The objectives of this thesis are: a) To examine racial/ethnic differences in coronary artery calcification (CAC) and CAD, between symptomatic South Asians and Caucasians, matched for age, gender and conventional cardiovascular risk factors, b) To assess, using a meta-analysis model, the natural history of and stability of measurements of coronary artery calcium scoring (CACs) based on data collected from two large published trials: St Francis and EBEAT, c) To investigate the prevalence of coronary artery calcification in individuals with CT evidence for AVC, mitral valve calcification (MAC) or of both of them (AVC+MAC), d) To assess any potential association between premature CAD (<55 years in first-degree male relatives and <65 years in first-degree female relatives) and CAC in a large cohort of asymptomatic individuals. We found that coronary artery calcification is more extensive and diffuse in symptomatic patients of South Asian ethnic origin as compared to Caucasians, despite similar conventional risk factors for CAD. This is more evident in those >50 years of age, suggesting potential genetic or other risk factors yet to be determined. The natural history of coronary artery calcification was overtime progression in the majority of subjects, irrespective of gender. The higher variability in RCA measurements could be related to the low baseline CACs or exaggerated movement of the right side atrioventricular ring, whereas those for LCA brances are influenced by the branch allocation of the CACs. Valve calcification is not isolated but involve also and the coronary arteries. The presence of calcification in the aortic valve or combined aortic and mitral valves predicted coronary artery calcification. Additionally patients in whom both valves have become calcified tend to have severe coronary artery calcification. And finally, there is no relationship between the prevalence and extent of coronary artery calcification and the presence of family history of coronary heart disease in asymptomatic individuals with none of the conventional risk factors for atherosclerosis.

A calcificação ocorre pela formação de depósitos de cálcio em diferentes matrizes envolvendo fatores mecânicos, químicos e biológicos. Alguns compósitos, polímeros e proteínas são utilizados na formação de matrizes por promover maior eficiência no processo de mineralização. Estima-se que a fibroína da seda apresente também esta finalidade. A fibroína é uma proteína fibrosa extraída do casulo do bicho-da-seda (Bombyx mori), que pode ser processada como filme, membrana, esponja, pó, gel e aplicada em ossos e cartilagens, enxertos vasculares, reparação de nervos e córnea, como sistema de liberação de drogas, suturas, ligamentos, peles, tendões e substrato para cultura de células. Nesse trabalho houve a preparação de micropartículas de fibroína da seda através de dois procedimentos distintos, um por borrifamento em N&sup2 e outro por borrifamento em Na2HPO4 e o processo de calcificação realizado foi por imersão alternada de soluções tamponadas de cálcio e fosfato. As caracterizações realizadas foram Espectroscopia de Absorção no Infravermelho (FT-IR), Análise Termogravimétrica (TGA), Microscopia Eletrônica de Varredura (MEV), Espectroscopia de Energia Dispersiva (EDS) e Calorimetria Exploratória Diferencial (DSC). Os resultados obtidos mostraram que a calcificação das micropartículas de fibroína ocorre pelas duas metodologias empregadas. O teor de calcificação foi de aproximadamente 29% para micropartículas borrifadas em N&sup2 e de aproximadamente 80% para as micropartículas borrifadas em Na2HPO4. As micropartículas de fibroína calcificadas, não apresentaram transição térmica até a temperatura de 120°C, possibilitando a esterilização em autoclave a seco. / Calcification occurs by the formation of calcium