeandChlamydia trachomatisUrethritis Reveal Novel Epithelial Cell-Neutrophil Interactions

Rheological study on coagulation of blood with special reference to the triggering mechanism of venous thrombus formation

Bone Microenvironment

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