Induction of pluripotent stem cells by reprogramming human ocular fibroblasts under xeno-free conditions / Indução de células-tronco pluripotentes pela reprogramação de fibroblastos oculares humanos sob condições xeno-livre

ABSTRACT Purposes: To develop an efficient and xeno-free standard eye-derived induced pluripotent stem cell reprogramming protocol for use during induced pluripotent stem cell-based cell therapies in treating retinal degenerative diseases and to compare the relative effectiveness of both animal- and non-animal-derived culture systems in the generation of induced pluripotent stem cells. Methods: Primary cultured human pterygium fibroblasts and human Tenon's capsule fibroblasts were induced to induced pluripotent stem cells using a non-in­tegrated virus under two xeno-free systems; as part of this study, a traditional non-xeno-free reprogramming system was also assessed. Induced pluripotent stem cell clones were selected and counted by live staining. Reprogramming efficiencies were evaluated between the fibroblasts and among different culture systems. In a series of experiments, such as PCR and immunofluorescence staining, the induced pluripotent stem cells were characterized. Results: Human pterygium fibroblast- and human Tenon's capsule fibroblast-derived induced pluripotent stem cells were successfully established using different reprogramming systems, under which they exhibited properties of induced pluripotent stem cells. Reprogramming efficiencies of induced pluripotent stem cells using the cell therapy system, the traditional system, and the E6/E8 system were 0.014%, 0.028%, and 0.001%, respectively, and those of human pterygium fibroblast- and human Tenon's capsule fibroblast-derived induced pluripotent stem cells-using the aforementioned systems-were 0.018% and 0.017%, respectively. Conclusions: Sendai virus facilitates induced pluripotent stem cell reprogramming of ocular fibroblasts-both human pterygium and human Tenon's capsule fibroblasts being safe and efficient for induced pluripotent stem cell reprogramming. Although the reprogramming efficiencies of ocular-derived induced pluripotent stem cells under xeno-free conditions were not superior to those observed using the traditional reprogramming system, the cell therapy system reprogramming system is a good option when induced pluripotent stem cells are to be induced under xeno-free conditions.

RESUMO Objetivos: Desenvolver um protocolo padrão, eficiente e xeno-livre, para a reprogramação de células-tronco pluripotentes induzidas, que possa ser usado durante as terapias de células-tronco pluripotentes induzidas para o tratamento de doenças degenerativas da retina, e comparar a eficácia relativa de sistemas de cultivo de origem animal e de origem não animal na geração de células-tronco pluripotentes induzidas. Métodos: Cultivos primários de fibroblastos de pterígio humano e de fibroblastos da cápsula de Tenon humanos foram induzidos a células-tronco pluripotentes induzidas usando um vírus não integrado sob dois sistemas xeno-livres; um sistema tradicional de reprogramação não xeno-livre também foi avaliado como parte deste estudo. Os clones de células-tronco pluripotentes induzidas foram selecionados e contados por coloração de células vivas. As eficiências de reprogramação foram avaliadas entre os diferentes fibroblastos e entre os diferentes sistemas de cultivo. Uma série de experimentos, como o PCR e a coloração por imunofluorescência, foram conduzidos para caracterizar as células-tronco pluripotentes induzidas. Resultados: Célu­las-tronco pluripotentes induzidas derivadas de fibroblastos de pterígio humano e fibroblastos da cápsula de Tenon humanos foram estabelecidas com sucesso sob diferentes sistemas de reprogramação e exibiram propriedades de células-tronco pluripotentes induzidas. As eficiências de reprogramação das células-tronco pluripotentes induzidas usando o sistema de terapia celular, o sistema tradicional e o sistema E6/E8 foram 0,014, 0,028% e 0,001%, respectivamente. Além disso, as efi­ciências de reprogramação de células-tronco pluripotentes induzidas derivadas de fibroblastos de pterígio humano e de fibroblastos da cápsula de Tenon humanos usando todos os sistemas acima foram de 0,018% e 0,017%, respectivamente. Conclusões: O vírus Sendai pode ser usado para facilitar a reprogramação de fibroblastos oculares pelas células-tronco pluripotentes induzidas. Tanto os fibroblastos de pterígio humano quanto os fibroblastos da cápsula de Tenon humanos são seguros e eficientes para a reprogramação de células-tronco pluripotentes induzidas. Embora as eficiências de reprogramação das células-tronco pluripotentes induzidas de origem ocular sob condições xeno-livres não tenham sido superiores às eficiências observadas para o sistema tradicional de reprogramação, o sistema de reprogramação sistema de terapia celular é uma boa opção para a indução de células-tronco pluripotentes induzidas sob condições xeno-livres.

