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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Interaction studies of idiotypic and antiidiotypic antibodies at experimental tumor targeting /

Erlandsson, Ann, January 2005 (has links)
Diss. (sammanfattning) Umeå : Univ., 2005. / Härtill 5 uppsatser.
2

Undersökning av affinitet till TS1-218, TS1-218<sub>2</sub> och HE1-Q enkelkedjeantikroppar i multicellulära tumörsfäroider cytokeratin 8 för TS1-218, TS1-218<sub>2</sub> och HE1-Q enkelkedjeantikroppar i multicellulära tumörsfäroider / Investigation of affinity to cytokeratin 8 in multicellular tumor spheroids for TS1-218, TS1-218<sub>2</sub> and HE1-Q single chain variable fragment antibodies

Piercecchi, Marco January 2009 (has links)
<p>In vitro-test för upptäckt och behandling av tumör eller mikrometastaser har de senaste 30 åren gjort stora framsteg tack vare immunokemi och nya framgångsrika cellodlings- tekniker som bättre reproducerar celltillväxt i tre dimensioner (3D) och det omgivande stromat (multicellulär tumörsfäroidodling). TS1-218 scFv (single chain variable fragment) är en monoklonal antikropp som har affinitet till ett protein tillhörande cytoskelettet (cytokeratin). Av TS1-218 har skapats olika varianter (en dimer TS1-218<sub>2</sub> och en mutant HE1-Q) med syftet att öka affinitet och retentionstid på platsen för dess verkan. I det här projektet försökte vi att testa och jämföra egenskaper hos alla 3 joderade antikropparna genom att inkubera odlade Hela Hep 2 tumörcellssfäroider med dessa antikroppar. Alla tre antikroppsvarianter visade god förmåga att penetrera sfäroider och att binda deras epitop i cytokeratin 8. Försöken visade att det fanns affinitetsskillnader mellan TS1-218 monomer, dimer och mutant vilket visade sig som olika inbindningsförmåga till sfäroiderna.</p>
3

Immunhistokemisk undersökning av paraffinbäddade celler från pleuravätska som kompletterande underlag för diagnos av cancermetastaser

Ahrén, Anna January 2005 (has links)
<p>Background. Immunohistochemistry is a useful method in the differential diagnosis between pleural mesotheliomas and metastatic adenocarcinomas in the pleura. Cytokeratin 20 and 7 have been used successfully as markers in studies determining primary location of adenocarcinomas from metastases. The current study is a complementary research of archived paraffininbedded material of cases with cancer origin. This study contributes a bigger statistical material that may facilitate the search for unknown primary site of adenocarcinoma by identification of metastatic cells in the pleura.</p><p>Methods. Cells from the pleura taken from fifteen patients with diagnosed cancer of different types and eleven patients with cancer of unknown origin, were stained with antibodies against the tumour markers: Ber EP 4, calretinin, cytokeratin 20 and 7, estrogen receptor α, thyroid transcription factor, prostate-specific antigen and Cdx2.The staining was conducted in an automated immunohistochemical system. The staining of each kind of antibody was confirmed by a control section staining.</p><p>Results. All control staining ended perfect The whole panel of antibodies used on mammary cancer showed the same pattern for every antibody. Of the patients with cancer of unknown origin there were four that gave the same pattern, two men and two women. The women are deceased. To make a more careful evaluation more information and clinic background is needed. The number of samples is too small to draw any statistical conclusions.</p><p>Comment. Although the control staining was perfect the negative result of CK20 in the cases of diagnosed colon cancer was unexpected. This staining should be performed again to confirm the result. In some cases the number of cells were to few for a certain evaluation. The slides and the results of this work will be archived for further research.</p>
4

