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Marcadores de ativaÃÃo de linfÃcitos T e de suas citocinas como ferramentas diagnÃsticas na hipersensibilidade alÃrgica a fÃrmacos / Markers of T lymphocyte activation and its cytokines as diagnostic tools in drug allergyFabricia Martins Teixeira 29 February 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / As reaÃÃes alÃrgicas a fÃrmacos representam um terÃo das reaÃÃes adversas a medicamentos, e embora sejam pouco freqÃentes, apresentam altas taxas de morbidade e mortalidade, revelando um importante problema de saÃde pÃblica. Os principais desafios relacionados com a hipersensibilidade a fÃrmacos decorrem do fato de sua imprevisibilidade, de que nÃo existe um modelo animal para pesquisa e devido à variabilidade individual no que diz respeito ao metabolismo do fÃrmaco. As reaÃÃes alÃrgicas a medicamentos sÃo difÃceis de serem diagnosticadas, uma vez que hà carÃncia de mÃtodos laboratoriais para sua investigaÃÃo. O presente estudo teve como objetivo estabelecer alguns mÃtodos imunolÃgicos in vitro para o diagnÃstico de alergia a medicamentos. Vinte pacientes atendidos no AmbulatÃrio de Dermatologia do Hospital UniversitÃrio Walter CantÃdio, Universidade Federal do CearÃ, com manifestaÃÃes muco-cutÃneas e sistÃmicas decorrentes de hipersensibilidade a fÃrmacos foram investigados atravÃs de histÃria clÃnica, exames laboratoriais in vivo e in vitro. Foram avaliados os marcadores de ativaÃÃo de linfÃcitos CD25 e CD69 atravÃs de citometria de fluxo, em cÃlulas mononucleares do sangue perifÃrico previamente incubadas com diferentes concentraÃÃes do fÃrmaco suspeito, e anÃlise das citocinas interferon γ e interleucina 5 no sobrenadante da cultura atravÃs de teste imunoenzimÃtico. Dezoito pacientes foram submetidos aos testes cutÃneos, sendo que nove mostraram resultados positivos a um ou mais fÃrmacos. Quinze pacientes apresentaram positividade para pelo menos um dos marcadores de ativaÃÃo em resposta ao fÃrmaco suspeito. Os marcadores CD69 e/ou CD25 foram expressos pelas cÃlulas T CD4+ e CD8+, tanto em reaÃÃes imediatas como nas nÃo imediatas. A comparaÃÃo dos Ãndices de estimulaÃÃo desses marcadores entre pacientes e indivÃduos saudÃveis nÃo alÃrgicos, resultou em diferenÃa significativa para CD4+CD69+ nas trÃs concentraÃÃes do fÃrmaco suspeito e para CD4+CD25+ apenas na menor concentraÃÃo do fÃrmaco suspeito. Nenhuma diferenÃa significativa para as citocinas IFN-γ e IL-5 foi observada entre os pacientes e os indivÃduos controles. A detecÃÃo de ambos os marcadores de ativaÃÃo CD69 e CD25 aumentou a sensibilidade diagnÃstica do teste. O uso combinado dos marcadores representa uma ferramenta promissora no diagnÃstico laboratorial das reaÃÃes alÃrgicas a medicamentos. NÃo obstante, essa hipÃtese deve ser confirmada com um nÃmero maior de pacientes e controles. / Drug allergy reactions represent one third of adverse drug reactions, and although they are infrequent, they present high rates of morbidity and mortality, revealing a major public health problem. The main challenges related to drug hypersensitivity result from its unpredictability, no animal model for research and individual variability with regard to drug metabolism. Drug allergy reactions are difficult to be diagnosed once there is a lack of laboratorial tests for their investigation. The present study aimed to establish some immunological in vitro methods for diagnosing drug allergy. Patients (n=20) attending a dermatology outpatient clinic, Hospital Universitario Walter CantÃdio, Universidade Federal Ceara, with mucocutaneous and systemic manifestations due to drug hypersensitivity were investigated by clinical history, laboratory findings, and in vivo and in vitro tests. The lymphocyte activation markers, CD25 and CD69, were evaluated by flow cytometry on the peripheral blood mononuclear cells previously incubated with different concentrations of the suspected drug, and analysis of interferon γ and interleukin 5 was done in the culture supernatant by enzyme immunoassay. Eighteen patients were tested by skin tests; nine patients showed positive results to one or more drugs. Fifteen patients showed positivity for at least one of activation markers in response to the suspected drug. The markers CD69 and/or CD25 were expressed by T cells CD4+ and CD8+, both in immediate and delayed reactions. Comparing stimulation index of the markers between patients and healthy no allergic individuals, it was observed a significant difference for CD4+CD69+ in the three suspected drug concentrations and CD4+CD25+ only in the lower drug concentration. No significant differences were found for the cytokines IFN-γ and IL-5 between patients and healthy individuals. The detection of both activation markers CD69 and CD25 increased the diagnostic sensitivity of the test. The use of both markers represents a promising tool in drug allergy diagnosis. Nonetheless, this hypothesis needs to be confirmed with a greater number of patients and controls.
