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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

The role of CD38 expression on NAD levels and cell physiology in a leukaemia model

Al-Abady, Zainab N. January 2014 (has links)
CD38 is a transmembrane glycoprotein with both ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase activities; it is also known as a cell surface receptor. CD38 utilizes NAD(P) as a substrate to produce the second messengers, Nicotinic acid adenine dinucleotide phosphate (NAADP) and Cyclic adenosine diphosphate ribose (cADPR). CD38 has been implicated in several diseases. For instance, in chronic lymphocytic leukemia (CLL), it is known as a poor prognostic marker and as a disease modifier. Also, abundant data are available on the receptor functions of CD38 in CLL. However, the aim of the work described in this thesis was to investigate the enzymatic functions of CD38 in leukemia. The work also addresses the question of why CD38+ subset leukemia patients are characterised by poor outcome. It has been postulated that CD38 is the major NADase in cells, and that knocking it down increases NAD levels significantly. Thus, it was hypothesized that NAD levels might be depleted and result in detrimental consequences on cell physiology when CD38 is significantly expressed. Also, it was suggested that a similar linkage might be also present in leukemia, contributing to poor outcome. To test this hypothesis, a human leukaemia cell line (HL60) was used as a convenient model that differentiates into CD38+ cells when stimulated using all-trans retinoic acid (ATRA). It is shown that CD38 is expressed extracellularly and intracellularly in the differentiated cells, as evaluated by qPCR, FACS, Western blotting and the NGD cyclization assay. However, one of the major consequences of the early expression of CD38 (at 3 h) was a substantial depletion of intracellular NAD+ levels that was apparent by 4 h after treatment with ATRA. These novel data suggest a major role for CD38 as a main regulator of NAD during the differentiation. The main role of CD38 in degradation of NAD was confirmed by using a CD38 inhibitor (kuromanin). Interestingly, the drop in NAD+ levels during the differentiation was reversed after treatment with kuromanin. Furthermore, the CD38 homologue, CD157, and other NAD-consuming enzymes (PARP and SIRT) were all investigated, and it was found that there are no substantial roles of all these enzymes on the NAD+ degradation during the differentiation. In contrast, qPCR results for NAD-biosynthesis enzymes during the differentiation process showed a significant rise in indolamine 2,3-dioxygenase (IDO) mRNA expression, with lesser increases in nicotinamide nucleotide adenyltransferase (NMNAT) and nicotinamide phosphoribosyl transferase (NAMPT) mRNA levels. The consequences of low NAD levels on cell metabolism were also assessed; the results show a reduction in lactate production and glutathione levels with an elevation of TBARS levels. However, the NAD+:NADH ratio remained relatively constant. Moreover, the effects of low NAD levels on DNA repair and cell death were also investigated in response to DNA damage caused by UVB. Preliminary findings show that, in CD38+ cells, there is a resistance to apoptotic cell death. Additionally, CD38 expression was also investigated in leukaemia cells, and was found to be regulated in response to hypoxic environment, or the change in NAD+ levels following FK866, kuromanin and NAD+ application. Altogether, these studies raise the possibility that the impact of CD38 enzymatic function on NAD levels and the negative consequences on NAD(P)-dependent processes might play an important role in the poor prognosis in CD38+ leukemia patients.
2

Perfil ClÃnico e Laboratorial dos Pacientes com Leucemia Linfoide CrÃnica Atendidos no ServiÃo de Hematologia e Hemoterapiado HUWC-HEMOCE / Clinical and Laboratorial Profile of Patients with Chronic Lymphocytic Leukemia admitted at the hematology and hemotherapy service of the University Hospital Walter CantÃdio (HUWC) and Hemotherapy and Hematology Center of Cearà (HEMOCE).