Undersökning av affinitet till TS1-218, TS1-2182 och HE1-Q enkelkedjeantikroppar i multicellulära tumörsfäroider cytokeratin 8 för TS1-218, TS1-2182 och HE1-Q enkelkedjeantikroppar i multicellulära tumörsfäroider / Investigation of affinity to cytokeratin 8 in multicellular tumor spheroids for TS1-218, TS1-2182 and HE1-Q single chain variable fragment antibodies

Piercecchi, Marco January 2009 (has links)
In vitro-test för upptäckt och behandling av tumör eller mikrometastaser har de senaste 30 åren gjort stora framsteg tack vare immunokemi och nya framgångsrika cellodlings- tekniker som bättre reproducerar celltillväxt i tre dimensioner (3D) och det omgivande stromat (multicellulär tumörsfäroidodling). TS1-218 scFv (single chain variable fragment) är en monoklonal antikropp som har affinitet till ett protein tillhörande cytoskelettet (cytokeratin). Av TS1-218 har skapats olika varianter (en dimer TS1-2182 och en mutant HE1-Q) med syftet att öka affinitet och retentionstid på platsen för dess verkan. I det här projektet försökte vi att testa och jämföra egenskaper hos alla 3 joderade antikropparna genom att inkubera odlade Hela Hep 2 tumörcellssfäroider med dessa antikroppar. Alla tre antikroppsvarianter visade god förmåga att penetrera sfäroider och att binda deras epitop i cytokeratin 8. Försöken visade att det fanns affinitetsskillnader mellan TS1-218 monomer, dimer och mutant vilket visade sig som olika inbindningsförmåga till sfäroiderna.
5

Biochemical and Immunocytochemical Characterization of Canine Corneal Cells Cultured in Two Different Media

Schorling, Jamie J. 06 June 2007 (has links)
The study purpose was to determine whether canine corneal cultures demonstrate superior growth when cultured in a fully defined epithelial selective medium, Epilife®, compared to Dulbecco's modification of Eagle's medium (DMEM) with fetal bovine serum (FBS), and to characterize cultured canine corneal cells. Superficial keratectomies were performed on three dogs. Samples were trypsinized to separate cell layers. Post-trypsinization, immunohistochemistry confirmed that epithelial cells had been released from the stroma. Both cell populations (presumed epithelial cells and stromal tissues) were cultured in DMEM with FBS or Epilife®. First passage cells were fixed for immunocytochemistry and prepared for PCR. Immunocytochemical staining for pancytokeratin, vimentin, and E-cadherin was evaluated, and immunofluorescence for zonula occludens-1 was attempted. Amplification of cytokeratin 5 (CK5) mRNA was assessed by PCR. Primary presumed epithelial cells grew faster when cultured in DMEM with FBS compared to Epilife®. Stromal tissue segments in Epilife® medium failed to adhere to culture plates, indicating that this medium may inhibit attachment and growth of non-epithelial tissues. Staining of corneal tissue segments confirmed that epithelial layers were pancytokeratin and E-cadherin positive, while stromal cells were vimentin positive. Immunocytochemistry of cultured cells revealed that epithelial cells stained positively for pancytokeratin, vimentin, and E-cadherin, while stromal cells remained only vimentin positive. Greater amplification of CK5 mRNA occurred from epithelial cells grown in Epilife® compared to epithelial cells in DMEM with FBS or the stromal cells. Based on PCR results, Epilife® medium may support retention of the epithelial characteristic of CK5 mRNA expression better than DMEM with FBS. / Master of Science
6

Validation of anti-cytokeratin antibodies used in rapid cancer diagnostics by isoelectric focusing and QCM technology

