No description available.

No description available.

Spinal cord injuries result in permanent loss of motor function, leaving those affected with long term physical and financial burdens. Strategies for spinal cord injury repair must overcome unique challenges due to scar tissue that seals off the injury site, preventing regeneration. Tissue engineering can address these challenges with scaffolds that serve as cell- and drug-delivery tools, replacing damaged tissue while simultaneously addressing the inhibitory environment on a biochemical level. To advance this approach, the choice of cells, biomaterial matrix, and drug delivery system must be investigated and evaluated. This research seeks to evaluate (1) the behaviour of murine induced pluripotent stem cells in previously characterized 3D fibrin matrices; (2) the 3D fibrin matrix as a platform to support the differentiation of human induced pluripotent stem cells; and (3) the ability of an affinity-based drug delivery system to control the release of emerging spinal cord injury therapeutic, heat shock protein 70 from fibrin scaffolds. / Graduate / 0541 / amy.lynn.montgomery@gmail.com

Human Epidermal Growth Factor Receptor 2 (HER-2/neu) is a breast tumor antigen (Ag) commonly overexpressed in 30% of breast cancer cases. Both HER-2/neu-targeted DNA-based and transgene modified dendritic cell (DC)-based vaccines are potent elements in eliciting HER-2/neu specific antitumor immune responses; however, there has been no side-by-side comparison of these two different immunization methods. We utilized an in vivo murine tumor model expressing the rat neu Ag to compare the immunization efficacy between DC transduced with replication-deficient adenovirus containing neu (AdVneu), to form DCneu, and plasmid DNA (pcDNA) vaccine. DCneu displayed an upregulation of immunologically important molecules and inflammatory cytokines expression such as IL-6 that partially mediated conversion of the regulatory T (Tr) cell suppression. Wildtype FVB/N mice immunized with DCneu induced stronger HER-2/neu-specific humoral and cellular immune responses compared to plasmid DNA immunized mice. Furthermore, mice immunized with DCneu remained completely protected from tumor challenge compared to partial or no protection observed in DNA immunized mice in two tumor animal models. In FVBneuN transgenic mice, which develop spontaneous breast tumors at 4-8 months of age, DCneu significantly delayed tumor onset when immunization conducted in mice at a younger age. Taken together, we demonstrated that a HER-2/neu-gene modified DC vaccine is more potent than a plasmid DNA vaccine in inducing neu specific immune responses resulting in greater protective and preventative effects in the tumor models examined. <p>In another study, we examined the use of a DC-based cancer vaccine involving the phagocytosis of apoptotic tumor cells expressing heat shock protein 70 (HSP70). The dual role of HSP70, as an antigenic peptide chaperone and danger signal, makes it especially important in DC-based vaccination. In this study, we investigated the impacts of apoptotic transgenic MCA/HSP tumor cells expressing HSP70 on DC maturation, T cell stimulation and overall vaccine efficacy. We found that DC with phagocytosis of MCA/HSP in the early phase of apoptosis expressed more peptide-major histocompatibility class (pMHC) I complexes, stimulated stronger cytotoxic T lymphocytes (CTL) responses and induced greater immune protection against MCA tumor cell challenge, compared to mice immunized with DC that phagocytosed MCA/HSP cells in the late phase of apoptosis. Taken together, our data demonstrated that HSP70 expression on apoptotic tumor cells stimulated DC maturation and DC with phagocytosis of apoptotic tumor cells expressing HSP70 in early phase of apoptosis more efficiently induced tumor-specific CTL responses and immunity than DC with phagocytosis of apoptotic tumor cells in late phase of apoptosis. <p>Overall, we have examined variations in designing DC-based cancer vaccines in two completely different model systems. Taken together, our results may have an important impact in designing DC-based antitumor vaccines.

