MicroRNA (miR)-125b has been shown to play a potential role in the development of glioma stem cells.However,the relationship between miRNA and glioma stem cells is still elusive.This study was designed to elucidate th...MicroRNA (miR)-125b has been shown to play a potential role in the development of glioma stem cells.However,the relationship between miRNA and glioma stem cells is still elusive.This study was designed to elucidate this potential relationship.We established a highly invasive glioma stem cell and progenitor (GSCP) cell line SU3.SU3 cell suspensions were injected into nude mice brains in situ,and the invasiveness of graft tumors was analyzed using hematoxylin and eosin staining as well as immunohistochemistry.Real-time polymerase chain reaction (PCR) was used to measure the expression levels of miR-125b in SU3 and other cells.In vitro,SU3 cells expressed CD133 and nestin as well as differentiation markers glial fibrillary acidic protein (GFAP) and β-tubulin III,which were consistent with the characteristics of glioma stem cells.Scratch assays indicated that the migration ability of SU3 cells was stronger than that of U251 stem cells (U251s).In vivo,SU3 cells invaded into each part of the mouse brain from the caudate nucleus in a diffuse pattern and highly expressed invasive and proliferative cell markers matrix metalloprotease 2 (MMP2),MMP9,and Ki-67.Real-time PCR results revealed that the levels of miR-125b and MMP9 were significantly higher in SU3 and SU2,also a highly invasive GSCP cell line we established before,than in U251s.High expression of miR-125b both in newly established GSCPs,SU3,and long-term cultured GSCPs,SU2 suggests that miR-125b exhibits oncogene-like behavior.This behavior should be considered in further studies of miR-125b in cancer stem cells.Furthermore,MMP9,which plays a role in cancer stem cell invasion,may be a target gene of miR-125b.展开更多
粉纹夜蛾颗粒体病毒(Trichoplusia ni granulovirus,TnGV)增强蛋白(enhancin)具有增强病毒感染力的作用。该蛋白包含一个多种杆状病毒增强蛋白都具有的保守结构域HELGH,是典型的金属蛋白酶锌离子结合域,但该结构域对增强蛋白生物活性的...粉纹夜蛾颗粒体病毒(Trichoplusia ni granulovirus,TnGV)增强蛋白(enhancin)具有增强病毒感染力的作用。该蛋白包含一个多种杆状病毒增强蛋白都具有的保守结构域HELGH,是典型的金属蛋白酶锌离子结合域,但该结构域对增强蛋白生物活性的重要性尚未得到研究。本研究通过定点突变构建了该结构域的5个氨基酸分别突变为2种不同氨基酸的共10种增强蛋白突变体基因,并用杆状病毒载体进行了重组表达。活性测定发现,10种突变型增强蛋白大部分都丧失了野生型增强蛋白所具有的降解粉纹夜蛾幼虫围食膜粘蛋白的生物学功能,只有1种(第4位G突变为A)保留该生物学活性。这一结果表明锌离子结合域对增强蛋白生物活性具有重要作用,也提示增强蛋白确是一种金属蛋白酶。展开更多
In an attempt to isolate and characterize peptides mimicking epitopes of metalloprotease and explore their immunological protection against Schistosoma japonicum （S. japonicum）, polyclonal anti-metalloprotease sera ...In an attempt to isolate and characterize peptides mimicking epitopes of metalloprotease and explore their immunological protection against Schistosoma japonicum （S. japonicum）, polyclonal anti-metalloprotease sera was prepared to screen a 12-mer random peptide library to isolate phages binding specially to antisera IgG. Then, phage ELISA, animal immunization, DNA sequencing, Western blotting and enzymatic activity neutralizing analysis were used to characterize the selected phage clones. All of ten randomly picked clones were shown to be positive. Five peptides of different amino acid sequences deduced from DNA sequences were obtained and two of them （peptides 2 and 3） could induce significant reduction （31.0% and 31.8%, respectively） in worm burden and high reduction （52.6% and 54.9%, respectively） in liver eggs per gram （LEPG）, while, unexpectedly, others （peptides 1, 4 and 5） could not elicit enough protection against infection of S. japonicum. Peptides 2 and 3 could be recognized by S. japonicum infected mouse sera （IMS） and could elicit neutralizing Abs. The results show that peptides 2 and 3 are antigenic and immunogenic. They are true mimics of epitopes of metalloprotease and useful as novel vaccine candidates against S.japonicum. Cellular ＆ Molecular Immunology. 2005;2（3）：219-223.展开更多