Kostines, Reneh January 2021 (has links)
Antibodies are Y-shaped proteins. In the human body, antibodies areproduced by plasma cells, mainly T and B cells which are included inthe adaptive immune system. The production of antibodies is stimulatedby antigens. The binding between an antigen-specific antibody and itsantigen can be like the interconnect between a lock and a key.Therefore, antibodies are widely used as diagnostic tools for avariety of diseases but most importantly cancer. Some rapid diagnostictests are completely dependent on the specificity and reactivity ofantibodies such as UBC® Rapid produced by IDL Biotech AB. Therefore,the quality of these antibodies is important. This master thesis at IDL Biotech aimed to validate six anticytokeratinantibodies that are currently used in several rapid cancerdiagnostic tests produced by IDL. Antibody validation is a processwhere specificity, selectivity and reproductivity of an antibody isdemonstrated through specific laboratory investigations. During thisthesis, two laboratory methods were used to validate antibodies,namely, isoelectric focusing electrophoresis and the Attana QuartzCrystal Microbalance based biosensor. Isoelectric focusing electrophoresis (IEF) is a method that determinesproteins pI-values which can then reveal information about posttranslationalmodifications and protein sustainability during storage.IEF revealed changes in pI-values in two antibodies: AB2 and AB4. Attana biosensor analysis on AB1-5 showed that all antibodies havehigh specificity, reactivity and relatively high affinity to theircytokeratin targets. It also revealed that 4 antibodies (AB1 and AB3-5) have lower cross-reactivity with other cytokeratins than theirtarget cytokeratins compared to AB2. Keywords: Antibody validation, Isoelectric focusing, QCM, Attanabiosensor, biosensors, rapid diagnostics, epithelial carcinomas.
7

Fatores reguladores da angiogênese e infiltração tumoral nos carcinomas mamários positivos para a citoqueratina 5 / Regulating factors of angiogênese and tumoral infiltration in positive the mammary carcinomas for citoqueratina 5

Vale, Fabiana Ribeiro do 01 September 2006 (has links)
O reconhecimento de subtipos de carcinomas mamários baseados em suas características moleculares trouxe novas perspectivas na investigação do câncer de mama. Algumas proteínas chaves reguladoras da angiogênese e da infiltração tumoral foram avaliadas em carcinomas de mama de fenótipo basal (CK5+). Foi realizado estudo Imunoistoquímico com 14 anticorpos primários em 100 casos de carcinoma ductal. A positividade para citoqueratina 5 correlacionou-se com indicadores de mau prognóstico, incluindo idade precoce, alto grau histológico, linfonodos positivos, estádio patológico avançado, negatividade para receptores hormonais, e uma alta taxa de proliferação celular, avaliado pelo Ki67. A positividade para a CK5 também se correlacionou com a expressão do VEGF, mas não com a densidade da microvascularização. Considerando que a superexpressão de VEGF pelas células neoplásicas da mama leva a um aumento da atividade proliferativa in vitro independente de seu efeito angiogênico, a expressão diferencial do VEFG pode contribuir para o comportamento mais agressivo da neoplasia. Houve correlação do CK5 com TIMP1, mas não com MMP1, MMP2, EMMPRIN, TIMP2 and PAI, indicando que o estimulo antiproteolítico pode ser preponderante nesta neoplasia. / The recognition of subtypes of breast carcinomas based on their molecular features has brought new perspectives in breast cancer investigation. Some key regulators of angiogenesis and tumor infiltration were evaluated in breast carcinomas of basal-phenotype (CK5+). Immunohistochemistry with 14 primary antibodies was performed in 100 formalin-fixed paraffin-embedded samples of invasive ductal carcinomas. Cytokeratin 5 correlated with indicators of poor outcome, including precocious age, high histological grade, lymph node positivity, advanced pathological stage, negativity for hormonal receptors, and a high proliferative rate (Ki67 labeled index). CK5 also correlated with VEGF expression but not with the microvessel density. Considering that VEGF overexpressing neoplastic mammary cells display increased proliferative activity in vitro regardless its angiogenic effect, the differential expression of VEGF may contribute for the more aggressive behavior of these neoplasms. CK5 correlated with TIMP1, but not MMP1, MMP2, EMMPRIN, TIMP2 and PAI, indicating that anti-proteolytic stimuli may be preponderant in these neoplasms.
8

Interação Trypanosoma cruzi-célula hospedeira: estudo do \"domínio FLY\", motivo carboxi-subterminal conservado na superfamília das gp85/trans-sialidases. / Interaction between Trypanosoma cruzi and host cell: study of FLY domain, a conserved carboxil-subterminal motiv of gp85/trans-sialidases.