Human Epidermal Growth Factor Receptor 2 (HER-2/neu) is a breast tumor antigen (Ag) commonly overexpressed in 30% of breast cancer cases. Both HER-2/neu-targeted DNA-based and transgene modified dendritic cell (DC)-based vaccines are potent elements in eliciting HER-2/neu specific antitumor immune responses; however, there has been no side-by-side comparison of these two different immunization methods. We utilized an in vivo murine tumor model expressing the rat neu Ag to compare the immunization efficacy between DC transduced with replication-deficient adenovirus containing neu (AdVneu), to form DCneu, and plasmid DNA (pcDNA) vaccine. DCneu displayed an upregulation of immunologically important molecules and inflammatory cytokines expression such as IL-6 that partially mediated conversion of the regulatory T (Tr) cell suppression. Wildtype FVB/N mice immunized with DCneu induced stronger HER-2/neu-specific humoral and cellular immune responses compared to plasmid DNA immunized mice. Furthermore, mice immunized with DCneu remained completely protected from tumor challenge compared to partial or no protection observed in DNA immunized mice in two tumor animal models. In FVBneuN transgenic mice, which develop spontaneous breast tumors at 4-8 months of age, DCneu significantly delayed tumor onset when immunization conducted in mice at a younger age. Taken together, we demonstrated that a HER-2/neu-gene modified DC vaccine is more potent than a plasmid DNA vaccine in inducing neu specific immune responses resulting in greater protective and preventative effects in the tumor models examined. <p>In another study, we examined the use of a DC-based cancer vaccine involving the phagocytosis of apoptotic tumor cells expressing heat shock protein 70 (HSP70). The dual role of HSP70, as an antigenic peptide chaperone and danger signal, makes it especially important in DC-based vaccination. In this study, we investigated the impacts of apoptotic transgenic MCA/HSP tumor cells expressing HSP70 on DC maturation, T cell stimulation and overall vaccine efficacy. We found that DC with phagocytosis of MCA/HSP in the early phase of apoptosis expressed more peptide-major histocompatibility class (pMHC) I complexes, stimulated stronger cytotoxic T lymphocytes (CTL) responses and induced greater immune protection against MCA tumor cell challenge, compared to mice immunized with DC that phagocytosed MCA/HSP cells in the late phase of apoptosis. Taken together, our data demonstrated that HSP70 expression on apoptotic tumor cells stimulated DC maturation and DC with phagocytosis of apoptotic tumor cells expressing HSP70 in early phase of apoptosis more efficiently induced tumor-specific CTL responses and immunity than DC with phagocytosis of apoptotic tumor cells in late phase of apoptosis. <p>Overall, we have examined variations in designing DC-based cancer vaccines in two completely different model systems. Taken together, our results may have an important impact in designing DC-based antitumor vaccines.

Spinal cord injuries result in permanent loss of motor function, leaving those affected with long term physical and financial burdens. Strategies for spinal cord injury repair must overcome unique challenges due to scar tissue that seals off the injury site, preventing regeneration. Tissue engineering can address these challenges with scaffolds that serve as cell- and drug-delivery tools, replacing damaged tissue while simultaneously addressing the inhibitory environment on a biochemical level. To advance this approach, the choice of cells, biomaterial matrix, and drug delivery system must be investigated and evaluated. This research seeks to evaluate (1) the behaviour of murine induced pluripotent stem cells in previously characterized 3D fibrin matrices; (2) the 3D fibrin matrix as a platform to support the differentiation of human induced pluripotent stem cells; and (3) the ability of an affinity-based drug delivery system to control the release of emerging spinal cord injury therapeutic, heat shock protein 70 from fibrin scaffolds. / Graduate / 0541 / amy.lynn.montgomery@gmail.com

