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1.
Biomolecules ; 13(6)2023 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-37371554

RESUMO

Interleukin 10 (IL-10) plays a role in inflammation and cell-type responses. The anti-SS-A/Ro antibody contributes to leucopenia, and cutaneous and neonatal lupus. OBJECTIVES: To evaluate the association between serum IL-10 levels and autoantibodies, disease activity and organ involvement in systemic lupus erythematosus (SLE) patients. PATIENTS AND METHODS: We studied 200 SLE patients and 50 controls. We analyzed organ involvement, disease activity, serum IL-10 and interleukin-6 (IL-6) levels, and antinuclear and antiphospholipid antibody profiles. RESULTS: Serum IL-10 and IL-6 levels were higher in SLE patients than in controls (all p < 0.00001). Serum IL-10 levels were positively correlated with IL-6 (p < 0.00001), CRP (p < 0.00001), fibrinogen (p = 0.003), and ESR (p < 0.00001), and negatively correlated with hemoglobin (p = 0.0004) and lymphocytes (p = 0.01). Serum IL-6 levels were positively correlated with CRP (p < 0.00001), fibrinogen (p = 0.001), and ESR (p < 0.00001); and negatively correlated with hemoglobin (p = 0.008) and lymphocytes (p = 0.03). Elevated serum IL-10 levels were associated with an increased risk of anti-SS-A/Ro antibody positivity (p = 0.03). Elevated serum IL-6 levels were associated with an increased risk of heart (p = 0.007) and lung (p = 0.04) involvement. CONCLUSIONS: In SLE patients, increased serum IL-10 levels were associated with increased disease activity and risk of anti-SS-A/Ro antibody positivity.


Assuntos
Autoanticorpos , Interleucina-10 , Interleucina-6 , Lúpus Eritematoso Sistêmico , Humanos , Recém-Nascido , Autoanticorpos/imunologia , Interleucina-10/sangue , Interleucina-10/imunologia , Interleucina-6/sangue , Interleucina-6/imunologia , Leucopenia/sangue , Leucopenia/imunologia , Lúpus Eritematoso Sistêmico/imunologia
2.
Int Immunopharmacol ; 101(Pt A): 108292, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34710846

RESUMO

Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.


Assuntos
Ciclofosfamida/efeitos adversos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Leucopenia/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Receptores de Antígenos de Linfócitos B/efeitos dos fármacos , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Regiões Determinantes de Complementaridade/efeitos dos fármacos , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/metabolismo , Ciclofosfamida/uso terapêutico , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Cadeias Pesadas de Imunoglobulinas/efeitos dos fármacos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Região de Junção de Imunoglobulinas/efeitos dos fármacos , Região de Junção de Imunoglobulinas/metabolismo , Região Variável de Imunoglobulina/efeitos dos fármacos , Região Variável de Imunoglobulina/metabolismo , Leucócitos/efeitos dos fármacos , Leucopenia/induzido quimicamente , Leucopenia/tratamento farmacológico , Linfócitos/metabolismo , Camundongos Endogâmicos BALB C , Receptores de Antígenos de Linfócitos B/imunologia
3.
Medicine (Baltimore) ; 100(21): e25985, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34032713

RESUMO

ABSTRACT: Cytopenias in systemic lupus erythematosus (SLE) require clinical and laboratory workup and bone marrow (BM) examination to determine the cause and for appropriate patient management. Common causes include an increase in SLE activity, immune-mediated hemolysis, iron deficiency, antiphospholipid antibody syndrome, infection, or the effect of medications. We retrospectively evaluated the clinical and laboratory findings of patients with SLE and cytopenias who had undergone BM studies to determine the indicators of malignancy.We retrospectively reviewed medical records of patients with SLE who presented with cytopenias for their disease course, medications, laboratory parameters and documented the spectrum of morphological changes in BM including CD34 expression.Twenty patients with SLE had undergone BM biopsy for evaluation of cytopenias. 14/20 (70%) of the patients had reactive BM, and the rest had hematologic malignancies involving the BM. Of these 14 patients, 8 had hypocellular marrow with loss of precursor cells (low CD34), 4 had left shift in myeloid lineage, 3 had serous atrophy, and 1had multilineage dysplasia. The 6 patients with hematologic malignancies included 2 with diffuse large B cell lymphoma, and one each of natural killer/T cell lymphoma, post-transplant lymphoproliferative disorder, Hodgkin lymphoma, and myelodysplastic syndrome evolving to acute myelogenous leukemia. The presence of autoantibodies, SLE activity, and lupus nephritis were comparable in patients with and without neoplasia. However, the duration of the use of multiple immunosuppressants, years since renal transplant (22 vs 10), multiple transplants, and the presence of other autoimmune diseases were greater in those with neoplasia. Two of the 14 patients with non-neoplastic BM and 1 with the neoplastic BM had nonhematological malignancy.Clinical and laboratory findings, the number of transplants, and the use of immunosuppressive agents can guide physicians to identify patients with a higher risk of developing hematologic malignancy. BM findings of cytopenia in SLE are often due to increased disease activity causing global cell death and dysmaturation. SLE patients presenting with cytopenias, with a history of long-term exposure to immunosuppressive drugs, should be regularly screened for hematologic and nonhematologic malignancies.