Fessel, Melissa Regina 24 November 2006 (has links)
Trypanosoma cruzi, agente causador da Doença de Chagas, é um protozoário intracelular obrigatório. Vários estudos foram realizados visando a caracterização de moléculas de 85-90 kDa, presentes na superfície do parasita bem como de seus possíveis receptores nas células do hospedeiro vertebrado. Um membro da superfamília das gp85/trans-sialidases (Tc85-11), expresso somente na superfície das formas intectivas tripomastigotas e que adere em laminina e em células, foi clonado e caracterizado em nosso laboratório. Peptídeo J, fragmento de Tc85-11 não implicado em adesão a laminina, que contém o motivo conservado na superfamília, com seqüência VTVXNVFLYNR, aqui denominado \"domínio FLY\", foi identificado como sendo responsável pela adesão da porção carboxi-terminal da proteína em células epiteliais e, adicionado ao meio de cultura, promoveu aumento do número de células infectadas por T.cruzi. Seu receptor foi descrito como CK18 (Magdesian et al., 2001). Dando continuidade a esse estudo, em nosso laboratório caracterizamos a porção amino-terminal de CK18 como a região da interação com \"domínio FLY\" e identificamos o provável sítio de ligação, localizado entre os 15 aminoácidos iniciais da proteína. Adicionalmente, com o intuito de determinar a função do \"domínio FLY\", caracterizamos o peptídeo J como molécula extremamente adesiva, interagindo com a superfície de células epiteliais, matriz extracelular e promovendo interação entre tripomastigotas e ECM, possivelmente por meio de interações hidrofóbicas não dependentes de sua estrutura tridimensional adotada na proteína nativa. \"Domínio FLY\" foi caracterizado, ainda, como possível modulador da infecção por tripomastigotas já que, da mesma forma que estimula a invasão quando adicionado ao meio de cultura (Magdesian et al., 2001), promove secreção de proteínas imunorelacionadas com CK18 e ligantes de proteína A para o sobrenadante celular. Esse sobrenadante é capaz de in vitro inibir o processo infectivo do parasita em cerca de 40%. / Trypanosoma cruzi the causative agent of Chagas´ disease is an obligatory intracellular parasite in the mammalian host. Altrough the mechanism of trypomastigotes invasion of host cells has been intensively studied, a final and integrate picture of the process remains elusive. Members of the gp85/trans-sialidase superfamily have been implicated in the parasite-host interaction, with Tc85 family (85 kDa glycoproteins) implicated in the adhesion step. Our laboratory showed that Tc85-11, one member of Tc85 family, is a multi-adhesive molecule, with binding sites located at the amino- and carboxi-portions of the protein. The conserved \"FLY domain\" (peptide J) is present in all members of the family, binds to cytokeratin 18 (CK18) and enhances T. cruzi invasion (Magdesian et al., 2001). Herein, we localized the binding site of \"FLY domain\" on the amino-portion of CK18 and demonstrated an increase of trypomastigotes adhesion to extracellular matrix upon FLY treatment. The \"FLY domain\" can modulate T. cruzi infection in vitro and apparently is responsible for inducing the secretion of molecules by the host that inhibit trypomastigote invasion.
9

Fatores hepatotróficos modulam a capacidade proliferativa em cultura primária de hepatócitos de ratos normais / Hepatotrophic factors modulate the proliferative potential in primary hepatocyte cultures of normal rats