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Development and validation of stabilized whole blood samples expressing T-cell activation markers as quality control reference materialLouw, Anne-Rika 03 1900 (has links)
Thesis (MScMed)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Introduction: Flow cytometry has progressively replaced many traditional laboratory
tests due to its greater accuracy, sensitivity and rapidity in the routine clinical settings
especially clinical trails. It is a powerful tool for the measuring of chemical (the
fluorochrome we add) and physical (size and complexity) characteristics of individual
cells. As these instruments became major diagnostic and prognostic tools, the need for
more advanced quality control, standardized procedures and proficiency testing
programs increased as these instrumentations and their methodology evolve. Minor
instrument settings can affect the reliability, reproducibility and sensitivity of the
cytometer and should be monitored and documented in order to ensure identical
conditions of measurement on a daily basis. This can be accomplished by following an
Internal Quality Assurance (IQA) and/ or External Quality Assurance (EQA) program.
Currently there are no such programs available in South Africa and poorer Africa
countries. HIV is a global concern and the laboratories and clinics in these places are in
need of such IQA programs to ensure quality of their instrumentation and accurate
patient results. Quality assurance programs such as CD Chex® and UK Nequas are
available but due to bad sample transport, leave the receiving laboratories with
nightmares. It would be best if there was a laboratory in South Africa that could
provide the surrounding laboratories with stabilized whole blood samples that can be
utilized as IQA. The transport of these samples can be more efficient due to shorter
distance and thus the temperature variations limited. Aims and Objectives: The aim of Chapter one is to familiarize the reader with general
terminology and concepts of immunology. Chapter two describes in detail the impact
stabilized whole blood had on clinical immunology concerning Quality Control and
Quality Assurance. The objective of this study is to stabilize whole blood with a shelf
life of greater than 30 days to serve as reference control material for South African
Immunophenotyping. It is further an objective to use these in-house stabilized control
samples for poorer African countries as Internal Quality Assurance reference material.
It is a still further objective to stimulate various lymphocyte subsets to express
activation antigens and then stabilize these cells for more specialized immunological
test and can serve as a QC for those required samples.
Study design: In Chapter three, the method currently used to stabilize whole blood was
modified. The stability of different concentrations of a first stabilizing agent
(Chromium Chloride hexahydrate) was investigated. Incubation periods and
concentrations of paraformaldehyde as second stabilizing agent were investigated.
Blood samples from healthy individuals (n=10) were stabilized and monitored for the
routine HIV phenotypic surface antigens over a period of 40 days. These samples
(n=10) were compared on the Becton Dickinson Biosciences (BD) FACSCalibur™
versus BD FACSCount™ instrumentation. Blood samples (n=3) were stabilized and
monitored to identify phenotypic cell surface molecules for as long as possible. They
were quantified on both flow cytrometric instruments. In addition, these stabilized
samples (n=3) were investigated as control blood for calibration purposes on the BD
FACSCount™ instrument. In Chapter four, lymphocytes were isolated and activated with various stimuli to
express sufficient activation antigens such as CD25, CD69, HLA-DR and CD40
Ligand on the T helper cell surfaces. These activated antigens were analyzed on the
BD FACSCalibur™ and further stabilized to serve as possible IQA samples in future.
Results: In Chapter three, the ten individual stabilized samples had non-significant P
values (P > 0.05) for CD3, CD4 and CD8 percentages and absolute values comparing
day 3 until day 40. Comparing the BD FACSCalibur™ versus BD FACSCount™,
resulted in a R2 = 0.9848 for CD4 absolute values and a R2 = 0.9636 for CD8 absolute
values. Stabilized blood samples (n=3) were monitored for routine HIV phenotypic
markers until day 84. The cells populations were easily identifiable and could be
quantified on both BD FACSCalibur™ and BD FACSCount™ instruments.