Richeyla Kelly de Assis CustÃdio 03 September 2009 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A leucemia linfocÃtica crÃnica (LLC) à a leucemia mais freqÃente nos paÃses ocidentais, ocorrendo em cerca de 30% de todas as leucemias do adulto, acometendo principalmente a populaÃÃo acima de 65 anos de idade. à caracterizada pela proliferaÃÃo clonal de linfÃcitos tipo B CD5 positivos. Do ponto de vista epidemiolÃgico, raramente à vista entre os orientais e a sua incidÃncia nÃo sofre influÃncia de agentes ambientais como substÃncias tÃxicas ou radiaÃÃes ionizantes. Os pacientes com LLC podem apresentar evoluÃÃo clÃnica variÃvel desde indolente a forma mais agressiva e rapidamente fatal. Na Ãltima dÃcada, houve um grande avanÃo no conhecimento da fisiopatologia desta doenÃa e fatores de prognÃstico de maior impacto foram estabelecidos e, do ponto de vista terapÃutico, novos medicamentos com maior eficÃcia surgiram. Desta forma à interessante conhecer a real situaÃÃo desta doenÃa com caracterÃsticas epidemiolÃgicas, clÃnicas e de prognÃstico muito peculiares. Nesse trabalho traÃamos o perfil (demogrÃfico, clÃnico e laboratorial) dos pacientes com LLC atendidos no serviÃo de Hematologia e Hemoterapia do Cearà (HEMOCE) do HUWC, correlacionando a expressÃo dos marcadores de prognÃstico (CD38 e ZAP-70) com algumas variÃveis e com o tratamento farmacolÃgico. Foram utilizadas amostras de sangue de 55 pacientes com LLC confirmados atravÃs de imunofenotipagem, em tratamento ou nÃo. Os marcadores CD38 e ZAP-70 foram analisados por citometria de fluxo e a dosagem de β2-microglobulina obtida atravÃs de mÃtodo imunoenzimÃtico (ELISA). Os dados obtidos foram analisados atravÃs de programa estatÃstico. Observamos um leve predomÃnio de pacientes do sexo masculino (1,4:1), 78% acima de 65 anos de idade e 60% eram procedentes da capital. Quanto ao estadiamento, 50,9% pacientes foram classificados como de baixo risco, segundo classificaÃÃo de Rai. Quanto a evoluÃÃo clÃnica, mais de 30% dos pacientes nÃo apresentavam sinais clÃnicos, nem no momento do diagnÃstico nem no final do estudo. Em relaÃÃo aos marcadores, 22,2% dos pacientes apresentavam expressÃo do ZAP-70 e 24,13% do CD38. NÃo houve diferenÃa estatÃsticamente significante entre os marcadores ZAP-70 e CD38 e as variÃveis hematolÃgicas (Hb, Ht e Plaquetas). Houve correlaÃÃo entre o estadiamento clÃnico de Rai e o tratamento farmacolÃgico e com os marcadores de prognÃstico (ZAP-70 e CD38). O perfil foi caracterizado por pacientes em estÃgios clÃnicos, segundo Rai, de baixo risco, com ausÃncia da expressÃo dos marcadores de prognÃstico (ZAP-70 e CD38) e com ausÃncia de tratamento especÃfico. / Chronic Lymphocytic Leukemia (CLL) is the most frequent leukemia on western countries, responding for 30% off all leukemia cases, reaching, specially, the under 65 years old population. It is characterized by accumulation of neoplasic mature B lymphocytes positives CD5. Concerning epidemiology, it is barely seen among eastern people, and its incidence is not influenced by environmental agents, such as toxic substances or ionizing radiation. CLL-B patients may present a variable clinical evolution, which goes from indolent to aggressive and rapidly fast cases. On last decade, there have been great advance on biology knowledge of this disease, and greater impact prognostic factors have been established. In relation to treatment, new medication, with better efficacy, appeared. Therefore, it is interesting to know the real situation of this disease, which has singular epidemiological, clinical and prognostic characteristics. In this work we trace the demographical, clinical and laboratorial profile of patients with CLL-B, at a state hemocenter (HEMOCE). We correlate prognostic markers expression (CD38 e ZAP-70) with some variable and with pharmacological treatment. We used 55 blood samples from patients CLL-B confirmed by their immunophenotypes; these patients may or may not be in treatment. CD38 and ZAP-70 were analyzed by flow cytometry and β2-microglobulin dosage, obtained through ELISA. Results were treated by statistic program. We see a discrete prevalence of male patients (1,4:1), 78% are under 65 years old and 60% live at CearÃâs capital. In relation to Rai staging system, 50,9% were classified as low risk patients. Concerning clinical evolution, more than 30% of the patients did not show clinical signs, neither at diagnose moment nor at the end of this study. In relation to the markers, 22,2% of the patients show ZAP-70 expression, and 24,13% show CD38 expression. There was no significant statistic difference between ZAP-70 and CD38 markers and hematological variable (Hb, Ht and platelets). There was correlation between Raiâs staging and pharmacological treatment and with prognostic markers. CONCLUSION: The profile was characterized by low risk patients, according Raiâs staging, it lacks prognostic markers expression and it also lacks specific treatment.
3

Verifiering Av Metod -För Dithiothreitolbehandling Av Testerytrocyter : För att möjliggöra antikroppsscreen vid BAS-test för daratumumab-behandlade patienter / Verifying the method of Dithiothreitol treatment of testerytrocytes : To enable antibody screening for daratumumab-treated patients