Bösch, Rosemary Viola 25 February 2010 (has links)
A utilização de fatores hepatotróficos (FH) tem trazido importantes avanços no tratamento de algumas doenças hepáticas. A avaliação dos efeitos dessas substâncias pode ser feita com o uso de modelos in vivo, como a regeneração hepática após a hepatectomia parcial ou in vitro, como a cultura de hepatócitos, células estreladas ou outros tipos celulares do fígado. O modelo de cultura demonstra ser útil por possibilitar a análise individualizada de determinadas substâncias ou soluções diretamente nas células-alvo, facilitando o delineamento de seu mecanismo de ação. Dessa forma, o presente trabalho estudou in vitro os efeitos da administração de fatores hepatotróficos (FH) em hepatócitos isolados de fígados de ratos, avaliando seu metabolismo e proliferação celular. Trinta ratos Wistar fêmeas foram utilizados, o fígado retirado e, por digestão enzimática in situ, suas células foram dissociadas e os hepatócitos separados em gradiente de Percoll 45%; cultivados em meio DMEM/F12, tratadas com diferentes concentrações dos FH (1X, 5X e 10X) e analisadas em intervalos de 24, 48 e 72 horas. A viabilidade e a proliferação celular foram avaliadas pelo método colorimétrico MTT, a toxicidade pelo iodeto de propídeo, o potencial elétrico da membrana mitocondrial pela Rodamina 123 e a expressão da citoqueratina 8, 18 e desmina como marcadores do citoesqueleto. O metabolismo hepático foi avaliado pela depuração do verde de indocianina (VIC), pela quantificação de colágeno tipo I e pela formação de radicais lipídicos poliinsaturados peroxidados. A técnica utilizada para a obtenção de hepatócitos mostrou-se eficaz com viabilidade superior a 90%, sem apresentar toxicidade, com manutenção do potencial mitocondrial e com marcação positiva para citoqueratinas 8, 18 e desmina. A adição dos FH aumentou a proliferação dos hepatócitos nos três períodos analisados em relação ao grupo controle. Os FH não demonstraram toxicidade em cultura primária de hepatócitos em nenhuma das concentrações avaliadas ao longo de todos os períodos experimentais. A adição dos FH na concentração de 10X evitou a formação de radicais livres, protegendo os hepatócitos da lipoperoxidação. Por outro lado, a avaliação funcional das culturas primárias pelo teste VIC mostrou-se eficaz na determinação do metabolismo dos hepatócitos, como a manutenção dos níveis das transaminases e amilase. Os hepatócitos mantidos em cultura primária após a adição dos FH em todos os períodos analisados aumentaram a produção de colágeno, e também foram capazes de modificar a distribuição da população de células nas fases quiescentes, aumentando sua capacidade de síntese. A adição dos FH nas concentrações estudadas nas culturas de hepatócitos mostrou-se eficaz na manutenção dessas células, mantendo-se funcionalmente ativos, com a expressão dos marcadores de seu metabolismo e diferenciação. / The use of hepatrotophic hic factors (HF) has provided important advances in the treatment of several hepatic disorders. The evaluation of this treatment may be carried out by in vivo models, as experiments on hepatic regeneration after partial hepatectomy; or in vitro models as culture of hepatocytes, stellate cells or any other hepatic cell. This last model allows an individual analysis of the studied substances on their target cells, providing the possibility of further investigation on the mechanisms involved. Therefore, the present study evaluated the in vitro effects of the hepatotrophic factors administration on the metabolism and proliferation of cultured hepatocytes from normal rat liver. Liver from 30 Wistar rats were used, and after in situ enzimatic dissociation, hepatocytes were collected and separated by 45% Percoll density gradient, cultivated in DMEN/F12 media supplemented with different HF concentrations (1×, 5× and 10×) and finally analyzed at 24, 48 and 72hs intervals. Cell viability and proliferation were assessed by MTT colorimetric assay, cell toxicity by propidium iodide, mitochondrial membrane electrical potential by 123 rodamine test and cytokeratin 8, 18 and desmin as cytoskeleton markers. Hepatic metabolism was evaluated by infusion of indocianine green (ICG), by type I collagen quantification and by peroxided polyunsaturated lipid radicals production. The techniques used in order to collect hepatocytes proved to be efficient, with a viability higher than 90%, no toxicity, and the maintenance of the mitochondrial membrane potential and positive labeling for cytokeratins (CK) 8, 18 and desmin. The HF addition increased the proliferation of hepatocytes in the three periods analyzed, when compared to the control group. The HF did not show any toxicity in primary hepatocytes culture regardless of the concentration evaluated along the experimental periods. The HF addition impaired the production of free radicals, protecting the hepatocytes from the lipid peroxidation. On the other hand, the functional evaluation of primary hepatocytes cultures using the ICG test proved to be efficient in the determination of the hepatocytes metabolism, as the maintenance of the transaminase and amylase levels. The hepatocytes kept in primary culture after HF addition in all the analyzed periods increased the collagen production and were also able to shift the distribution of quiescent cells population of, thus increasing their synthesis capacity. The HF addition in the studied concentrations in hepatocytes cultures proved to be efficient in the maintenance of these cells, that remain functionally active and expressing their metabolism and differentiation characteristic markers.
10

