scholarly journals Collagen Structure-Function Mapping Informs Applications for Regenerative Medicine

2020 ◽  
Vol 8 (1) ◽  
pp. 3
Author(s):  
James D. San Antonio ◽  
Olena Jacenko ◽  
Andrzej Fertala ◽  
Joseph P.R.O. Orgel

Type I collagen, the predominant protein of vertebrates, assembles into fibrils that orchestrate the form and function of bone, tendon, skin, and other tissues. Collagen plays roles in hemostasis, wound healing, angiogenesis, and biomineralization, and its dysfunction contributes to fibrosis, atherosclerosis, cancer metastasis, and brittle bone disease. To elucidate the type I collagen structure-function relationship, we constructed a type I collagen fibril interactome, including its functional sites and disease-associated mutations. When projected onto an X-ray diffraction model of the native collagen microfibril, data revealed a matrix interaction domain that assumes structural roles including collagen assembly, crosslinking, proteoglycan (PG) binding, and mineralization, and the cell interaction domain supporting dynamic aspects of collagen biology such as hemostasis, tissue remodeling, and cell adhesion. Our type III collagen interactome corroborates this model. We propose that in quiescent tissues, the fibril projects a structural face; however, tissue injury releases blood into the collagenous stroma, triggering exposure of the fibrils’ cell and ligand binding sites crucial for tissue remodeling and regeneration. Applications of our research include discovery of anti-fibrotic antibodies and elucidating their interactions with collagen, and using insights from our angiogenesis studies and collagen structure-function model to inform the design of super-angiogenic collagens and collagen mimetics.

2020 ◽  
Vol 115 (11) ◽  
pp. 399-408
Author(s):  
Catherine Maidment ◽  
Meekyung Ahn ◽  
Rafea Naffa ◽  
Trevor Loo ◽  
Gillian Norris

Looseness is a defect found in leather that reduces its quality by causing a wrinkly appearance in the finished product, resulting in a reduction in its value. Earlier studies on loose leather using microscopy and Raman spectroscopy reported a change in the collagen structure of loose leather. In this study, proteomics was used to investigate the possible molecular causes of looseness in the raw material, the first time such a study has been carried out. Proteins extracted from two regions of raw hide using two different methods were analysed; those taken from the distal axilla, an area prone to looseness, and those taken from the backbone which is less prone to looseness. Analyses using 1DE-LC-MS/MS showed that although the overall collagen concentration was similar in both areas of the hide, the distribution of the different types of collagen differed.  Specifically, concentrations of type I collagen, and the collagen-associated proteoglycan decorin were lower in samples taken from the distal axilla, symptomatic of a collagen network with excess space seen for these samples using confocal microscopy. This study suggests a possible link between the molecular components of raw cattle hide and looseness and more importantly between the molecular components of skin and skin defects. There is therefore potential to develop biomarkers for looseness which will enable early preventative action.


1984 ◽  
Vol 62 (6) ◽  
pp. 462-469 ◽  
Author(s):  
Hardy Limeback ◽  
Kichibee Otsuka ◽  
Kam-Ling Yao ◽  
Jane E. Aubin ◽  
Jaro Sodek

A number of bone cell clones isolated from rat calvaria have been maintained in culture for more than 3 years. Several of these clones have undergone dramatic changes in phenotype. One of these clones, RGB 2.2, was observed originally to have a fibroblastic morphology in culture and to respond to parathyroid hormone (PTH), but not prostaglandin E2 (PGE2), with an increase in intracellular cAMP. Throughout several passages in early subcultures, these cells synthesized mostly type I collagen, with small amounts of type III and type V collagens. Whereas PTH had no detectable effect on collagen synthesis, PGE2 decreased the amount of total cell layer collagen, with the greatest effect on type III collagen, while increasing the proportion of type V collagen. Subsequent studies on these cells during 3 years in culture have indicated changes in their phenotype including a progressive change in morphology to a more cuboidal shape and a change in collagen synthesis, the cells producing large amounts of the "embryonic" collagen, α1(I) trimer. The reason(s) for the change in collagen expression is unknown, but may be the result of a change in which gene(s) is being expressed.


