Lymphocytes from patients with B-chronic lymphocytic leukemia (B-CLL) express large numbers of P2X7 receptors for extracellular adenosine triphosphate (ATP). Activation of P2X7 receptors induces multiple downstream effects, of which the best documented is the opening of an ionic channel that is selective for divalent cations. Another effect of ATP is to induce the shedding of L-selectin (CD62L), a molecule which is involved in the adhesive interactions of lymphocytes on endothelial cells. High levels of soluble L-selectin and CD23 are found in the serum of patients with B-CLL, although the mechanisms involved in their production are poorly characterized. Because extracellular ATP causes shedding of L-selectin, we studied the effect of ATP on shedding of CD23, an adhesion molecule expressed on the surface of B-CLL lymphocytes. ATP induced the shedding of CD23 at an initial rate of 12% of that for L-selectin, while the EC50 of ATP (35 uM) and BzATP (10 uM) was identical for shedding of both molecules. Inactivation of the P2X7 receptor by pre-incubation with OxATP, an irreversible inhibitor of P2X7 purinoceptor, abolished ATP-induced shedding of both molecules. Moreover, KN-62, the most potent inhibitor for the P2X7 receptor inhibited ATP-induced shedding of both CD23 and L-selectin with the same IC50 (12 nM). Ro 31-9790, a membrane permeant zinc chelator which inhibits the phorbol-ester stimulated shedding of L-selectin also inhibited shedding of CD23 from B-CLL lymphocytes, but the IC50 was different for the two shed molecules (25 versus 1 ug/ml respectively). Although L-selectin was completely shed by incubation of cells with phorbol-ester no CD23 was lost under these conditions. Also, Ca2+ inhibits ATP-induced CD23 shedding but not L-selectin shedding. Since soluble CD23 and L-selectin are found in the serum of normal subjects and B-CLL patients, the expression of these two adhesion molecules on lymphocytes before and after transendothelial migration was studied in an in vitro model of this process. In normal and B-CLL subjects, 71�b5% of L-selectin from both T and B cells and 90% of CD23 from B cells was lost following transmigration, while the expression of a range of other adhesion molecules such as VLA-4, ICAM-1, LFA-1 and CD44 was unchanged. Lymphocytes incubated with OxATP retained their capacity for transendothelial migration and showed the same loss of L-selectin as control leukaemic lymphocytes. Ro 31-9790, which can protect ATP-induced both L-selectin and CD23 shedding, had no effect on inhibiting L-selectin and CD23 lost during transmigration. These data show the presence of a second pathway for the downregulation of L-selectin and CD23 from the lymphocyte surface. Data in vivo from 'knock-out' mice show that L-selectin is essential for the emigration of lymphocytes through high endothelial venules into lymph nodes. The migration of normal and B-CLL lymphocytes across confluent human umbilical vein endothelial monolayers was studied in an in vitro model of this process. Lymphocytes treated with ATP or BzATP showed 56�b25% or 67�b16% loss of L-selectin on the surface and 36�b24% or 64�b19% decrease of transmigration, respectively, while OxATP, which does not alter the L-selectin level, had no effect on lymphocyte transmigration. Further experiments examined this correlation between L-selectin expression and lymphocyte transendothelial migration in this model system. A quantitative assay for cell surface L-selectin showed that expression of L-selectin was lower on B-CLL lymphocytes (8,880�b5,700 molecules/cell) than on normal lymphocytes (29,500�b7,500 molecules/cell, p less than 0.001). Also the rate of transmigration of B-CLL lymphocytes (1.5�b0.9 migrated cells/HUVEC) was lower than normal peripheral lymphocytes (2.4�b0.9 migrated cells/HUVEC, p=0.04). Incubation of lymphocytes in complete medium for 24 hrs increased the expression of L-selectin on B-CLL lymphocytes by 1.5 to 2 fold while the normal lymphocyte L-selectin remained at the initial level. This upregulation of B-CLL L-selectin correlated with a 2 fold increased rate of transendothelial migration. A correlation was found between L-selectin expression on lymphocytes and their ability for transendothelial migration (r^2=0.6). This study shows that the adhesion molecules L-selectin and CD23 can be lost from lymphocytes by two different physiological pathways. One is by P2X7 receptor activation by extracellular ATP while the second is activated by transendothelial migration of these cells. A second finding is that B-CLL lymphocytes have lower level of L-selectin expression and an impaired ability for transendothelial migration compared with normal peripheral blood lymphocytes. Do these results explain the high serum levels of soluble L-selectin and CD23 observed in B-CLL? Although B-CLL lymphocytes do not recirculate as rapidly as normal peripheral blood lymphocytes, the greatly increased number of leukaemic cells in B-CLL ensures that much more soluble L-selectin and CD23 is generated during the recirculation of these cells through the body.

