Mutations responsible for MYH9-related thrombocytopenia impair SDF-1-driven migration of megakaryoblastic cells

SummaryMYH9-related disease (MYH9-RD) is an autosomal-dominant thrombocytopenia caused by mutations in the gene for the heavy chain of nonmuscle myosin-IIA (NMMHC-IIA). Recent in vitro studies led to the hypothesis that thrombocytopenia of MYH9-RD derives from an ectopic platelet release by megakaryocytes in the osteoblastic areas of bone marrow (BM), which are enriched in type I collagen, rather than in vascular spaces. SDF-1-driven migration of megakaryocytes within BM to reach the vascular spaces is a key mechanism for platelet biogenesis. Since myosin-IIA is implicated in polarised migration of different cell types, we hypothesised that MYH9 mutations could interfere with this mechanism. We therefore investigated the SDF-1-driven migration of a megakaryoblastic cell line, Dami cells, on type I collagen or fibrinogen by a modified transwell assay. Inhibition of myosin-IIA ATPase activity suppressed the SDF-1-driven migration of Dami cells, while over-expression of NMMHC-IIA increased the efficiency of chemotaxis, indicat- ing a role for NMMHC-IIA in this mechanism. Transfection of cells with three MYH9 mutations frequently responsible for MYH9-RD (p.R702C, p.D1424H, or p.R1933X) resulted in a defective SDF-1-driven migration with respect to the wild-type counterpart and in increased cell spreading onto collagen. Analysis of differential localisation of wild-type and mutant proteins suggested that mutant NMMHC-IIAs had an impaired cytoplasmic re-organisation in functional cytoskeletal structures after cell adhesion to collagen. These findings support the hypothesis that a defect of SDF-1-driven migration of megakaryocytes induced by MYH9 mutations contributes to ectopic platelet release in the BM osteoblastic areas, resulting in ineffective platelet production.

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Megakaryocytes of patients with MYH9-related thrombocytopenia present an altered proplatelet formation

Thrombosis and Haemostasis ◽

10.1160/th09-01-0068 ◽

2009 ◽

Vol 102 (07) ◽

pp. 90-96 ◽

Cited By ~ 39

Author(s):

Alessandro Malara ◽

Stefania Badalucco ◽

Valeria Bozzi ◽

Mauro Torti ◽

Carlo L. Balduini ◽

...

Keyword(s):

Bone Marrow ◽

Type I Collagen ◽

Autosomal Dominant ◽

Lower Number ◽

Type I ◽

Related Disease ◽

Platelet Release ◽

Proplatelet Formation ◽

Myosin Iia

Summary MYH9-related disease (MYH9-RD) is an autosomal-dominant thrombocytopenia caused by mutations of MYH9, the gene for the heavy chain of myosin-IIA. Pathogenesis of thrombocytopenia of MYH9-RD is unknown. Recent studies in mice demonstrated that myosin-IIA is an inhibitor of proplatelet formation (PPF), and suggested that it could be involved in the suppression of PPF exerted by megakaryocyte adhesion to type I collagen, which regulates the timing of platelet release within bone marrow. However, the consequences on PPF of the heterozygous mutations causative of the MYH9-RD have never been investigated. We studied the in-vitro PPF by megakaryocytes obtained from four patients carrying the p.D1424N or the p.R1933X mutations. We demonstrated that MYH9-RD megakaryocytes completely lose the physiologic suppression of proplatelet extension exerted by interaction with type I collagen, thus supporting the hypothesis that a premature platelet release within bone marrow contributes to pathogenesis of MYH9-related thrombocytopenia. Moreover, proplatelets extended by MYH9-RD megakaryocytes presented a significant defect in branching in secondary processes (p=0.001) and formed a significantly lower number of proplatelet tips (p=0.005). Since platelets are assembled at the level of proplatelet tips, this defect could further contribute to pathogenesis of thrombocytopenia of MYH9-RD patients.

