Corynebacterium pseudotuberculosis is an infectious agent that occurs in small ruminants causing caseous lymphadenitis, and more rarely in humans causing lymphadenitis and pneumonia. The breeding small ruminants have ...Corynebacterium pseudotuberculosis is an infectious agent that occurs in small ruminants causing caseous lymphadenitis, and more rarely in humans causing lymphadenitis and pneumonia. The breeding small ruminants have great economic importance in Brazil. Rural farm workers and veterinary students who acquired this disease suffered from weakening symptoms for weeks, and the identification of the etiological agent was time-consuming and complex. Due to the low prevalence of case records, there is probably no available commercial diagnostic kit for C. pseudotuberculosis infection in humans. This study aimed to describe human seroreactivity to secreted antigens from C. pseudotuberculosis. Reactivity of serum from farm workers (n = 14), individuals who work with the bacillus at laboratory (n = 8) or individuals without contact (n = 25) was tested with secreted proteins from PAT10 strain of C. pseudotuberculosis by Western blotting. Samples of all (100%) farm workers showed reactivity to 31 kDa, 71 kDa and 164 kDa proteins, while laboratory workers showed 87.5%, 62.5 % and 37.5%, and no-contact 20%, 0% and 16%, respectively. All sera recognized the 275 kDa protein. Our data suggest that C. pseudotuberculosis secreted proteins are antigenic in humans and the recognition profiles allowed the identification of individuals with and without prior contact with this bacillus. This is the first paper which describes human reactivity to C. pseudotuberculosis in serum samples of workers in Brazil.展开更多
It has been demonstrated that tbe critical role ofbone marrow stromal cells (HMSCs ) is to sustain theselfrenewal of pluripotent hematopoietic stem cells andmaintain the homeostasis of bone marrow hematopoiesismicroen...It has been demonstrated that tbe critical role ofbone marrow stromal cells (HMSCs ) is to sustain theselfrenewal of pluripotent hematopoietic stem cells andmaintain the homeostasis of bone marrow hematopoiesismicroenvironment. BMSC progenitor can differentiateinto several clements including macrophages, endothelialcells, fibroblasts and some other cells. Almost展开更多
AIM: To investigate a possible increase of basolateral expression of carcinoembryonic antigen (CEA) by interfering with the apical transport machinery, we studied the effect of cholesterol depletion on CEA sorting and...AIM: To investigate a possible increase of basolateral expression of carcinoembryonic antigen (CEA) by interfering with the apical transport machinery, we studied the effect of cholesterol depletion on CEA sorting and secretion. METHODS: Cholesterol depletion was performed in polarized Caco-2 cells using lovastatin and methyl-b- cyclodextrin. RESULTS: We show that CEA is predominantly expressed and secreted at the apical surface. Reduction of the cholesterol level of the cell by 40%-50% with lovastatin and methyl-b-cyclodextrin led to a significant change of the apical-to-basolateral transport ratio towards the basolateral membrane. CONCLUSION: As basolateral expression of CEA has been suggested to have anti-inflamatory properties, Cholesterol depletion of enterocytes might be a potential approach to influence the course of inflammatory bowel disease.展开更多