Lymphocytes from patients with B-chronic lymphocytic leukemia (B-CLL) express large numbers of P2X7 receptors for extracellular adenosine triphosphate (ATP). Activation of P2X7 receptors induces multiple downstream effects, of which the best documented is the opening of an ionic channel that is selective for divalent cations. Another effect of ATP is to induce the shedding of L-selectin (CD62L), a molecule which is involved in the adhesive interactions of lymphocytes on endothelial cells. High levels of soluble L-selectin and CD23 are found in the serum of patients with B-CLL, although the mechanisms involved in their production are poorly characterized. Because extracellular ATP causes shedding of L-selectin, we studied the effect of ATP on shedding of CD23, an adhesion molecule expressed on the surface of B-CLL lymphocytes. ATP induced the shedding of CD23 at an initial rate of 12% of that for L-selectin, while the EC50 of ATP (35 uM) and BzATP (10 uM) was identical for shedding of both molecules. Inactivation of the P2X7 receptor by pre-incubation with OxATP, an irreversible inhibitor of P2X7 purinoceptor, abolished ATP-induced shedding of both molecules. Moreover, KN-62, the most potent inhibitor for the P2X7 receptor inhibited ATP-induced shedding of both CD23 and L-selectin with the same IC50 (12 nM). Ro 31-9790, a membrane permeant zinc chelator which inhibits the phorbol-ester stimulated shedding of L-selectin also inhibited shedding of CD23 from B-CLL lymphocytes, but the IC50 was different for the two shed molecules (25 versus 1 ug/ml respectively). Although L-selectin was completely shed by incubation of cells with phorbol-ester no CD23 was lost under these conditions. Also, Ca2+ inhibits ATP-induced CD23 shedding but not L-selectin shedding. Since soluble CD23 and L-selectin are found in the serum of normal subjects and B-CLL patients, the expression of these two adhesion molecules on lymphocytes before and after transendothelial migration was studied in an in vitro model of this process. In normal and B-CLL subjects, 71�b5% of L-selectin from both T and B cells and 90% of CD23 from B cells was lost following transmigration, while the expression of a range of other adhesion molecules such as VLA-4, ICAM-1, LFA-1 and CD44 was unchanged. Lymphocytes incubated with OxATP retained their capacity for transendothelial migration and showed the same loss of L-selectin as control leukaemic lymphocytes. Ro 31-9790, which can protect ATP-induced both L-selectin and CD23 shedding, had no effect on inhibiting L-selectin and CD23 lost during transmigration. These data show the presence of a second pathway for the downregulation of L-selectin and CD23 from the lymphocyte surface. Data in vivo from 'knock-out' mice show that L-selectin is essential for the emigration of lymphocytes through high endothelial venules into lymph nodes. The migration of normal and B-CLL lymphocytes across confluent human umbilical vein endothelial monolayers was studied in an in vitro model of this process. Lymphocytes treated with ATP or BzATP showed 56�b25% or 67�b16% loss of L-selectin on the surface and 36�b24% or 64�b19% decrease of transmigration, respectively, while OxATP, which does not alter the L-selectin level, had no effect on lymphocyte transmigration. Further experiments examined this correlation between L-selectin expression and lymphocyte transendothelial migration in this model system. A quantitative assay for cell surface L-selectin showed that expression of L-selectin was lower on B-CLL lymphocytes (8,880�b5,700 molecules/cell) than on normal lymphocytes (29,500�b7,500 molecules/cell, p less than 0.001). Also the rate of transmigration of B-CLL lymphocytes (1.5�b0.9 migrated cells/HUVEC) was lower than normal peripheral lymphocytes (2.4�b0.9 migrated cells/HUVEC, p=0.04). Incubation of lymphocytes in complete medium for 24 hrs increased the expression of L-selectin on B-CLL lymphocytes by 1.5 to 2 fold while the normal lymphocyte L-selectin remained at the initial level. This upregulation of B-CLL L-selectin correlated with a 2 fold increased rate of transendothelial migration. A correlation was found between L-selectin expression on lymphocytes and their ability for transendothelial migration (r^2=0.6). This study shows that the adhesion molecules L-selectin and CD23 can be lost from lymphocytes by two different physiological pathways. One is by P2X7 receptor activation by extracellular ATP while the second is activated by transendothelial migration of these cells. A second finding is that B-CLL lymphocytes have lower level of L-selectin expression and an impaired ability for transendothelial migration compared with normal peripheral blood lymphocytes. Do these results explain the high serum levels of soluble L-selectin and CD23 observed in B-CLL? Although B-CLL lymphocytes do not recirculate as rapidly as normal peripheral blood lymphocytes, the greatly increased number of leukaemic cells in B-CLL ensures that much more soluble L-selectin and CD23 is generated during the recirculation of these cells through the body.