Karlsson, Linus January 2023 (has links)
Daratumumab är en antikropp som används vid behandling av multipelt myelom. Daratumumab är specifik för CD38, ytproteinet som uttrycks i stor mängd på myeloma plasmaceller. Vid antikroppsscreen orsakar daratumumab panreaktivitet då erytrocyter också uttrycker CD38. Dithiothreitol (DTT) behandling av testerytrocyter har visats kunna eliminera panreaktiviteten med daratumumab-antikropparna, detta genom att DTT klyver bort epitopet på CD38 som daratumumab reagerar mot utan att förstöra andra kliniskt relevanta antigen. På Södra Älvsborgs sjukhus skickas prover från daratumumab-behandlade patienter till Sahlgrenska sjukhuset för genotypning för att hitta kompatibelt blod. Förhoppningen är att den nya metoden ska möjliggöra antikroppsscreen på daratumumab-behandlade patienter vid Södra Älvsborgs sjukhus.Syftet med examensarbetet var att verifiera metoden för användning av DTT-behandlade testerytrocyter på plasma från daratumumab-behandlade patienter för att underlätta val av erytrocyter för blodtransfusion.Provmaterialet var venöst tagen patientplasma från 16 daratumumab-behandlade patienter testades mot 0,2 M DTT-behandlade- och obehandlade-testerytrocyter. DTT-behandlade testerytrocyter testades även mot kända antikroppar på plasmaprover från patienter som ej behandlats med daratumumab. Hållbarhetsstudie utfördes med behandlade BAS-testceller.Panreaktivitet sågs hos samtliga patientprover med obehandlade testerytrocyter. Vid test med DTT-behandlade testerytrocyter blev samtliga prover negativa. Behandlade testerytrocyter som testades mot kända antikroppar gav resultat som var oförändrat jämfört med originalscreen. Behandlade testceller var brukbara 25 dagar.DTT behandling av testerytrocyter är effektivt och billigt, resultatet var pålitligt då samtliga patientprover inte uppvisade panreaktivitet efter DTT-behandling av testerytrocyter. De DTT-behandlade erytrocyterna behöll kliniskt relevanta antigen efter behandling och var hållbara 25 dagar. Metoden anses som användbar för Södra Älvsborgs sjukhus. / Daratumumab is an antibody used for treatment of multiple myeloma. The antibody is specific for the surface protein CD38 which is being expressed in high quantity on myeloma plasma cells. Daratumumab is causing pan-reactivity during antibody screening due to regular erythrocytes also express CD38. Dithiothreitol (DTT) treatment of test erythrocytes has shown to eliminate the pan-reactivity caused by the daratumumab antibodies by cleaving the epitope on CD38 that daratumumab is specific to. Södra Älvsborgs hospital are currently sending patient samples from patients treated with daratumumab to Sahlgrenska hospital in Gothenburg for genotyping to find compatible blood.The purpose of the project was to verify the method for use of DTT-treated test erythrocytes on plasma from daratumumab treated patients to screen for antibodies and easier find compatible erythrocytes for blood transfusion at Södra Älvsborgs hospital.Plasma samples from 16 patients treated with daratumumab were tested with DTT-treated and untreated test erythrocytes. DTT-treated test erythrocytes were tested against samples with known antibodies from patients not treated with daratumumab. The cells durability was also tested.Pan-reactivity was shown with all daratumumab samples with non-treated test erythrocytes. Tests with DTT-treated test erythrocytes showed no pan-reactivity. Results from treated test erythrocytes tested against known antibodies were unchanged from original screening. The cells were durable for 25 days.DTT-treatment of test erythrocytes is effective and cheap, test results were reliable, all patient samples had their pan-reactivity eliminated. DTT-treated erythrocytes kept clinically significant antigens. The method is useful for clinical use at Södra Älvsborgs hospital.
4

The Role of SIRT1 in Preventing Mitochondrial Dysfunction with Obesity and Aging

Price, Nathan Loftus January 2012 (has links)
Mitochondrial function declines with aging and obesity, and has been implicated in the development of many age-related diseases. Caloric restriction (CR) prevents aging and has been shown to induce mitochondrial biogenesis and improve mitochondrial function. These effects may involve increased activity of the \(NAD^+\)-dependent deacetylase SIRT1. Indeed, overexpression of SIRT1 reproduces many of the health benefits of CR including induction of mitochondrial biogenesis by deacetylation and activation of the transcriptional co-activator \(PGC-1\alpha\). Because mitochondria regulate cellular functions important for aging, including, cellular energy production, ROS generation, and apoptosis, determining why mitochondrial function declines with age will improve our understanding of the underlying forces that drive organismal aging. Resveratrol and other SIRT1 activators induce mitochondrial biogenesis and protect against metabolic decline, but whether SIRT1 mediates these benefits is still a matter of debate. To circumvent the developmental defects of germ-line SIRT1 knockouts, we have developed the first inducible system that permits whole-body deletion of SIRT1 in adult mice. Obese mice treated with a moderate dose of resveratrol showed increased mitochondrial biogenesis and function, AMPK activation, and increased \(NAD^+\) levels in skeletal muscle, whereas SIRT1 knockouts displayed none of these benefits. Overexpression of SIRT1 in mice mimicked these effects, demonstrating that SIRT1 is sufficient and necessary for resveratrol to increase mitochondrial function in obese animals, and indicating a central role for SIRT1 in mediating the benefits of this molecule on muscle. Loss of SIRT1 or aging causes mitochondrial dysfunction and decreased expression of mitochondrial-encoded electron transport chain (ETC) components. This decrease in mitochondrial-encoded, but not nuclear-encoded ETC components in SIRT1 knockouts, which we have termed “genome asynchrony”, is independent of \(PGC-1\alpha\). Elevating \(NAD^+\) levels by treatment with the \(NAD^+\) precursor NMN prevented genome asynchrony and mitochondrial dysfunction in aged animals, similar to effects seen with CR. Together these data demonstrate that SIRT1 plays an essential role in preventing genome asynchrony, and that maintaining \(NAD^+\) levels and SIRT1 activity with age may prevent mitochondrial dysfunction. Since SIRT1 is required for NMN or resveratrol to improve mitochondrial function, compounds that activate SIRT1 or elevate \(NAD^+\) may help treat or prevent age-related diseases caused by mitochondrial dysfunction.
5

Differential effects of fingolimod on B-cell populations in multiple sclerosis / 多発性硬化症におけるB細胞亜群に対するフィンゴリモドの作用

Nakamura, Masakazu 25 November 2014 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12871号 / 論医博第2087号 / 新制||医||1006(附属図書館) / 31589 / 北海道大学大学院医学研究科臨床医学コース / (主査)教授 三森 経世, 教授 長澤 丘司, 教授 河野 憲二 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
6