A simple and effective pressure culture system modified from a transwell cell culture system

Mechanical pressure plays an important role in many physiological and pathological processes. Mimicking the mechanical pressure present in vitro is necessary for related research, but usually requires expensive and complicated equipment. In this study we created a simple pressure culture system based on the transwell culture system. By cutting off the top rim of the transwell insert, the cells were compressed between the insert membrane and the well floor. The new pressure culture system was proven effective in that it induced cell morphological change, integrin β1 upregulation, actin polymerization and growth change in rat retinal ganglion cells, human nasopharyngeal carcinoma cells and mice embryonic fibroblasts. Though the pressure value is immeasurable and inhomogeneous, the easily available culture system still provides a choice for the laboratories that do not have access to the better, but much more expensive pressure culture equipment.

Long-term surgical outcomes of primary congenital glaucoma in China

OBJECTIVE: To evaluate the long-term outcomes of three surgical procedures for the treatment of primary congenital glaucoma (PCG). INTRODUCTION: PCG is one of the main causes of blindness in children. There is a paucity of contemporary data on PCG in China. METHODS: A retrospective study of 48 patients (81 eyes) with PCG who underwent primary trabeculectomy, trabeculotomy, or combined trabeculotomy and trabeculectomy (CTT). RESULTS: All patients were less than 4 years (yrs) of age, with a mean age of 2.08 ¡À 1.23 yrs. The mean duration of follow-up was 5.49 ¡À 3.09 yrs. The difference in success rates among the three surgical procedures at 1, 3, 6 and 9 yrs was not statistically significant (p = 0.492). However, in patients with over 4 yrs of follow-up, Kaplan-Meier survival analysis revealed that the success rates of trabeculectomy and CTT declined more slowly than that of trabeculotomy. Among the patients, 66.22% acquired good vision (VA ¡Ý 0.4), 17.57% acquired fair vision (VA = 0.1 - 0.3), and 16.22% acquired poor vision (VA < 0.1). The patients with good vision were mostly in the successful surgery group. Myopia was more prevalent postoperatively (p = 0.009). Reductions in the cup-disc ratio and corneal diameter were only seen in the successful surgery group (p = 0.000). In addition, the successful surgery group contained more patients that complied with a regular follow-up routine (p = 0.002). DISCUSSION: Our cases were all primary surgeries. Primary trabeculectomy was performed in many cases because no treatment was sought until an advanced stage of disease had been reached. CONCLUSIONS: In contrast to most reports, in the present study, trabeculectomy and CTT achieved higher long-term success rates than trabeculotomy. The patients with successful surgical results had better vision. Compliance with a routine of regular follow-up may increase the chances of a successful surgical outcome.

Effect on the Synthesis of 1,3 propanediol of Organic acids in the Two-stage Fermentation / 中国生物工程杂志

Effect of organic acids on the synthesis of 1,3 propanediol was studied.The adsorption of organic acids from glycerol fermentation liquor by ion-exchange resins was investigated.The results showed that organic acid and 1,3 propanediol production was in negative relationship.The static adsorption showed that ion-exchange resin 005 had the best adsorption abilities of the organic acids in the glycerol fermentation liquor.It was showed that the yield of 1,3propanediol increased by 166% after the extraction of organic acids from glycerol fermentation liquor and the convertion rate increased by 34%.