基金funded by grants from the Natural Science Foundation of China(NO.81172400,81000963)the Natural Science Foundation of Jiangsu Province(NO.BK2011341)the Natural Science Foundation of Suzhou(NO.SYS201063,SYS201161)
文摘MicroRNA (miR)-125b has been shown to play a potential role in the development of glioma stem cells.However,the relationship between miRNA and glioma stem cells is still elusive.This study was designed to elucidate this potential relationship.We established a highly invasive glioma stem cell and progenitor (GSCP) cell line SU3.SU3 cell suspensions were injected into nude mice brains in situ,and the invasiveness of graft tumors was analyzed using hematoxylin and eosin staining as well as immunohistochemistry.Real-time polymerase chain reaction (PCR) was used to measure the expression levels of miR-125b in SU3 and other cells.In vitro,SU3 cells expressed CD133 and nestin as well as differentiation markers glial fibrillary acidic protein (GFAP) and β-tubulin III,which were consistent with the characteristics of glioma stem cells.Scratch assays indicated that the migration ability of SU3 cells was stronger than that of U251 stem cells (U251s).In vivo,SU3 cells invaded into each part of the mouse brain from the caudate nucleus in a diffuse pattern and highly expressed invasive and proliferative cell markers matrix metalloprotease 2 (MMP2),MMP9,and Ki-67.Real-time PCR results revealed that the levels of miR-125b and MMP9 were significantly higher in SU3 and SU2,also a highly invasive GSCP cell line we established before,than in U251s.High expression of miR-125b both in newly established GSCPs,SU3,and long-term cultured GSCPs,SU2 suggests that miR-125b exhibits oncogene-like behavior.This behavior should be considered in further studies of miR-125b in cancer stem cells.Furthermore,MMP9,which plays a role in cancer stem cell invasion,may be a target gene of miR-125b.
文摘粉纹夜蛾颗粒体病毒(Trichoplusia ni granulovirus,TnGV)增强蛋白(enhancin)具有增强病毒感染力的作用。该蛋白包含一个多种杆状病毒增强蛋白都具有的保守结构域HELGH,是典型的金属蛋白酶锌离子结合域,但该结构域对增强蛋白生物活性的重要性尚未得到研究。本研究通过定点突变构建了该结构域的5个氨基酸分别突变为2种不同氨基酸的共10种增强蛋白突变体基因,并用杆状病毒载体进行了重组表达。活性测定发现,10种突变型增强蛋白大部分都丧失了野生型增强蛋白所具有的降解粉纹夜蛾幼虫围食膜粘蛋白的生物学功能,只有1种(第4位G突变为A)保留该生物学活性。这一结果表明锌离子结合域对增强蛋白生物活性具有重要作用,也提示增强蛋白确是一种金属蛋白酶。
文摘In an attempt to isolate and characterize peptides mimicking epitopes of metalloprotease and explore their immunological protection against Schistosoma japonicum （S. japonicum）, polyclonal anti-metalloprotease sera was prepared to screen a 12-mer random peptide library to isolate phages binding specially to antisera IgG. Then, phage ELISA, animal immunization, DNA sequencing, Western blotting and enzymatic activity neutralizing analysis were used to characterize the selected phage clones. All of ten randomly picked clones were shown to be positive. Five peptides of different amino acid sequences deduced from DNA sequences were obtained and two of them （peptides 2 and 3） could induce significant reduction （31.0% and 31.8%, respectively） in worm burden and high reduction （52.6% and 54.9%, respectively） in liver eggs per gram （LEPG）, while, unexpectedly, others （peptides 1, 4 and 5） could not elicit enough protection against infection of S. japonicum. Peptides 2 and 3 could be recognized by S. japonicum infected mouse sera （IMS） and could elicit neutralizing Abs. The results show that peptides 2 and 3 are antigenic and immunogenic. They are true mimics of epitopes of metalloprotease and useful as novel vaccine candidates against S.japonicum. Cellular ＆ Molecular Immunology. 2005;2（3）：219-223.