Deficiency in Parkinson's Disease risk gene CD38 as it relates to glial function: dysregulation of astrocyte genes and bioenergetics as a result of CD38 deficiency

Hernandez, Raymundo Daniel 12 January 2024 (has links)
Parkinson's disease (PD) is the second most prevalent age-related neurodegenerative disease and currently affects over 8 million people worldwide. The primary features of PD include cognitive, behavioral, and motor function deficits induced primarily by the progressive loss of dopaminergic neurons within the substantia nigra of the basal ganglia (BG). Motor coordination becomes severely affected over the course of the disease, causing patients to experience tremors at rest, bradykinesia, and body rigidity. The availability of treatment options has increased the quality of life for patients experiencing the early stages of PD; however, there exists no cure and treatment options are limited for those experiencing severe, advanced disease symptoms. Genetic studies in PD patients have led to the identification of causative genes, but revealed that less than 20% of cases can be attributed to monogenic variations. Evidence strongly indicates that the majority of PD cases are idiopathic and likely driven due to gene by environmental interactions. Reflective of this idea, recent research efforts have turned to genome-wide association studies (GWAS) to provide indications of gene variations, that while not causative of PD, incur increased risk within patient populations. GWAS findings play a particularly crucial role in neurodegenerative interventions, as early identification of patient risk may allow for preventative therapeutics to delay disease onset or reduce symptom severity. Amongst the many gene variants identified as incurring increased PD risk, single-nucleotide polymorphisms (SNPs) in the loci for CD38 that cause reduced gene expression are consistently identified as increasing risk. The cluster of differentiation 38 (CD38) protein serves two major roles: one as a receptor for immunological response and a second as an ectoenzyme that modulates bioenergetic functions. The particular functions of CD38 are highly relevant to neurodegenerative contexts, as changes in central nervous system (CNS) inflammatory status and means of cellular energy production typically precede pathological indications. In the brain, CD38 expression is most enriched in astrocytes in BG regions, including substantia nigra, midbrain, and striatum. However, it is not known how CD38 deficiency may contribute to astrocytic dysfunction and neuropathological features of PD. This dissertation describes how CD38 influences astrocytic gene expression and cellular bioenergetics. Astrocyte RNA was sequenced from the BG of one-year old male Cd38+/+, Cd38+/-, and Cd38-/- mice by magnetic-activated cell sorting (MACS) to acquire astrocyte isolates. Numerous differentially expressed genes (DEGs) were identified in Cd38 Cd38+/- and Cd38-/- astrocytes that relate to regulation of cellular health, responses to stress, and bioenergetic functions. GO analysis further suggested mitochondrial dysfunction in both Cd38+/- and Cd38-/- astrocytes. In a subsequent set of experiments evaluating mitochondrial function by Seahorse XF96 platform, Cd38+/- and Cd38-/- astrocytes displayed altered bioenergetic function. The results herein demonstrate that astrocytic Cd38 expression regulates cellular function and implicates transcriptional changes associated with the hallmarks of neurodegeneration. These findings serve to provide future direction for studies evaluating the relationship between CD38 function and astrocytes as it relates to neurodegenerative PD risk. / Doctor of Philosophy / Parkinson's disease (PD) is the second most common age-related neurodegenerative disease and currently affects over 8 million people worldwide. The primary features of PD include cognitive, behavioral, and motor function deficits induced primarily by the progressive loss of specialized neurons within the substantia nigra of the basal ganglia (BG) brain region. Motor coordination becomes severely affected over the course of the disease, causing patients to experience body tremors, slowness, and rigidity. The availability of treatment options has increased the quality of life for patients experiencing the early stages of PD; however, there exists no cure and little treatment options for those experiencing severe, advanced disease symptoms. Genetic studies in PD patients have led to the identification of causative genes, but revealed that less than 20% of cases can be attributed to specific, individual variations. Evidence strongly indicates that the majority of PD cases are likely caused by small gene changes that interact with environmental factors. Recent research efforts have turned to genome-wide association studies (GWAS) to identify these small changes, that while not causative of PD, may increase risk within patient populations. GWAS findings play a particularly crucial role in treating neurodegenerative diseases, as early identification of patient risk may allow for preventative therapeutics to slow disease onset or reduce symptom severity. Amongst the many small gene changes identified as increasing PD risk, changes in the gene CD38 that cause reduced gene expression are consistently identified as increasing risk. The cluster of differentiation 38 (CD38) protein serves two major roles: one as a receptor for immune responses and a second as an enzyme that impacts how cells produce energy. The functions of CD38 are highly relevant to neurodegenerative contexts, as changes in central nervous system (CNS) inflammatory status and means of cellular energy production typically precede disease pathology. In the brain, CD38 expression is most enriched in astrocytes, specialized brain cells that supports neurons, in regions affected by PD. However, it is not known how CD38 deficiency may contribute to astrocytic dysfunction and neuropathological features of PD. This dissertation describes how CD38 influences astrocytic gene expression and cellular bioenergetics. Astrocyte RNA was sequenced from the BG of one-year old male Cd38+/+, Cd38+/- (50% CD38 loss), and Cd38-/- (100% CD38 loss) mice by magnetic-activated cell sorting (MACS) to acquire astrocytes. Numerous changes in gene expression were identified in Cd38 Cd38+/- and Cd38-/- astrocytes that relate to regulation of cellular health, responses to stress, and energy functions. Further analysis looking at functions, suggested mitochondrial abnormalities in both Cd38+/- and Cd38-/- astrocytes. In a subsequent set of experiments evaluating mitochondrial function by Seahorse XF96 platform, Cd38+/- and Cd38-/- astrocytes displayed altered energetic function. The results herein demonstrate that astrocytic Cd38 expression regulates cellular function and implicates transcriptional changes associated with the hallmarks of neurodegeneration. These findings serve to provide future direction for studies evaluating the relationship between CD38 function and astrocytes as it relates to neurodegenerative PD risk.
7

