Extracellular matrix and fibroblast injection produces pterygium-like lesion in rabbits

BACKGROUND: Translational research to develop pharmaceutical and surgical treatments for pterygium requires a reliable and easy to produce animal model. Extracellular matrix and fibroblast are important components of pterygium. The aim of this study was to analyze the effect of the subconjunctival injection of fibroblast cells (NIH3T3 cell line) and exogenous extracellular matrix in rabbits in producing a pterygium-like lesion. METHODS: Six 3-month-old white New Zealand rabbits were injected with 20,000 NIH3T3 cells and 5 µL of Matrigel in the right conjunctiva, and with only 5 µL of Matrigel in the left conjunctiva. The eyes were photographed under a magnification of 16× using a 12-megapixel digital camera attached to the microscope on day 1,3 and 7. Conjunctival vascularization was measured by analyzing images to measure red pixel saturation. Area of corneal and conjunctival fibrovascular tissue formation on the site of injection was assessed by analyzing the images on day 3 and 7 using area measurement software. Histopathologic characteristics were determined in the rabbit tissues and compared with a human primary pterygium. RESULTS: The two treatments promoted growth of conjunctival fibrovascular tissue at day 7. The red pixel saturation and area of fibrovascular tissue developed was significantly higher in right eyes (p < 0.05). Tissues from both treatments showed neovascularization in lesser extent to that observed in human pterygium. Acanthosis, stromal inflammation, and edema were found in tissues of both treatments. No elastosis was found in either treatment. CONCLUSIONS: Matrigel alone or in combination with NIH3T3 cells injected into the rabbits' conjunctiva can promote tissue growth with characteristics of human pterygium, including neovascularization, acanthosis, stromal inflammation, and edema. The combination of Matrigel with NIH3T3 cells seems to have an additive effect on the size and redness of the pterygium-like tissue developed.

Injectable Tissue-Engineered Soft Tissue for Tissue Augmentation

Soft tissue augmentation is a process of implanting tissues or materials to treat wrinkles or soft tissue defects in the body. Over the years, various materials have evolved to correct soft tissue defects, including a number of tissues and polymers. Autogenous dermis, autogenous fat, autogenous dermis-fat, allogenic dermis, synthetic implants, and fillers have been widely accepted for soft tissue augmentations. Tissue engineering technology has also been introduced and opened a new venue of opportunities in this field. In particular, a long-lasting filler consisting of hyaluronic acid filler and living human mesenchymal cells called "injectable tissue-engineered soft tissue" has been created and applied clinically, as this strategy has many advantages over conventional methods. Fibroblasts and adipose-derived stromal vascular fraction cells can be clinically used as injectable tissue-engineered soft tissue at present. In this review, information on the soft tissue augmentation method using the injectable tissue-engineered soft tissue is provided.

Autologous transplantation in the central nervous system.

Cell transplantation has been proposed to replace lost neurons in the diseased brain, and after injuries to the central nervous system (CNS). Strategies for cellular therapy in the CNS consist primarily in heterologous transplantations. Despite the CNS being an immunologically privileged site, immune rejection of intracerebral transplants remains a concern. In addition, the use of immunosuppressive drugs, like cyclosporine, is a major constraint associated with heterologous transplantations. Autologous transplantation is therefore viewed as the model of choice for cellular therapy. With the recent progress in somatic cell nuclear transfer (SCNT) research, and the confirmation that neurogenesis occurs in the adult brain and neural stem cells (NSCs) reside in the adult CNS, new opportunities for autologous transplantations are being considered for the CNS, and are promising.