deposits in different matrices involving mechanical factors, chemical and biological. Some composites, polymers, and proteins are used in forming matrices to promote higher efficiency in the process of mineralization. It is estimated that the silk fibroin also present for this purpose. The fibroin is a fibrous protein extracted from silkworm cocoon silkworm (Bombyx mori), which can be processed as film, membrane, sponge, powder, gel and applied in bone and cartilage, vascular grafts, nerve repair and corneal as a delivery system for drugs, sutures, ligaments, skins, tendons and substrate for cell culture. In this work was the preparation of microparticles of silk fibroin by two different procedures, sputter under N&sup2 and in other sputter Na2HPO4 and calcification process was performed by immersion of alternating buffered solutions of calcium and phosphate. The characterizations were performed Absorption Spectroscopy Infrared (FT-IR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and Differential Scanning Calorimetry (DSC). The results showed that the calcification of fibroin microparticles occurs by the two methodologies. The calcified fibroin microparticles showed no thermal transition temperature to 120°C, enabling autoclaving of the microparticles dry

by Cheng Sze Lok, Alfred. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 104-109). / Abstract also in Chinese. / DECLARATION --- p.i / ABSTRACT --- p.ii / ACKNOWLEDGEMENT --- p.vii / ABBREVIATIONS --- p.ix / LIST OF FIGURES --- p.x / LIST OF TABLES --- p.xii / TABLE OF CONTENTS --- p.xiii / Chapter CHAPTER ONE 226}0ؤ --- INTRODUCTION / Chapter 1.1 --- The Growth Plate / Chapter 1.1.1 --- "Function, Structure and Biochemistry of the Growth Plate" --- p.1 / Chapter 1.1.2 --- Extracellular Matrix of the Growth Plate Cartilage --- p.4 / Chapter 1.1.3 --- Vascular Supply to the Growth Plate --- p.9 / Chapter 1.1.4 --- Endochondral Ossification --- p.10 / Chapter 1.2 --- Growth Plate Damage and the Contemporary Reconstruction Models --- p.13 / Chapter 1.3 --- The 3-D Chondrocyte Pellet Culture --- p.15 / Chapter 1.4 --- The Study Plan --- p.16 / Chapter 1.5 --- The Objectives of the Study --- p.18 / Chapter CHAPTER TWO 一 --- METHODOLOGY / Chapter 2.1 --- Biosynthesis of Artificial Growth Plate using 3-D Chondrocyte Pellet Culture / Chapter 2.1.1 --- Isolation of Rabbit Costal Resting Chondrocytes --- p.19 / Chapter 2.1.2 --- Chondrocyte Monolayer Culture --- p.20 / Chapter 2.1.3 --- Three-dimensional Chondrocyte Pellet Culture --- p.20 / Chapter 2.1.4 --- Optimization of 3-D Chondrocyte Pellet Culture System --- p.20 / Chapter 2.2 --- Characterization of the 3-D Chondrocyte Pellet Culture and Monolayer Culture / Chapter 2.2.1 --- Histomorphology --- p.22 / Chapter 2.2.2 --- Alkaline Phosphatase Histochemistry --- p.22 / Chapter 2.2.3 --- Collagen Typing --- p.23 / Chapter 2.2.3.1 --- Labeling and extraction of newly synthesized collagen / Chapter 2.2.3.2 --- SDS-PAGE and autoradiography / Chapter 2.2.4 --- Growth Rate --- p.25 / Chapter 2.2.4.1 --- Total DNA content determination / Chapter 2.2.4.2 --- Thymidine incorporation assay / Chapter 2.3 --- Implantation of Artificial Growth Plate and Assessment / Chapter 2.3.1 --- Implantation of Artificial Growth Plate into Partial Growth Plate Defect Model --- p.27 / Chapter 2.3.1.1 --- Animals / Chapter 2.3.1.2 --- Surgical procedure / Chapter 2.3.1.3 --- Experimental groups / Chapter 2.3.2 --- Histology --- p.30 / Chapter 2.3.3 --- Metabolism of Artificial Growth Plate In Vivo --- p.31 / Chapter 2.3.3.1 --- Radio sulfate labeling / Chapter 2.3.3.2 --- Liquid emulsion and autoradiography / Chapter CHAPTER THREE 一 --- RESULTS / Chapter 3.1 --- Biosynthesis of Artificial Growth Plate using 3-D Chondrocyte Pellet Culture / Chapter 3.1.1 --- Morphology of the