O ψευδάργυρος -Zn ελέγχει τον μεταβολισμό των λιπιδίων και γλυκόζης μέσω Ζn-μεταγραφικών παραγόντων. Δίαιτες υψηλών λιπαρών οδηγούν στην ενδοκυτταρική συσσώρευση ελευθέρων ριζών, μειώνουν την μεταγραφική έκφραση των εκκαθαριστών τους και την ενεργότητα αντιοξειδωτικών ενζύμων και οδηγούν σε μεταβολικό σύνδρομο. Οι πρωτεϊνες του θερμικού shock (Heat shock proteins-HSP) παίζουν σημαντικό ρόλο στην αντίσταση στο κυτταρικό stress ως προσαρμογή ,μετά από έκθεση, σε διάφορα ερεθίσματα. ΣΚΟΠΟΣ : Μελέτη της επίδρασης του διατροφικού Ζn και των Hsp70,στην μεταβονομική των λιπιδίων αίματος και ήπατος ποντικών ΥΛΙΚΟ-ΜΕΘΟΔΟΙ :Ενήλικα αρσενικά ποντίκια: 1. Wild type (Wt) Hybrid (F1/F1) C57Bl/6 x CBA και 2. Transgenic (Tg) human HSP70 overexpressing mice, από ηλικίας ενός μηνός εντάχθηκαν στις παρακάτω διατροφές ,επί 10 εβδομάδες. Διατροφή Αριθμός Wt Αριθμός Tg Chow Diet (30 Zn) 6 10 High Fat Diet (3 Zn) 13 12 High Fat Diet (30 Zn) 9 8 High Fat Diet (300 Zn) 12 12 Σύνθεση των τριών διαιτών υψηλών λιπαρών -HFD: 3mg, 30mg, 300mg Zn /kg τροφής (mucedoola s.r.l Ιtaly-55% Cal από λιπαρά στοιχεία), Chow : δίαιτα ελέγχου Βιοχημικές αναλύσεις: Cholesterol ,Triglycerides ,HDL-cholesterol, Glucose ,Insulin Μετρήσεις μετάλλων και αντιοξειδωτικών παραγόντων: SOD (ερυθρά αιμοσφαίρια ) TAC (ορός αίματος) Zn , Cu (ερυθρά αιμοσφαίρια και ιστός ήπατος) Μεταβονομική ανάλυση και αξιολόγηση λιπιδίων :Εκχύλιση ορού αίματος και ηπατικού ιστού για λήψη Φάσματος 1H-NMR ΣΥΜΠΕΡΑΣΜΑΤΑ 1. Η HF δίαιτα αύξησε σημαντικά ,το τελικό βάρος και τον ρυθμό αύξησης βάρους ,τη χοληστερόλη -CL και την λιποπρωτεϊνη υψηλής πυκνότητας-ΗDL ,την ινσουλίνη –Ins, στα WT & Tg και μείωσε την ολική αντιοξειδωτική ικανότητα-TAC στο πλάσμα και την δραστηριότητα της σουπεροξείδιο-δισμουτάσης-SOD στα ερυθροκύταρα των WΤ και Tg 2. Ο επαρκής διατροφικός Zn (30mg/kgτροφής) φαίνεται να αποτελεί κρίσιμο παράγοντα διαμόρφωσης προστατευτικού ηπατολιπιδαιμικού προφίλ, ποντικών σε υπερλιπιδική δίαιτα. Η αύξηση ή μείωση του Zn σε HFDς φαίνεται να μειώνει την TAC του πλάσματος σε WΤ και Tg ενώ η δραστικότητα της SOD φαίνεται ανάλογη των επιπέδων του Zn Η ανεπάρκεια ή περίσσεια Zn αυξάνει τα αθηρογόνα SFA και μειώνει τα αντι-αθηρογόνα λιπίδια, PC, DU, LA DIAL ,UFA στις HDL, nonHDL και το ήπαρ, στα WΤHFD και στα ΤgHFD 3. Οι HSP70 : Τα διαγονιδιακά ζώα που φέρουν το γονίδιο hHsp70, φαίνεται ότι είτε σε έλλειψη είτε σε περίσσεια Ζn, που συνήθως συνοδεύoνται από μεταβολικό σύνδρομο, κατορθώνουν να διατηρούν καλλίτερους δείκτες λιπιδικού προφίλ σε σχέση με τα WT ζώα. Τα Τg εμφάνισαν σημαντικά χαμηλότερη CL ,TG , HDL σε σύγκριση με τα WT ενώ η HSP70 αύξησε σημαντικά την ενεργότητα της ολικής SOD στα ερυθρά αιμοσφαίρια. Η HSP70 μείωσε τα αθηρογόνα SFA και αύξησε τα αντιαθηρογόνα λιπίδια DIAL, DU, LA, UFA, SM στις HDL, nonHDL , και στο ήπαρ ποντικών που εκτέθηκαν σε HFD και σε όλες τις συγκεντρώσεις Zn. / Zinc –Zn controls lipid and glucose metabolism via Zn-transcription factors. High fat diets –HFDs lead to intracellular free radicals accumulation, decrease the transcriptional expression of their scavengers and anti-oxidative enzymes’ activity leading finally to metabolic syndrome. Heat shock proteins-HSPs play a significant role in cellular resistance response , as an adaptation mechanism, after exposure to various stimuli. SCOPE: To study the effects of nutritional Zn and HSP70s on the metabonomics of serum and liver lipids in mice MATERIALS-METHODS: Male mice: 1. Wild type (Wt) Hybrid (F1/F1) C57Bl/6 x CBA και 2. Transgenic (Tg) human HSP70 overexpressing mice, one month old, were subjected for 10 weeks to the following diets : Diet Number of Wt Number of Tg Chow Diet (30 Zn) 6 10 High Fat Diet (3 Zn) 13 12 High Fat Diet (30 Zn) 9 8 High Fat Diet (300 Zn) 12 12 Composition of the three HF Diets: 3mg, 30mg, 300mg Zn /kg τροφής (mucedoola s.r.l Ιtaly-55% Cal from greasy ingredients),Chow :control diet Biochemical analyses: Cholesterol ,Triglycerides ,HDL-cholesterol, Glucose ,Insulin Metals and antioxidative factors levels: SOD (red blood cells )TAC (blood serum) Zn , Cu (red blood cells and liver tissue) Lipids metabonomics : Blood serum and liver tissue extracts for 1H-NMR spectrum analysis and evaluation CONCLUSIONS 1. HFDiet significantly increased the rate of mice body weight gaining, as well as, cholesterol-CL, high density lipoproteins-HDL, insulin, in WT and Tg mice and decreased plasma total antioxidant capacity-TAC and red blood cell super oxide dismutase –SOD activity , in WT and Tg mice 2.Suficient nutritional Zn (30 mg/kg food) prevails as a crucial modulator of a protective hepato-lipidaemic profil of mice in high fat diet. Zinc deficiency or excessiveness , in HFDiets , decreases plasma TAC in WT and Tg mice, while SOD activity shows proportional to Zn levels. Zinc deficiency or excessiveness increases the atherogenic SFA and decreases the anti –atherogenic lipids : PC, DU, LA DIAL ,UFA, in HDL, nonHDL and liver, in WΤ-HFD and Τg-HFD mice 3. HSP70s : Transgenic mice over-expressing hHsp70 gene and exposed either to Zn deficiency or Zn excessiveness , both driving usually to metabolic syndrome , reveal significantly better lipid profile indicators, comparing to WT mice. Tg mice revealed significantly lower CL , TG , HDL levels compared to WT, while HSP70 in Τg mice significantly increased total SOD activity in red blood cells. HSP70 also decreased the atherogenic SFAs and increased the anti-atherogenic lipids DIAL, DU, LA, UFA, SM in HDL, nonHDL and in the liver of mice exposed to HFDiets and all Zn concentrations

Orientador: Aureo Tatsumi Yamada / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T22:06:48Z (GMT). No. of bitstreams: 1 Lima_PatriciaDanieleAzevedo_M.pdf: 2003445 bytes, checksum: 597310400704b8df5b1e07544bd6caca (MD5) Previous issue date: 2008 / Resumo: Durante a gestação em animais que possuem placentação hemocorial, a hipóxia no primeiro terço da prenhez é um dos fatores cruciais para indução da angiogênese e o adequado desenvolvimento da placenta. Contudo, esta hipóxia se contrapõe à intensa atividade das células que requerem elevado metabolismo, gerando um estresse fisiológico para estas células presentes na interface materno-fetal. Presume-se que estas células necessitem de mecanismos apropriados de citoproteção para sua sobrevida enquanto comprometidos ativamente no suporte funcional do útero gestante. Neste sentido, o presente trabalho teve como objetivo investigar a expressão e a distribuição da proteína de choque térmico 70 (HSP70) na interface materno-fetal durante a gestação normal em camundongos e a sua possível variação em condição de estresse adicional induzido experimentalmente através da lesão embrionária. Sítios de desenvolvimento embrionário/fetal de camundongos prenhes do dia de gestação (dg) 6 ao 17 e, após 30 minutos, 1, 6 e 12 h dos animais submetidos à lesão cirúrgida do embrião (LCE) no dg 9 foram coletados para: - processamento histotécnico convencional de embebição em parafina destinados às análises citoquímicas (lectina DBA e reação de TUNEL) e imunocitoquímicas (anti-HSP72/73, anti-PCNA); - embebição em resina Lowilcryl- K4M para imunocitoquímica ultraestrutural (anti-HSP72/73); - obtenção de homogenados teciduais destinados à SDS-PAGE das frações protéicas e Westernblot (anti-HSP72/73) e, - extração de RNA de homogenados teciduais e de células uNK isoladas para análise de transcritos (HSP72 e 73) com amplificação pelo RTPCR. As análises imunocitoquímicas demonstraram que as células uNK eram as únicas células que expressavam de forma constante as isoformas HSP72/73 ao longo da gestação, sendo confirmada a expressão dos transcritos gênicos das isoformas HSP72/73 nas células uNK isoladas pelo RT-PCR. A imunomicroscopia eletrônica detectou marcação conspícua nas mitocôndrias das células uNK. A análise quantitativa demonstrou que a lesão do embrião reduz o número de células uNK positivas para HSP72/73 e, o SDS/PAGE/Western-blotting identificou