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A type I collagen reporter gene construct for protein engineering studies. Functional equivalence of transfected reporter COL1A1 and endogenous gene products during biosynthesis and in vitro extracellular matrix accumulation

Biochemical Journal ◽

10.1042/bj2930387 ◽

1993 ◽

Vol 293 (2) ◽

pp. 387-394 ◽

Cited By ~ 8

Author(s):

S R Lamandé ◽

J F Bateman

Keyword(s):

Extracellular Matrix ◽

Reporter Gene ◽

Type I Collagen ◽

Type I ◽

Wild Type ◽

Reporter Construct ◽

Reporter Protein ◽

Gene Construct ◽

Reporter Gene Construct

A type I collagen reporter gene construct, designed to facilitate detailed analysis of the consequences of introduced structural and regulatory mutations on collagen biosynthesis and participation in the extracellular matrix, was produced by site-directed mutagenesis of the mouse COL1A1 gene. The reporter construct, pWTCI-Ile822, carried a single base change which converted the codon for amino acid 822 of the triple helix from methionine to isoleucine. This change allowed the reporter protein, [Ile822]alpha 1(I), to be distinguished from the wild-type alpha 1(I), and quantified, by its altered CNBr cleavage pattern. In mouse Mov13 cells, which synthesize no endogenous pro alpha 1(I), reporter chains associated with endogenous pro alpha 2(I), formed pepsin-stable triple helices and were secreted efficiently from the cell. The thermal stability of wild-type molecules and molecules containing the reporter [Ile822]alpha 1(I) chains was identical. The biosynthetic characteristics of wild-type and reporter chains were directly compared in stably transfected 3T6 cells. These cells did not make a distinction between reporter and endogenous alpha 1(I) chains, which were secreted from the cells at the same rate and were processed and deposited into the 3T6 cell in vitro accumulated extracellular matrix with equal efficiency. These data demonstrate that the helical sequence alteration in the reporter protein is functionally neutral and that the reporter construct, pWTCI-Ile822, is a suitable vector for the analysis of the biochemical effects of site-directed mutations in the putative COL1A1 functional domains.

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Separate cis-acting DNA elements of the mouse pro-alpha 1(I) collagen promoter direct expression of reporter genes to different type I collagen-producing cells in transgenic mice.

The Journal of Cell Biology ◽

10.1083/jcb.129.5.1421 ◽

1995 ◽

Vol 129 (5) ◽

pp. 1421-1432 ◽

Cited By ~ 172

Author(s):

J Rossert ◽

H Eberspaecher ◽

B de Crombrugghe

Keyword(s):

Transgenic Mice ◽

Type I Collagen ◽

Cell Types ◽

Proximal Promoter ◽

Type I ◽

High Level Expression ◽

Cis Acting ◽

High Level ◽

Different Cell Types ◽

Beta Galactosidase

The genes coding for the two type I collagen chains, which are active selectively in osteoblasts, odontoblasts, fibroblasts, and some mesenchymal cells, constitute good models for studying the mechanisms responsible for the cell-specific activity of genes which are expressed in a small number of discrete cell types. To test whether separate genetic elements could direct the activity of the mouse pro-alpha 1(I) collagen gene to different cell types in which it is expressed, transgenic mice were generated harboring various fragments of the proximal promoter of this gene cloned upstream of the Escherichia coli beta-galactosidase gene. During embryonic development, X-gal staining allows for the precise identification of the different cell types in which the beta-galactosidase gene is active. Transgenic mice harboring 900 bp of the pro-alpha 1(I) proximal promoter expressed the transgene at relatively low levels almost exclusively in skin. In mice containing 2.3 kb of this proximal promoter, the transgene was also expressed at high levels in osteoblasts and odontoblasts, but not in other type I collagen-producing cells. Transgenic mice harboring 3.2 kb of the proximal promoter showed an additional high level expression of the transgene in tendon and fascia fibroblasts. The pattern of expression of the lacZ transgene directed by the 0.9- and 2.3-kb pro-alpha 1(I) proximal promoters was confirmed by using the firefly luciferase gene as a reporter gene. The pattern of expression of this transgene, which can be detected even when it is active at very low levels, paralleled that of the beta-galactosidase gene. These data strongly suggest a modular arrangement of separate cell-specific cis-acting elements that can activate the mouse pro-alpha(I) collagen gene in different type I collagen-producing cells. At least three different types of cell-specific elements would be located in the first 3.2 kb of the promoter: (a) an element that confers low level expression in dermal fibroblasts; (b) a second that mediates high level expression in osteoblasts and odontoblasts; and (c) one responsible for high level expression in tendon and fascia fibroblasts. Our data also imply that other cis-acting cell-specific elements which direct activity of the gene to still other type I collagen-producing cells remain to be identified.