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-08-23T17:29:49Z No. of bitstreams: 1 texto completo.pdf: 983334 bytes, checksum: 7f0471578fe8924654865e3402110776 (MD5) / Made available in DSpace on 2017-08-23T17:29:49Z (GMT). No. of bitstreams: 1 texto completo.pdf: 983334 bytes, checksum: 7f0471578fe8924654865e3402110776 (MD5) Previous issue date: 2017-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neutrófilos são as primeiras células do sistema imune a migrarem para o tecido inflamado e exercem a importante função de fagocitose e eliminação imediata de patógenos invasores. A ativação de neutrófilos é um processo de múltiplos passos e de alta complexidade. A busca por agentes biológicos capazes de modular o processo de ativação, migração, fagocitose e produção de espécies reativas de oxigênio (ROS) é importante pois aumentam a gama de opções para utilização na pesquisa. Nesse trabalho utilizamos a lectina extraída de Brassica oleracea (BOL) a fim de avaliar a sua capacidade na modulação da resposta de neutrófilos. Para os ensaios nós purificamos neutrófilos de camundongo tanto do sangue periférico quanto da cavidade peritoneal buscando avaliar sua capacidade migratória, o índice de CD62L na superfície e o índice fagocítico de neutrófilos pré-incubados com BOL. A lectina apresentou diversos efeitos de acordo com a dose utilizada, sendo possível observar o efeito de indução de migração para cavidade peritoneal de camundongos quando utilizada em doses intermediárias (1 μg/mL e 2,5 μg/mL) tanto quanto o efeito de redução de migração quando observada em doses altas (5 μg/mL e 10 μg/mL). O índice de fagocitose também foi avaliado e houve alteração de acordo também com a dose utilizada. As doses mais altas apresentaram efeito de redução na taxa de fagocitose (5 μg/mL e 10 μg/mL) enquanto as outras doses não apresentavam diferença estatística. Com esse trabalho conseguimos observar os efeitos imunomodulatórios sobre neutrófilos de uma lectina ainda muito pouco estudada e que demonstrou ter efeitos sobre a fisiologia de neutrófilos de acordo com a dose escolhida, alterando sua capacidade de migração e fagocitose. / Neutrophils are the first cells of the immune system to migrate into inflamed tissue and they develop the important function of phagocytosis and immediate elimination of invading pathogens. Neutrophil activation is a multi-step and highly complex process. Research on biological agents able to modulate the activation, migration, phagocytosis and production of reactive oxygen species (ROS) are important because they increase the range of options for use in the research. In this work we used the lectin extracted from Brassica oleracea (BOL) aiming to evaluate its ability to modulate the neutrophil response. For the tests, we purified mouse neutrophils from the peripheral blood and the peritoneal cavity with the objective to evaluate their migratory capacity, the surface CD62L index and the phagocytic index of neutrophils pre-incubated with BOL. The lectin presented several effects according to the dose used, being possible to observe the effect of induction of migration to peritoneal cavity when it was used in intermediate doses (1 μg/mL and 2.5 μg/mL) as well as the effect of reduction of migration as observed at high doses (5 μg/ mL and 10 μg/mL). The phagocytosis index was also evaluated and there was also an alteration according to the dose used. Higher doses showed a smaller phagocytosis rate (5 μg/mL and 10 μg/mL), unlike the other doses. In this work we were able to observe the immunomodulatory effects on neutrophils of a lectin that has not yet been studied and has shown to have effects on neutrophil physiology according to the chosen dose, altering its migration capacity and phagocytosis.