Ditiotreitol-behandling av erytrocyter vid förenlighetsprövning av blod till patienter med Darzalex medicinering / Dithiothretiol treatment of erythrocytes in compatibility testing of blood to patients with Darzalex medication

Ghilai, Merry January 2021 (has links)
Introduktion: Daratumumab är en monoklonal antikropp som används för att behandla patienter med multipelt myelom (MM), en typ av blodcancer som har sitt ursprung i B-lymfocyter. Daratumumab binder till CD38 som normalt uttrycks på erytrocyternas yta och ger upphov till panreaktivitet vid förenlighetsprövning, som kan maskera kliniskt signifikanta antikroppar. Ditiotreitol (DTT), ett reducerande lösningsmedel, denaturerar den extracellulära domänen av CD38 och därmed hämmar inbindning av daratumumab. DTT-behandling av testerytrocyter vid förenlighetsprövning möjliggör detektion av kliniskt relevanta alloantikroppar.  Syfte: Att verifiera en metod för DTT-behandling av erytrocyter vid förenlighetsprövning, för att detektera alloantikroppar av klinisk relevans och lättare få fram blod till patienter som medicineras med Darzalex.  Metod & materiel: I studien ingick två plasmaprover från patienter med daratumumab behandling. Testerytrocyterna behandlades med olika DTT mängd (80, 160 och 320 L). DTT-behandlade samt obehandlade testerytrocyter testades mot plasmaproverna, negativ kontroll (anti-K) och positiv kontroll (anti-C) vid olika dagar från tillredningsdatum.  Resultat: Daratumumab interferens mot obehandlade testerytrocyter observerades. Reaktionen för samtliga DTT-behandlade testceller vid varje analystillfälle blev negativt, oavsett DTT mängd. Resultaten för den negativa kontrollen visade att det slog positivt vid DTT mängden 80 samt 160 µL och negativ vid 320 µL. Alla reaktioner för den positiva kontrollen var 4+ vid samtliga DTT mängder oavsett analysdag.  Slutsats:  DTT-behandling av erytrocyter inaktiverar CD38 som motverkar panreaktivitet vid serologiska analyser, för att upptäcka eventuella kliniskt signifikanta antikroppar hos patienter som behandlas med daratumumab. Den optimala DTT mängden är 320 µL/1 ml 1% testerytrocyt med upp till 15 dagars hållbarhet vid kylförvaring. / Introduction: Daratumumab is a monoclonal antibody used to treat patients with multiple myeloma (MM), a type of blood cancer that originates in B lymphocytes. Daratumumab binds to CD38, which is expressed on the surface of erythrocytes. This leads to panagglutination in compatibility testing and can mask clinically significant antibodies. Dithiothreitol (DTT), a reductant, denatures the extracellular domain of CD38, thereby inhibiting daratumumab from binding. DTT treatment of RBC-reagents enables the detection of clinically relevant alloantibodies. Purpose: To verify a method for DTT treatment of erythrocytes in compatibility testing, in order to detect alloantibodies of clinical relevance and to ensure that transfusion recipient with Darzalex medication receive compatible blood transfusion. Method: Two plasma samples from daratumumab treated patients were included. RBC-regents were treated with different amounts of DTT (80, 160 and 320 μL). DTT-treated and untreated RBC-reagents were tested against plasma samples, negative control (anti-K) and positive control (anti-C) on different days.  Results: Daratumumab interference with untreated RBC-reagents were observed.  DTT treated RBC-reagents however, showed negative reaction regardless of the amount of DTT used. Results for the negative control showed positive reaction with 80 and 160 µL DTT and negative at 320 µL. Reactions for the positive control were all 4+ no matter the amount of DTT and day it was analyzed.   Conclusion: DTT treatment of erythrocytes inactivates CD38, which prevents panagglutination, to detect any clinically significant antibodies in patients with daratumumab treatment. The optimal DTT amount is 320 µL / 1 ml 1% RBC-reagents and a shelf life of up to 15 days when stored cold.
8

Caracterização fenotípica e funcional de linfócitos TCD8+ circulantes na síndrome de Sézary / Phenotypic and functional characterization of circulating CD8+ T lymphocytes in Sezary syndrome

