Jason L. Dragoo

Bio: Jason L. Dragoo is an academic researcher from University of Colorado Denver. The author has contributed to research in topics: Anterior cruciate ligament & Platelet-rich plasma. The author has an hindex of 41, co-authored 141 publications receiving 7016 citations. Previous affiliations of Jason L. Dragoo include Stanford University & University of California, Los Angeles.

Comparison of Multi-Lineage Cells from Human Adipose Tissue and Bone Marrow

Abstract: Our laboratory has recently characterized a population of cells from adipose tissue, termed processed lipoaspirate (PLA) cells, which have multi-lineage potential similar to bone-marrow-derived mesenchymal stem cells (MSCs). This study is the first comparison of PLA cells and MSCs isolated from the same patient. No significant differences were observed for yield of adherent stromal cells, growth kinetics, cell senescence, multi-lineage differentiation capacity, and gene transduction efficiency. Adipose tissue is an abundant and easily procured source of PLA cells, which have a potential like MSCs for use in tissue-engineering applications and as gene delivery vehicles.

Comparison of Growth Factor and Platelet Concentration From Commercial Platelet-Rich Plasma Separation Systems

Abstract: Background: Clinical studies claim that platelet-rich plasma (PRP) shortens recovery times because of its high concentration of growth factors that may enhance the tissue repair process. Most of these studies obtained PRP using different separation systems, and few analyzed the content of the PRP used as treatment.Purpose: This study characterized the composition of single-donor PRP produced by 3 commercially available PRP separation systems.Study Design: Controlled laboratory study.Methods: Five healthy humans donated 100 mL of blood, which was processed to produce PRP using 3 PRP concentration systems (MTF Cascade, Arteriocyte Magellan, Biomet GPS III). Platelet, white blood cell (WBC), red blood cell, and fibrinogen concentrations were analyzed by automated systems in a clinical laboratory, whereas ELISA determined the concentrations of platelet-derived growth factor αβ and ββ (PDGF-αβ, PDGF-ββ), transforming growth factor β1 (TGF-β1), and vascular endothelial growth factor (VEGF).Results: There was no...

Tissue-engineered cartilage and bone using stem cells from human infrapatellar fat pads.

Abstract: Multipotential processed lipoaspirate (PLA) cells extracted from five human infrapatellar fat pads and embedded into fibrin glue nodules, were induced into the chondrogenic phenotype using chondrogenic media. The remaining cells were placed in osteogenic media and were transfected with an adenovirus carrying the cDNA for bone morphogenetic protein-2 (BMP-2). We evaluated the tissue-engineered cartilage and bone using in vitro techniques and by placing cells into the hind legs of five severe combined immunodeficient mice. After six weeks, radiological and histological analysis indicated that the PLA cells induced into the chondrogenic phenotype had the histological appearance of hyaline cartilage. Cells transfected with the BMP-2 gene media produced abundant bone, which was beginning to establish a marrow cavity. Tissue-engineered cartilage and bone from infrapatellar fat pads may prove to be useful for the treatment of osteochondral defects.

Platelet-Rich Plasma as a Treatment for Patellar Tendinopathy A Double-Blind, Randomized Controlled Trial

Abstract: Background:Previous studies have shown improvement in patellar tendinopathy symptoms after platelet-rich plasma (PRP) injections, but no randomized controlled trial has compared PRP with dry needling (DN) for this condition.Purpose:To compare clinical outcomes in patellar tendinopathy after a single ultrasound-guided, leukocyte-rich PRP injection versus DN.Study Design:Randomized controlled trial; Level of evidence, 1.Methods:A total of 23 patients with patellar tendinopathy on examination and MRI who had failed nonoperative treatment were enrolled and randomized to receive ultrasound-guided DN alone (DN group; n = 13) or with injection of leukocyte-rich PRP (PRP group; n = 10), along with standardized eccentric exercises. Patients and the physician providing follow-up care were blinded. Participants completed patient-reported outcome surveys before and at 3, 6, 9, 12, and ≥26 weeks after treatment during follow-up visits. The primary outcome measure was the Victorian Institute of Sports Assessment (VISA)...