Humane NK Zellen können in CD56br und CD56dim NK Zellen unterteilt werden. In dieser Arbeit wurde untersucht, in welchem Zusammenhang die verschiedenen NK Zell Populationen stehen und wie funktional kompetente NK Zellen generiert werden. Des Weiteren wurde die Heterogenität der CD56dim NK Zell Population in Bezug auf Funktionalität und Differenzierungsstadien analysiert. Es konnte gezeigt werden, dass CD56br NK Zellen in CD56dim NK Zellen differenzieren. Währenddessen werden u.a. MHC-I spezifische inhibierende Rezeptoren (KIR) erworben. Diese sind essentiell für die Unterscheidung zwischen “Selbst” und “Nicht-Selbst”, wobei nur NK Zellen, die Selbst-MHC-spezifische KIRs tragen, funktional kompetent sind. In der vor-liegenden Arbeit konnte darüber hinaus gezeigt werden, dass zuvor anerge NK Zellen nach Zytokin-induzierter Expression eines Selbst-MHC-spezifischen KIRs kompetent werden. Ex vivo Analysen humaner Gewebe lassen vermuten, dass diese Prozesse während einer Entzündung in sekundären lymphatischen Organen (SLO) stattfinden könnten. Auch CD56dim NK Zellen selbst sind nicht homogen, hingegen können anhand der Expression von KIRs oder CD62L, welches für die Migration in SLO wichtig ist, weitere Subpopulationen unterschieden werden. Eine umfassende Analyse bezüglich KIR und CD62L Expression führte zur Identifizierung einer zuvor nicht charakterisierten CD56dimCD62L+ NK Zell Population, welche die Fähigkeiten von CD56br, Zytokine zu produzieren und zu proliferieren, mit einem hohen zytotoxischen Potenzial, vereinigt. Weitere ex vivo Untersuchungen des Phänotyps, der Telomerlängen und der Verteilung in Relation zum Alter lassen vermuten, dass die Differenzierung humaner NK Zellen von CD56br über CD56dimCD62L+ zu CD56dimCD62L- verläuft, wobei die Zellen mit fortschreitender Dif-ferenzierung ihre Fähigkeit auf Zytokine zu antworten verlieren und dafür die Fähigkeit er-langen, über aktivierende Rezeptoren stimuliert zu werden. / Human NK cells comprise two main subsets, CD56br and CD56dim cells. In this study, an extensive analysis of human NK cell phenotype and functional characteristics has been performed in order to investigate the developmental relation between NK cell subsets, to elucidate how NK cell competence is acquired and to further dissect the heterogeneity of the CD56dim subset with regard to functions and differentiation history of human NK cells. It could be shown that upon cytokine activation, CD56br differentiate into CD56dim NK cells and that this process might take place in inflamed secondary lymphoid organs (SLO). One of the crucial markers acquired during this process is KIR, the main MHC-specific inhibitory receptors responsible for self versus non self recognition. Previously, it has been shown that only cells expressing self-MHC specific KIRs are responsive to activating stimuli. In this study, it was demonstrated that induction of self-MHC specific KIR by cytokines leads to acquisition of functional competence. Ex vivo analysis of human tissues suggests that acquisition of KIR and consequently of cytotoxic competence may occur in inflamed SLO. Finally, it was demonstrated that CD56dim NK cells do not represent a homogenous population. When dissected for CD62L and KIR expression, a new subset of NK cells could be identified, namely CD56dimCD62L+, which uniquely combines properties of CD56br NK cells, particularly high IFN-g production upon cytokine stimulation, proliferation and potential to migrate into SLO, with the capacity of CD56dim to kill, produce cytokines upon activating receptor stimulation and to migrate into inflamed tissues. Ex vivo analysis of the function, phenotype, telomere length and frequencies during ageing of CD56br, CD56dimCD62L+ and CD56dimCD62L- NK cells suggest that CD56dimCD62L+ cells represent an intermediate stage of NK cell maturation between the more immature CD56br and the terminally differentiated CD56dim CD62L- NK cells.

IntroduÃÃo â AlteraÃÃes na expressÃo ou funÃÃo das molÃculas de adesÃo (MA) nas cÃlulas leucÃmicas podem contribuir para a evoluÃÃo e no comportamento biolÃgico das leucemias agudas. A expressÃo aumentada nas LLAs parece relacionar-se aos mecanismos de disseminaÃÃo extramedular dos linfoblastos, infiltraÃÃo do SNC e formaÃÃo de massas tumorais. Objetivos â Analisar a expressÃo da L-selectina e do CD44 nas LLAs em crianÃas e adolescentes. Avaliar os fatores prognÃsticos (idade, sexo, leucometria ao diagnÃstico, imunofenÃtipo, classificaÃÃo FAB, EGIL, Ãndice de DNA e resposta ao tratamento de induÃÃo) e as apresentaÃÃes extramedulares das LLAs e correlacionÃ-los com essas MA. Pacientes e MÃtodos â Foram avaliados 76 pacientes com LLA, tratados com o Protocolo GBTLI-LLA. O diagnÃstico foi baseado em critÃrios FAB, imunofenotÃpicos (EGIL) e citogenÃticos. A expressÃo das MA foi avaliada por citometria de fluxo, utilizando tripla marcaÃÃo. O anticorpo monoclonal CD45-PerCP (ImmunotechÂ) foi utlizado como marcador dos linfoblastos. O CD44-PE (Clone HP2/9 - ImmunostepÂ) e o CD62L-FITC (Clone HI62L - ImmunostepÂ) foram utilizados para a marcaÃÃo das MA. Para a anÃlise das amostras e o cÃlculo da intensidade mÃdia de fluorescÃncia foi utilizado o programa Cell Quest. Na anÃlise estatÃstica utilizou-se o software SPSS 16.0. A associaÃÃo entre as variÃveis, os fatores prognÃsticos e resposta foi realizada com os testes de Qui-quadrado, exato de Fisher e Mann-Whitney. Sobrevida global foi determinada por