Assuntos
Neoplasias Hematológicas/epidemiologia , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , Leucopenia/diagnóstico , Lúpus Eritematoso Sistêmico/complicações , Trombocitopenia/diagnóstico , Adulto , Idoso , Biópsia/estatística & dados numéricos , Medula Óssea/patologia , Exame de Medula Óssea/estatística & dados numéricos , Suscetibilidade a Doenças , Feminino , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/patologia , Humanos , Transplante de Rim/estatística & dados numéricos , Leucopenia/sangue , Leucopenia/imunologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Trombocitopenia/sangue , Trombocitopenia/imunologia , Adulto Jovem
4.
Turk J Haematol ; 38(2): 145-150, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33375216

RESUMO

This study investigated the frequency of and predictive factors for autoimmune lymphoproliferative syndrome (ALPS) in children with lymphoma, chronic immune cytopenia, and nonmalignant organomegaly. Thirty-four children with suspected ALPS (n=13, lymphoma; n=12, immune cytopenia; n=9, nonmalignant organomegaly) were included. Double-negative T-cells, lymphocyte apoptosis, and genetic findings were analyzed. Patients were stratified into two groups as proven/probable ALPS and clinically suspected patients according to the ALPS diagnostic criteria. Of the 34 patients, 18 (53%) were diagnosed with proven/probable ALPS. One patient had a mutation (c.652-2A>C) in the FAS gene. The remaining 16 (47%) patients were defined as clinically suspected patients. Predictive factors for ALPS were anemia and thrombocytopenia in patients with lymphoma, splenomegaly and lymphadenopathy in patients with immune cytopenia, and young age in patients with nonmalignant organomegaly. ALPS may not be rare in certain risk groups. Our study indicates that screening for ALPS may be useful in children having lymphoma with cytopenia at diagnosis, in those having nonmalignant organomegaly with immune cytopenia, and in those having chronic immune thrombocytopenic purpura or autoimmune hemolytic anemia with organomegaly developing during follow-up.


Assuntos
Síndrome Linfoproliferativa Autoimune/diagnóstico , Leucopenia/diagnóstico , Linfoma/diagnóstico , Trombocitopenia/diagnóstico , Adolescente , Anemia/diagnóstico , Anemia/etiologia , Anemia/imunologia , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/etiologia , Anemia Hemolítica Autoimune/imunologia , Apoptose/imunologia , Síndrome Linfoproliferativa Autoimune/complicações , Síndrome Linfoproliferativa Autoimune/imunologia , Síndrome Linfoproliferativa Autoimune/patologia , Criança , Pré-Escolar , Doença Crônica , Estudos Transversais , Feminino , Humanos , Lactente , Leucopenia/etiologia , Leucopenia/imunologia , Linfadenopatia/diagnóstico , Linfadenopatia/etiologia , Linfadenopatia/imunologia , Linfoma/etiologia , Linfoma/imunologia , Masculino , Mutação , Valor Preditivo dos Testes , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/etiologia , Púrpura Trombocitopênica Idiopática/imunologia , Esplenomegalia/diagnóstico , Esplenomegalia/etiologia , Esplenomegalia/imunologia , Linfócitos T/imunologia , Linfócitos T/patologia , Trombocitopenia/etiologia , Trombocitopenia/imunologia , Receptor fas/genética
5.
Pediatr Transplant ; 25(5): e13909, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33141997

RESUMO

BACKGROUND: PGF is historically associated with high morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: In this study, we report our multicenter experience on stem cell boost (SCB) for PGF, or incomplete donor engraftment, in 16 pediatric patients. Donors were HLA-matched siblings (n = 4), unrelated donors (n = 11), or haploidentical family members (n = 1). Ten patients had two-lineage cytopenia, 5 had one-lineage cytopenia, and 1 had poor immunological reconstitution together with a low percentage of donor cell engraftment. A median of 6.6x106 selected CD34+/Kg was infused after 194 days from allo-HSCT (48-607). RESULTS: In 4 out of 5 patients, one-lineage cytopenia was resolved, while among the 10 patients with two-lineage cytopenia, 4 resolved both cytopenia, 5 resolved one-lineage, and one did not respond. All patients reverted their mixed chimera to full donor chimera. OS was 56%, transplant-related mortality (TRM) 32%, and RI 12%. The main causes of failure were related to infections with 4 out of 7 deaths caused by this. CONCLUSIONS: SCB may rescue over 50% of patients with PGF after allo-HSCT. An earlier treatment may reduce the infectious complications and improve survival.