as isoformas HSP72 e 73 presente nos homogenados teciduais do útero com uma perceptível redução na intensidade da banda correspondente ao HSP73 nas amostras de pós-lesão, sem afetar significativamente a isoforma HSP72. As análises realizadas com a dupla marcação de TUNEL e PCNA demonstrarm redução de células uNK PCNA positivas no útero submetido a lesão embrionária e aumento de núcleos marcadas positivamente pelo TUNEL. Estes resultados demonstram de forma inédita a expressão de HSP72/73 nas células uNK, sendo inédita também a constatação em leucócitos, sugerindo um papel citoprotetor para estas células importantes na manutenção da gestação. A redução de células uNK HSP72/73 positivas no útero gestante desencadeada pela lesão embrionária, consubstancia a hipótese da atuação da HSP 72/73 como chaperona citoprotetora nas células uNK sendo crítica a atuação da isoforma HSP73 presente na mitocôndria através da regulação negativa das vias de morte celular por apoptose nas células uNK / Resumo: Durante a gestação em animais que possuem placentação hemocorial, a hipóxia no primeiro terço da prenhez é um dos fatores cruciais para indução da angiogênese e o adequado desenvolvimento da placenta. Contudo, esta hipóxia se contrapõe à intensa atividade das células que requerem elevado metabolismo, gerando um estresse fisiológico para estas células presentes na interface materno-fetal. Presume-se que estas células necessitem de mecanismos apropriados de citoproteção para sua sobrevida enquanto comprometidos ativamente no suporte funcional do útero gestante. Neste sentido, o presente trabalho teve como objetivo investigar a expressão e a distribuição da proteína de choque térmico 70 (HSP70) na interface materno-fetal durante a gestação normal em camundongos e a sua possível variação em condição de estresse adicional induzido experimentalmente através da lesão embrionária. Sítios de desenvolvimento embrionário/fetal de camundongos prenhes do dia de gestação (dg) 6 ao 17 e, após 30 minutos, 1, 6 e 12 h dos animais submetidos à lesão cirúrgida do embrião (LCE) no dg 9 foram coletados para: - processamento histotécnico convencional de embebição em parafina destinados às análises citoquímicas (lectina DBA e reação de TUNEL) e imunocitoquímicas (anti-HSP72/73, anti-PCNA); - embebição em resina Lowilcryl- K4M para imunocitoquímica ultraestrutural (anti-HSP72/73); - obtenção de homogenados teciduais destinados à SDS-PAGE das frações protéicas e Westernblot (anti-HSP72/73) e, - extração de RNA de homogenados teciduais e de células uNK isoladas para análise de transcritos (HSP72 e 73) com amplificação pelo RTPCR. As análises imunocitoquímicas demonstraram que as células uNK eram as únicas células que expressavam de forma constante as isoformas HSP72/73 ao longo da gestação, sendo confirmada a expressão dos transcritos gênicos das isoformas HSP72/73 nas células uNK isoladas pelo RT-PCR. A imunomicroscopia eletrônica detectou marcação conspícua nas mitocôndrias das células uNK. A análise quantitativa demonstrou que a lesão do embrião reduz o número de células uNK positivas para HSP72/73 e, o SDS/PAGE/Western-blotting identificou as isoformas HSP72 e 73 presente nos homogenados teciduais do útero com uma perceptível redução na intensidade da banda correspondente ao HSP73 nas amostras de pós-lesão, sem afetar significativamente a isoforma HSP72. As análises realizadas com a dupla marcação de TUNEL e PCNA demonstrarm redução de células uNK PCNA positivas no útero submetido a lesão embrionária e aumento de núcleos marcadas positivamente pelo TUNEL. Estes resultados demonstram de forma inédita a expressão de HSP72/73 nas células uNK, sendo inédita também a constatação em leucócitos, sugerindo um papel citoprotetor para estas células importantes na manutenção da gestação. A redução de células uNK HSP72/73 positivas no útero gestante desencadeada pela lesão embrionária, consubstancia a hipótese da atuação da HSP 72/73 como chaperona citoprotetora nas células uNK sendo crítica a atuação da