curvas Kaplan-Meier e teste log-rank. AnÃlise multivariada por modelo proporcional de Cox foi utilizada para assegurar a independÃncia dos fatores prognÃsticos. Resultados â A mÃdia de idade foi 6,3Â0,5 anos (5m -17a) e predominou o sexo masculino (65%). Ao diagnÃstico os achados clÃnicos foram: hepatomegalia (63%), esplenomegalia (58%) e linfadenomegalia (44%). A infiltraÃÃo SNC ocorreu em 6,6% dos casos e o alargamento de mediastino em 11,8%. Quanto ao risco, 54% eram baixo risco e 46% alto risco. A classificaÃÃo FAB determinou 83% como L1 e 17% L2. DiagnÃstico de LLA-B foi mais frequente (89,5%) e o da LLA-T em 10,5% dos pacientes. O subtipo EGIL mais prevalente foi B II e B III, 51,5% e 45% respectivamente. O IDNA &#8805; 1.16 foi encontrado em 19% dos pacientes e associou-se a bom prognÃstico. Na avaliaÃÃo do D8, 95% dos pacientes apresentaram contagem de blastos <1000/mm3 e leucÃcitos < 5.000/mm3. A taxa de remissÃo de induÃÃo foi de 95% e ocorreram 2,6% de Ãbitos na induÃÃo. Observou-se uma maior expressÃo do CD44 na LLA-T (87,5%/ IMF=150,44Â20,29), porÃm sem significÃncia estatÃstica. LLAs com massa tumoral apresentaram 84% de expressÃo do CD44, quando comparada a 52% das LLAs sem massa tumoral (p=0.01; OR=4,8). ExpressÃo aumentada da L-selectina na LLA-T (87,5%/IMF=272,33Â52,72) foi estatisticamente significante (p=0,004), comparado a LLA-B (54,5%/ IMF= 115,90Â12,75). NÃo houve correlaÃÃo entre os outros fatores prognÃsticos e essas MA. Na anÃlise multivariada as variÃveis de maior impacto para a sobrevida foram: a leucometria ao diagnÃstico, sexo, imunofenÃtipo T e a L-selectina. ConclusÃo â A expressÃo da L-selectina e do CD44 estÃo aumentadas nas LLAs estudadas, principalmente na LLA-T. O CD44 correlacionou-se com LLAs com massas tumorais e parece estar relacionado aos mecanismos de disseminaÃÃo extramedular dos linfoblastos / Introduction â Altered expression or function of adhesion molecules on leukemic blasts may contribute to the evolution of acute leukemia and its biological behavior. The elevated expression of adhesion molecules in ALL might be correlated with the extramedullary dissemination of blast cells, CNS involvement and leukemia tumor burden. Purpose â To analyze the expression of L-selectin and CD44 in ALL in children and adolescents. As well as to evaluate the prognostic factors (age, gender, initial leukocyte count, immunophenotype, FAB and EGIL classification, DNA index and early response to treatment) and the extramedullary presentation of ALL, to finally correlate the prognostic factors with these adhesion molecules. Patients and Methods â From November 2007 to November 2008, 76 patients with newly diagnosed ALL started on Brazilian GBTLI-ALL Protocol. The diagnosis was based on cytological, immunophenotypic, and cytogenetic methods. The mean fluorescence intensity (MFI) and the percentage of the adhesion molecules blasts cells was measured by flow cytometry using triple staining with McAb directly conjugated. CD45-PerCP positive cells were gated for blasts analysis. Anti-CD44-PE (Clone HP2/9 - ImmunostepÂ) and CD62L-FITC (Clone HI62L - ImmunostepÂ) were used to mark the adhesion molecules. The Cell Quest program was used for data acquisition and analysis. Statistical analysis was done by SPSS 16.0 Software. The association of features, prognosis and response to treatment was assessed by Chi-square, Fisher exact and Mann-Whitney tests. Overall survival curves were constructed by the Kaplan-Meier method and the log-rank test. Multivariate Cox regression analysis showed independent prognostic factors. Results â The mean age at diagnosis was 6.3Â0.5 years (range 9mo to 17yr) and 65% of them were boys. Clinical findings were hepatomegaly (63%), splenomegaly (58%), lymphadenopathy (44%). CNS involvement was detected in 6.6% of cases and mediastinal mass appeared in 11.8% of them. Patients were classified into low risk (54%) and high risk (46%). FAB classification identified 83% as L1 and 17% as L2. Immunophenotypically, 89.5% of patients were classified as B-lineage ALL and 10.5% as T-lineage ALL. The most frequent EGIL subtype was B common and pre-B-ALL (51.5% and 45.5%, respectively). DNA index greater than 1.16 was found in 19% of the patients and was associated with favorable prognosis. On the D8 evaluation, 95% of the patients had blast count lower than 1.000/mm3 and leukocyte count lower than 5.000/mm3. The remission induction rate was 95% and there was a rate of 2.6% of death during induction therapy. CD44 had greater expression to the rate of 87.5% in T-cell ALL (MFI=150.44Â20.29) with no statistical correlation. A significant positive correlation was demonstrated between 84% of CD44 expression and Leukemia burden tumor cases (p=0.01; OR=4.8). There was statistical correlation between L-selectin expression (87.5%/MFI=272.33Â52.72) and T-cell ALL (p=0,004). No significant correlation was detected between L-selectin and CD44 expression and other prognostic factors. Multivariate statistical analysis (adjusted for overall survival) indicated that initial leukocyte count, gender, T immunophenotype and L-selectin were independent factors. Conclusion â L-selectin and CD44 expressions were elevated in ALL studied, mainly in T-cell ALL. The research demonstrated that there is an association between CD44 expression and leukemia tumor burden, which might be involved in the dissemination of leukemic cells and the progression of the disease.