Torrealba, Marina Passos 16 September 2016 (has links)
INTRODUÇÃO: A Síndrome de Sézary (SS) é um linfoma cutâneo de células T (LCCT), caracterizado por eritrodermia, linfadenopatia generalizada e presença de células tumorais na pele, linfonodos e sangue periférico. Os linfócitos TCD8+ têm papel fundamental na resposta imune antitumoral, entretanto, há escassos estudos evidenciando seu perfil fenotípico e funcional. Considerando que a resposta imunológica do paciente com SS está suprimida, estratégias para potencializar a imunidade inata e adaptativa com agonistas de receptores Toll-like (TLRs) têm sido exploradas. OBJETIVO: Caracterizar o perfil de marcadores de ativação/inibição das células TCD8+, seus estágios de diferenciação, capacidade de resposta a IL-7/IL-15 e ao agonista de TLR7/TLR8 de pacientes com SS. METODOLOGIA: Foram selecionados 15 pacientes com SS (7 homens e 8 mulheres) com 48-85 anos do Ambulatório de Linfomas Cutâneos, do HC-FMUSP, e um grupo de controle com 24 indivíduos sadios. A análise de marcadores de ativação/inibição e diferenciação celular em células TCD4/TCD8+ do sangue periférico foi realizada por citometria de fluxo. A expressão de marcadores extracelulares e citocinas intracelulares em células mononucleadas do sangue periférico (CMN) após estimulação com o agonista de TLR7/TLR8 foi analisada por citometria de fluxo. Além disto, o efeito de IL-7 e IL-5 em células T foi avaliado pela fosforilação de STAT5, na capacidade de proliferação mitogênica e expressão de BCL-2 em CMNs, como também pelos níveis séricos de IL-7 por citometria de fluxo. RESULTADOS: Os pacientes com SS mostram perfil fenotípico de ativação crônica nos linfócitos TCD8+ periféricos, decorrente do elevadopercentual de células TCD8+ CD38+, redução percentual de TCD8+ CD127+ (IL-7R) e da população naive. Além disso, ocorreu aumento de expressão de PD-1 na população naive de células TCD8+. O marcador de ativação, CD26, até então apenas relacionado com linfócitos TCD4, foi detectado em reduzida percentagem de linfócitos TCD8. A resposta para IL-7/IL-15 parece estar funcionalmente presente tanto nos linfócitos TCD4 quanto nos linfócitos TCD8. Contudo, foi encontrado um perfil diferenciado e heterogêneo de fosforilação de STAT5 assim como de expressão de BCL-2 nos linfócitos TCD8+ de pacientes com SS. O nível sérico de IL-7 reduzido dos pacientes com SS foi inversamente correlacionado com o número absoluto de linfócitos TCD4+. CONCLUSÃO: Os linfócitos TCD8+ dos pacientes com SS encontram-se reduzidos em números absolutos, e possuem um perfil alterado de diferenciação celular e expressão de marcadores extracelulares. A redução percentual da população de TCD8+ naive associada com a presença de moléculas de ativação crônica mostra um perfil de imunosenescência. As células TCD8+ exibem baixa capacidade de resposta aos ligantes de TLR intracelulares, provavelmente devido ao perfil de ativação crônica. Além disso, há resposta parcial dos linfócitos TCD8+ às citocinas ligantes do receptor yc. Nossos resultados evidenciam alterações em linfócitos TCD8+ que debilitam a resposta imune antitumoral e que pode contribuir com a patogênese da síndrome de Sézary / INTRODUCTION: Sézary syndrome (SS) is a cutaneous T cell lymphoma (CTCL), characterized by erythroderma, generalized lymphadenopathy and the presence of tumor cells in the skin, lymph nodes and peripheral blood. The TCD8+ lymphocytes play a key role in anti-tumor immune response, whereas, there are few studies showing its phenotypic and functional profile in SS. Considering that the immune response of SS patient is suppressed, strategies to enhancing the innate and adaptive immunity by Toll-like receptors (TLRs) agonists have been explored. OBJECTIVE: To characterize the profile of activation/inhibition markers of CD8+ T cells, their stages of differentiation, ability of response to IL-7/IL-15 and TLR7/TLR8 agonist of patients with SS. METHODOLOGY: Fifteen SS patients were enrolled (7 men and 8 woman) with 48-85 years from the Clinic of Cutaneous Lymphomas, HC-FMUSP, and a control group of 24 healthy individuals. Analysis of activation/inhibition markers and cellular differentiation in CD4/CD8 T cells from peripheral blood were assessed by flow cytometry. The expression of extracellular markers and intracellular cytokines in mononuclear cells in the peripheral blood (CMN) were evaluated by flow cytometry. Moreover, the effect of IL-7 and IL-15 stimulation in T cells was assessed by the STAT5 phosphorylation, proliferative mitogenic capacity, BCL-2 expression in CMNs as well as serum IL-7 levels by flow cytometry. RESULTS: Patients with SS show a phenotypic CD8 T peripheral lymphocytes profile of chronic activation, due to the high percentage of CD8+CD38+ T cells, reduced percentage of CD8+CD127+ (IL-7R) and naïve population. Furthermore, it was observed an increased PD-1 expression in the naïve CD8+ T cells. The activation marker CD26, previously only associated with CD4 T lymphocyte, was detected at decreased percentage in CD8 T lymphocytes. The TLR7/TLR8 agonist did not affect the IFN-? and TNF secretion of CD8 T lymphocytes of SS patients, in contrast to the control group. The response to IL-7/IL-15 appears to be functional in both CD4 and CD8 T lymphocytes. However, it was founded a differentiated and heterogeneous profile of STAT5 phosphorylation and Bcl-2 expression in the CD8 T lymphocytes in SS patients. The reduced IL-7 serum of patients with SS was inversely correlated with the absolute number of CD4 T lymphocytes. CONCLUSION: CD8 T lymphocytes of patients with SS are reduced in absolute numbers, and show an altered cellular differentiation profile and extracellular markers expression. The reduced percentage of CD8 naïve population associated with chronic activation of molecules reveals an immunosenescence profile. The CD8 T cells exhibit low ability to ligands of intracellular TLR receptors, probably due to chronic activation profile. In addition, there are partial response of CD8 T lymphocytes to the cytokine receptor ?c. Our results show disturbance in CD8 T lymphocytes that may impair the anti-tumor response contributing to the pathogenesis of Sézary syndrome
9

