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Human Fibroblast Growth Factor (human + fibroblast_growth_factor)
Selected AbstractsEngineering an improved crystal contact across a solvent-mediated interface of human fibroblast growth factor 1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2009Akshaya K. Meher Large-volume protein crystals are a prerequisite for neutron diffraction studies and their production represents a bottleneck in obtaining neutron structures. Many protein crystals that permit the collection of high-resolution X-ray diffraction data are inappropriate for neutron diffraction owing to a plate-type morphology that limits the crystal volume. Human fibroblast growth factor 1 crystallizes in a plate morphology that yields atomic resolution X-ray diffraction data but has insufficient volume for neutron diffraction. The thin physical dimension has been identified as corresponding to the b cell edge and the X-ray structure identified a solvent-mediated crystal contact adjacent to position Glu81 that was hypothesized to limit efficient crystal growth in this dimension. In this report, a series of mutations at this crystal contact designed to both reduce side-chain entropy and replace the solvent-mediated interface with direct side-chain contacts are reported. The results suggest that improved crystal growth is achieved upon the introduction of direct crystal contacts, while little improvement is observed with side-chain entropy-reducing mutations alone. [source] Local stimulation of articular cartilage repair by transplantation of encapsulated chondrocytes overexpressing human fibroblast growth factor 2 (FGF-2) in vivo,THE JOURNAL OF GENE MEDICINE, Issue 1 2006Gunter Kaul Abstract Background Defects of articular cartilage are an unsolved problem in orthopaedics. In the present study, we tested the hypothesis that gene transfer of human fibroblast growth factor 2 (FGF-2) via transplantation of encapsulated genetically modified articular chondrocytes stimulates chondrogenesis in cartilage defects in vivo. Methods Lapine articular chondrocytes overexpressing a lacZ or a human FGF-2 gene sequence were encapsulated in alginate and further characterized. The resulting lacZ or FGF-2 spheres were applied to cartilage defects in the knee joints of rabbits. In vivo, cartilage repair was assessed qualitatively and quantitatively at 3 and 14 weeks after implantation. Results In vitro, bioactive FGF-2 was secreted, leading to a significant increase in the cell numbers in FGF-2 spheres. In vivo, FGF-2 continued to be expressed for at least 3 weeks without leading to differences in FGF-2 concentrations in the synovial fluid between treatment groups. Histological analysis revealed no adverse pathologic effects on the synovial membrane at any time point. FGF-2 gene transfer enhanced type II collagen expression and individual parameters of chondrogenesis, such as the cell morphology and architecture of the new tissue. Overall articular cartilage repair was significantly improved at both time points in vivo. Conclusions The data suggest that localized overexpression of FGF-2 enhances the repair of cartilage defects via stimulation of chondrogenesis, without adverse effects on the synovial membrane. These results may lead to the development of safe gene-based therapies for human articular cartilage defects. Copyright © 2005 John Wiley & Sons, Ltd. [source] Overexpression of human fibroblast growth factor 2 stimulates cell proliferation in an ex vivo model of articular chondrocyte transplantation,THE JOURNAL OF GENE MEDICINE, Issue 2 2004Henning Madry Abstract Background Genetically engineered chondrocytes could be used to enhance cartilage repair. Fibroblast growth factor 2 (FGF-2) is a mitogen for chondrocytes and may be a candidate for gene transfer approaches to stimulate chondrocyte proliferation. In the present study, we tested the hypothesis that human FGF-2 (hFGF-2) gene transfer into articular chondrocytes modulates cell proliferation in an ex vivo model of chondrocyte transplantation. Methods Transfection of articular chondrocytes with an expression plasmid vector carrying the cDNA for hFGF-2 under the control of the cytomegalovirus promoter/enhancer mediated transgene expression and synthesis of biologically relevant amounts of the recombinant hFGF-2 protein. Articular chondrocytes transfected with the Escherichia coli ,-galactosidase (lacZ) gene or a hFGF-2 cDNA were transplanted onto the surface of articular cartilage explants. Results The tissue formed by the chondrocytes expressing hFGF-2 was thicker and contained more cells than control cultures. Quantitative analysis of [3H]thymidine and [35S]sulfate incorporation in composite cultures revealed that hFGF-2 transfection stimulated mitogenic activity in the new tissue but did not augment matrix glycosaminoglycan synthesis. Conclusions These data support the concept that chondrocytes overexpressing a hFGF-2 cDNA selectively modulate cell proliferation in an ex vivo model of