A icterícia por hiperbilirrubinemia indireta afeta mais de 60% dos recém-nascidos a termo. O tratamento, quando necessário, é realizado através da fototerapia. Não existem estudos na literatura avaliando os efeitos da fototerapia na função dos neutrófilos de recém-nascidos. O melhor entendimento da função dos neutrófilos nos recém-nascidos antes e após a fototerapia seria importante para avaliar as possíveis repercussões na expressão dos neutrófilos desencadeadas pelo tratamento fototerápico. O objetivo deste estudo foi avaliar e comparar a função dos neutrófilos, através da mensuração pela citometria de fluxo da expressão dos principais marcadores de superfície em recémnascidos ictéricos, antes e após 24 horas de fototerapia. Metodologia: Foram incluídos recém-nascidos com idade gestacional ≥ 35 semanas e peso de nascimento ≥ 2000g, que possuiam critérios da Academia Americana de Pediatria para tratamento fototerápico. Os critérios de exclusão foram: mal-formações congênitas, síndromes com alterações cromossômicas, erro inato do metabolismo, infecções do grupo STORCH, asfixia neonatal, sepse ou suspeita de sepse, exsanguineotransfusão, transfusão de hemocomponentes e uso de imunoglobulina. Foi realizada a avaliação de expressão da intensidade média de fluorescência (IMF) de CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 e CD66, antes do início e após 24 horas do início da fototerapia. Foram utilizados o teste T de Student para análise dos dados. Resultados: Foram incluídos 25 recém-nascidos no estudo, com idade mediana de 53 (27.5-75.5) horas de vida e bilirrubina média de 13.6±2.85 mg/dL. Não houve diferença estatística na expressão de CD11b, CD15, CD18, CD62L, CD64 e percentual de neutrófilos antes e após 24 horas de fototerapia. Ocorreu aumento da expressão de CD10 8 (p=0.038) e CD16 (p=0.017) e redução da expressão de CD11c (p=0.023) e CD66acde (p=0.004) após 24 horas de fototerapia. Conclusão: Os recém-nascidos submetidos ao tratamento fototerápico apresentaram aumento da expressão de CD10 e de CD16 e diminuição da expressão de CD11c e de CD66acde após 24 horas de exposição, que pode estar relacionado a um efeito antiinflamatório da fototerapia nos recém-nascidos expostos a este tratamento. / Jaundice due to indirect hyperbilirubinemia affects more than 60% of term neonates. The treatment when necessary is carried out using phototherapy. There are no studies in the literature evaluating the effect of phototherapy on the function of neonates' neutrophils. A better understanding of the function of neutrophils in neonates before and after phototherapy would be important in order to assess potential effects on the expression of neutrofils triggered by the phototherapy treatment. The aim of this study was to assess and compare the function of neutrophils by measuring the expression of the main surface markers in icteric neonates, using flow cytometry, before and after 24 hours of phototherapy. Methodology: Neonates at a gestational age ≥ 35 weeks and at a birth weight ≥ 2000g who met the criteria of the American Academy of Pediatrics for phototherapy were included. The exclusion criteria were: congenital malformations, syndromes with chromosomal alterations, inborn errors of metabolism, infections of the STORCH group, neonatal asphyxia, sepsis or suspicion of sepsis, exchange transfusion, transfusion of blood components, and use of immunoglobulin. The evaluation of the MFI expression of CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 and CD66 was performed before and 24 hours after the initiation of phototherapy. The chi-square and Student T tests were used for data analysis. Results: Twenty-five neonates were included in the study at the mean age of 53 (27.5- 75.5) hours of life and with a mean bilirubin level of 13.6±2.85 mg/dL. There was no statistical difference in the expression of CD11b, CD15, CD18, CD62L, CD64 and percentage of neutrophils before and after 24 hours of phototherapy. There was an increase in the expression of CD10 (p=0.038) and CD16 (p=0.017) and a reduction in 10 the expression of CD11c (p=0.023) and CD66acde (p=0.004) after 24 hours of phototherapy. Conclusion: The newborns submitted to phototherapy had increased expression of CD10 and CD16 and decreased expression of CD11c and CD66acde after 24 hours of exposure, which may be related to an anti-inflammatory effect of phototherapy on the neonates exposed to this treatment.