Caracterização fenotípica e funcional de linfócitos TCD8+ circulantes na síndrome de Sézary / Phenotypic and functional characterization of circulating CD8+ T lymphocytes in Sezary syndrome

Marina Passos Torrealba 16 September 2016 (has links)
INTRODUÇÃO: A Síndrome de Sézary (SS) é um linfoma cutâneo de células T (LCCT), caracterizado por eritrodermia, linfadenopatia generalizada e presença de células tumorais na pele, linfonodos e sangue periférico. Os linfócitos TCD8+ têm papel fundamental na resposta imune antitumoral, entretanto, há escassos estudos evidenciando seu perfil fenotípico e funcional. Considerando que a resposta imunológica do paciente com SS está suprimida, estratégias para potencializar a imunidade inata e adaptativa com agonistas de receptores Toll-like (TLRs) têm sido exploradas. OBJETIVO: Caracterizar o perfil de marcadores de ativação/inibição das células TCD8+, seus estágios de diferenciação, capacidade de resposta a IL-7/IL-15 e ao agonista de TLR7/TLR8 de pacientes com SS. METODOLOGIA: Foram selecionados 15 pacientes com SS (7 homens e 8 mulheres) com 48-85 anos do Ambulatório de Linfomas Cutâneos, do HC-FMUSP, e um grupo de controle com 24 indivíduos sadios. A análise de marcadores de ativação/inibição e diferenciação celular em células TCD4/TCD8+ do sangue periférico foi realizada por citometria de fluxo. A expressão de marcadores extracelulares e citocinas intracelulares em células mononucleadas do sangue periférico (CMN) após estimulação com o agonista de TLR7/TLR8 foi analisada por citometria de fluxo. Além disto, o efeito de IL-7 e IL-5 em células T foi avaliado pela fosforilação de STAT5, na capacidade de proliferação mitogênica e expressão de BCL-2 em CMNs, como também pelos níveis séricos de IL-7 por citometria de fluxo. RESULTADOS: Os pacientes com SS mostram perfil fenotípico de ativação crônica nos linfócitos TCD8+ periféricos, decorrente do elevadopercentual de células TCD8+ CD38+, redução percentual de TCD8+ CD127+ (IL-7R) e da população naive. Além disso, ocorreu aumento de expressão de PD-1 na população naive de células TCD8+. O marcador de ativação, CD26, até então apenas relacionado com linfócitos TCD4, foi detectado em reduzida percentagem de linfócitos TCD8. A resposta para IL-7/IL-15 parece estar funcionalmente presente tanto nos linfócitos TCD4 quanto nos linfócitos TCD8. Contudo, foi encontrado um perfil diferenciado e heterogêneo de fosforilação de STAT5 assim como de expressão de BCL-2 nos linfócitos TCD8+ de pacientes com SS. O nível sérico de IL-7 reduzido dos pacientes com SS foi inversamente correlacionado com o número absoluto de linfócitos TCD4+. CONCLUSÃO: Os linfócitos TCD8+ dos pacientes com SS encontram-se reduzidos em números absolutos, e possuem um perfil alterado de diferenciação celular e expressão de marcadores extracelulares. A redução percentual da população de TCD8+ naive associada com a presença de moléculas de ativação crônica mostra um perfil de imunosenescência. As células TCD8+ exibem baixa capacidade de resposta aos ligantes de TLR intracelulares, provavelmente devido ao perfil de ativação crônica. Além disso, há resposta parcial dos linfócitos TCD8+ às citocinas ligantes do receptor yc. Nossos resultados evidenciam alterações em linfócitos TCD8+ que debilitam a resposta imune antitumoral e que pode contribuir com a patogênese da síndrome de Sézary / INTRODUCTION: Sézary syndrome (SS) is a cutaneous T cell lymphoma (CTCL), characterized by erythroderma, generalized lymphadenopathy and the presence of tumor cells in the skin, lymph nodes and peripheral blood. The TCD8+ lymphocytes play a key role in anti-tumor immune response, whereas, there are few studies showing its phenotypic and functional profile in SS. Considering that the immune response of SS patient is suppressed, strategies to enhancing the innate and adaptive immunity by Toll-like receptors (TLRs) agonists have been explored. OBJECTIVE: To characterize the profile of activation/inhibition markers of CD8+ T cells, their stages of differentiation, ability of response to IL-7/IL-15 and TLR7/TLR8 agonist of patients with SS. METHODOLOGY: Fifteen SS patients were enrolled (7 men and 8 woman) with 48-85 years from the Clinic of Cutaneous Lymphomas, HC-FMUSP, and a control group of 24 healthy individuals. Analysis of activation/inhibition markers and cellular differentiation in CD4/CD8 T cells from peripheral blood were assessed by flow cytometry. The expression of extracellular markers and intracellular cytokines in mononuclear cells in the peripheral blood (CMN) were evaluated by flow cytometry. Moreover, the effect of IL-7 and IL-15 stimulation in T cells was assessed by the STAT5 phosphorylation, proliferative mitogenic capacity, BCL-2 expression in CMNs as well as serum IL-7 levels by flow cytometry. RESULTS: Patients with SS show a phenotypic CD8 T peripheral lymphocytes profile of chronic activation, due to the high percentage of CD8+CD38+ T cells, reduced percentage of CD8+CD127+ (IL-7R) and naïve population. Furthermore, it was observed an increased PD-1 expression in the naïve CD8+ T cells. The activation marker CD26, previously only associated with CD4 T lymphocyte, was detected at decreased percentage in CD8 T lymphocytes. The TLR7/TLR8 agonist did not affect the IFN-? and TNF secretion of CD8 T lymphocytes of SS patients, in contrast to the control group. The response to IL-7/IL-15 appears to be functional in both CD4 and CD8 T lymphocytes. However, it was founded a differentiated and heterogeneous profile of STAT5 phosphorylation and Bcl-2 expression in the CD8 T lymphocytes in SS patients. The reduced IL-7 serum of patients with SS was inversely correlated with the absolute number of CD4 T lymphocytes. CONCLUSION: CD8 T lymphocytes of patients with SS are reduced in absolute numbers, and show an altered cellular differentiation profile and extracellular markers expression. The reduced percentage of CD8 naïve population associated with chronic activation of molecules reveals an immunosenescence profile. The CD8 T cells exhibit low ability to ligands of intracellular TLR receptors, probably due to chronic activation profile. In addition, there are partial response of CD8 T lymphocytes to the cytokine receptor ?c. Our results show disturbance in CD8 T lymphocytes that may impair the anti-tumor response contributing to the pathogenesis of Sézary syndrome
10