isoforma HSP73 presente na mitocôndria através da regulação negativa das vias de morte celular por apoptose nas células uNK / Abstract: During the pregnancy of animals developing hemochorial placenta, the hypoxia in the first third of pregnancy is one of the crucial factor for induction of angiogenesis and adequate placental development. However, this hypoxia is contradictory to the great dynamism and metabolism of cells required in the pregnant uterus, conditioning a physiological stress for the cells present at the maternal-fetal interface. It is presumed these cells demand appropriate cytoprotective mechanism for their survival while are committed to actively support the pregnancy. In this way, the present work aimed to investigate the expression and distribution of the chapelone isoforms heat shock protein 72 and 73 (HSP72/73) at the maternal fetal-interface through the pregnancy in mice and its possible variations under additional stressing condition induced experimentally by embryo lesion. Embryo/fetus developing sites of pregnant mice from gestational days (gd) 6 to 17 and, after 30min, 1h and 6h of surgical embryo lesion (SEL) on gd 9 mice, were collected for: - conventional paraffin embedding for cytochemical (DBA lectin and TUNEL reaction) and immunocytochemical (anti-HSP72/73, anti-PCNA) analysis; - LR-white resin embedding for ultrastructural immunocytochemistry (anti- HSP72/73); - uterine tissue homogenates for SDS-PAGE of proteins fractions and Western-blot (anti-HSP7273) and; - RNA extratction form uterine tissue homogenates and isolated uNK cells for transcripts (HSP72 and 73) amplification by RT-PCR. The immunocytcchemical analysis showed the uNK cells as the only cell expressing constantly the HSP72/73 isoforms throughout the gestation, being confirmed the expression of both gene isoforms by RT-PCR in uNK cells. The immunoelectron microscopy detected conspicuous labeling in the mitochondria of uNK cells. The quantitative analysis demonstrated that embryo-lesion reduced the number of HSP72/73 positive uNK cells in the uterus and, SDS/PAGE and Westernblot identified the HSP72 and 73 isoforms present in the tissue homogenates with low reactive intensity of the band corresponding to HSP73 in the after-lesion samples, without affecting significantly the HSP72 isoform. The analysis of TUNEL and PCNA double labelling showed decreasing of PCNA positive-uNK cells in the uterus after embryo-lesion and increasing of TUNEL positive nuclei. These results confirms the expression of HSP72 and HSP73 isoforms in the uNK cells through the gestation and to date, this is also the first report showing HSP70 in leukocytes, suggesting a cytoptotective function to this cell while working actively as important cells supporting the pregnancy. The decreasing of HSP72/73 positive uNK cells in the pregnant uterus triggered by embryo lesion consubstantiate the hypothesis of HSP72/73 working as cytoprotective chaperone in the uNK cells, and the HSP73 isoform in the mitochondria seems to be critical on down-regulation of apoptotic cell depth pathway / Abstract: During the pregnancy of animals developing hemochorial placenta, the hypoxia in the first third of pregnancy is one of the crucial factor for induction of angiogenesis and adequate placental development. However, this hypoxia is contradictory to the great dynamism and metabolism of cells required in the pregnant uterus, conditioning a physiological stress for the cells present at the maternal-fetal interface. It is presumed these cells demand appropriate cytoprotective mechanism for their survival while are committed to actively support the pregnancy. In this way, the present work aimed to investigate the expression and distribution of the chapelone isoforms heat shock protein 72 and 73 (HSP72/73) at the maternal fetal-interface through the pregnancy in mice and its possible variations under additional stressing condition induced experimentally by embryo lesion. Embryo/fetus developing sites of pregnant mice from gestational