A icterícia por hiperbilirrubinemia indireta afeta mais de 60% dos recém-nascidos a termo. O tratamento, quando necessário, é realizado através da fototerapia. Não existem estudos na literatura avaliando os efeitos da fototerapia na função dos neutrófilos de recém-nascidos. O melhor entendimento da função dos neutrófilos nos recém-nascidos antes e após a fototerapia seria importante para avaliar as possíveis repercussões na expressão dos neutrófilos desencadeadas pelo tratamento fototerápico. O objetivo deste estudo foi avaliar e comparar a função dos neutrófilos, através da mensuração pela citometria de fluxo da expressão dos principais marcadores de superfície em recémnascidos ictéricos, antes e após 24 horas de fototerapia. Metodologia: Foram incluídos recém-nascidos com idade gestacional ≥ 35 semanas e peso de nascimento ≥ 2000g, que possuiam critérios da Academia Americana de Pediatria para tratamento fototerápico. Os critérios de exclusão foram: mal-formações congênitas, síndromes com alterações cromossômicas, erro inato do metabolismo, infecções do grupo STORCH, asfixia neonatal, sepse ou suspeita de sepse, exsanguineotransfusão, transfusão de hemocomponentes e uso de imunoglobulina. Foi realizada a avaliação de expressão da intensidade média de fluorescência (IMF) de CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 e CD66, antes do início e após 24 horas do início da fototerapia. Foram utilizados o teste T de Student para análise dos dados. Resultados: Foram incluídos 25 recém-nascidos no estudo, com idade mediana de 53 (27.5-75.5) horas de vida e bilirrubina média de 13.6±2.85 mg/dL. Não houve diferença estatística na expressão de CD11b, CD15, CD18, CD62L, CD64 e percentual de neutrófilos antes e após 24 horas de fototerapia. Ocorreu aumento da expressão de CD10 8 (p=0.038) e CD16 (p=0.017) e redução da expressão de CD11c (p=0.023) e CD66acde (p=0.004) após 24 horas de fototerapia. Conclusão: Os recém-nascidos submetidos ao tratamento fototerápico apresentaram aumento da expressão de CD10 e de CD16 e diminuição da expressão de CD11c e de CD66acde após 24 horas de exposição, que pode estar relacionado a um efeito antiinflamatório da fototerapia nos recém-nascidos expostos a este tratamento. / Jaundice due to indirect hyperbilirubinemia affects more than 60% of term neonates. The treatment when necessary is carried out using phototherapy. There are no studies in the literature evaluating the effect of phototherapy on the function of neonates' neutrophils. A better understanding of the function of neutrophils in neonates before and after phototherapy would be important in order to assess potential effects on the expression of neutrofils triggered by the phototherapy treatment. The aim of this study was to assess and compare the function of neutrophils by measuring the expression of the main surface markers in icteric neonates, using flow cytometry, before and after 24 hours of phototherapy. Methodology: Neonates at a gestational age ≥ 35 weeks and at a birth weight ≥ 2000g who met the criteria of the American Academy of Pediatrics for phototherapy were included. The exclusion criteria were: congenital malformations, syndromes with chromosomal alterations, inborn errors of metabolism, infections of the STORCH group, neonatal asphyxia, sepsis or suspicion of sepsis, exchange transfusion, transfusion of blood components, and use of immunoglobulin. The evaluation of the MFI expression of CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 and CD66 was performed before and 24 hours after the initiation of phototherapy. The chi-square and Student T tests were used for data analysis. Results: Twenty-five neonates were included in the study at the mean age of 53 (27.5- 75.5) hours of life and with a mean bilirubin level of 13.6±2.85 mg/dL. There was no statistical difference in the expression of CD11b, CD15, CD18, CD62L, CD64 and percentage of neutrophils before and after 24 hours of phototherapy. There was an increase in the expression of CD10 (p=0.038) and CD16 (p=0.017) and a reduction in 10 the expression of CD11c (p=0.023) and CD66acde (p=0.004) after 24 hours of phototherapy. Conclusion: The newborns submitted to phototherapy had increased expression of CD10 and CD16 and decreased expression of CD11c and CD66acde after 24 hours of exposure, which may be related to an anti-inflammatory effect of phototherapy on the neonates exposed to this treatment.