Enzymatic Regulation of Opioid Antinociception and Tolerance

Hull, Lynn 12 July 2009 (has links)
ENZYMATIC REGULATION OF OPIOID ANTINOCICEPTION AND TOLERANCE By Lynn C. Hull, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2009 Director: William L. Dewey, Ph.D. Department of Pharmacology and Toxicology The involvement of kinases in opioid actions has long been established. The acute actions of opioids, through the Gi/Go G-proteins, cause the inhibition of adenylyl cyclase and therefore a decrease in protein kinase A (PKA) activation. Additionally, acute opioid administration may cause the G-protein to activate the phospholipase C (PLC)-mediated cascade leading to the activation of protein kinase C (PKC). The phosphorylation of the MOR which can lead to both desensitization by uncoupling of the G-protein coupled receptors (GPCRs) from the G-proteins and to internalization by recruitment of β-arrestins has long been identified as a key process in tolerance. Phosphorylation by PKA and PKC leads primarily to uncoupling of the receptor from the G-proteins. Phosphorylation of the receptor by G-protein coupled receptor kinase (GRK) leads to the recruitment of β-arrestins and internalization of the receptor. Many in vitro studies have come to the conclusion that GRK induced internalization plays a more central role in the tolerance to high efficacy opioids and a lesser role in low- and moderate-efficacy opioid tolerance. In fact it has been hypothesized that morphine, a moderate-efficacy opioid, causes no internalization at all, while the desensitization of the receptor via phosphorylation by PKA and PKC plays a more central role in low- and moderate-efficacy opioid tolerance. We sought to test these in vitro findings in an in vivo model of opioid tolerance. Animals were made tolerant to one of a number of opioids of varying efficacy (low-efficacy meperidine, moderate-efficacy morphine and fentanyl, and high-efficacy [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO)) over an 8 hour period and then were administered one of the kinases’ inhibitors. Tolerance reversal was determined by challenging these mice with the same opioids to which they were tolerant. Calcium is known to play an important role in the acute antinociceptive actions of opioids as well as in opioid tolerance. Therefore it is important to determine how opioids are affecting the regulation of intracellular calcium. Our laboratory has previously shown that Calcium Induced Calcium Release (CICR), the ryanodine receptor and intracellular microsomal Ca2+ pools all play a role in opioids’ actions. It is also well known that mammalian ADP-ribosyl cyclase, CD38’s, product cADPR acts on the ryanodine receptor to cause Ca2+ release into the intracellular space. We chemically and genetically altered CD38 and then tested the acute effect of morphine as well as what effect these treatments had on morphine tolerance to determine what role if any, that CD38 may play in the acute actions of morphine antinociception as well as in morphine tolerance. Together, studies focusing on the role of an ADP-ribosyl cyclase, CD38, and 3 separate kinases, PKA, PKC and GRK, in opioids’ actions were performed in order to better understand the roles of these enzymes’ pathways in the actions of opioid-induced antinociception and subsequent development of tolerance. It is hoped that the results herein add useful knowledge to the general understanding of this drug class, and will one day be of use in the development of future analgesics and in the clinical treatment of pain and reduction in tolerance.

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