In Chapter four; for the activation study purposes, activated T helper lymphocytes
expressed approximately 25 to 35% CD40 Ligand cell surface molecules. The
stimulant of choice was Ionomycin at a 4μM concentration. Cells were incubated for
four hours at 37 degree Celsius in a 5% CO2 environment. For CD69 surface
expression, 6 hour incubation was optimum. The stimulus of choice in this case was
4μM Ionomycin which induced 84.21% CD69 expression in the test samples. For
CD25 expression; 6 hour incubation with PHA resulted in approximately 43% of CD25
expression. For HLA-DR surface expression; 6 hour incubation with PHA resulted in
approximately 43.32% of HLA-DR expression. Activated lymphocytes expressing
CD40 Ligand showed stability until day 23. Activated Lymphocytes expressing CD69,
CD25 and HLA-DR were stabilized in the same manner and stability could be
achieved until day 16. Conclusion: This thesis was related to the preparation of control samples (IQA)
designed to simulate whole blood having defined properties in clinical laboratory
situations. In future kits can be developed with a low, medium and high control sample
for the various immunological phenotypic determinants. Another kit can be compiled
where various activation markers can be identified, quantified with a “zero”, low and
high control. These whole blood IQA kits and “activation IQA kits” can be
implemented for training of newly qualified staff, competency testing of staff, method
development, software testing, panel settings and instrument setting testing. Control
samples ideally must have a number of properties in order to be effective. For instance
stability during storage times, preferably lasting more than a few weeks,
reproducibility and ease of handling. These will provide the information on day-to-day
variation of the technique or equipment which will enhance accuracy and improve
patient care. / AFRIKAANSE OPSOMMING: Inleiding: Vloeisitometrie tegnologie het verskeie tradisionele laboratorium toetse
vervang as gevolg van beter akuraadheid, sensitiwiteit en vinniger beskikbaarheid van
resultate in ‘n kliniese omgewing, veral kliniese proewe. Vloeisitometrie is ‘n kragtige
tegniek om chemiese (fluorokroom byvoeging) en fisiese (sel grote en kompleksiteit)
karakter eienskappe van individuele selle te meet. Met die toename in gebruik en
gewildheid van hiedie instrumente, neem die behoefde toe vir gevorderde kwaliteit
kontroles, gestandardiseerde prosedures, met profesionele toets programme tesame met
metode ontwikkeling.
Klein verstellings aan instrument parameters beinvloed die betroubaarheid,
herhaalbaarheid en sensitiwiteit van ‘n sitometer en moet gemonitor (en dokumenteer)
word om identiese kondisies van leesings op ‘n daaglikse basis te verseker. Dit kan
bereik word deur in te skakel met ‘n interne kwaliteits versekerings program [IQA:
“Internal Quality Control”] en/of ‘n eksterne kwaliteits versekerings program [EQA:
“External Quality Control”] te volg. Op die oomblik is daar geen sulke kwaliteits
versekerings programme in Suid Afrika en/of in die verarmende Afrika lande
beskikbaar nie. MIV is ‘n wêreldwye bekommernis en laboratoriums en klinieke in
hierdie gedeeltes van die land verlang ‘n dringende behoefdte vir sulke “IQA”
programme om kwaliteit van instrumentasie en akkurate pasiënt resultate te verseker
wat tot beter behandeling van pasiënte lei. Kwaliteit versekerings programme soos
“CD Chex®” en “UK Nequas” is beskikbaar, maar baie probleme met verwysing na
monster integriteit as gevolg van tydsame vervoer en aflewering kondisies word
hiermee geassosieër. Die behoefte het ontstaan vir ‘n laboratorium in Suid Afrika wat direk die omliggende
laboratoriums, hospitale en klinieke kan voorsien met gestabiliseerde blood monsters
wat gebruik kan word as “IQA”. Die vervoer en aflewerings kondisies van hierdie
monsters sal aansienlik verbeter as gevolg van die korter aflewerings afstand wat direk
die beperkte temperatuur wisseling beinvloed.
Doel van studie: Die doelwit van hoofstuk een is om vir die leser ‘n inleiding te gee
tot terminologie en konsepte van immunologie en die immune sisteem. Hoofstuk twee
beskyf die impak wat gestabiliseerde heelbloed het op die kliniese immunologie met
betrekking tot kwaliteit beheer en kwaliteit versekering. Die doelwit van hierdie studie
is om heelbloed te stabiliseer sodat die rakleeftyd meer as 30 dae is en sodoende as
verwysings-materiaal kontroles vir Suid Afrikaanse immunofenotipering kan dien. Dit
is ‘n verdere doelwit om hierdie tuis-gestabiliseerde kontrole monsters te gebruik as
“IQA” verwysings materiaal in verarmende Afrika lande. Die doelwit van hoofstuk
vier is om limfosiete te stimuleer om verskeie aktiverings merkers uit te druk op hul
selmembrane en dan te stabiliseer en dié te gebruik as Kwaliteits Kontroles vir die
meer gespesialiseerde immunologiese toetse.