Assuntos
Antígenos CD34/imunologia , Quimerismo , Transplante de Células-Tronco Hematopoéticas , Leucemia/imunologia , Leucemia/terapia , Leucopenia/imunologia , Leucopenia/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Itália , Masculino , Estudos Retrospectivos , Condicionamento Pré-Transplante
6.
Blood ; 136(23): 2667-2678, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-32659786

RESUMO

Glucocorticoids are considered first-line therapy in a variety of eosinophilic disorders. They lead to a transient, profound decrease in circulating human eosinophils within hours of administration. The phenomenon of glucocorticoid-induced eosinopenia has been the basis for the use of glucocorticoids in eosinophilic disorders, and it has intrigued clinicians for 7 decades, yet its mechanism remains unexplained. To investigate, we first studied the response of circulating eosinophils to in vivo glucocorticoid administration in 3 species and found that the response in rhesus macaques, but not in mice, closely resembled that in humans. We then developed an isolation technique to purify rhesus macaque eosinophils from peripheral blood and performed live tracking of zirconium-89-oxine-labeled eosinophils by serial positron emission tomography/computed tomography imaging, before and after administration of glucocorticoids. Glucocorticoids induced rapid bone marrow homing of eosinophils. The kinetics of glucocorticoid-induced eosinopenia and bone marrow migration were consistent with those of the induction of the glucocorticoid-responsive chemokine receptor CXCR4, and selective blockade of CXCR4 reduced or eliminated the early glucocorticoid-induced reduction in blood eosinophils. Our results indicate that glucocorticoid-induced eosinopenia results from CXCR4-dependent migration of eosinophils to the bone marrow. These findings provide insight into the mechanism of action of glucocorticoids in eosinophilic disorders, with implications for the study of glucocorticoid resistance and the development of more targeted therapies. The human study was registered at ClinicalTrials.gov as #NCT02798523.


Assuntos
Medula Óssea/imunologia , Eosinófilos/imunologia , Glucocorticoides/efeitos adversos , Leucopenia/induzido quimicamente , Leucopenia/imunologia , Receptores CXCR4/imunologia , Animais , Medula Óssea/patologia , Eosinófilos/patologia , Feminino , Glucocorticoides/administração & dosagem , Humanos , Leucopenia/patologia , Macaca mulatta , Masculino , Camundongos
7.
Rheumatology (Oxford) ; 59(11): 3468-3478, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32375176

RESUMO

OBJECTIVES: In SLE, heterogeneous clinical expression and activity may reflect diverse pathogenic and/or effector mechanisms. We investigated SLE heterogeneity by assessing the expression of three gene sets representative of type I IFN (IFN-I), polymorphonuclear neutrophil (PMN) and plasmablast (PB) signatures in a well-characterized, multidisciplinary cohort of SLE patients. We further assessed whether individual gene products could be representative of these three signatures. METHODS: Whole blood, serum and clinical data were obtained from 140 SLE individuals. Gene expression was assessed by NanoString technology, using a panel of 37 probes to compute six IFN-I, one PMN and one PB scores. Protein levels were measured by ELISA. RESULTS: Depending on the score, 45-50% of SLE individuals showed high IFN-I gene expression. All six IFN-I scores were significantly associated with active skin involvement, and two of six were associated with arthritis. IFN-induced Mx1 protein (MX1) level was correlated with IFN-I score (P < 0.0001) and associated with a similar clinical phenotype. In all, 25% of SLE individuals showed high PMN gene expression, associated with SLE fever, serositis, leukopoenia and glucocorticoid use. PB gene expression was highly affected by immunosuppressant agents, with no association with SLE features. Combined IFN-I and PMN gene scores were significantly associated with high disease activity and outperformed anti-dsDNA and anti-C1q autoantibody and complement levels for predicting SLE activity. CONCLUSION: IFN-I and PMN gene scores segregate with distinct SLE clinical features, and their combination may identify high disease activity. MX1 protein level performed similar to IFN-I gene expression.


Assuntos
Autoanticorpos/imunologia , Interferon Tipo I/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Neutrófilos/imunologia , Transcriptoma , Adulto , Idoso , Anticorpos Antinucleares/imunologia , Anticorpos Antifosfolipídeos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Complemento C3/imunologia , Complemento C4/imunologia , Feminino , Febre/imunologia , Febre/fisiopatologia , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Interferon Tipo I/genética , Leucopenia/imunologia , Leucopenia/fisiopatologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/metabolismo , Neutrófilos/metabolismo , Serosite/imunologia , Serosite/fisiopatologia , Índice de Gravidade de Doença , Adulto Jovem , Proteínas Centrais de snRNP/imunologia
8.
Oncol Res Treat ; 41(9): 539-543, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30114706

RESUMO

AIMS: The acute respiratory distress syndrome (ARDS) is a frequent condition following pneumonia in immunocompromised cancer patients. Extracorporeal membrane oxygenation (ECMO) may serve as a rescue therapy in refractory ARDS but has still not been studied in predominantly leuco- and thrombocytopenic cancer patients. PATIENTS AND METHODS: In this monocentric, retrospective, observational study, we assessed all cancer patients treated with ECMO for ARDS between 2013 and 2017. RESULTS: 25 patients, 11 of whom underwent haematopoietic stem cell transplantation (SCT), were analysed. The main reason for ARDS was pneumonia in 72%. All patients were under invasive ventilation at ECMO. All but 9/3 patients suffered from leuco-/thrombocytopenia due to anti-cancer treatment or underlying disease. Overall, 17 patients (68%) died on ECMO, whereas 5 patients survived to hospital discharge (20%). All patients after recent allogeneic (allo-)SCT have died. 4 patients experienced severe bleeding events. CONCLUSIONS: Discouraging survival rates in patients treated after allo-SCT do not support the use of ECMO for ARDS in this patient subgroup. On the contrary, cancer patients in at least stable disease otherwise eligible for full-code intensive care unit management, even those with severe thrombocytopenia, may be potential candidates for ECMO in case of severe ARDS failing conventional measures.


