Leptospira interrogans enters different host cells by binding to distinct molecules in the extracellular matrix

Many types of polymer nanofibers have been introduced as artificial extracellular matrices. Their controllable properties, such as wettability, surface charge, transparency, elasticity, porosity and surface to volume proportion, have attracted much attention. Moreover, functionalizing polymers with other bioactive components could enable the engineering of microenvironments to host cells for regenerative medical applications. In the current brief review, we focus on the most recently cited electrospun nanofibrous polymeric scaffolds and divide them into five main categories: natural polymer-natural polymer composite, natural polymer-synthetic polymer composite, synthetic polymer-synthetic polymer composite, crosslinked polymers and reinforced polymers with inorganic materials. Then, we focus on their physiochemical, biological and mechanical features and discussed the capability and efficiency of the nanofibrous scaffolds to function as the extracellular matrix to support cellular function.

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A decellularized human corneal scaffold for anterior corneal surface reconstruction

Scientific Reports ◽

10.1038/s41598-021-82678-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Naresh Polisetti ◽

Anke Schmid ◽

Ursula Schlötzer-Schrehardt ◽

Philip Maier ◽

Stefan J. Lang ◽

...

Keyword(s):

Extracellular Matrix ◽

Ex Vivo ◽

Sodium Deoxycholate ◽

Nuclear Material ◽

Biological Properties ◽

Host Cells ◽

Human Cornea ◽

Human Donor ◽

Short Period

AbstractAllogenic transplants of the cornea are prone to rejection, especially in repetitive transplantation and in scarred or highly vascularized recipient sites. Patients with these ailments would particularly benefit from the possibility to use non-immunogenic decellularized tissue scaffolds for transplantation, which may be repopulated by host cells in situ or in vitro. So, the aim of this study was to develop a fast and efficient decellularization method for creating a human corneal extracellular matrix scaffold suitable for repopulation with human cells from the corneal limbus. To decellularize human donor corneas, sodium deoxycholate, deoxyribonuclease I, and dextran were assessed to remove cells and nuclei and to control tissue swelling, respectively. We evaluated the decellularization effects on the ultrastructure, optical, mechanical, and biological properties of the human cornea. Scaffold recellularization was studied using primary human limbal epithelial cells, stromal cells, and melanocytes in vitro and a lamellar transplantation approach ex vivo. Our data strongly suggest that this approach allowed the effective removal of cellular and nuclear material in a very short period of time while preserving extracellular matrix proteins, glycosaminoglycans, tissue structure, and optical transmission properties. In vitro recellularization demonstrated good biocompatibility of the decellularized human cornea and ex vivo transplantation revealed complete epithelialization and stromal repopulation from the host tissue. Thus, the generated decellularized human corneal scaffold could be a promising biological material for anterior corneal reconstruction in the treatment of corneal defects.

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Cathepsin L in COVID-19: From Pharmacological Evidences to Genetics

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.589505 ◽

2020 ◽

Vol 10 ◽

Author(s):

Caio P. Gomes ◽

Danilo E. Fernandes ◽

Fernanda Casimiro ◽

Gustavo F. da Mata ◽

Michelle T. Passos ◽

...

Keyword(s):

Extracellular Matrix ◽

Antigen Processing ◽

Cathepsin L ◽

Modern Science ◽

Immunological Response ◽

Multiple Organ ◽

Bone Diseases ◽

Host Cells ◽

Matrix Remodeling ◽

Inflammatory Status

The coronavirus disease 2019 (COVID-19) pandemics is a challenge without precedent for the modern science. Acute Respiratory Discomfort Syndrome (ARDS) is the most common immunopathological event in SARS-CoV-2, SARS-CoV, and MERS-CoV infections. Fast lung deterioration results of cytokine storm determined by a robust immunological response leading to ARDS and multiple organ failure. Here, we show cysteine protease Cathepsin L (CatL) involvement with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and COVID-19 from different points of view. CatL is a lysosomal enzyme that participates in numerous physiological processes, including apoptosis, antigen processing, and extracellular matrix remodeling. CatL is implicated in pathological conditions like invasion and metastasis of tumors, inflammatory status, atherosclerosis, renal disease, diabetes, bone diseases, viral infection, and other diseases. CatL expression is up-regulated during chronic inflammation and is involved in degrading extracellular matrix, an important process for SARS-CoV-2 to enter host cells. In addition, CatL is probably involved in processing SARS-CoV-2 spike protein. As its inhibition is detrimental to SARS-CoV-2 infection and possibly exit from cells during late stages of infection, CatL could have been considered a valuable therapeutic target. Therefore, we describe here some drugs already in the market with potential CatL inhibiting capacity that could be used to treat COVID-19 patients. In addition, we discuss the possible role of host genetics in the etiology and spreading of the disease.