The N-terminal 54 base pairs (encoding amino acid residues 2—19) within the preS1 region of the human hepatitis B virus surface antigen gene were deleted by site-directed mutagenesis. Unlike the wild type large surfa...The N-terminal 54 base pairs (encoding amino acid residues 2—19) within the preS1 region of the human hepatitis B virus surface antigen gene were deleted by site-directed mutagenesis. Unlike the wild type large surface antigen protein; when this mutated gene was expressed in monkey kidney cell line COS-M6, the protein product (S301 protein) could be secreted from the cells. Moreover, the inhibition of the secretion of the major surface antigen protein by this altered large surface antigen protein was greatly reduced, suggesting that the deleted region contained a retention sequence which prevented the secretion of the large surface antigen. However, the coexpression of the major S protein was essential for the secretion of the S301 protein. When coexpressed, the secretion of these two proteins was synchronous. Like the wild type large surface antigen protein, the S301 protein could be translocated into ertdoplasmic reticulum and glycosylated after its synthesis in COS cells. The S301 protein was thermostable and proteinase-resistant. It also retained the antigenicity of the large S and major S proteins. Given the fact that the S301 protein is readily secretable, stable and identical to the large S protein in terms of their antigenicity, it may be developed into a new generation of recombinant vaccine for the prevention of viral hepatitis.展开更多
目的观察弓形虫感染小鼠腹水中分离的排泄-分泌抗原（excreted/secreted antigens,ESA）鼻内免疫小鼠对不同粘膜部位和系统的免疫效应。方法将5～6周龄BALB/c小鼠随机分为4组,每组10只,实验组分别用从感染弓形虫后24、48、72 h小鼠腹...目的观察弓形虫感染小鼠腹水中分离的排泄-分泌抗原（excreted/secreted antigens,ESA）鼻内免疫小鼠对不同粘膜部位和系统的免疫效应。方法将5～6周龄BALB/c小鼠随机分为4组,每组10只,实验组分别用从感染弓形虫后24、48、72 h小鼠腹水中提取的ESA 20μg/只鼻内免疫小鼠2次,间隔2周;对照组用20μl/只PBS滴鼻。观察小鼠健康和死亡情况,记录体重。末次免疫后第3周处死小鼠,计数PP（Peyer’s patches）个数;分离PP淋巴细胞、脾淋巴细胞、小肠上皮内淋巴细胞（intraepithelial lymphocyte,IEL）及肠系膜淋巴结细胞（mesenteric lymph node lympho-cyte,MLNL）并计数。眼眶采血和收集直肠内粪便,ELISA检测血清特异性IgG水平及粪便sIgA。结果72 h ESA组小鼠免疫后健康状况较差,体重逐渐降低,死亡4只;其他组小鼠体重仍呈增高趋势。各实验组小鼠IEL、MLNL、脾淋巴细胞以及PP淋巴细胞的增殖活性均高于对照组（P〈0.05）,72 h和48 h ESA组高于24 h ESA组（P〈0.01）。免疫后第3周,各实验组小鼠血清IgG、粪便sIgA水平均高于对照组（P〈0.05）,72 h和48 h ESA组高于24 h ESA组（P〈0.01）。结论感染后不同时间提取的腹水弓形虫ESA鼻内免疫小鼠均可诱导不同粘膜部位及系统特异性的免疫应答,48 h ESA的免疫效果最好。展开更多
文摘Corynebacterium pseudotuberculosis is an infectious agent that occurs in small ruminants causing caseous lymphadenitis, and more rarely in humans causing lymphadenitis and pneumonia. The breeding small ruminants have great economic importance in Brazil. Rural farm workers and veterinary students who acquired this disease suffered from weakening symptoms for weeks, and the identification of the etiological agent was time-consuming and complex. Due to the low prevalence of case records, there is probably no available commercial diagnostic kit for C. pseudotuberculosis infection in humans. This study aimed to describe human seroreactivity to secreted antigens from C. pseudotuberculosis. Reactivity of serum from farm workers (n = 14), individuals who work with the bacillus at laboratory (n = 8) or individuals without contact (n = 25) was tested with secreted proteins from PAT10 strain of C. pseudotuberculosis by Western blotting. Samples of all (100%) farm workers showed reactivity to 31 kDa, 71 kDa and 164 kDa proteins, while laboratory workers showed 87.5%, 62.5 % and 37.5%, and no-contact 20%, 0% and 16%, respectively. All sera recognized the 275 kDa protein. Our data suggest that C. pseudotuberculosis secreted proteins are antigenic in humans and the recognition profiles allowed the identification of individuals with and without prior contact with this bacillus. This is the first paper which describes human reactivity to C. pseudotuberculosis in serum samples of workers in Brazil.