Assuntos
Oxigenação por Membrana Extracorpórea , Neoplasias Hematológicas/terapia , Leucopenia/terapia , Síndrome do Desconforto Respiratório/terapia , Trombocitopenia/terapia , Adulto , Feminino , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Transplante de Células-Tronco Hematopoéticas , Humanos , Hospedeiro Imunocomprometido , Leucopenia/imunologia , Masculino , Pessoa de Meia-Idade , Pneumonia/sangue , Pneumonia/imunologia , Pneumonia/mortalidade , Pneumonia/terapia , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Trombocitopenia/imunologia , Resultado do Tratamento
9.
J Stroke Cerebrovasc Dis ; 27(3): 555-562, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29097060

RESUMO

BACKGROUND: There are notable changes in the number of white blood cells (WBCs) after stroke, but the primary mediators of these changes are unclear. In this study, we assessed the role of the neuroendocrine and sympathetic nervous systems in stroke-induced changes of WBCs within distinct leukocyte subsets, as well as the effect of these changes on stroke outcomes. METHODS: Patients were recruited within 72 hours after ischemic stroke; complete blood count with differential was obtained at set time points. The relationships among leukocyte numbers, cortisol, adrenocorticotropic hormone, interleukin-6, and metanephrines were assessed at 72 hours after stroke. Associations between abnormal leukocyte counts at 72 hours, poststroke infection, and 3-month outcomes were determined. RESULTS: A total of 114 subjects were enrolled. Severe stroke was associated with leukocytosis, neutrophilia, monocytosis, lymphopenia, and eosinopenia. At 72 hours after stroke, increased serum cortisol was independently associated with neutrophilia and lymphopenia. Abnormal leukocyte counts were not independently predictive of poststroke infection, but lymphopenia was associated with poor outcome (modified Rankin score >3) at 3 months after stroke (odds ratio = 22.86 [1.95, 267.65]; P = .01). CONCLUSIONS: Increased serum cortisol is independently associated with neutrophilia and lymphopenia after stroke. Lymphopenia is not an independent predictor of infections but is independently associated with worse outcome.


Assuntos
Hidrocortisona/sangue , Leucócitos/imunologia , Leucopenia/sangue , Metanefrina/sangue , Acidente Vascular Cerebral/sangue , Hormônio Adrenocorticotrópico/sangue , Biomarcadores/sangue , Doenças Transmissíveis/sangue , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/imunologia , Avaliação da Deficiência , Humanos , Interleucina-6/sangue , Contagem de Leucócitos , Leucopenia/diagnóstico , Leucopenia/imunologia , Linfopenia/sangue , Linfopenia/diagnóstico , Linfopenia/imunologia , Imageamento por Ressonância Magnética , Prognóstico , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/imunologia , Fatores de Tempo
10.
Mol Immunol ; 90: 136-142, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28750255

RESUMO

Patients with primary Sjögren's syndrome, a systemic autoimmune disease, have been shown to have serum autoantibodies that react with the muscarinic acetylcholine type 3 receptor (M3R).Primary Sjögren's syndrome is a systemic autoimmune disease. Patients with primary Sjögren's syndrome have been shown to have serum autoantibodies that react with the muscarinic acetylcholine type 3 receptor (M3R). Leukopenia has been reported to be significantly more common in primary Sjögren's syndrome patients who have anti-M3R-autoantibodies in their sera. In this study, we investigated whether these anti-M3R autoantibodies have effects on M3R and MHCI expression in Jurkat T cells. Purified IgG antibodies were isolated from the serum of healthy individuals and primary Sjögren's syndrome patients. Jurkat cell line was used to represent T lymphocytes. In situ immunofluorescence confocal microscopy was used to confirm the binding reactivity of primary Sjögren's syndrome IgG antibodies to M3R. Co-immunoprecipitation and immunofluorescence results suggested a direct interaction between M3R and MHC I. Co-internalization of M3R and MHC I was observed when Jurkat cells were exposed to the primary Sjögren's syndrome IgG, but this primary Sjögren's syndrome IgG-induced co-internalization of M3R and MHC I was prevented by the presence of exogenous IFN-γ. Primary Sjögren's syndrome IgG itself did not affect the viability of Jurkat cells, but Jurkat cells exposed to primary Sjögren's syndrome IgG were observed to undergo significant cell death when co-cultured with primary Natural Killer cells. Our results suggest that anti-M3R autoantibodies in primary Sjögren's syndrome induce downregulation of plasma membrane-resident M3R and MHC class I molecules in leukocytes followed by NK cell-mediated cell death. This mechanism may explain the frequency of leukopenia occurrence in patients with primary Sjögren's syndrome.


