ABSTRACT
Collagen vitrigel membranes are transparent biomaterials characterized by a densely organized, fibrillar nanostructure that show promise in the treatment of corneal injury and disease. In this study, the influence of different type I collagen sources and processing techniques, including acid-solubilized collagen from bovine dermis (Bov), pepsin-solubilized collagen from human fibroblast cell culture (HuCC), and ficin-solubilized collagen from recombinant human collagen expressed in tobacco leaves (rH), on the properties of the vitrigel membranes was evaluated. Postvitrification carbodiimide crosslinking (CX) was also carried out on the vitrigels from each collagen source, forming crosslinked counterparts BovXL, HuCCXL, and rHXL, respectively. Collagen membrane ultrastructure and biomaterial properties were found to rely heavily on both collagen source and crosslinking. Bov and HuCC samples showed a random fibrillar organization of collagen, whereas rH vitrigels showed remarkable regional fibril alignment. After CX, light transmission was enhanced in all groups. Denaturation temperatures after CX increased in all membranes, of which the highest increase was seen in rH (14.71°C), suggesting improved thermal stability of the collagen fibrils in the membranes. Noncrosslinked rH vitrigels may be reinforced through CX to reach levels of mechanical strength and thermal stability comparable to Bov.
Subject(s)
Collagen/chemistry , Membranes, Artificial , Vitrification , Animals , Cattle , Dermis/chemistry , Humans , Recombinant Proteins/chemistryABSTRACT
Autoimmune diseases are characterized by immune response against self antigens. One of the current research interests in this field is oriented toward development of tolerance. One of the newest options in the search for tolerance is autologous bone marrow transplantation: a variant of bone marrow transplant in which the patient's own hematopoietic stem cells are reinfused after myeloablative therapy. The idea of using bone marrow transplant in treatment of autoimmune diseases derived from observing remission in autoimmune diseases in patients transplanted due to coexisting neoplastic disease. Although an isolated initial report of bone marrow transplant as treatment for autoimmune disease questioned the utility of this procedure, over all, results are encouraging. To compile information in a programmed and systematic manner, it is necessary to send more patients in all stages of immune diseases to specialized centers to be included in large multicenter randomized trials. In time, the role for this procedure in autoimmune diseases will become clear.
Subject(s)
Autoimmune Diseases/surgery , Bone Marrow Transplantation , Arthritis, Juvenile/surgery , Arthritis, Rheumatoid/surgery , Humans , Lupus Erythematosus, Systemic/surgery , Multiple Sclerosis/surgery , Scleroderma, Systemic/surgery , Treatment OutcomeABSTRACT
Las enfermedades autoinmunes se caracterizan por una respuesta del sistema inmune del individuo hacia tejidos propios. Una línea de investigación actual es el tratamiento de estas enfermedades y el desarrollo de tolerancia. Una de las opciones en la búsqueda del desarrollo de tolerancia es el trasplante autólogo de médula ósea: la variantes del trasplante de médula ósea que hace uso de células progenitoras hematopoyéticas propias. La posibilidad de usar este tipo de trasplante como tratamiento de enfermedades autoinmunes se originó en los hallazgos de remisiones de enfermedades autoinmunes coexistentes, en pacientes que eran trasplantados por enfermedades oncológicas. En esta revisión presentemos el fundamento teórico de este tratamiento, así como una recopilación de los estudios preclínicos y clínicos más relevantes en esta materia. Aunque algún reporte inicial puso en duda la utilidad de dicho procedimiento, en general, los resultados son alentadores. Es necesario que más pacientes en diversos estadios de las enfermedades autoinmunes sean referidos a centros especializados de manera que sea posible recopilar la información de manera ordenada y sistemática, y se pueda arribar a un conocimiento sobre el papel que juega este tipo de tratamiento en las enfermedades autoinmunes.
Autoimmune diseases are characterized by immune response against self antigens. One of the current research interests in this field is oriented toward development of tolerance. One of the newest options in the search for tolerance is autologous bone marrow transpiantation: a variant of bone marrow transplant in which the patient's own hematopoietic stem cells are reinfused after myeloablative therapy. The idea of using bone marrow transplant in treatment of autoimmune diseases derived from observing remission in autoinmune diseases in patients transplanted due to coexisting neoplastic disease. Although an isolated initial report of bone marrow transplant as treatment for autoimmune disease questioned the utility of this procedure, over all, results are encouraging. To compile information in a programmed and systematic manner, it is necessary to send more patients in all stages of immune diseases to specialized centers to be included in large multicenter randomized trials. In time, the role for this procedure in autoimmune diseases will become clear.