Isolated Rabbit Chondrocyte --- p.32 / Chapter 3.1.2 --- Three-dimensional Chondrocyte Pellet Culture --- p.32 / Chapter 3.1.3 --- Optimization of 3-D Chondrocyte Pellet Culture System --- p.35 / Chapter 3.2 --- Characterization of the 3-D Chondrocyte Pellet Culture and Monolayer Culture / Chapter 3.2.1 --- Histomorphology --- p.38 / Chapter 3.2.2 --- Alkaline Phosphatase Histochemistry --- p.43 / Chapter 3.2.3 --- Collagen Typing --- p.47 / Chapter 3.2.4 --- Growth Rate --- p.50 / Chapter 3.2.4.1 --- Total DNA content determination / Chapter 3.2.4.2 --- Thymidine incorporation assay / Chapter 3.3 --- Implantation of Artificial Growth Plate and Assessment / Chapter 3.3.1 --- Histology --- p.54 / Chapter 3.3.2 --- Metabolism of Artificial Growth Plate In Vivo --- p.65 / Chapter CHAPTER FOUR 一 --- DISCUSSION / Chapter 4.1 --- Optimal Condition for 3-D Chondrocyte Pellet Culture System --- p.67 / Chapter 4.1.1 --- Some Critical Characteristics of the Growth Plate --- p.68 / Chapter 4.1.2 --- Selection of Animal Model --- p.69 / Chapter 4.1.3 --- Optimization of Culturing Conditions 226}0ؤ Screening Based on Morphological Studies --- p.69 / Chapter 4.2 --- Characterization of the 3-D Chondrocyte Pellet Culture and Monolayer Culture --- p.73 / Chapter 4.2.1 --- Development of the 3-D Chondrocyte Pellet Culture --- p.73 / Chapter 4.2.2 --- Development of the Chondrocyte Monolayer Culture --- p.78 / Chapter 4.2.3 --- Comparing the 3-D Chondrocyte Pellet Culture and Monolayer Culture --- p.79 / Chapter 4.2.3.1 --- Cellular organization / Chapter 4.2.3.2 --- Terminal differentiation of chondrocytes / Chapter 4.2.3.3 --- Cell division potential / Chapter 4.2.3.4 --- Production of cartilaginous matrix / Chapter 4.3 --- Resumption of Physeal Characteristics by Artificial Growth Plate In Vivo --- p.86 / Chapter 4.3.1 --- Three Stages of In Vivo Development of the Artificial Growth Plate --- p.86 / Chapter 4.3.1.1 --- Incorporation of artificial growth plate with host tissues / Chapter 4.3.1.2 --- Growth of the artificial growth plate invivo / Chapter 4.3.1.3 --- Resumption of endochondral ossification in the artificial growth plate / Chapter 4.3.2 --- Significance of Development of the 3-D Pellet Culture on its In Vivo Development --- p.89 / Chapter 4.3.2.1 --- 3-D pellet culture processes similar extracellular matrix with host / Chapter 4.3.2.2 --- 3-D pellet culture acquires growth plate-like cellular organization and differentiation pattern / Chapter 4.3.3 --- Effect of Host Microenvironment on Artificial Growth Plate Development --- p.90 / Chapter 4.3.3.1 --- Orientation of artificial growth plate implants / Chapter 4.3.3.2 --- Evidence from development of 3-D pellet culture in longer period of culture / Chapter 4.4 --- Comparison with other Growth Plate Reconstruction Models --- p.93 / Chapter 4.4.1 --- Implantation of Biologic or Inert Fillers --- p.93 / Chapter 4.4.2 --- Physeal Transplantation --- p.94 / Chapter 4.4.3 --- Transplantation of Cartilage Allografts --- p.95 / Chapter 4.4.4 --- Transplantation of High-density Chondrocyte Culture --- p.96 / Chapter CHAPTER FIVE 一 --- SUMMARY AND CONCLUSION --- p.98 / Chapter CHAPTER SIX 一 --- FURTHER STUDIES --- p.102 / REFERENCES --- p.104

Vascular calcification is strongly correlated with the clinical manifestations of atherosclerosis, heart attacks and strokes. The calcification process resembles bone formation and involves the osteogenic trans-differentiation of smooth muscles cells within the arterial wall. Cannabinoid receptors are known to modulate bone formation and are present in atherosclerotic vessels, suggesting they may also play a role in modulating calcification. Therefore, we evaluated the effects of cannabinoids on the expression of osteogenic proteins by vascular smooth muscle cells undergoing calcification.