Assuntos
Autoanticorpos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Leucócitos/imunologia , Receptor Muscarínico M3/imunologia , Síndrome de Sjogren/imunologia , Adulto , Idoso , Morte Celular/imunologia , Linhagem Celular Tumoral , Feminino , Imunofluorescência , Humanos , Imunoglobulina G/imunologia , Imunoprecipitação , Células Jurkat , Leucopenia/imunologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade
11.
Cerebrovasc Dis ; 43(3-4): 99-109, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28049200

RESUMO

BACKGROUND: Stroke-induced immunodeficiency increases the risk of infectious complications, which adversely affects neurological outcome. Among those, pneumonia affects as many as one third of stroke patients and is the main contributor to mortality in the post-acute phase of stroke. Experimental findings on post-stroke susceptibility to spontaneous pneumonia in mice are contradictory. Here, we established a mouse model inducing standardized bacterial pneumonia and characterized the impaired pulmonary cellular and humoral immune responses after experimental stroke. METHODS: Bacterial pneumonia was induced by intra-tracheal inoculation with Streptococcus pneumoniae at different time points after transient middle cerebral artery occlusion (MCAO). Bacterial counts in lungs and blood, histological changes, and cytokine production in the lungs were assessed. Furthermore, we investigated the effect of pneumonia on stroke outcome. RESULTS: Intra-tracheal inoculation resulted in reproducible pneumonia and bacteraemia, and demonstrated post-stroke susceptibility to streptococcal pneumonia developing with a delay of at least 24 h after MCAO. Higher bacterial counts in mice infected 3 days after stroke induction correlated with reduced neutrophil and macrophage infiltration in the lungs and lower levels of pro-inflammatory cytokines in the broncho-alveolar lavage compared to sham-operated animals. Pneumonia increased mortality without affecting brain-infiltrating leukocytes. CONCLUSIONS: In this standardized mouse model of post-stroke pneumonia, we describe attenuated leukocyte infiltration and cytokine production in response to bacterial infection in the lungs that has a profound effect on outcome.


Assuntos
Hospedeiro Imunocomprometido , Infarto da Artéria Cerebral Média/imunologia , Pulmão/microbiologia , Infecções Oportunistas/microbiologia , Pneumonia Pneumocócica/microbiologia , Streptococcus pneumoniae/patogenicidade , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno , Exposição por Inalação , Leucopenia/sangue , Leucopenia/imunologia , Leucopenia/microbiologia , Pulmão/imunologia , Pulmão/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Infecções Oportunistas/sangue , Infecções Oportunistas/imunologia , Pneumonia Pneumocócica/sangue , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/imunologia , Fatores de Tempo
12.
Surg Obes Relat Dis ; 12(7): 1418-1423, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27260650

RESUMO

BACKGROUND: Obesity is associated with higher leukocyte counts, whereas weight loss decreases these counts. It is unknown if different bariatric surgery (BS) types have different effects on leukocytes. OBJECTIVES: The aim of the study was to determine predictors of leukocyte and their subset count variation in patients submitted to BS. SETTING: Tertiary care university hospital, Porto, Portugal. METHODS: This was a retrospective analysis of patients submitted to Roux-en-Y gastric bypass (RYGB), laparoscopic adjustable gastric banding (LAGB), or sleeve gastrectomy (SG). Leukocyte and subset counts were compared between baseline and 1-year postsurgery and between BS types. A multivariate linear regression model was built to study determinants of leukocyte and subset variation. RESULTS: We analyzed 764 patients: 238 submitted to LAGB; 452 to RYGB, and 74 to SG. Mean age was 42 years and 86.6% were women. All BS types were associated with a decrease in leukocyte and neutrophil counts but the variation in body mass index and homeostatic model assessment (HOMA-IR) were the only variables independently associated with a decrease 1-year postsurgery. Monocytes increased in patients submitted to LAGB and decreased in those who underwent RYGB and SG. The BS type was independently associated with monocyte variation. Patients who underwent RYGB and SG had a decrease in monocyte counts of 77/µL and 62/µL, respectively, compared with LAGB. CONCLUSION: Weight and insulin resistance are the main predictors of leukocyte and neutrophil variation after BS. The specific type of BS is a determinant of monocyte count variation independent of the amount of weight loss or the degree of insulin resistance improvement.


Assuntos
Cirurgia Bariátrica/métodos , Leucócitos Mononucleares/fisiologia , Neutrófilos/fisiologia , Obesidade/cirurgia , Adolescente , Adulto , Idoso , Análise de Variância , Cirurgia Bariátrica/efeitos adversos , Índice de Massa Corporal , Peso Corporal/fisiologia , Feminino , Humanos , Resistência à Insulina/imunologia , Resistência à Insulina/fisiologia , Contagem de Leucócitos , Leucopenia/etiologia , Leucopenia/imunologia , Masculino , Pessoa de Meia-Idade , Neutropenia/etiologia , Neutropenia/imunologia , Obesidade/imunologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Adulto Jovem
13.
Georgian Med News ; (252): 84-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27119841

RESUMO

From the positive effects of the drugs prepared from various parts of walnut described for a wide variety of diseases, their antitumor effect is remarkable. This feature can be used for treatment of leukopenia caused by radiotherapy and/or chemotherapy. Therefore, to study the immunocorrective properties of Greek walnut, the walnut septa were selected, aqueous extract of which has been studied on experimental model of leukopenia in white mice caused by a single injection of cyclophosphamide. The material of the study were the blood and bone marrow smears from intact and tested adult mice stained by Giemsa's dye. The quantity of leukocytes in peripheral blood were determined by the counting chamber under the light microscope with standard protocol. Cloud-point extraction, HPLC analysis and UV-visible spectrophotometry were used to study the composition of the walnut septa extract. It has been established that the Greek walnut septa extract has the correction ability of suppressed myelopoiesis in white mice caused by injection of cyclophosphamide. The blood formula normalization process by the mentioned extract is provided by the fast increasing in number of immature (band neutrophil) and mature neutrophils in the peripheral blood. It was shown that walnut septa extract stimulates the division, differentiation and maturation of blast forms of myeloid as well as lymphoid line in the bone marrow of mice with leukopenia. Cloud-point extraction and liquid-chromatographic analysis revealed the presence of hydrophilic and hydrophobic components in the walnuts septum extract.