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CEACAM1 negatively regulates platelet-collagen interactions and thrombus growth in vitro and in vivo

Blood ◽

10.1182/blood-2008-06-165043 ◽

2009 ◽

Vol 113 (8) ◽

pp. 1818-1828 ◽

Cited By ~ 57

Author(s):

Cyndi Wong ◽

Yong Liu ◽

Jana Yip ◽

Rochna Chand ◽

Janet L. Wee ◽

...

Keyword(s):

Type I Collagen ◽

Tyrosine Phosphatase ◽

Negative Regulator ◽

Surface Glycoprotein ◽

Type I ◽

Wild Type ◽

Glycoprotein Vi ◽

Selective Ligand

Abstract Carcinoembryonic antigen cell adhesion molecule-1 (CEACAM1) is a surface glycoprotein expressed on various blood cells, epithelial cells, and vascular cells. CEACAM1 possesses adhesive and signaling properties mediated by its intrinsic immunoreceptor tyrosine-based inhibitory motifs that recruit SHP-1 protein-tyrosine phosphatase. In this study, we demonstrate that CEACAM1 is expressed on the surface and in intracellular pools of platelets. In addition, CEACAM1 serves to negatively regulate signaling of platelets by collagen through the glycoprotein VI (GPVI)/Fc receptor (FcR)–γ-chain. ceacam1−/− platelets displayed enhanced type I collagen and GPVI-selective ligand, collagen-related peptide (CRP), CRP-mediated platelet aggregation, enhanced platelet adhesion on type I collagen, and elevated CRP-mediated alpha and dense granule secretion. Platelets derived from ceacam1−/− mice form larger thrombi when perfused over a collagen matrix under arterial flow compared with wild-type mice. Furthermore, using intravital microscopy to ferric chloride-injured mesenteric arterioles, we show that thrombi formed in vivo in ceacam1−/− mice were larger and were more stable than those in wild-type mice. GPVI depletion using monoclonal antibody JAQ1 treatment of ceacam1−/− mice showed a reversal in the more stable thrombus growth phenotype. ceacam1−/− mice were more susceptible to type I collagen–induced pulmonary thromboembolism than wild-type mice. Thus, CEACAM1 acts as a negative regulator of platelet-collagen interactions and of thrombus growth involving the collagen GPVI receptor in vitro and in vivo.

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The Effect of Collagen-I Coatings of 3D Printed PCL Scaffolds for Bone Replacement on Three Different Cell Types

Applied Sciences ◽

10.3390/app112211063 ◽

2021 ◽

Vol 11 (22) ◽

pp. 11063

Author(s):

Lucas Weingärtner ◽

Sergio H. Latorre ◽

Dirk Velten ◽

Anke Bernstein ◽

Hagen Schmal ◽

...

Keyword(s):

Tissue Engineering ◽

Type I Collagen ◽

Testing Machine ◽

Cell Types ◽

The Body ◽

Type I ◽

Human Tissues ◽

Cytotoxicity Studies ◽

Cell Scaffold ◽

Different Cell Types

Introduction The use of scaffolds in tissue engineering is becoming increasingly important as solutions need to be found to preserve human tissues such as bone or cartilage. Various factors, including cells, biomaterials, cell and tissue culture conditions, play a crucial role in tissue engineering. The in vivo environment of the cells exerts complex stimuli on the cells, thereby directly influencing cell behavior, including proliferation and differentiation. Therefore, to create suitable replacement or regeneration procedures for human tissues, the conditions of the cells’ natural environment should be well mimicked. Therefore, current research is trying to develop 3-dimensional scaffolds (scaffolds) that can elicit appropriate cellular responses and thus help the body regenerate or replace tissues. In this work, scaffolds were printed from the biomaterial polycaprolactone (PCL) on a 3D bioplotter. Biocompatibility testing was used to determine whether the printed scaffolds were suitable for use in tissue engineering. Material and Methods An Envisiontec 3D bioplotter was used to fabricate the scaffolds. For better cell-scaffold interaction, the printed polycaprolactone scaffolds were coated with type-I collagen. Three different cell types were then cultured on the scaffolds and various tests were used to investigate the biocompatibility of the scaffolds. Results Reproducible scaffolds could be printed from polycaprolactone. In addition, a coating process with collagen was developed, which significantly improved the cell-scaffold interaction. Biocompatibility tests showed that the PCL-collagen scaffolds are suitable for use with cells. The cells adhered to the surface of the scaffolds and as a result extensive cell growth was observed on the scaffolds. The inner part of the scaffolds, however, remained largely uninhabited. In the cytotoxicity studies, it was found that toxicity below 20% was present in some experimental runs. The determination of the compressive strength by means of the universal testing machine Z005 by ZWICK according to DIN EN ISO 604 of the scaffolds resulted in a value of 68.49 ± 0.47 MPa.