Author(s):  
Lucas Félix ROSSI ◽  
Manoel Roberto Maciel TRINDADE ◽  
Armando José D`ACAMPORA ◽  
Luise MEURER

ABSTRACT Background: Hernia correction is a routinely performed treatment in surgical practice. The improvement of the operative technique and available materials certainly has been a great benefit to the quality of surgical results. The insertion of prostheses for hernia correction is well-founded in the literature, and has become the standard of treatment when this type of disease is discussed. Aim: To evaluate two available prostheses: the polypropylene and polypropylene coated ones in an experimental model. Methods: Seven prostheses of each kind were inserted into Wistar rats (Ratus norvegicus albinus) in the anterior abdominal wall of the animal in direct contact with the viscera. After 90 days follow-up were analyzed the intra-abdominal adhesions, and also performed immunohistochemical evaluation and videomorphometry of the total, type I and type III collagen. Histological analysis was also performed with hematoxylin-eosin to evaluate cell types present in each mesh. Results: At 90 days the adhesions were not different among the groups (p=0.335). Total collagen likewise was not statistically different (p=0.810). Statistically there was more type III collagen in the coated polypropylene group (p=0.039) while type I was not different among the prostheses (p=0.050). The lymphocytes were statistically more present in the polypropylene group (p=0.041). Conclusion: The coated prosthesis was not different from the polypropylene one regarding the adhesion. Total and type I collagen were not different among the groups, while type III collagen was more present on the coated mesh. There was a greater number of lymphocytes on the polypropylene mesh.


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Louie C. Alexander ◽  
Grant McHorse ◽  
Janet L. Huebner ◽  
Anne-Christine Bay-Jensen ◽  
Morten A. Karsdal ◽  
...  

Abstract Objective To compare C-reactive protein (CRP) and matrix metalloproteinase-generated neoepitope of CRP (CRPM) as biomarkers of inflammation and radiographic severity in patients with knee osteoarthritis. Methods Participants with symptomatic osteoarthritis (n=25) of at least one knee underwent knee radiographic imaging and radionuclide etarfolatide imaging to quantify inflammation of the knees and other appendicular joints. For purposes of statistical analysis, semi-quantitative etarfolatide and radiographic imaging scores were summed across the knees; etarfolatide scores were also summed across all joints to provide a multi-joint synovitis measure. Multiple inflammation and collagen-related biomarkers were measured by ELISA including CRP, CRPM, MMP-generated neoepitopes of type I collagen and type III collagen in serum (n=25), and CD163 in serum (n=25) and synovial fluid (n=18). Results BMI was associated with CRP (p=0.001), but not CRPM (p=0.753). Adjusting for BMI, CRP was associated with radiographic knee osteophyte score (p=0.002), while CRPM was associated with synovitis of the knee (p=0.017), synovitis of multiple joints (p=0.008), and macrophage marker CD163 in serum (p=0.009) and synovial fluid (p=0.03). CRP correlated with MMP-generated neoepitope of type I collagen in serum (p=0.045), and CRPM correlated with MMP-generated neoepitope of type III collagen in serum (p<0.0001). No biomarkers correlated with age, knee pain, or WOMAC pain. Conclusions To our knowledge, this is the first time that CRPM has been shown to be associated with knee and multi-joint inflammation based on objective imaging (etarfolatide) and biomarker (CD163) measures. These results demonstrate the capability of biomarker measurements to reflect complex biological processes and for neoepitope markers to more distinctly reflect acute processes than their precursor proteins. CRPM is a promising biomarker of local and systemic inflammation in knee OA that is associated with cartilage degradation and is independent of BMI. CRPM is a potential molecular biomarker alternative to etarfolatide imaging for quantitative assessment of joint inflammation.