Assuntos
Fatores Imunológicos/uso terapêutico , Juglans/química , Leucopenia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Alquilantes/toxicidade , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ciclofosfamida/toxicidade , Fatores Imunológicos/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/patologia , Leucopenia/induzido quimicamente , Leucopenia/imunologia , Camundongos , Extratos Vegetais/farmacologia
14.
Bull Exp Biol Med ; 160(4): 474-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26906195

RESUMO

The model of streptozotocin-induced diabetes mellitus in C57Bl/6 mice was employed to study the role of precursors of insulin-producing ß-cells, hematopoietic stem cells, and progenitor hematopoietic cells in inflammation. In addition to provoking hyperglycemia, streptozotocin elevated serum levels of IL-1ß and hyaluronic acid, induced edema in the pancreatic insular tissue and its infiltration by inflammatory cells (neutrophils, lymphocytes, and macrophages) and fibroblasts. Inflammation in pancreatic islets was accompanied by necrotic processes and decreasing counts of multipotent progenitor ß-cells (CD45(-), TER119(-), c-kit-1(-), and Flk-1(-)), oligopotent progenitor ß-cells (CD45(-), TER119(-), CD133(+), and CD49f(low)), and insulinproducing ß-cells (Pdx1(+)). Pancreatic infl ammation was preceded by elevation of the number of short-term hematopoietic stem cells (Lin-Sca-1(+)c-kit(+)CD34(+)) relative to long-term cells (Lin(-)Sca-1(+)c-kit(+)CD34(-)) in the bone marrow as well as recruitment of hematopoietic stem and progenitor cells into circulation. Transplantation of bone marrow hematopoietic stem and progenitor cells from diabetic C57Bl/6 donor mice to recipient CBA mice with 5-fluorouracilinduced leukopenia accelerated regeneration of granulocytopoiesis in recipient mice.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Diabetes Mellitus Experimental/terapia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Hiperglicemia/terapia , Células Secretoras de Insulina/citologia , Leucopenia/terapia , Animais , Células da Medula Óssea , Diferenciação Celular , Diabetes Mellitus Experimental/patologia , Fluoruracila , Granulócitos/citologia , Ácido Hialurônico/sangue , Hiperglicemia/induzido quimicamente , Inflamação/terapia , Células Secretoras de Insulina/patologia , Interleucina-1beta/sangue , Leucopenia/induzido quimicamente , Leucopenia/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Estreptozocina
15.
Eur J Cancer ; 54: 49-56, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26720403

RESUMO

Mandatory for the diagnosis of myelodysplastic syndromes (MDS) is the presence of dysplasia in >10% of cells within one or more cell lineages or presence of >15% ring sideroblasts or presence of MDS-associated cytogenetic (CG) abnormalities. Discrimination between neo-plastic and non-neoplastic causes of cytopenias can be challenging when dysplastic features by cytomorphology (CM) are minimal and CG abnormalities are absent or non-discriminating from other myeloid neoplastic disorders. This study evaluated a standard diagnostic approach in 379 patients with unexplained cytopenias and highlights the additional value of flow cytometry (FC) in patients with indeterminate CM and CG. CM reached no clear-cut diagnosis in 44% of the patients. Here, CG was able to identify two additional patients with MDS; other CG results did not reveal abnormalities or were not contributory. Based on the FC results, patients without a diagnosis by CM and CG were categorized 'no MDS-related features' (65%), 'limited number of MDS-related changes' (24%), and 'consistent with MDS' (11%). Patients were followed over time in an attempt to establish or confirm a diagnosis (median follow-up 391 d, range 20-1764). The specificity (true negative) of MDS-FC analysis calculated after follow-up was 95%. FC can aid as a valuable tool to exclude MDS when CM and additional CG are not conclusive in patients with cytopenia.


Assuntos
Citometria de Fluxo/métodos , Imunofenotipagem/métodos , Leucopenia/diagnóstico , Síndromes Mielodisplásicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/análise , Biomarcadores/análise , Exame de Medula Óssea , Diagnóstico Diferencial , Feminino , Humanos , Antígenos Comuns de Leucócito/análise , Leucopenia/etiologia , Leucopenia/genética , Leucopenia/imunologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/imunologia , Células Progenitoras Mieloides/imunologia , Fenótipo , Células Precursoras de Linfócitos B/imunologia , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Fatores de Tempo , Adulto Jovem
16.
BMC Cancer ; 15: 573, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26242181