Studie ontwerp: Hoofstuk drie beskryf ‘n aangepaste en verbeterde metode van heel
bloed stabiliseering. Stabiliteit word ondersoek in ‘n verskyndenheid konsentrasies van
‘n primêre stabiliseerings agent (chromium chloried heksahidraat) en inkubasie
periodes met paraformaldehied as tweede stabiliseerings agent word deeglik
gedokumenteer. Bloedmonsters van gesonde indiwidië (n=10) was gestabiliseer en
gemonitor vir roetine MIV membraanoppervlak antigene oor ‘n periode van 40 dae. Hierdie monsters (n=10) was gelees en geanaliseer op ‘n BD FACSCalibur™ en
vergelyk met ‘n BD FACSCount™ vloeisitometer instrument. Drie gestabiliseerde
heelbloed monsters (n=3) was gemonitor vir ‘n periode vir so lank moontlik die
fenotipiese selmembraan molekules identifiseerbaar was en die kwantiteit bepaalbaar
was. Hierdie drie monsters was gemeet op beide instrumente. As ‘n addisionele
doelwit, was hierdie drie gestabiliseerde monsters ondersoek om as moontlike
kalibrasie materiaal (verteenwoordig ‘n normale bloedmonster) te dien vir die BD
FACSCount™ instrument in die oggende voor pasiënt monsters gelees kan word.
In hoofstuk vier was limfosiete geϊsoleer en geaktiveer met ‘n verskyndenheid
stimulante om optimale aktiveerings-antigene uit te druk op T helper selmembrane
(byvoorbeeld CD25, CD69, HLA-DR en CD40 Ligand). Hierdie geaktiveerde
monsters was geanaliseer op die BD FACSCalibur™ en daarna gestabiliseer. Na
stabilisasie van die geaktiveerde limfosiet monsters was dit gemonitor oor ‘n tydperk
so lank moontlik data plotte leesbaar en selpopulasies identifiseerbaar was. Hierdie
monsters kan dien as ‘n moontlike “IQA” toets stel vir ‘n meer gespesialiseerde
immunologiese aktiveerings kontrole doeleindes.
Resultate: In hoofstuk drie; tien individiële gestabiliseerde heelbloed monsters het
gedui op geen-beduidende P waardes (P > 0.05) vir CD3, CD4 en CD8 persentasies en
absolute waardes; gemeet vanaf DAG 3 vergelykbaar tot-en-met DAG 40. Met korrelasie statistiek en vergelyking van die BD FACSCalibur™ met die
FACSCount™ instrumente, is die volgende opgemerk; R2 = 0.9848 vir die CD4
absolute waardes en ‘n R2 = 0.9636 vir die CD8 absolute waardes. Drie gestabiliseerde
monsters (n=3) was gemonitor vir MIV roetine fenotipeering tot en met DAG 84. Die
selpopulasies was duidelik identifiseerbaar en die kwantitatief meetbaar op albei
instrumente (BD FACSCalibur™ en BD FACSCount™).
Hoofstuk vier: geaktiveerde T helper lymphosiete het 25 – 35% membraan CD40
Ligand uitgedruk op hul selmembrane. Die stimulant van keuse was ionomysien teen
‘n optimale konsentrasie van 4μM. Die optimale inkubasie tydperk was vier ure by
37°C in 5% CO2 kondisie. Ses uur inkubasie in 4μM ionomysien by 37°C in ‘n 5%
CO2 omgewing was optimal vir die CD69 selmembraan uitdrukking en het 84.21%
opgelewer. Vir CD25 selmembraan uitdrukking was die selle vir ses ure met
phietoheamagglutinin (PHA) gestimuleer by 37°C in 5% CO2 kondisie en het 43%
CD25 selmembraan uitdrukking opgelewer. HLA-DR selmembraan uitdrukking: selle
was vir ses ure saam met PHA by 37°C in 5% CO2 kondisie inkubeer en het 43.32%
opgelewer. CD40 Ligand aktivering/gestabiliseerde limfosiete het tot en met dag 23
stabiliteit getoon. Die ligand was duidelik identifiseerbaar en kwantifiseerbaar.
Geaktiveerde lymphosiete wat CD69, CD25 en HLA-DR selmembraan merkers
uitdruk het na die stabiliseerings proses stabiliteit getoon tot-en-met dag 16. Gevolgtrekking: Die doel van hierdie studie was om verwysingskontroles voor te
berei sodat dit vars heelbloed naboots met uitkenbare eienskappe vir kliniese situasies.