archives@tulane.edu / Background Ankle brachial index (ABI) is a noninvasive measure of subclinical cardiovascular disease (CVD) and atherosclerosis of the lower extremities. Low and high levels of ABI are associated with cardiovascular mortality and vascular calcification in dialysis chronic kidney disease (CKD) patients. However, the association of the spectrum of vascular calcification with low and high ABI is not well studied in pre-dialysis CKD patients. The purpose of this study is to investigate the association of both low and high ABI with the risk of vascular calcification in CKD patients. Methods We recruited 243 patients with pre-dialysis CKD from the great New Orleans area between 2010 and 2012. Our study used a cross-sectional design with ABI and CAC measured at the same visit. Continuous ABI measurements were taken and further classified into four categories : <=0.9 (low ABI) >0.9-<1.0 (borderline), 1.0-<1.4 (normal), >=1.4 (high). Level of vascular calcification were considered as the outcome and calculated by agatston score. Three categories of CAC is defined as: CAC agaston score=0, 0-100, >100. Three cumulative logit models were applied to the data. The first is an unadjusted univariate model, the second adjusts for baseline demographics, and the third adjusts for baseline demographics and covariates that are associated with CAC. Logistic regression methods were used to calculate the odds ratio of having a higher CAC score for CKD patients. Results We found a significant association between ABI and vascular calcification. All three models returned consistently significant result (p=0.0005, 0.0005, 0.0037, respectively) for the association between ABI and CAC. In addition, low ABI (ABI≤0.9) is also associated with an increased risk of CAC and severe CAC (OR=6.183, 95%CI(1.085, 35.228)). High ABI (>1.4) is also associated with an increase in CAC and severe CAC (OR=5.064, 95%CI (1.696, 15.122)). Borderline ABI (0.9<ABI<1.0) is not associated with an increase in CAC or severe CAC (OR=2.704, 95% CI (0.702, 10.418). Conclusion Compared to normal ABI level, low and high ABIs are both significantly associated with an increased risk of coronary artery calcification and severe coronary artery calcification in CKD patients. / 1 / Shuo Bai

L'influence d'un revêtement de type RGD sur du Ticp sur l'adhésion, l'étalement et la minéralisation des ostéoblastes a été étudié. Ce revêtement accélérait la vitesse de minéralisation et augmentait la surface des zones de minéralisation. Des CNTs fonctionnalisés ont été utilisés pour induire la calcification dans le but de mimer in vitro la minéralisation des fibres de collagène dans le tissu osseux. Après 14 jours d'incubation dans un liquide biosynthétique, les CNTs fonctionnalisés ont induit la formation de calcosphérites, similaires à ceux formés dans le woven bone. Ce modèle de calcification in vitro biomimétique, mis au point sur des polymères dans notre laboratoire, a permis d'étudier l'incorporation du Sr2+ dans le minéral osseux et sa désorption. Sr2+ a été incorporé dans le minéral lors de la calcification sans induire de changement des paramètres du cristal ou de la cristallinité quelque soit la concentration initiale en Sr2+. La désorption du Sr2+ a été rapide initialement avec libération de 20 à 25 % en 16 jours, puis plus lente pour atteindre 30 % après 61 jours. Enfin, les observations en cytodynamique ont permis de voir les premières étapes d'adhésion cellulaire et de colonisation du β-TCP. Les séquences vidéo réalisées sur 8 jours de culture, ont permis d'observer la prolifération des ostéoblastes (SaOs-2) qui sembla se produire en direction des particules de β-TCP pour venir en contact direct avec les particules. Les macrophages (J774-2 et macrophages péritonéaux de souris) ne proliféraient pas mais venaient au contact direct des particules pour les dégrader. Les observations MEB ont permis de constater que les cellules émettaient des prolongements cytoplasmiques et s'étiraient pour venir se fixer et ensuite s'étaler à la surface du biomatériau. Les données obtenues grâce aux observations faites avec la vidéomicroscopie sur long terme nous ont permis de confirmer la cytocompatibilité et la biodégradabilité du β-TCP.

Heart valve structures open and close during the cardiac cycle to provide unidirectional blood flow through the heart, critical for efficient cardiovascular function. Valve dysfunction results in either incomplete opening or incomplete closure of the valve. Both types of valve dysfunction decrease efficiency of blood flow, increasing the load on the myocardium and leading to secondary heart disease such as pathological hypertrophy and heart failure. There are currently no effective treatments to prevent or slow the progression of valve disease, and there are no pharmacological treatments for advanced valve disease. Although most valve disease is associated with aging, increasing evidence suggests that valve disease often has origins in development. Congenital valvuloseptal defects affect many newborns, ranging from life-threatening malformations requiring immediate repair to more subtle, often undiagnosed defects that increase susceptibility to valve disease later in life. Therefore, an improved understanding of the mechanisms of heart valve formation and maintenance of adult valves may serve as an important step in improving valve disease treatment options. In this work, the mechanisms of normal valve development and the role of Sox9 in developing and mature valves are further studied. The temporal and spatial expression of extracellular matrix genes and proteins are examined throughout normal murine valve development. Sox9 function in the processes of valve development and valve maintenance is examined using mouse models of conditional Sox9 loss-of-function. Heart valve phenotypes in mice with reduced Sox9 function are examined throughout development and in adult mice with resultant calcific valve disease. The possible causative mechanisms of calcific valve disease in mice with reduced Sox9 function are further investigated by identification of novel possible targets of Sox9 transcriptional regulation. Together these studies improve our understanding of heart valve development, characterize a model of heart valve calcification with genetic etiology, and identify and characterize novel targets of Sox9.