RESUMO

BACKGROUND: Tumor-associated macrophages (TAMs) are implicated in the growth, invasion and metastasis of various solid tumors. However, the phenotype of TAMs in premalignant lesions of solid tumors has not been clarified. In the present study, we identify the phenotype of TAMs in leukoplakia, an oral premalignant lesion, by immunohistochemical analysis and investigate the involvement of infiltrated T cells that participate in the polarization of TAMs. METHODS: The subjects included 30 patients with oral leukoplakia and 10 individuals with normal mucosa. Hematoxylin and eosin slides were examined for the histological grades, and immunohistochemical analysis was carried out using antibodies against CD68 (pan-MΦ), CD80 (M1 MΦ), CD163 (M2 MΦ), CD4 (helper T cells: Th), CD8 (cytotoxic T cells), CXCR3, CCR5 (Th1), CCR4 (Th2), signal transducer and activator of transcription (STAT1), phosphorylated STAT1 (pSTAT1) and chemokine CXCL9. The differences in the numbers of positively stained cells among the different histological grades were tested for statistical significance using the Kruskal-Wallis test. Correlations between different types of immune cells were determined using Spearman's rank analysis. RESULTS: An increase in the rate of CD163(+) TAM infiltration was observed in mild and moderate epithelial dysplasia, which positively correlated with the rate of intraepithelial CD4(+) Th cell infiltration. Although CCR4(+) cells rarely infiltrated, CXCR3(+) and CCR5(+) cells were observed in these lesions. Cells positive for STAT1 and chemokine CXCL9, interferon- (IFN)-induced gene products, and pSTAT1 were also observed in the same lesions. Double immunofluorescence staining demonstrated that the cells that were positive for CD163 were also positive for STAT1. CONCLUSIONS: CD163(+) TAMs in oral premalignant lesions coexpress CD163 and STAT1, suggesting that the TAMs in oral premalignant lesions possess an M1 phenotype in a Th1-dominated micromilieu.


Assuntos
Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Macrófagos/metabolismo , Macrófagos/patologia , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Lesões Pré-Cancerosas , Receptores de Superfície Celular/genética , Fator de Transcrição STAT1/genética , Células Th1/metabolismo , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Biomarcadores , Biópsia , Estudos de Casos e Controles , Feminino , Humanos , Leucopenia/genética , Leucopenia/imunologia , Leucopenia/patologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/imunologia , Gradação de Tumores , Ligação Proteica , Transporte Proteico , Receptores CXCR3/metabolismo , Receptores de Superfície Celular/metabolismo , Fator de Transcrição STAT1/metabolismo , Células Th1/imunologia , Microambiente Tumoral
17.
Diagn Pathol ; 10: 44, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25924846

RESUMO

BACKGROUND: Immunophenotyping is a valuable ancillary technique for the differential diagnosis between myelodysplastic syndromes (MDS) with low bone marrow (BM) blast counts and a normal karyotype, and reactive peripheral (PB) cytopenias. Our aim was to search for the most important variables for this purpose. We also analyzed the age variation of BM B-cell precursors (BCP) and its differences in reactive and clonal cytopenias. METHODS: Immunophenotypic analyzes were performed in BM of 54 patients with MDS (76% with BM blasts <5%) and 35 cases of reactive cytopenias. Healthy allogeneic BM transplantation donors (n = 41) were used as controls. We used a four-color panel of antibodies analyzing 9 granulocytic, 8 monocytic and 6 CD34(+) cell features. RESULTS: Asynchronous shift to the left in maturing granulocytes and increase in CD16(+) monocytes were also found in reactive PB cytopenias, but the most important aberrancies in MDS were seen in myeloid CD34(+) cells. Decrease in BCP, that is a hallmark of MDS, could also be found in reactive cytopenias, especially in patients >55 years. % BM BCP could be calculated by the formula: (-7.97 × log age) + (4.24 × log % CD34 (+) cells) - (0.22 x nr. alterations CD34 (+) cells) + 0.577. Corrected R(2) = 0.467. CONCLUSION: Analysis of myelomonocytic precursors and CD34(+) cells was satisfactory for the differential diagnosis between reactive PB cytopenias and MDS. The most specific alterations were found in CD34(+) cells. Comparison of the values obtained with those of normal age-matched controls is recommended. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1975931809154663.


Assuntos
Citometria de Fluxo , Imunofenotipagem/métodos , Leucopenia/diagnóstico , Síndromes Mielodisplásicas/diagnóstico , Células Precursoras de Linfócitos B/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/análise , Biomarcadores/análise , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Humanos , Cariotipagem , Leucopenia/genética , Leucopenia/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/imunologia , Valor Preditivo dos Testes , Adulto Jovem
18.
Lupus ; 24(11): 1221-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25914407