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Evolution of Attenuation and Risk of Reversal in Peste des Petits Ruminants Vaccine Strain Nigeria 75/1

Viruses ◽

10.3390/v11080724 ◽

2019 ◽

Vol 11 (8) ◽

pp. 724 ◽

Cited By ~ 5

Author(s):

Roger-junior Eloiflin ◽

Marie Boyer ◽

Olivier Kwiatek ◽

Samia Guendouz ◽

Etienne Loire ◽

...

Keyword(s):

Cell Cultures ◽

Vaccine Strain ◽

Low Frequency ◽

Cell Types ◽

Peste Des Petits Ruminants ◽

Wild Type ◽

Consensus Sequences ◽

Vaccination Campaigns ◽

Different Cell Types

Peste des Petits Ruminants (PPR) is a highly infectious disease caused by a virus of the Morbillivirus genus. The current PPR eradication effort relies mainly on the implementation of massive vaccination campaigns. One of the most widely used PPR vaccines is the Nigeria 75/1 strain obtained after attenuation by 75 serial passages of the wild type isolate in cell cultures. Here we use high throughput deep sequencing of the historical passages that led to the Nigeria 75/1 attenuated strain to understand the evolution of PPRV attenuation and to assess the risk of reversal in different cell types. Comparison of the consensus sequences of the wild type and vaccine strains showed that only 18 fixed mutations separate the two strains. At the earliest attenuation passage at our disposal (passage 47), 12 out of the 18 mutations were already present at a frequency of 100%. Low-frequency variants were identified along the genome in all passages. Sequencing of passages after the vaccine strain showed evidence of genetic drift during cell passages, especially in cells expressing the SLAM receptor targeted by PPRV. However, 15 out of the 18 mutations related to attenuation remained fixed in the population. In vitro experiments suggest that one mutation in the leader region of the PPRV genome affects virus replication. Our results suggest that only a few mutations can have a serious impact on the pathogenicity of PPRV. Risk of reversion to virulence of the attenuated PPRV strain Nigeria 75/1 during serial passages in cell cultures seems low but limiting the number of passages during vaccine production is recommended.

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Expression of Haemophilus ducreyi Collagen Binding Outer Membrane Protein NcaA Is Required for Virulence in Swine and Human Challenge Models of Chancroid

Infection and Immunity ◽

10.1128/iai.74.5.2651-2658.2006 ◽

2006 ◽

Vol 74 (5) ◽

pp. 2651-2658 ◽

Cited By ~ 25

Author(s):

Robert A. Fulcher ◽

Leah E. Cole ◽

Diane M. Janowicz ◽

Kristen L. Toffer ◽

Kate R. Fortney ◽

...

Keyword(s):

Membrane Protein ◽

Outer Membrane ◽

Outer Membrane Protein ◽

Type I Collagen ◽

Haemophilus Ducreyi ◽

Swine Model ◽

Type I ◽

Wild Type ◽

Collagen Binding

ABSTRACT Haemophilus ducreyi, the etiologic agent of the sexually transmitted genital ulcer disease chancroid, has been shown to associate with dermal collagen fibers within infected skin lesions. Here we describe NcaA, a previously uncharacterized outer membrane protein that is important for H. ducreyi collagen binding and host colonization. An H. ducreyi strain lacking the ncaA gene was impaired in adherence to type I collagen but not fibronectin (plasma or cellular form) or heparin. The mutation had no effect on serum resistance or binding to HaCaT keratinocytes or human foreskin fibroblasts in vitro. Escherichia coli expressing H. ducreyi NcaA bound to type I collagen, demonstrating that NcaA is sufficient to confer collagen attachment. The importance of NcaA in H. ducreyi pathogenesis was assessed using both swine and human experimental models of chancroid. In the swine model, 20% of lesions from sites inoculated with the ncaA mutant were culture positive for H. ducreyi 7 days after inoculation, compared to 73% of wild-type-inoculated sites. The average number of CFU recovered from mutant-inoculated lesions was also significantly reduced compared to that recovered from wild-type-inoculated sites at both 2 and 7 days after inoculation. In the human challenge model, 8 of 30 sites inoculated with wild-type H. ducreyi progressed to the pustular stage, compared to 0 of 30 sites inoculated with the ncaA mutant. Together these results demonstrate that the collagen binding protein NcaA is required for H. ducreyi infection.