Effectiveness of liposomes to transfect livestock fibroblasts

The development of an efficient transfection system in livestock cells is an important step towards investigating gene transfer and the functioning and production of transgenic animals. Important factors involved in cationic liposome mediated gene transfer were evaluated through in vitro transfection of bovine, caprine and ovine fibroblast cells. Transfection of plasmid DNA complexes of different commercially available liposomes (Lipofectamine, Lipofectin, Cellfectin and DMRIE-C; Gibco-BRL, USA) was evaluated utilizing the following parameters: DNA/liposome ratio, cell density, DNA conformation, and the effect of transfection time on the efficiency of bovine fibroblasts to express a reporter gene. The effects and concentrations of liposomes were also evaluated in caprine and ovine fibroblasts. Lipofectamine alone and Lipofectamine with Plus reagent induced high-frequency expression of beta-galactosidase and neo genes in all cells evaluated (47 and 88.3%, respectively). Regarding phenotype, chromosomal stability was similar in transfected and non-transfected cells. The parameters set in this study will establish a foundation for utilizing transfected fibroblast cells to generate transgenic animals through nuclear transfer technology and gene function studies.

Regeneracion de defectos de tendon de Aquiles utilizando fibroblastos dermicos autologos: estudio experimental en conejos / Use of autologous dermal fibroblasts for massive Achilles tendon ruptures: an experimental study in rabbits

Introduccion: La ruptura del tendon de Aquiles constituye una de las lesiones mas frecuentes que afectan la pierna y el pie. El defecto que genera puede ser de gran magnitud en lesiones masivas e inveteradas. En este contexto, las opciones terapeuticas disponibles incluyen procedimientos reconstructivos complejos con la utilizacion de injertos antologos, cuyos resultados son dificiles de predecir. Por ello, en los ultimos años se han desarrollado diversas tecnicas de ingeniería tisular con el objeto de regenerar los defectos del tejido musculoesqueletico. El proposito de este estudio experimental es evaluar el potencial tendinogenico de fibroblastos autologos obtenidos de la dermis, para reparar defectos del tendon de Aquiles en conejos.Materiales y metodos: Se utilizo un modelo de defecto tendinoso segmentario en conejos neozelandeses en el cual se coloco una matriz de Hyaff 11 con fibroblastos dermicos expandidos in vitro contenida por una membrana de colageno, para regenerar el defecto. Como control se genero el mismo defecto sin procedimientos adicionales.Los neotendones fueron evaluados desde el punto de vista macroscopico e histologico a las 6 y 12 semanas posoperatorias. Se realizo el mismo procedimiento en el grupo control. Resultados: En el grupo experimental, se observo macroscopicamente un tejido continuo, de coloracion similar al nativo. Desde el punto de vista histologico a las 6 semanas se evidencio una gran proliferacion fibroblastica alrededor de los restos de la matriz de Hyaff 11. A las 12 semanas la celularidad del tejido neoformado fue menor y aumento la cantidad de fibras colagenas. No se observaron reacciones inflamatorias en los distintos puntos de observacion. Conclusiones: Los resultados de este estudio demuestran el potencial tendinogenico de los fibroblastos autologos obtenidos de la dermis para reparar defectos del tendon de Aquiles en conejos

Development of bovine embryos reconstructed by nuclear transfer of transfected and non-transfected adult fibroblast cells

An association of two techniques, nuclear transfer (NT), and transfection of somatic animal cells, has numerous potential applications and considerable impact, mainly in agriculture, medicine, pharmacy, and fundamental biology. In addition, somatic cell nuclear transfer is the most efficient alternative to produce large transgenic animals. We compared in vitro and in vivo developmental capacities of NT using fibroblast cells isolated from a 14-month-old cloned Simmental heifer (FCE) vs the same line transfected with a plasmid containing neomycin-resistant genes (TFCE). There were no significant differences (P > 0.5) in either fusion (116/149 = 78% vs 216/301 = 72%), cleavage (78/116 = 67% vs 141/216 = 65%) and blastocyst (35/116 = 30% vs 52/216 = 24%) rates or in pregnancy rate at 30 to 35 days after embryo transfer (2/17 vs 3/17) between NT using FCE and TFCE, respectively. Transfection and long-term in vitro culture of transfected cells did not affect developmental capacity of NT embryos up to 40 days of gestation