Human activities have contributed to the increase in atmospheric greenhouse gases such as carbon dioxide (CO2). This anthropogenic gas emission has led to a rise in the average Earth temperature. Moreover, the ocean constitutes the major sink for anthropogenic CO2 and its dissolution in surface waters has already resulted in an increase of seawater acidity since the beginning of the industrial revolution. This is commonly called ocean acidification. The increase in water temperature could induce modifications of the physical and chemical characteristics of the ocean. Also, the structure and the functioning of marine ecosystems may be altered as a result of ocean acidification. Phytoplankton productivity is one of the primary controls in regulating our climate, for instance via impact on atmospheric CO2 levels. Coccolithophores, of which Emiliania huxleyi is the most abundant species, are considered to be the most important pelagic calcifying organisms on Earth. Coccolithophores are characterized by calcium carbonate platelets (coccoliths) covering the exterior of the cells. They form massive blooms in temperate and sub-polar oceans and in particular along continental margin and in shelf seas. The intrinsic coupling of organic matter production and calcification in coccolithophores underlines their biogeochemical importance in the marine carbon cycle. Both processes are susceptible to change with ocean acidification and warming. Coccolithophores are further known to produce transparent exopolymer particles (TEP) that promote particle aggregation and related processes such as marine snow formation and sinking. Thus, the impact of ocean warming and acidification on coccolithophores needs to be studied and this can be carried out through a transdisciplinary approach. The first part of this thesis consisted of laboratory experiments on E. huxleyi under controlled conditions. The aim was to estimate the effect of increasing water temperature and acidity on E. huxleyi and especially on the calcification. Cultures were conducted at different partial pressures of CO2 (pCO2); the values considered were 180, 380 and 750 ppm corresponding to past, present and future (year 2100) atmospheric pCO2. These experiments were conducted at 13°C and 18°C. The cellular calcite concentration decreases with increasing pCO2. In addition, it decreases by 34 % at 380 ppm and by 7 % at 750 ppm with an increase in temperature of 5°C. Changes in calcite production at future pCO2 values are reflected in deteriorated coccolith morphology, while temperature does not affect coccolith morphology. Our findings suggest that the sole future increase of pCO2 may have a larger negative impact on calcification than its interacting effect with temperature or the increase in temperature alone. The evolution of culture experiments allows a better comprehension of the development of a bloom in natural environments. Indeed, in order to predict the future evolution of calcifying organisms, it is required to better understand the present-day biogeochemistry and ecology of pelagic calcifying communities under field conditions. The second part of this dissertation was dedicated to results obtained during field investigations in the northern Bay of Biscay, where frequent and recurrent coccolithophorid blooms were observed. Cruises, assisted by remote sensing, were carried out along the continental margin in 2006 (29 May – 10 June), 2007 (7 May – 24 May) and 2008 (5 May – 23 May). Relevant biogeochemical parameters were measured in the water column (temperature, salinity, dissolved oxygen, Chlorophyll-a and nutrient concentrations) in order to determine the status of the bloom at the time of the different campaigns. Calcification has been shown to be extremely important in the study area. In addition, TEP production was significant at some stations, suggesting that the northern Bay of Biscay could constitute an area of important carbon export. Mortality factors for coccolithophores were studied and the first results of lysis rates measured in this region were presented. Results obtained during culture experiments and comparison with data reported in the literature help to better understand and to predict the future of coccolithophores in a context of climate change. Data obtained during either culture experiments or field investigations allowed a better understanding of the TEP dynamics. Finally, the high lysis rates obtained demonstrate the importance of this process in bloom decline. Nevertheless, it is clear that we only begin to understand the effects of global change on marine biogeochemistry, carbon cycling and potential feedbacks on increasing atmospheric CO2. Thus, further research with a combination of laboratory experiments, field measurements and modelling are encouraged.