1990 ◽  
Vol 265 (2) ◽  
pp. 461-469 ◽  
Author(s):  
A H Ang ◽  
G Tachas ◽  
J H Campbell ◽  
J F Bateman ◽  
G R Campbell

Enzymically isolated rabbit aortic smooth-muscle cells (SMC) in the first few days of primary culture express a ‘contractile phenotype’, but with time these cells modulate to a ‘synthetic phenotype’. Synthetic-state SMC are able to proliferate, and, provided that they undergo fewer than 5 cumulative population doublings, return to the contractile phenotype after reaching confluency [Campbell, Kocher, Skalli, Gabbiani & Campbell (1989) Arteriosclerosis 9, 633-643]. The present study has determined the synthesis of collagen, at the protein and mRNA levels, by cultured SMC as they undergo a change in phenotypic state. The results show that, upon modulating to the synthetic phenotype, SMC synthesized 25-30 times more collagen than did contractile cells. At the same time, non-collagen-protein synthesis increased only 5-6-fold, indicating a specific stimulation of collagen synthesis. Steady-state mRNA levels are also elevated, with alpha 2(I) and alpha 1(III) mRNA levels 30 times and 20 times higher respectively, probably reflecting increased transcriptional activity. Phenotypic modulation was also associated with an alteration in the relative proportions of type I and III collagens synthesized, contractile SMC synthesizing 78.1 +/- 3.6% (mean +/- S.D.) type I collagen and 17.5 +/- 4.7% type III collagen, and synthetic cells synthesizing 90.3 +/- 2.0% type I collagen and 5.8% +/- 1.8% type III collagen. Enrichment of type I collagen was similarly noted at the mRNA level. On return to the contractile state, at confluency, collagen production and the percentage of type I collagen decreased. This further illustrates the close association between the phenotypic state of SMC and their collagen-biosynthetic phenotype.


2006 ◽  
Vol 290 (1) ◽  
pp. H323-H330 ◽  
Author(s):  
Jennifer E. Naugle ◽  
Erik R. Olson ◽  
Xiaojin Zhang ◽  
Sharon E. Mase ◽  
Charles F. Pilati ◽  
...  

Cardiac fibroblast (CF) proliferation and differentiation into hypersecretory myofibroblasts can lead to excessive extracellular matrix (ECM) production and cardiac fibrosis. In turn, the ECM produced can potentially activate CFs via distinct feedback mechanisms. To assess how specific ECM components influence CF activation, isolated CFs were plated on specific collagen substrates (type I, III, and VI collagens) before functional assays were carried out. The type VI collagen substrate potently induced myofibroblast differentiation but had little effect on CF proliferation. Conversely, the type I and III collagen substrates did not affect differentiation but caused significant induction of proliferation (type I, 240.7 ± 10.3%, and type III, 271.7 ± 21.8% of basal). Type I collagen activated ERK1/2, whereas type III collagen did not. Treatment of CFs with angiotensin II, a potent mitogen of CFs, enhanced the growth observed on types I and III collagen but not on the type VI collagen substrate. Using an in vivo model of myocardial infarction (MI), we measured changes in type VI collagen expression and myofibroblast differentiation after post-MI remodeling. Concurrent elevations in type VI collagen and myofibroblast content were evident in the infarcted myocardium 20-wk post-MI. Overall, types I and III collagen stimulate CF proliferation, whereas type VI collagen plays a potentially novel role in cardiac remodeling through facilitation of myofibroblast differentiation.


Development ◽  
1980 ◽  
Vol 60 (1) ◽  
pp. 245-254
Author(s):  
G. B. Shellswell ◽  
A. J. Bailey ◽  
V. C. Duance ◽  
D. J. Restall

We have used antibodies to three of the isomorphic forms of collagen, types I, III and V, in an immunofluorescence microscopy study of myogenesis in the embryonic chick wing, concentrating on the period between stages 27 and 30 (5 to 7·5 days incubation) which is when the dorsal and ventral muscle masses separate into discrete muscles. We have demonstrated the presence of all three collagen types at the ectoderm-mesenchyme junction from stage 27 onwards. Type I collagen and then type III collagen are found in progressively deeper layers of the dermis at the later stages. Both types I and V collagen are initially present in the cartilage elements, but type 1 collagen becomes restricted to the periphery of these structures at later stages. The developing muscle areas show a lack of staining at all stages and it is only at the latest stages that types I and III collagen first appear in the surrounding epimysium. We discuss possible mechanisms for the division of the muscle masses in the light of this information on the distribution of collagen types.


2020 ◽  
pp. 019459982097825
Author(s):  
Kastley Marvin ◽  
Isaac Schwartz ◽  
Edward Utz ◽  
Justin Wilson ◽  
Christopher Johnson ◽  
...  