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Binding of Brucella protein, Bp26, to select extracellular matrix molecules

BMC Molecular and Cell Biology ◽

10.1186/s12860-019-0239-7 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 4

Author(s):

Yasmin ElTahir ◽

Amna Al-Araimi ◽

Remya R. Nair ◽

Kaija J. Autio ◽

Hongmin Tu ◽

...

Keyword(s):

Extracellular Matrix ◽

Type I Collagen ◽

Host Cells ◽

Mouse Serum ◽

Enzyme Linked Immunosorbent Assay ◽

Target Cells ◽

Type I ◽

Dependent Manner ◽

Biolayer Interferometry

Abstract Background Brucella is a facultative intracellular pathogen responsible for zoonotic disease brucellosis. Little is known about the molecular basis of Brucella adherence to host cells. In the present study, the possible role of Bp26 protein as an adhesin was explored. The ability of Brucella protein Bp26 to bind to extracellular matrix (ECM) proteins was determined by enzyme-linked immunosorbent assay (ELISA) and biolayer interferometry (BLI). Results ELISA experiments showed that Bp26 bound in a dose-dependent manner to both immobilized type I collagen and vitronectin. Bp26 bound weakly to soluble fibronectin but did not bind to immobilized fibronectin. No binding to laminin was detected. Biolayer interferometry showed high binding affinity of Bp26 to immobilized type I collagen and no binding to fibronectin or laminin. Mapping of Bp26 antigenic epitopes by biotinylated overlapping peptides spanning the entire sequence of Bp26 using anti Bp26 mouse serum led to the identification of five linear epitopes. Collagen and vitronectin bound to peptides from several regions of Bp26, with many of the binding sites for the ligands overlapping. The strongest binding for anti-Bp26 mouse serum, collagen and vitronectin was to the peptides at the C-terminus of Bp26. Fibronectin did not bind to any of the peptides, although it bound to the whole Bp26 protein. Conclusions Our results highlight the possible role of Bp26 protein in the adhesion process of Brucella to host cells through ECM components. This study revealed that Bp26 binds to both immobilized and soluble type I collagen and vitronectin. It also binds to soluble but not immobilized fibronectin. However, Bp26 does not bind to laminin. These are novel findings that offer insight into understanding the interplay between Brucella and host target cells, which may aid in future identification of a new target for diagnosis and/or vaccine development and prevention of brucellosis.

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Calcium-Induced Virulence Factors Associated with the Extracellular Matrix of Mucoid Pseudomonas aeruginosa Biofilms

Journal of Bacteriology ◽

10.1128/jb.187.13.4327-4337.2005 ◽

2005 ◽

Vol 187 (13) ◽

pp. 4327-4337 ◽

Cited By ~ 121

Author(s):

S. Sarkisova ◽

M. A. Patrauchan ◽

D. Berglund ◽

D. E. Nivens ◽

M. J. Franklin

Keyword(s):

Gene Expression ◽

Extracellular Matrix ◽

Pseudomonas Aeruginosa ◽

Host Cells ◽

Matrix Composition ◽

Confocal Laser ◽

Extracellular Proteases ◽

Pulmonary Tissue ◽

Bacterial Gene ◽

Calcium Addition

ABSTRACT Pseudomonas aeruginosa colonizes the pulmonary tissue of patients with cystic fibrosis (CF), leading to biofilm-associated infections. The pulmonary fluid of CF patients usually contains elevated concentrations of cations and may contain the P. aeruginosa redox-active pigment pyocyanin, which is known to disrupt calcium homeostasis of host cells. Since divalent cations are important bridging ions for bacterial polysaccharides and since they may play regulatory roles in bacterial gene expression, we investigated the effect of calcium ions on the extracellular matrix constituents of P. aeruginosa biofilms. For mucoid strain P. aeruginosa FRD1, calcium addition (1.0 and 10 mM as CaCl2) resulted in biofilms that were at least 10-fold thicker than biofilms without added calcium. Scanning confocal laser microscopy showed increased spacing between cells for the thick biofilms, and Fourier transform infrared spectroscopy revealed that the material between cells is primarily alginate. An algD transcriptional reporter demonstrated that calcium addition caused an eightfold increase in alg gene expression in FRD1 biofilms. Calcium addition also resulted in increased amounts of three extracellular proteases (AprA, LasB, and PrpL). Immunoblots of the biofilm extracellular material established that AprA was harbored within the biofilm extracellular matrix. An aprA deletion mutation and a mutation in gene for a putative P. aeruginosa calmodulin-like protein did not significantly affect calcium-induced biofilm structure. Two-dimensional gel electrophoresis showed increased amounts of phenazine biosynthetic proteins in FRD1 biofilms and in calcium-amended planktonic cultures. Spectrochemical analyses showed that the calcium addition causes a three- to fivefold increase in pyocyanin production. These results demonstrate that calcium addition affects the structure and extracellular matrix composition of mucoid P. aeruginosa biofilms, through increased expression and stability of bacterial extracellular products. The calcium-induced extracellular matrix of mucoid P. aeruginosa consists primarily of the virulence factor alginate and also harbors extracellular proteases and perhaps pyocyanin, a biomolecule that may further disrupt cellular calcium levels.