The effect of Ddr1 deletion on the expression of genes involved in atherosclerotic vascular remodeling and on the development of atherosclerotic calcification Pamela J. Ahmad, PhD Institute of Medical Science, 2008 During atherosclerosis, collagen molecules, which are abundant in the healthy vessel, are extensively degraded, re-synthesized or newly synthesized, and remodeled to induce profound changes in VSMCs as they colonize and expand atherosclerotic lesions. The central theme of this thesis was to investigate the effect of genetic deletion of a collagen receptor, DDR1, on VSMC processes during atherosclerosis. In the first study, we demonstrated a role for DDR1 as an important regulator of gene expression in synthetic VSMCs. We have profiled the expression of vascular collagen matrix molecules, MMPs and TIMPs in synthetic VSMCs and we have demonstrated that deletion of Ddr1 is sufficient to accelerate ECM remodeling in synthetic VSMCs, which may influence cell migration during atherosclerosis. Moreover, we have extended our knowledge of DDR1 function in synthetic VSMCs, by demonstrating that DDR1 limits VSMC proliferation in a complex matrix microenvironment representative of the ECM produced in the vessel wall during vascular disease. In the second study, we investigated the role of DDR1 in atherosclerotic calcification, a feature of advanced atherosclerotic disease. Here, we demonstrated that intimal calcification in Ldlr-/- mice fed a high-fat/ high-cholesterol diet may be mediated through the initiation of a chondrogenic transcriptional regulatory program and that deletion of Ddr1 significantly attenuated the frequency and extent of atherosclerotic mineralization in vivo, as well as the ability of vascular smooth muscle cells to calcify in vitro, suggesting an important role for DDR1 in VSMCs as a positive regulator of this pathological process. In our third study, we provided evidence of a biochemical association between MMP-2 and DDR1b in VSMCs, which involves a direct interaction between MMP-2 and the extracellular region of the DDR1 receptor. In addition, we reported an association between endogenous MMP-2 and Stat1 in VSMCs, providing a platform for future research to investigate the functional consequences of these novel interactions.

The effect of Ddr1 deletion on the expression of genes involved in atherosclerotic vascular remodeling and on the development of atherosclerotic calcification Pamela J. Ahmad, PhD Institute of Medical Science, 2008 During atherosclerosis, collagen molecules, which are abundant in the healthy vessel, are extensively degraded, re-synthesized or newly synthesized, and remodeled to induce profound changes in VSMCs as they colonize and expand atherosclerotic lesions. The central theme of this thesis was to investigate the effect of genetic deletion of a collagen receptor, DDR1, on VSMC processes during atherosclerosis. In the first study, we demonstrated a role for DDR1 as an important regulator of gene expression in synthetic VSMCs. We have profiled the expression of vascular collagen matrix molecules, MMPs and TIMPs in synthetic VSMCs and we have demonstrated that deletion of Ddr1 is sufficient to accelerate ECM remodeling in synthetic VSMCs, which may influence cell migration during atherosclerosis. Moreover, we have extended our knowledge of DDR1 function in synthetic VSMCs, by demonstrating that DDR1 limits VSMC proliferation in a complex matrix microenvironment representative of the ECM produced in the vessel wall during vascular disease. In the second study, we investigated the role of DDR1 in atherosclerotic calcification, a feature of advanced atherosclerotic disease. Here, we demonstrated that intimal calcification in Ldlr-/- mice fed a high-fat/ high-cholesterol diet may be mediated through the initiation of a chondrogenic transcriptional regulatory program and that deletion of Ddr1 significantly attenuated the frequency and extent of atherosclerotic mineralization in vivo, as well as the ability of vascular smooth muscle cells to calcify in vitro, suggesting an important role for DDR1 in VSMCs as a positive regulator of this pathological process. In our third study, we provided evidence of a biochemical association between MMP-2 and DDR1b in VSMCs, which involves a direct interaction between MMP-2 and the extracellular region of the DDR1 receptor. In addition, we reported an association between endogenous MMP-2 and Stat1 in VSMCs, providing a platform for future research to investigate the functional consequences of these novel interactions.