chondrocyte transplantation. These results suggest that therapeutic hFGF-2 gene transfer may be applicable for the treatment of articular cartilage disorders, such as traumatic defects in which cellular repopulation is a therapeutic goal. Copyright © 2004 John Wiley & Sons, Ltd. [source] Structure of a highly stable mutant of human fibroblast growth factor 1ACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2009Anna Szlachcic Fibroblast growth factors (FGFs) are involved in diverse cellular processes such as cell migration, angiogenesis, osteogenesis, wound healing and embryonic and foetal development. Human acidic fibroblast growth factor (FGF-1) is the only member of the FGF family that binds with high affinity to all four FGF receptors and thus is considered to be the human mitogen with the broadest specificity. However, pharmacological applications of FGF-1 are limited owing to its low stability. It has previously been reported that the introduction of single mutations can significantly improve the stability of FGF-1 and its resistance to proteolytic degradation. Here, the structure of the Q40P/S47I/H93G triple mutant of FGF-1, which exhibits much higher stability, a prolonged half-life and enhanced mitogenic activity, is presented. Compared with the wild-type structure, three localized conformational changes in the stable triple mutant were observed, which is in agreement with the perfect energetic additivity of the single mutations described in a previous study. The huge change in FGF-1 stability (the denaturation temperature increased by 21.5,K, equivalent to ,,Gden = 24.3,kJ,mol,1) seems to result from the formation of a short 310 -helix (position 40), an improvement in the propensity of amino acids to form ,-sheets (position 47) and the rearrangement of a local hydrogen-bond network (positions 47 and 93). [source] Engineering an improved crystal contact across a solvent-mediated interface of human fibroblast growth factor 1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2009Akshaya K. Meher Large-volume protein crystals are a prerequisite for neutron diffraction studies and their production represents a bottleneck in obtaining neutron structures. Many protein crystals that permit the collection of high-resolution X-ray diffraction data are inappropriate for neutron diffraction owing to a plate-type morphology that limits the crystal volume. Human fibroblast growth factor 1 crystallizes in a plate morphology that yields atomic resolution X-ray diffraction data but has insufficient volume for neutron diffraction. The thin physical dimension has been identified as corresponding to the b cell edge and the X-ray structure identified a solvent-mediated crystal contact adjacent to position Glu81 that was hypothesized to limit efficient crystal growth in this dimension. In this report, a series of mutations at this crystal contact designed to both reduce side-chain entropy and replace the solvent-mediated interface with direct side-chain contacts are reported. The results suggest that improved crystal growth is achieved upon the introduction of direct crystal contacts, while little improvement is observed with side-chain entropy-reducing mutations alone. [source] Aplasia cutis congenita with skull defect in a monozygotic twin after exposure to methimazole in uteroBIRTH DEFECTS RESEARCH, Issue 10 2007Hideyuki Iwayama Abstract BACKGROUND: Aplasia cutis congenita (ACC) is a condition in which localized or widespread areas of skin are absent at birth. Defective lesions show complete absence of all layers of skin, occasionally extending to skull or dura. ACC is etiologically heterogeneous; many different etiologies including teratogens have been documented. CASE: We describe the first reported case of a monozygotic twin with ACC after exposure to methimazole in utero. The female patient was born at 36 weeks gestation as the first child of monozygotic twins. The mother received methimazole between the 11th and 17th weeks of pregnancy because of transient hyperthyroidism. The second child did not have ACC. The patient had defects of the scalp, skull, and dura (7 × 5 cm) on the sagittal line of the parieto-occipital region. No other malformations were noted. The scalp defect has been treated daily with sterile physiological saline and petrolatum dressing in addition to intravenous antibiotics. Trafermin, a recombinant human fibroblast growth factor, was sprayed from day 6 to promote epithelialization of the scalp defect. On day 21, she had high fever due to infection of the defect lesion, which was controlled by povidone iodine dressing and intravenous antibiotics. The defect of the scalp was well healed after 6 weeks, but the skull defect remained unclosed. CONCLUSIONS: We describe a rare case of a monozygotic twin with ACC and skull defect after methimazole exposure in utero. The findings of our case suggest that methimazole is a potential teratogen of ACC. Birth Defects Research (Part A) 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||