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Structure and function of accessory Sec proteins involved in the adhesin export pathway of Streptococcus gordonii

10.1101/219105 ◽

2017 ◽

Author(s):

Yu Chen ◽

Barbara A. Bensing ◽

Ravin Seepersaud ◽

Wei Mi ◽

Maofu Liao ◽

...

Keyword(s):

Extracellular Matrix ◽

Pathogenic Bacteria ◽

Structure And Function ◽

Host Cells ◽

Carbohydrate Binding ◽

Streptococcus Gordonii ◽

Carbohydrate Binding Proteins ◽

Sec Proteins ◽

And Function ◽

Complex Crystal

ABSTRACTMany pathogenic bacteria, including Streptococcus gordonii, possess a pathway for the export of a single serine-rich-repeat protein that mediates the adhesion of bacteria to host cells and the extracellular matrix. These adhesins are O-glycosylated by several cytosolic glycosyltransferases and require three accessory Sec proteins (Asp1-3) for export, but how the adhesins are processed for secretion is not well defined. Here, we show that O-glycosylation of S. gordonii adhesin GspB occurs in a sequential manner by three enzymes (GtfA/B, Nss, Gly) that attach N-acetylglucosamine and glucose to Ser/Thr residues. The modified substrate is subsequently transferred from the last glycosyltransferase to the Asp1/2/3 complex. Crystal structures show that both Asp1 and Asp3 are related to carbohydrate binding proteins. Asp1 also has an affinity for phospholipids, which is attenuated by Asp2. These results suggest a mechanism for the modification of adhesin in the cytosol and its subsequent targeting to the export machinery.

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A Decellularized Human Corneal Scaffold for Anterior Corneal Surface Reconstruction

10.21203/rs.3.rs-109219/v1 ◽

2020 ◽

Author(s):

Naresh Polisetti ◽

Anke Schmid ◽

Ursula Schlötzer-Schrehardt ◽

Philip Maier ◽

Stefan Lang ◽

...

Keyword(s):

Extracellular Matrix ◽

Ex Vivo ◽

Sodium Deoxycholate ◽

Nuclear Material ◽

Biological Properties ◽

Host Cells ◽

Human Cornea ◽

Human Donor ◽

Short Period

Abstract Allogenic transplants of the cornea are prone to rejection, especially in repetitive transplantation and in scarred or highly vascularized recipient sites. Patients with these ailments would particularly benefit from the possibility to use non-immunogenic decellularized tissue scaffolds for transplantation, which may be repopulated by host cells in situ or in vitro. So, the aim of this study was to develop a fast and efficient decellularization method for creating a human corneal extracellular matrix scaffold suitable for repopulation with human cells from the corneal limbus. To decellularize human donor corneas, sodium deoxycholate, deoxyribonuclease I, and dextran were assessed to remove cells and nuclei and to control tissue swelling, respectively. We evaluated the decellularization effects on the ultrastructure, optical, mechanical, and biological properties of the human cornea. Scaffold recellularization was studied using primary human limbal epithelial cells, stromal cells, and melanocytes in vitro and a lamellar transplantation approach ex vivo. Our data strongly suggest that this approach allowed the effective removal of cellular and nuclear material in a very short period of time while preserving extracellular matrix proteins, glycosaminoglycans, tissue structure, and optical transmission properties. In vitro recellularization demonstrated good biocompatibility of the decellularized human cornea and ex vivo transplantation revealed complete epithelialization and stromal repopulation from the host tissue. Thus, the generated decellularized human corneal scaffold could be a promising biological material for anterior corneal reconstruction in the treatment of corneal defects.

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Clumps of Mesenchymal Stem Cell/Extracellular Matrix Complexes Generated with Xeno-Free Conditions Facilitate Bone Regeneration via Direct and Indirect Osteogenesis

International Journal of Molecular Sciences ◽

10.3390/ijms20163970 ◽

2019 ◽

Vol 20 (16) ◽

pp. 3970 ◽

Cited By ~ 5

Author(s):

Souta Motoike ◽

Mikihito Kajiya ◽

Nao Komatsu ◽

Susumu Horikoshi ◽

Tomoya Ogawa ◽

...