文摘It has been demonstrated that tbe critical role ofbone marrow stromal cells (HMSCs ) is to sustain theselfrenewal of pluripotent hematopoietic stem cells andmaintain the homeostasis of bone marrow hematopoiesismicroenvironment. BMSC progenitor can differentiateinto several clements including macrophages, endothelialcells, fibroblasts and some other cells. Almost
基金The Dietmar Hopp Foundation and the Stiftung Nephrologie
文摘AIM: To investigate a possible increase of basolateral expression of carcinoembryonic antigen (CEA) by interfering with the apical transport machinery, we studied the effect of cholesterol depletion on CEA sorting and secretion. METHODS: Cholesterol depletion was performed in polarized Caco-2 cells using lovastatin and methyl-b- cyclodextrin. RESULTS: We show that CEA is predominantly expressed and secreted at the apical surface. Reduction of the cholesterol level of the cell by 40%-50% with lovastatin and methyl-b-cyclodextrin led to a significant change of the apical-to-basolateral transport ratio towards the basolateral membrane. CONCLUSION: As basolateral expression of CEA has been suggested to have anti-inflamatory properties, Cholesterol depletion of enterocytes might be a potential approach to influence the course of inflammatory bowel disease.
基金This research was supported in part by U. S. Public Health Service Grants CA-70175 and CA-2243 to J. Mertz from the U. S. National Institute of Health.
文摘The N-terminal 54 base pairs (encoding amino acid residues 2—19) within the preS1 region of the human hepatitis B virus surface antigen gene were deleted by site-directed mutagenesis. Unlike the wild type large surface antigen protein; when this mutated gene was expressed in monkey kidney cell line COS-M6, the protein product (S301 protein) could be secreted from the cells. Moreover, the inhibition of the secretion of the major surface antigen protein by this altered large surface antigen protein was greatly reduced, suggesting that the deleted region contained a retention sequence which prevented the secretion of the large surface antigen. However, the coexpression of the major S protein was essential for the secretion of the S301 protein. When coexpressed, the secretion of these two proteins was synchronous. Like the wild type large surface antigen protein, the S301 protein could be translocated into ertdoplasmic reticulum and glycosylated after its synthesis in COS cells. The S301 protein was thermostable and proteinase-resistant. It also retained the antigenicity of the large S and major S proteins. Given the fact that the S301 protein is readily secretable, stable and identical to the large S protein in terms of their antigenicity, it may be developed into a new generation of recombinant vaccine for the prevention of viral hepatitis.
文摘目的观察弓形虫感染小鼠腹水中分离的排泄-分泌抗原（excreted/secreted antigens,ESA）鼻内免疫小鼠对不同粘膜部位和系统的免疫效应。方法将5～6周龄BALB/c小鼠随机分为4组,每组10只,实验组分别用从感染弓形虫后24、48、72 h小鼠腹水中提取的ESA 20μg/只鼻内免疫小鼠2次,间隔2周;对照组用20μl/只PBS滴鼻。观察小鼠健康和死亡情况,记录体重。末次免疫后第3周处死小鼠,计数PP（Peyer’s patches）个数;分离PP淋巴细胞、脾淋巴细胞、小肠上皮内淋巴细胞（intraepithelial lymphocyte,IEL）及肠系膜淋巴结细胞（mesenteric lymph node lympho-cyte,MLNL）并计数。眼眶采血和收集直肠内粪便,ELISA检测血清特异性IgG水平及粪便sIgA。结果72 h ESA组小鼠免疫后健康状况较差,体重逐渐降低,死亡4只;其他组小鼠体重仍呈增高趋势。各实验组小鼠IEL、MLNL、脾淋巴细胞以及PP淋巴细胞的增殖活性均高于对照组（P〈0.05）,72 h和48 h ESA组高于24 h ESA组（P〈0.01）。免疫后第3周,各实验组小鼠血清IgG、粪便sIgA水平均高于对照组（P〈0.05）,72 h和48 h ESA组高于24 h ESA组（P〈0.01）。结论感染后不同时间提取的腹水弓形虫ESA鼻内免疫小鼠均可诱导不同粘膜部位及系统特异性的免疫应答,48 h ESA的免疫效果最好。