days (gd) 6 to 17 and, after 30min, 1h and 6h of surgical embryo lesion (SEL) on gd 9 mice, were collected for: - conventional paraffin embedding for cytochemical (DBA lectin and TUNEL reaction) and immunocytochemical (anti-HSP72/73, anti-PCNA) analysis; - LR-white resin embedding for ultrastructural immunocytochemistry (anti- HSP72/73); - uterine tissue homogenates for SDS-PAGE of proteins fractions and Western-blot (anti-HSP7273) and; - RNA extratction form uterine tissue homogenates and isolated uNK cells for transcripts (HSP72 and 73) amplification by RT-PCR. The immunocytcchemical analysis showed the uNK cells as the only cell expressing constantly the HSP72/73 isoforms throughout the gestation, being confirmed the expression of both gene isoforms by RT-PCR in uNK cells. The immunoelectron microscopy detected conspicuous labeling in the mitochondria of uNK cells. The quantitative analysis demonstrated that embryo-lesion reduced the number of HSP72/73 positive uNK cells in the uterus and, SDS/PAGE and Westernblot identified the HSP72 and 73 isoforms present in the tissue homogenates with low reactive intensity of the band corresponding to HSP73 in the after-lesion samples, without affecting significantly the HSP72 isoform. The analysis of TUNEL and PCNA double labelling showed decreasing of PCNA positive-uNK cells in the uterus after embryo-lesion and increasing of TUNEL positive nuclei. These results confirms the expression of HSP72 and HSP73 isoforms in the uNK cells through the gestation and to date, this is also the first report showing HSP70 in leukocytes, suggesting a cytoptotective function to this cell while working actively as important cells supporting the pregnancy. The decreasing of HSP72/73 positive uNK cells in the pregnant uterus triggered by embryo lesion consubstantiate the hypothesis of HSP72/73 working as cytoprotective chaperone in the uNK cells, and the HSP73 isoform in the mitochondria seems to be critical on down-regulation of apoptotic cell depth pathway / Mestrado / Histologia / Mestre em Biologia Celular e Estrutural

Understanding the cellular response thermal stress is important for improving thermoablative treatments of cancer. Cells generally respond to thermal stress by expressing heat shock proteins, or undergoing cell death by apoptosis or necrosis. Most of our detailed knowledge regarding these cellular phenomena has been gathered in vitro in two dimensional (2D) environments. Yet, little is known about how prostate cancer cells respond to thermal stress in a more physiologically relevant three dimensional (3D) environment. Several approaches were used to investigate this question, all of which focused on controlled heating of cells in both two dimensional (2D) and 3D culture. Tools and assays were developed to investigate cellular response to thermal stress in 2D and 3D environments. A computer-controlled heating apparatus was constructed to heat cell cultures to precise temperatures and durations. Three dimensional growth environments were produced using Matrigel, a commercially available extracellular matrix (ecm) mixture. Transcriptional expression of heat shock protein 70 (HSP70) was measured using a green fluorescent protein (GFP) reporter gene under the control of an HSP promoter. Apoptosis, necrosis and HSP70 transcription was measured using flow cytometry analysis. Quantitative polymerase chain reaction (qPCR) and microscopy revealed that transmembrane targets may be involved in the mechanism of the effect which 3D culture has on the cellular response to heat shock. The results herein demonstrate that the 3D growth environment, may be protective to the cell in that the percentage of cells that undergo apoptosis or necrosis when exposed to heat shock are reduced. Furthermore, HSP70 expression is enhanced in 3D culture at a specific thermal dose and integrins and heat shock proteins may be part of the mechanism by which the ecm exerts its protective effect against thermal stress. / text

No description available.