‘n Toets kontrolestel met verwysings materiaal vir drie vlakke (byvoorbeeld ‘n lae,
medium en hoë kontrole) absolute selwaardes en persentasies kan voorberei word vir
roetine immunologiese fenotiperings merkers (CD3/CD4/CD8/CD45). Meer
gespesialiseerde kontrolestelle vir meer spesifieke doeleindes kan opgemaak word wat
‘n verskydenheid van limfosiet aktiveringsmerkers bevat met byvoorbeeld ‘n “nul”, lae
en hoë verwysings kontrole daarin. Hierdie heelbloed kan dien as “aktiveerde interne
kwaliteits verwysings materiaal” en kan gebruik word om nuut aangestelde
laboratorium werkers en nuut gekwalifiseerde studente op te lei. Hierdie verwysings
materiaal / kontroles kan aangewend word vir bevoegdheids doeleindes (byvoorbeeld
vir SANAS akkreditasie doeleindes), vir metode ontwikkeling, vir sagteware toetsing,
vir paneel opstelling en instrument verstellings doeleindes. Die kontroles moet ‘n
verskydenheid eienskappe bevat om effektief te wees. Byvoorbeeld, stabiliteit tydens
storing, gewenslik meer as ‘n paar weke, herhaalbaar en maklik handteerbaar. Hierdie
kontroles sal inligting voorsien op ‘n daaglikse basis tydens wisseling van tegnieke of
instrumentasie wat akuraatheid beinvloed en op die ou-end direk pasiënt versorging
bevoordeel.
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Modulação de eventos da imunidade humoral e celular por venenos brutos e componentes dos venenos de Bothrops jararacussu e Bothrops pirajai / Modulation of events of humoral and cellular immunity by crude venom and components of Bothrops jararacussu and Bothrops pirajaiAyres, Lorena Rocha 23 August 2010 (has links)
Serpentes do gênero Bothrops são responsáveis por 90% dos acidentes ofídicos no Brasil. Seus venenos provocam efeitos locais em humanos e animais, como hemorragia, edema, dor e necrose, caracterizando uma resposta inflamatória, cujo mecanismo não está bem definido. Esses efeitos estão relacionados com a ação combinada de proteases, substâncias que induzem hemorragia e fosfolipases, bem como a liberação de mediadores endógenos gerados pelos venenos. Considerando que a ativação do sistema complemento (SC) e de funções celulares, como quimiotaxia, ativação, proliferação e citotoxicidade podem desempenhar papel importante nos processos inflamatórios e de lesão tecidual subsequentes ao envenenamento, o estudo propõe: a) investigar a capacidade dos venenos brutos de serpentes Bothrops jararacussu e Bothrops pirajai e das toxinas purificadas, serinoprotease de B. jararacussu (SPBj) e L-aminoácido oxidase de B. pirajai (LAAOBp), em modular a atividade do SC; b) avaliar a contribuição do efeito sobre o SC no recrutamento de leucócitos polimorfonucleares humanos (PMN); c) avaliar o potencial citotóxico direto dos venenos e toxinas sobre células mononucleares do sangue periférico humano (PBMC); d) analisar o efeito dos venenos sobre a modulação da expressão dos marcadores de ativação CD69, CD25 e HLA-DR em células T, B e natural killer (NK). Os resultados do ensaio de citotoxicidade mostraram que o veneno bruto de B. jararacussu foi citotóxico para PBMC apenas nas concentrações maiores, de 50 e 100g/mL, não apresentando citotoxicidade nas outras concentrações testadas. A serinoprotease apresentou baixa citotoxicidade para essas células, o que sugere a necessidade de maiores investigações quanto aos mecanismos que levam a essa morte celular. O aumento da viabilidade celular encontrado nas amostras incubadas com veneno bruto e LAAO de B. pirajai sugere possível indução de proliferação celular, que necessita de maiores estudos. Os resultados obtidos sugerem que os venenos brutos de B. jararacussu e B. pirajai são capazes de ativar o SC como observado nos ensaios cinéticos da VCVL e VA e de quimiotaxia de neutrófilos, onde ficou evidenciado que a migração celular foi devida a liberação dos fatores quimiotáticos do SC, C3a e C5a. e que suas respectivas toxinas, serinoprotease e LAAO apresentam efeitos moduladores sobre o SC humano, e estimulam investigações mais aprofundadas com a finalidade de se esclarecer os mecanismos de ação e identificar os componentes responsáveis pelos efeitos observados. Houve expressão aumentada de CD69, CD25 e HLA-DR nas células T CD4+ e CD8+, especialmente quando incubadas com veneno bruto de B. jararacussu e LAAO de B. pirajai, o que reflete ativação da resposta imune celular, e pode sugerir que este tipo de resposta desempenhe papel relevante na indução e/ou controle dos processos imunopatológicos decorrentes de envenenamentos por B. jararacussu e B. pirajai. Esta investigação visa fornecer subsídios para a possível utilização das toxinas para fins terapêuticos e como ferramentas para investigação dos mecanismos envolvidos nos processos fisiopatológicos que ocorrem em decorrência de picadas e também em outras doenças de caráter inflamatório. / Snakes of the genus Bothrops are responsible for 90% of snakebites in Brazil. Their venoms cause local effects in humans and animals, such as hemorrhage, edema, pain and