A icterícia por hiperbilirrubinemia indireta afeta mais de 60% dos recém-nascidos a termo. O tratamento, quando necessário, é realizado através da fototerapia. Não existem estudos na literatura avaliando os efeitos da fototerapia na função dos neutrófilos de recém-nascidos. O melhor entendimento da função dos neutrófilos nos recém-nascidos antes e após a fototerapia seria importante para avaliar as possíveis repercussões na expressão dos neutrófilos desencadeadas pelo tratamento fototerápico. O objetivo deste estudo foi avaliar e comparar a função dos neutrófilos, através da mensuração pela citometria de fluxo da expressão dos principais marcadores de superfície em recémnascidos ictéricos, antes e após 24 horas de fototerapia. Metodologia: Foram incluídos recém-nascidos com idade gestacional ≥ 35 semanas e peso de nascimento ≥ 2000g, que possuiam critérios da Academia Americana de Pediatria para tratamento fototerápico. Os critérios de exclusão foram: mal-formações congênitas, síndromes com alterações cromossômicas, erro inato do metabolismo, infecções do grupo STORCH, asfixia neonatal, sepse ou suspeita de sepse, exsanguineotransfusão, transfusão de hemocomponentes e uso de imunoglobulina. Foi realizada a avaliação de expressão da intensidade média de fluorescência (IMF) de CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 e CD66, antes do início e após 24 horas do início da fototerapia. Foram utilizados o teste T de Student para análise dos dados. Resultados: Foram incluídos 25 recém-nascidos no estudo, com idade mediana de 53 (27.5-75.5) horas de vida e bilirrubina média de 13.6±2.85 mg/dL. Não houve diferença estatística na expressão de CD11b, CD15, CD18, CD62L, CD64 e percentual de neutrófilos antes e após 24 horas de fototerapia. Ocorreu aumento da expressão de CD10 8 (p=0.038) e CD16 (p=0.017) e redução da expressão de CD11c (p=0.023) e CD66acde (p=0.004) após 24 horas de fototerapia. Conclusão: Os recém-nascidos submetidos ao tratamento fototerápico apresentaram aumento da expressão de CD10 e de CD16 e diminuição da expressão de CD11c e de CD66acde após 24 horas de exposição, que pode estar relacionado a um efeito antiinflamatório da fototerapia nos recém-nascidos expostos a este tratamento. / Jaundice due to indirect hyperbilirubinemia affects more than 60% of term neonates. The treatment when necessary is carried out using phototherapy. There are no studies in the literature evaluating the effect of phototherapy on the function of neonates' neutrophils. A better understanding of the function of neutrophils in neonates before and after phototherapy would be important in order to assess potential effects on the expression of neutrofils triggered by the phototherapy treatment. The aim of this study was to assess and compare the function of neutrophils by measuring the expression of the main surface markers in icteric neonates, using flow cytometry, before and after 24 hours of phototherapy. Methodology: Neonates at a gestational age ≥ 35 weeks and at a birth weight ≥ 2000g who met the criteria of the American Academy of Pediatrics for phototherapy were included. The exclusion criteria were: congenital malformations, syndromes with chromosomal alterations, inborn errors of metabolism, infections of the STORCH group, neonatal asphyxia, sepsis or suspicion of sepsis, exchange transfusion, transfusion of blood components, and use of immunoglobulin. The evaluation of the MFI expression of CD10, CD11b, CD11c, CD15, CD16, CD18, CD62L, CD64 and CD66 was performed before and 24 hours after the initiation of phototherapy. The chi-square and Student T tests were used for data analysis. Results: Twenty-five neonates were included in the study at the mean age of 53 (27.5- 75.5) hours of life and with a mean bilirubin level of 13.6±2.85 mg/dL. There was no statistical difference in the expression of CD11b, CD15, CD18, CD62L, CD64 and percentage of neutrophils before and after 24 hours of phototherapy. There was an increase in the expression of CD10 (p=0.038) and CD16 (p=0.017) and a reduction in 10 the expression of CD11c (p=0.023) and CD66acde (p=0.004) after 24 hours of phototherapy. Conclusion: The newborns submitted to phototherapy had increased expression of CD10 and CD16 and decreased expression of CD11c and CD66acde after 24 hours of exposure, which may be related to an anti-inflammatory effect of phototherapy on the neonates exposed to this treatment.