Secretory Expression of the Fusion Protein PTH-HSA in Pichia pastoris / 中国生物工程杂志

The fused gene (PTH-HSA) of parathyroid hormone (PTH) gene and Human Serum Albumin(HSA) gene was amplified without linker by Overlapping PCR technology. The spliced gene was clone into Pichia pastoris secretory vector pPIC9K. With the help of promoter AOX1 and mat ? signal peptide, the PTH-HSA gene was designed to secretory expression.Linearized by restriction enzyme SalI, The recombinant plasmid pPIC9K/PTH-HSA was transformed into Pichia pastoris KM71 by electroporation. The recombinant strains which were identified by G418 and PCR analysis were induced by methanol to express protein PTH-HSA. The target protein was expressed in fermentation supernatant. Western blot analysis of the fusion protein showed that the expressed fusion protein PTH-HSA had the antigenicity of HSA.adenylate cyclase assay proved that the fused protein exhibited the bioactivity to stimulate cAMP synthesis The specific activity of broth was about 318IU/ml.

Construction Fermentation of Engineered Strain and Properties of Recombinant ?-glutamyltranspeptidase / 中国生物工程杂志

The ?glutamyltranspeptidase encoding gene(ggt) from Bacillus subtilis SYU 20016 was amplified by PCR. The ggt gene was inserted in pBV220 to yield the recombinant expression vector pBV220ggt. Overexpression of ggt in E.coli JM109 was achieved with pBV220ggt. SDSPAGE analysis showed an overexpressed recombinant product at about 65kDa,consistent with the molecular weight predicted from gene sequence. The ferment conditions of r-glutamyltranspeptidase were also discussed. The optimum temperature and pH for the enzyme were determined as 30℃ and 7.2 respectively.The cultures were incubated at 42℃ for 4h with broth volume 20ml/250ml flask and the yield of 6U/ml was obtained, enzyme activity of B. subtilis NX2 was only 3.2 U/ml.

Heterologous Expression of Zygosacharomyces rouxii ZrGpd 1 in Pichia farinosa / 中国生物工程杂志

To examine the effects of heterologous expression of ZrGPD1 (encoding glycerol 3-phosphate dehydrogenase ) cloned from osmotolerant yeast Zygosacharomyces rouxii on glycerol production in wild Pichia farinosa,the URA3 gene was amplified from P. farinosa as the homology integrative region. A recombinant plasmid (pUR-ZG) was constructed then transformed into P. farinosa by electroporation. The transformant pfa-gu was obtained by the selectable marker Zeocin TM . Primary results showed that the biomass of pfa-gu was higher than the wild type in the flask and after 72h fermentation the concentration of glycerol of pfa-gu was 37g/L enhanced 30% in comparison with the wild type. It is concluded that heterologous expression of ZrGPD1 is useful for increasing glycerol production and the ability of osmoregulation in P. farinosa.

SCREENING AND MUTATING A RAW STARCH-DIGESTING GLUCOAMYLASE STRAIN / 微生物学通报

strains that could produce raw starch-digesting glucoamylase were isolated from soil and mildewed rice.The highest raw starch-digesting glucoamylase activity strain named OR-1 was identified as Rhizopus.sp.The raw starch-digesting glucoamylase activity of the strain is 90U/mL.Through UV and NTG mutagenesis,the raw starch-digesting glucoamylase activity raised to 200U/mL and 325U/mL respectively.The RDA were 70% and 65% respectively.

SCREENING OF MONASCUS PRODUCING ONLY YE LLOW PIGMENTS / 微生物学通报

mutants which didnt produce red pigmen ts on malt extract agar plate were obtained.The 8 stable mutants were cultured on solid medium.Two samples wer e yellow,the others were white.The extracted samples were scanned in visible len gth.2 yellow samples showed only one absorptive peak at 370nm,the 6 white sample s showed no absorptive peak.The mutants producing only yellow pigments on solid medium were tested in liquid culture.The results indicated their ability to pro duce only yellow pigments were stable.