necrosis, characteristic of an inflammatory response. The mechanism is not well defined. These effects are related to the combined action of proteases, substances that induce bleeding and phospholipases, as well as release of endogenous mediators generated by the venoms. Considering that activation of the complement system (CS) and cellular functions such as chemotaxis, activation, proliferation and cytotoxicity, may play a role in inflammatory processes and tissue injury following envenomation, the study proposes: a) to investigate the ability of crude venom of B. jararacussu and B. pirajai and the purified toxins, serineprotease of B. jararacussu and L-amino acid oxidase (LAAO) of B pirajai in modulating the activity of the CS, b) to assess the contribution of the effect on CS in the recruitment of human polymorphonuclear leukocytes (PMN), c) to assess the direct cytotoxic potential of venoms and toxins on human peripheral blood mononuclear cells (PBMC), d) to analyse the effect of venoms on the modulation of the expression of activation markers CD69, CD25 and HLA-DR on T, B and natural killer (NK) cells. The results of cytotoxicity assay showed that the crude venom of B. jararacussu was cytotoxic to PBMC only at higher concentrations, 50 and 100g/mL, showing no cytotoxicity in the other concentrations. The serineprotease showed low cytotoxicity to the cells, suggesting the need for further investigations about the mechanisms that lead to this cell death. The increase in cell viability found in samples incubated with crude venom of B. pirajai and LAAO suggests the possibility of induction of cell proliferation, which needs further study. The results suggest that the crude venom of B. jararacussu and B. pirajai are capable of activating the CS as observed in kinetic assays of classical pathwaylectin pathway and alternative pathway and neutrophil chemotaxis assay, where it was shown that cell migration was due to release of CS chemotactic factors, C3a and C5a, and that their respective toxins, serineprotease and LAAO have modulatory effects on human CS, and stimulate further research in order to clarify the mechanisms of action and identify the components responsible for the observed effects. There was increased expression of CD69, CD25 and HLA-DR on CD4+ and CD8+, especially when incubated with crude venom of B. jararacussu and LAAO of B. pirajai. It reflects activation of cellular immune response and may suggest that this type of response play an important role in the induction and/or control of immunopathological processes arising from envenomation by B. jararacussu and B. pirajai. This research aims to provide subsidies to the possible use of the toxin for therapeutic purposes and as tools for investigating mechanisms involved in pathophysiological processes that occur as a result of snakebites and also in other diseases of inflammatory nature.
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Marcadores de ativação de linfócitos T e de suas citocinas como ferramentas diagnósticas na hipersensibilidade alérgica a fármacos / Markers of T lymphocyte activation and its cytokines as diagnostic tools in drug allergyTeixeira, Fabricia Martins January 2012 (has links)
TEIXEIRA, Fabrícia Martins. Marcadores de ativação de linfócitos T e de suas citocinas como ferramentas diagnósticas na hipersensibilidade alérgica a fármacos. 2012. 110 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Programa de Pós-Graduação em Biotecnologia, Rede Nordeste de Biotecnologia- Renorbio, Fortaleza-CE, 2012. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-05-23T12:51:39Z
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Previous issue date: 2012 / Drug allergy reactions represent one third of adverse drug reactions, and although they are infrequent, they present high rates of morbidity and mortality, revealing a major public health problem. The main challenges related to drug hypersensitivity result from its unpredictability, no animal model for research and individual variability with regard to drug metabolism. Drug allergy reactions are difficult to be diagnosed once there is a lack of laboratorial tests for their investigation. The present study aimed to establish some immunological in vitro methods for diagnosing drug allergy. Patients (n=20) attending a dermatology outpatient clinic, Hospital Universitario Walter Cantídio, Universidade Federal Ceara, with mucocutaneous and systemic manifestations due to drug hypersensitivity were investigated by clinical history, laboratory findings, and in vivo and in vitro tests. The lymphocyte activation markers, CD25 and CD69, were evaluated by flow cytometry on the peripheral blood mononuclear cells previously incubated with different concentrations of the suspected drug, and analysis of interferon γ and interleukin 5 was done in the culture supernatant by enzyme immunoassay. Eighteen patients were tested by skin tests; nine patients showed positive results to one or more drugs. Fifteen patients showed