Keyword(s):

Extracellular Matrix ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Bone Regeneration ◽

Three Dimensional ◽

Host Cells ◽

Dependent Manner ◽

Serum Free ◽

Serum Free Conditions ◽

Free Serum

Three-dimensional clumps of mesenchymal stem cell (MSC)/extracellular matrix (ECM) complexes (C-MSCs) consist of cells and self-produced ECM. We demonstrated previously that C-MSCs can be transplanted into bone defect regions with no artificial scaffold to induce bone regeneration. To apply C-MSCs in a clinical setting as a reliable bone regenerative therapy, the present study aimed to generate C-MSCs in xeno-free/serum-free conditions that can exert successful bone regenerative properties and to monitor interactions between grafted cells and host cells during bone healing processes. Human bone marrow-derived MSCs were cultured in xeno-free/serum-free medium. To obtain C-MSCs, confluent cells that had formed on the cellular sheet were scratched using a micropipette tip and then torn off. The sheet was rolled to make a round clump of cells. Then, C-MSCs were transplanted into an immunodeficient mouse calvarial defect model. Transplantation of C-MSCs induced bone regeneration in a time-dependent manner. Immunofluorescence staining showed that both donor human cells and host mice cells contributed to bone reconstruction. Decellularized C-MSCs implantation failed to induce bone regeneration, even though the host mice cells can infiltrate into the defect area. These findings suggested that C-MSCs generated in xeno-free/serum-free conditions can induce bone regeneration via direct and indirect osteogenesis.

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In vivo engineered extracellular matrix scaffolds with instructive niches for oriented tissue regeneration

Nature Communications ◽

10.1038/s41467-019-12545-3 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 31

Author(s):

Meifeng Zhu ◽

Wen Li ◽

Xianhao Dong ◽

Xingyu Yuan ◽

Adam C. Midgley ◽

...

Keyword(s):

Extracellular Matrix ◽

Tissue Regeneration ◽

Spatial Organization ◽

Cultured Cells ◽

Functional Integration ◽

Host Cells ◽

Hierarchical Porous ◽

Parallel Microchannels

Abstract Implanted scaffolds with inductive niches can facilitate the recruitment and differentiation of host cells, thereby enhancing endogenous tissue regeneration. Extracellular matrix (ECM) scaffolds derived from cultured cells or natural tissues exhibit superior biocompatibility and trigger favourable immune responses. However, the lack of hierarchical porous structure fails to provide cells with guidance cues for directional migration and spatial organization, and consequently limit the morpho-functional integration for oriented tissues. Here, we engineer ECM scaffolds with parallel microchannels (ECM-C) by subcutaneous implantation of sacrificial templates, followed by template removal and decellularization. The advantages of such ECM-C scaffolds are evidenced by close regulation of in vitro cell activities, and enhanced cell infiltration and vascularization upon in vivo implantation. We demonstrate the versatility and flexibility of these scaffolds by regenerating vascularized and innervated neo-muscle, vascularized neo-nerve and pulsatile neo-artery with functional integration. This strategy has potential to yield inducible biomaterials with applications across tissue engineering and regenerative medicine.

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Targeting the Tumor Microenvironment for Cancer Therapy

Clinical Chemistry ◽

10.1373/clinchem.2012.185363 ◽

2013 ◽

Vol 59 (1) ◽

pp. 85-93 ◽

Cited By ~ 191

Author(s):

Nor Eddine Sounni ◽

Agnès Noel

Keyword(s):

Extracellular Matrix ◽

Tumor Microenvironment ◽

Cancer Cells ◽

Cancer Progression ◽

Local Environment ◽

Tumor Stroma ◽

Host Cells ◽

Stromal Compartment ◽

Tumor Infiltrate ◽

Cellular Components

BACKGROUND With the emergence of the tumor microenvironment as an essential ingredient of cancer malignancy, therapies targeting the host compartment of tumors have begun to be designed and applied in the clinic. CONTENT The malignant features of cancer cells cannot be manifested without an important interplay between cancer cells and their local environment. The tumor infiltrate composed of immune cells, angiogenic vascular cells, lymphatic endothelial cells, and cancer-associated fibroblastic cells contributes actively to cancer progression. The ability to change these surroundings is an important property by which tumor cells are able to acquire some of the hallmark functions necessary for tumor growth and metastatic dissemination. Thus in the clinical setting the targeting of the tumor microenvironment to encapsulate or destroy cancer cells in their local environment has become mandatory. The variety of stromal cells, the complexity of the molecular components of the tumor stroma, and the similarity with normal tissue present huge challenges for therapies targeting the tumor microenvironment. These issues and their interplay are addressed in this review. After a decade of intensive clinical trials targeting cellular components of the tumor microenvironment, more recent investigations have shed light on the important role in cancer progression played by the noncellular stromal compartment composed of the extracellular matrix. SUMMARY A better understanding of how the tumor environment affects cancer progression should provide new targets for the isolation and destruction of cancer cells via interference with the complex crosstalk established between cancer cells, host cells, and their surrounding extracellular matrix.

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