Fatores reguladores da angiogênese e infiltração tumoral nos carcinomas mamários positivos para a citoqueratina 5 / Regulating factors of angiogênese and tumoral infiltration in positive the mammary carcinomas for citoqueratina 5

Fabiana Ribeiro do Vale 01 September 2006 (has links)
O reconhecimento de subtipos de carcinomas mamários baseados em suas características moleculares trouxe novas perspectivas na investigação do câncer de mama. Algumas proteínas chaves reguladoras da angiogênese e da infiltração tumoral foram avaliadas em carcinomas de mama de fenótipo basal (CK5+). Foi realizado estudo Imunoistoquímico com 14 anticorpos primários em 100 casos de carcinoma ductal. A positividade para citoqueratina 5 correlacionou-se com indicadores de mau prognóstico, incluindo idade precoce, alto grau histológico, linfonodos positivos, estádio patológico avançado, negatividade para receptores hormonais, e uma alta taxa de proliferação celular, avaliado pelo Ki67. A positividade para a CK5 também se correlacionou com a expressão do VEGF, mas não com a densidade da microvascularização. Considerando que a superexpressão de VEGF pelas células neoplásicas da mama leva a um aumento da atividade proliferativa in vitro independente de seu efeito angiogênico, a expressão diferencial do VEFG pode contribuir para o comportamento mais agressivo da neoplasia. Houve correlação do CK5 com TIMP1, mas não com MMP1, MMP2, EMMPRIN, TIMP2 and PAI, indicando que o estimulo antiproteolítico pode ser preponderante nesta neoplasia. / The recognition of subtypes of breast carcinomas based on their molecular features has brought new perspectives in breast cancer investigation. Some key regulators of angiogenesis and tumor infiltration were evaluated in breast carcinomas of basal-phenotype (CK5+). Immunohistochemistry with 14 primary antibodies was performed in 100 formalin-fixed paraffin-embedded samples of invasive ductal carcinomas. Cytokeratin 5 correlated with indicators of poor outcome, including precocious age, high histological grade, lymph node positivity, advanced pathological stage, negativity for hormonal receptors, and a high proliferative rate (Ki67 labeled index). CK5 also correlated with VEGF expression but not with the microvessel density. Considering that VEGF overexpressing neoplastic mammary cells display increased proliferative activity in vitro regardless its angiogenic effect, the differential expression of VEGF may contribute for the more aggressive behavior of these neoplasms. CK5 correlated with TIMP1, but not MMP1, MMP2, EMMPRIN, TIMP2 and PAI, indicating that anti-proteolytic stimuli may be preponderant in these neoplasms.

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