positivity for at least one of activation markers in response to the suspected drug. The markers CD69 and/or CD25 were expressed by T cells CD4+ and CD8+, both in immediate and delayed reactions. Comparing stimulation index of the markers between patients and healthy no allergic individuals, it was observed a significant difference for CD4+CD69+ in the three suspected drug concentrations and CD4+CD25+ only in the lower drug concentration. No significant differences were found for the cytokines IFN-γ and IL-5 between patients and healthy individuals. The detection of both activation markers CD69 and CD25 increased the diagnostic sensitivity of the test. The use of both markers represents a promising tool in drug allergy diagnosis. Nonetheless, this hypothesis needs to be confirmed with a greater number of patients and controls. / As reações alérgicas a fármacos representam um terço das reações adversas a medicamentos, e embora sejam pouco freqüentes, apresentam altas taxas de morbidade e mortalidade, revelando um importante problema de saúde pública. Os principais desafios relacionados com a hipersensibilidade a fármacos decorrem do fato de sua imprevisibilidade, de que não existe um modelo animal para pesquisa e devido à variabilidade individual no que diz respeito ao metabolismo do fármaco. As reações alérgicas a medicamentos são difíceis de serem diagnosticadas, uma vez que há carência de métodos laboratoriais para sua investigação. O presente estudo teve como objetivo estabelecer alguns métodos imunológicos in vitro para o diagnóstico de alergia a medicamentos. Vinte pacientes atendidos no Ambulatório de Dermatologia do Hospital Universitário Walter Cantídio, Universidade Federal do Ceará, com manifestações muco-cutâneas e sistêmicas decorrentes de hipersensibilidade a fármacos foram investigados através de história clínica, exames laboratoriais in vivo e in vitro. Foram avaliados os marcadores de ativação de linfócitos CD25 e CD69 através de citometria de fluxo, em células mononucleares do sangue periférico previamente incubadas com diferentes concentrações do fármaco suspeito, e análise das citocinas interferon γ e interleucina 5 no sobrenadante da cultura através de teste imunoenzimático. Dezoito pacientes foram submetidos aos testes cutâneos, sendo que nove mostraram resultados positivos a um ou mais fármacos. Quinze pacientes apresentaram positividade para pelo menos um dos marcadores de ativação em resposta ao fármaco suspeito. Os marcadores CD69 e/ou CD25 foram expressos pelas células T CD4+ e CD8+, tanto em reações imediatas como nas não imediatas. A comparação dos índices de estimulação desses marcadores entre pacientes e indivíduos saudáveis não alérgicos, resultou em diferença significativa para CD4+CD69+ nas três concentrações do fármaco suspeito e para CD4+CD25+ apenas na menor concentração do fármaco suspeito. Nenhuma diferença significativa para as citocinas IFN-γ e IL-5 foi observada entre os pacientes e os indivíduos controles. A detecção de ambos os marcadores de ativação CD69 e CD25 aumentou a sensibilidade diagnóstica do teste. O uso combinado dos marcadores representa uma ferramenta promissora no diagnóstico laboratorial das reações alérgicas a medicamentos. Não obstante, essa hipótese deve ser confirmada com um número maior de pacientes e controles.
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Modulação de eventos da imunidade humoral e celular por venenos brutos e componentes dos venenos de Bothrops jararacussu e Bothrops pirajai / Modulation of events of humoral and cellular immunity by crude venom and components of Bothrops jararacussu and Bothrops pirajaiLorena Rocha Ayres 23 August 2010 (has links)
Serpentes do gênero Bothrops são responsáveis por 90% dos acidentes ofídicos no Brasil. Seus venenos provocam efeitos locais em humanos e animais, como hemorragia, edema, dor e necrose, caracterizando uma resposta inflamatória, cujo mecanismo não está bem definido. Esses efeitos estão relacionados com a ação combinada de proteases, substâncias que induzem hemorragia e fosfolipases, bem como a liberação de mediadores endógenos gerados pelos venenos. Considerando que a ativação do sistema complemento (SC) e de funções celulares, como quimiotaxia, ativação, proliferação e citotoxicidade podem desempenhar papel importante nos processos inflamatórios e de lesão tecidual subsequentes ao envenenamento, o estudo propõe: a) investigar a capacidade dos venenos brutos de serpentes Bothrops jararacussu e Bothrops pirajai e das toxinas purificadas, serinoprotease de B. jararacussu (SPBj) e L-aminoácido oxidase de B. pirajai (LAAOBp), em modular a atividade do SC; b) avaliar a contribuição do efeito sobre o SC no recrutamento de leucócitos polimorfonucleares humanos (PMN); c) avaliar o potencial citotóxico direto dos venenos e toxinas sobre células mononucleares do sangue periférico humano (PBMC); d) analisar o efeito dos venenos sobre a modulação da expressão dos marcadores de ativação CD69, CD25 e HLA-DR em