RESUMO

Autologous hematopoietic stem cell (HSC) and mesenchymal stem cell (MSC) transplantation is currently being evaluated as a novel treatment for autoimmune diseases, such as systemic lupus erythematosus (SLE). Here we report a case of autologous HSC transplantation combined with MSCs in a 25-year-old severe SLE patient with multiple life-threatening complications and refractory to conventional cyclophosphamide (CYC) therapy. After being pretreated with CYC, fludarabine and antithymocyte globulin, the patient was transplanted with autologous CD34+HSCs and MSCs by intravenous infusion. Hematopoietic regeneration was observed on day 12 thereafter. After HSC and MSC transplantation, the patient's clinical symptoms caused by SLE were remitted, and the SLEDAI score decreased. Moreover, CD4+CD25+FoxP3+Treg cells increased in peripheral blood mononuclear cells (PBMCs) after transplantation. This result suggests that the combined transplantation of HSCs and MSCs may reset the adaptive immune system to re-establish self-tolerance in SLE. A 36-month follow-up showed that the clinical symptoms remained in remission. Although a longer follow-up is required for assessing the long-term efficacy, our present results suggest that the combined transplantation of HSCs and MSCs may be a novel and effective therapy for refractory SLE.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/terapia , Nefrite Lúpica/imunologia , Nefrite Lúpica/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Linfócitos T Reguladores/imunologia , Adulto , Terapia Combinada , Ciclofosfamida/uso terapêutico , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Leucopenia/imunologia , Leucopenia/patologia , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Linfócitos T Reguladores/patologia , Transplante Autólogo
19.
BMC Pulm Med ; 15: 8, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25879889

RESUMO

BACKGROUND: GATA-2 transcription factor deficiency has recently been described in patients with a propensity towards myeloid malignancy associated with other highly variable phenotypic features: chronic leukocytopenias (dendritic cell-, monocyto-, granulocyto-, lymphocytopenia), increased susceptibility to infections, lymphatic vasculature abnormalities, and sensorineural deafness. Patients often suffer from opportunistic respiratory infections; chronic pulmonary changes have been found in advanced disease. CASE PRESENTATION: We present a case of a 17-year-old previously healthy Caucasian male who was admitted to the hospital with fever, malaise, headache, cough and dyspnea. A chest X-ray revealed bilateral interstitial infiltrates and pneumonia was diagnosed. Despite prompt clinical improvement under antibiotic therapy, interstitial changes remained stable. A high resolution computer tomography showed severe diffuse parenchymal lung disease, while the patient's pulmonary function tests were normal and he was asymptomatic. Lung tissue biopsy revealed chronic reparative and resorptive reaction with organizing vasculitis. At the time of the initial presentation to the hospital, serological signs of acute infection with Epstein-Barr virus (EBV) were present; EBV viremia with atypical serological response persisted during two-year follow up. No other infectious agents were found. Marked monocytopenia combined with B-cell lymphopenia led to a suspicion of GATA-2 deficiency. Diagnosis was confirmed by detection of the previously published heterozygous mutation in GATA2 (c.1081 C > T, p.R361C). The patient's brother and father were both carriers of the same genetic defect. The brother had no clinically relevant ailments despite leukocyte changes similar to the index patient. The father suffered from spondylarthritis, and apart from B-cell lymphopenia, no other changes within the leukocyte pool were seen. CONCLUSION: We conclude that a diagnosis of GATA-2 deficiency should be considered in all patients with diffuse parenchymal lung disease presenting together with leukocytopenia, namely monocyto-, dendritic cell- and B-lymphopenia, irrespective of severity of the clinical phenotype. Genetic counseling and screening for GATA2 mutations within the patient's family should be provided as the phenotype is highly variable and carriers without apparent immunodeficiency are still in danger of developing myeloid malignancy. A prompt recognition of this rare condition helps to direct clinical treatment strategies and follow-up procedures.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Fator de Transcrição GATA2/deficiência , Doenças Pulmonares Intersticiais/genética , Pulmão/patologia , Linfopenia/genética , Adolescente , Linfócitos B/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/imunologia , Humanos , Leucopenia/genética , Leucopenia/imunologia , Pulmão/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/imunologia , Linfopenia/imunologia , Masculino , Monócitos/imunologia , Mutação , Radiografia , Síndrome , Vasculite/diagnóstico , Vasculite/genética , Vasculite/imunologia
20.
PLoS One ; 9(10): e110011, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25330314

RESUMO

Incidences of leukopenia caused by bacteremia have increased significantly and it is associated with prolonged hospital stay and increased cost. Immunoproteomic is a promising method to identify pathogenicity factors of different diseases. In the present study, we used immunoproteomic to analysis the pathogenicity factors in leukopenia caused by Klebsiella Pneumonia bacteremia. Approximately 40 protein spots localized in the 4 to 7 pI range were detected on two-dimensional electrophoresis gels, and 6 differentially expressed protein spots between 10 and 170 kDa were identified. Pathogenicity factors including S-adenosylmethionine synthetase, pyruvate dehydrogenase, glutathione synthetase, UDP-galactose-4-epimerase, acetate kinase A and elongation factor tu (EF-Tu). In validation of the pathogenicity factor, we used western blotting to show that Klebsiella pneumonia had higher (EF-Tu) expression when they accompanied by leukopenia rather than leukocytosis. Thus, we report 6 pathogenicity factors of leukopenia caused by Klebsiella pneumonia bacteremia, including 5 housekeeping enzymes and EF-Tu. We suggest EF-Tu could be a potential pathogenicity factor for leukopenia caused by Klebsiella pneumonia.


Assuntos
Bacteriemia/complicações , Infecções por Klebsiella/complicações , Leucopenia/imunologia , Leucopenia/metabolismo , Pneumonia/complicações , Proteômica , Feminino , Humanos , Leucopenia/etiologia , Masculino , Pessoa de Meia-Idade
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