Human Adipose Tissue Is a Source of Multipotent Stem Cells

Abstract: Much of the work conducted on adult stem cells has focused on mesenchymal stem cells (MSCs) found within the bone marrow stroma. Adipose tissue, like bone marrow, is derived from the embryonic mesenchyme and contains a stroma that is easily isolated. Preliminary studies have recently identified a putative stem cell population within the adipose stromal compartment. This cell population, termed processed lipoaspirate (PLA) cells, can be isolated from human lipoaspirates and, like MSCs, differentiate toward the osteogenic, adipogenic, myogenic, and chondrogenic lineages. To confirm whether adipose tissue contains stem cells, the PLA population and multiple clonal isolates were analyzed using several molecular and biochemical approaches. PLA cells expressed multiple CD marker antigens similar to those observed on MSCs. Mesodermal lineage induction of PLA cells and clones resulted in the expression of multiple lineage-specific genes and proteins. Furthermore, biochemical analysis also confirmed lineage-specific activity. In addition to mesodermal capacity, PLA cells and clones differentiated into putative neurogenic cells, exhibiting a neuronal-like morphology and expressing several proteins consistent with the neuronal phenotype. Finally, PLA cells exhibited unique characteristics distinct from those seen in MSCs, including differences in CD marker profile and gene expression.

Secretion of Angiogenic and Antiapoptotic Factors by Human Adipose Stromal Cells

Abstract: Background— The delivery of autologous cells to increase angiogenesis is emerging as a treatment option for patients with cardiovascular disease but may be limited by the accessibility of sufficient cell numbers. The beneficial effects of delivered cells appear to be related to their pluripotency and ability to secrete growth factors. We examined nonadipocyte stromal cells from human subcutaneous fat as a novel source of therapeutic cells. Methods and Results— Adipose stromal cells (ASCs) were isolated from human subcutaneous adipose tissue and characterized by flow cytometry. ASCs secreted 1203±254 pg of vascular endothelial growth factor (VEGF) per 106 cells, 12 280±2944 pg of hepatocyte growth factor per 106 cells, and 1247±346 pg of transforming growth factor-β per 106 cells. When ASCs were cultured in hypoxic conditions, VEGF secretion increased 5-fold to 5980±1066 pg/106 cells (P=0.0016). The secretion of VEGF could also be augmented 200-fold by transfection of ASCs with a plasmid encoding VEGF (P<0...

Biomedical Applications of Biodegradable Polymers

Abstract: Utilization of polymers as biomaterials has greatly impacted the advancement of modern medicine. Specifically, polymeric biomaterials that are biodegradable provide the significant advantage of being able to be broken down and removed after they have served their function. Applications are wide ranging with degradable polymers being used clinically as surgical sutures and implants. In order to fit functional demand, materials with desired physical, chemical, biological, biomechanical and degradation properties must be selected. Fortunately, a wide range of natural and synthetic degradable polymers has been investigated for biomedical applications with novel materials constantly being developed to meet new challenges. This review summarizes the most recent advances in the field over the past 4 years, specifically highlighting new and interesting discoveries in tissue engineering and drug delivery applications.

Comparison of human stem cells derived from various mesenchymal tissues: Superiority of synovium as a cell source

Abstract: Objective To compare the properties of human mesenchymal stem cells (MSCs) isolated from bone marrow, synovium, periosteum, skeletal muscle, and adipose tissue. Methods Human mesenchymal tissues were obtained from 8 donors during knee surgery for ligament injury. After collagenase digestion or gradient-density separation, nucleated cells were plated at an appropriate density for expansion at the maximum rate without colony-to-colony contact. Yield, expandability, differentiation potential, and epitope profile were compared among MSCs from the 5 different tissue sources. Results Colony number per 103 nucleated cells was lower, and cell number per colony was higher, in bone marrow than in other mesenchymal tissues. When the cells were replated at low density every 14 days, bone marrow–, synovium-, and periosteum-derived cells retained their proliferation ability even at passage 10. In chondrogenesis studies in which the cells were pelleted and cultured in vitro, pellets from bone marrow–, synovium-, and periosteum-derived cells were shown to be larger and stained more extensively for cartilage matrix. Synovium-derived cells, in particular, had the greatest ability for chondrogenesis. In adipogenesis experiments, the frequency of oil red O–positive colonies was highest in synovium- and adipose tissue–derived cells. In studies of osteogenesis, the rate of alizarin red–positive colonies was highest in bone marrow–, synovium-, and periosteum-derived cells. For epitope profiling, 15 surface antigens were measured. Most appeared to have similar epitope profiles irrespective of cell source. Conclusion Our findings indicate that there are significant differences in MSC properties according to tissue source, beyond donor and experimental variation. Superiority of synovium as a potential source of MSCs for clinical applications was demonstrated.