células T, B e natural killer (NK). Os resultados do ensaio de citotoxicidade mostraram que o veneno bruto de B. jararacussu foi citotóxico para PBMC apenas nas concentrações maiores, de 50 e 100g/mL, não apresentando citotoxicidade nas outras concentrações testadas. A serinoprotease apresentou baixa citotoxicidade para essas células, o que sugere a necessidade de maiores investigações quanto aos mecanismos que levam a essa morte celular. O aumento da viabilidade celular encontrado nas amostras incubadas com veneno bruto e LAAO de B. pirajai sugere possível indução de proliferação celular, que necessita de maiores estudos. Os resultados obtidos sugerem que os venenos brutos de B. jararacussu e B. pirajai são capazes de ativar o SC como observado nos ensaios cinéticos da VCVL e VA e de quimiotaxia de neutrófilos, onde ficou evidenciado que a migração celular foi devida a liberação dos fatores quimiotáticos do SC, C3a e C5a. e que suas respectivas toxinas, serinoprotease e LAAO apresentam efeitos moduladores sobre o SC humano, e estimulam investigações mais aprofundadas com a finalidade de se esclarecer os mecanismos de ação e identificar os componentes responsáveis pelos efeitos observados. Houve expressão aumentada de CD69, CD25 e HLA-DR nas células T CD4+ e CD8+, especialmente quando incubadas com veneno bruto de B. jararacussu e LAAO de B. pirajai, o que reflete ativação da resposta imune celular, e pode sugerir que este tipo de resposta desempenhe papel relevante na indução e/ou controle dos processos imunopatológicos decorrentes de envenenamentos por B. jararacussu e B. pirajai. Esta investigação visa fornecer subsídios para a possível utilização das toxinas para fins terapêuticos e como ferramentas para investigação dos mecanismos envolvidos nos processos fisiopatológicos que ocorrem em decorrência de picadas e também em outras doenças de caráter inflamatório. / Snakes of the genus Bothrops are responsible for 90% of snakebites in Brazil. Their venoms cause local effects in humans and animals, such as hemorrhage, edema, pain and necrosis, characteristic of an inflammatory response. The mechanism is not well defined. These effects are related to the combined action of proteases, substances that induce bleeding and phospholipases, as well as release of endogenous mediators generated by the venoms. Considering that activation of the complement system (CS) and cellular functions such as chemotaxis, activation, proliferation and cytotoxicity, may play a role in inflammatory processes and tissue injury following envenomation, the study proposes: a) to investigate the ability of crude venom of B. jararacussu and B. pirajai and the purified toxins, serineprotease of B. jararacussu and L-amino acid oxidase (LAAO) of B pirajai in modulating the activity of the CS, b) to assess the contribution of the effect on CS in the recruitment of human polymorphonuclear leukocytes (PMN), c) to assess the direct cytotoxic potential of venoms and toxins on human peripheral blood mononuclear cells (PBMC), d) to analyse the effect of venoms on the modulation of the expression of activation markers CD69, CD25 and HLA-DR on T, B and natural killer (NK) cells. The results of cytotoxicity assay showed that the crude venom of B. jararacussu was cytotoxic to PBMC only at higher concentrations, 50 and 100g/mL, showing no cytotoxicity in the other concentrations. The serineprotease showed low cytotoxicity to the cells, suggesting the need for further investigations about the mechanisms that lead to this cell death. The increase in cell viability found in samples incubated with crude venom of B. pirajai and LAAO suggests the possibility of induction of cell proliferation, which needs further study. The results suggest that the crude venom of B. jararacussu and B. pirajai are capable of activating the CS as observed in kinetic assays of classical pathwaylectin pathway and alternative pathway and neutrophil chemotaxis assay, where it was shown that cell migration was due to release of CS chemotactic factors, C3a and C5a, and that their respective toxins, serineprotease and LAAO have modulatory effects on human CS, and stimulate further research in order to clarify the mechanisms of action and identify the components responsible for the observed effects. There was increased expression of CD69, CD25 and HLA-DR on CD4+ and CD8+, especially when incubated with crude venom of B. jararacussu and LAAO of B. pirajai. It reflects activation of cellular immune response and may suggest that this type of response play an important role in the induction and/or control of immunopathological processes arising from envenomation by B. jararacussu and B. pirajai. This research aims to provide subsidies to the possible use of the toxin for therapeutic purposes and as tools for investigating mechanisms involved in pathophysiological processes that occur as a result of snakebites and also in other diseases of inflammatory nature.
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