Objective The objective of this study was to investigate the effects of fractional CO2 laser on subglottic scar. Study Design Randomized controlled animal study. Setting Academic medical center. Methods Subglottic scar was induced in 12 New Zealand white rabbits via an endoscopic brush technique. This was followed by an open airway surgery that included vertical division of the cricoid and proximal trachea. Eight rabbits underwent fractional CO2 laser treatment of the scar via a Lumenis Ultrapulse Deep FX handpiece. Four rabbits underwent the open surgical approach without laser treatment. Bronchoscopy was performed at weeks 1, 2, 4, and 8. The animals were euthanized and laryngotracheal complexes harvested 12 weeks postsurgery. Immunohistochemistry was performed to determine the collagen composition of treated and untreated scars. Results All 12 subjects survived to the study endpoint with no significant respiratory complications, despite 10 of 12 developing some degree of lateral tracheal narrowing. The median ratio of type I collagen to type III collagen in the laser group (1.57) was significantly more favorable than that of the untreated group (2.84; P = .03). Conclusion Treatment with fractional CO2 laser appears to have similar effects on subglottic scars as with cutaneous scars, improving the ratio of type I to type III collagen. Additionally, we developed an open airway approach in the rabbit model to deliver fractional CO2 laser treatment to the subglottis without introducing respiratory complications or compromising survival.


1977 ◽  
Author(s):  
L. Balleisen ◽  
R. Timpl ◽  
S. Gay

The reaction of platelets with fibrillar collagen was measured by recording aggregation according to Borns method and by retraction of Ancrod-fibrin clots. These reactions could be completely inhibited by coating the fibrils with stoichiometric amounts of purified antibodies to type I, II or III collagens. The inhibition was specific, i. e. antibodies to type I collagen prevented aggregation by type I collagen but not by type II or III collagen. Comparable amounts ofantibodies to fibrinogen or to serum albumin had no effect on the reaction. The data indicate that platelet aggregation by type I or II collagen fibrils is not due to contamination with type III collagen. The inhibition reaction may be useful for further studies on molecular parameters of the interaction between platelets and collagen fibers.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Zhenjie Huang ◽  
Peng Wei ◽  
Luoman Gan ◽  
Tonghua Zeng ◽  
Caicheng Qin ◽  
...  

Objective. This study aims to explore the role of erythromycin-regulated histone deacetylase-2 in benign tracheal stenosis. Methods. The rabbit model of tracheal stenosis was established. The rabbits were randomly divided into 8 groups. Histone deacetylase-2 (HDAC2) expression was detected by immunofluorescence. The expression of type I collagen and type III collagen was detected by immunohistochemical method. The expression of TGF-β1, VEGF and IL-8 in serum and alveolar lavage fluid was detected by ELISA. The expression of HDAC2, TGF-β1, VEGF and IL-8 in bronchi of each group was detected by Western blotting method. Results. In Erythromycin (ERY) group, ERY + Budesonide group, ERY + Vorinostat group and ERY + Budesonide + Vorinostat group, the degree of bronchial stenosis was alleviated, and the mucosal epithelium was still slightly proliferated. The effect of ERY combined with other drugs was more obvious. The HDAC2 protein expression increased significantly in ERY group, ERY + Budesonide group and ERY + Budesonide + Vorinostat group and decreased significantly in Vorinostat group, the expression of collagen I and III decreased significantly in ERY group, ERY + Budesonide group and ERY + Budesonide + Vorinostat group (P<0.05). The TGF-β1, IL-8 and VEGF levels decreased significantly in ERY group, ERY + Budesonide group, ERY + Vorinostat group and ERY + Budesonide + Vorinostat group (P<0.05). Conclusions. Erythromycin inhibited inflammation and excessive proliferation of granulation tissue after tracheobronchial mucosal injury by up-regulating the expression of HDAC2, it promoted wound healing and alleviated tracheobronchial stenosis. When combined with budesonide, penicillin and other glucocorticoids and antibiotics, it had a good synergistic effect. However, vorinostat could attenuate erythromycin’s effect by down-regulating the expression of HDAC2. It may have good clinical application prospects in the treatment of tracheal stenosis.


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