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Collagen fibrillogenesis in vitro: interaction of types I and V collagen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142670 ◽

1986 ◽

Vol 44 ◽

pp. 210-211

Author(s):

Arthur J. Wasserman ◽

Kathy C. Kloos ◽

David E. Birk

Keyword(s):

Type I Collagen ◽

Corneal Stroma ◽

Minor Component ◽

Homogeneous Distribution ◽

Type I ◽

Type V Collagen ◽

Fibril Morphology ◽

Type V ◽

In Vitro Interaction

Type I collagen is the predominant collagen in the cornea with type V collagen being a quantitatively minor component. However, the content of type V collagen (10-20%) in the cornea is high when compared to other tissues containing predominantly type I collagen. The corneal stroma has a homogeneous distribution of these two collagens, however, immunochemical localization of type V collagen requires the disruption of type I collagen structure. This indicates that these collagens may be arranged as heterpolymeric fibrils. This arrangement may be responsible for the control of fibril diameter necessary for corneal transparency. The purpose of this work is to study the in vitro assembly of collagen type V and to determine whether the interactions of these collagens influence fibril morphology.

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Restoration of Osteogenesis by CRISPR/Cas9 Genome Editing of the Mutated COL1A1 Gene in Osteogenesis Imperfecta

Journal of Clinical Medicine ◽

10.3390/jcm10143141 ◽

2021 ◽

Vol 10 (14) ◽

pp. 3141

Author(s):

Hyerin Jung ◽

Yeri Alice Rim ◽

Narae Park ◽

Yoojun Nam ◽

Ji Hyeon Ju

Keyword(s):

Osteogenesis Imperfecta ◽

Type I Collagen ◽

Disease Modeling ◽

Bone Fragility ◽

Osteogenic Potential ◽

Type I ◽

Gene Correction ◽

Col1a1 Gene ◽

Collagen Formation

Osteogenesis imperfecta (OI) is a genetic disease characterized by bone fragility and repeated fractures. The bone fragility associated with OI is caused by a defect in collagen formation due to mutation of COL1A1 or COL1A2. Current strategies for treating OI are not curative. In this study, we generated induced pluripotent stem cells (iPSCs) from OI patient-derived blood cells harboring a mutation in the COL1A1 gene. Osteoblast (OB) differentiated from OI-iPSCs showed abnormally decreased levels of type I collagen and osteogenic differentiation ability. Gene correction of the COL1A1 gene using CRISPR/Cas9 recovered the decreased type I collagen expression in OBs differentiated from OI-iPSCs. The osteogenic potential of OI-iPSCs was also recovered by the gene correction. This study suggests a new possibility of treatment and in vitro disease modeling using patient-derived iPSCs and gene editing with CRISPR/Cas9.

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Effects of chitosan-collagen dressing on wound healing in vitro and in vivo assays

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800021989698 ◽

2021 ◽

Vol 19 ◽

pp. 228080002198969

Author(s):

Min-Xia Zhang ◽

Wan-Yi Zhao ◽

Qing-Qing Fang ◽

Xiao-Feng Wang ◽

Chun-Ye Chen ◽

...

Keyword(s):

Wound Healing ◽

Wound Dressing ◽

Type I Collagen ◽

Inhibition Zone ◽

Negative Control ◽

Type I ◽

Nih3t3 Cells ◽

Post Operation

The present study was designed to fabricate a new chitosan-collagen sponge (CCS) for potential wound dressing applications. CCS was fabricated by a 3.0% chitosan mixture with a 1.0% type I collagen (7:3(w/w)) through freeze-drying. Then the dressing was prepared to evaluate its properties through a series of tests. The new-made dressing demonstrated its safety toward NIH3T3 cells. Furthermore, the CCS showed the significant surround inhibition zone than empty controls inoculated by E. coli and S. aureus. Moreover, the moisture rates of CCS were increased more rapidly than the collagen and blank sponge groups. The results revealed that the CCS had the characteristics of nontoxicity, biocompatibility, good antibacterial activity, and water retention. We used a full-thickness excisional wound healing model to evaluate the in vivo efficacy of the new dressing. The results showed remarkable healing at 14th day post-operation compared with injuries treated with collagen only as a negative control in addition to chitosan only. Our results suggest that the chitosan-collagen wound dressing were identified as a new promising candidate for further wound application.

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