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1.
Clin Exp Dermatol ; 44(4): e89-e95, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30552699

RESUMO

BACKGROUND: Lichen planus (LP) is an inflammatory skin disease with unknown aetiology. Activation by pathogen-associated molecular patterns or environmental stimuli may activate some components of inflammasomes that contribute to the inflammatory process in LP lesions. AIM: To characterize the inflammasomes in skin lesions and peripheral blood mononuclear cells (PBMCs) of patients with LP under Toll-like receptor (TLR) activation. METHODS: In total, 15 patients with LP and 14 healthy controls (HCs) were enrolled in the study. Inflammasome expression in skin was evaluated by real-time PCR and immunohistochemistry, while ELISA was used to assess the production of interleukin (IL)-1ß by PBMCs under stimulation with TLR4 and TLR7/TLR8 agonists and adenosine triphosphate (ATP). RESULTS: Compared with the levels in HC samples, increased expression of the inflammasome AIM2 was verified in both epidermal and dermal sections of LP skin lesions, whereas NLRP1 and IL-ß expression levels were enhanced in the dermis. LP skin lesion samples exhibited higher AIM2 transcript levels, similar NLRP1 levels and lower pro-IL-1ß mRNA levels compared with HC samples. We verified that, compared with PBMCs from HC subjects, PBMCs from patients with LP produced similar amounts of IL-1ß after induction by TLR4 agonists but lower IL-1ß levels after induction by TLR7/TLR8 agonists, regardless of the addition of ATP. CONCLUSION: Alterations in innate immunity, such as inflammasome component expression in skin lesions and PBMCs, were observed in patients with LP. Further investigations of dysfunctional inflammasome activation and the chronic inflammatory status of LP are required.


Assuntos
Inflamassomos/genética , Leucócitos Mononucleares/metabolismo , Líquen Plano/metabolismo , Dermatopatias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Proteínas Reguladoras de Apoptose , Proteínas de Ligação a DNA , Feminino , Humanos , Imunidade Inata/imunologia , Interleucina-1beta/metabolismo , Líquen Plano/patologia , Masculino , Pessoa de Meia-Idade , Proteínas NLR , RNA Mensageiro/genética , Dermatopatias/patologia , Receptor 7 Toll-Like , Receptor 8 Toll-Like , Receptores Toll-Like , Regulação para Cima/genética
2.
J Hosp Infect ; 97(3): 241-246, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28826688

RESUMO

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) have been reported worldwide and are associated with high mortality rates. Intestinal colonization acts as a reservoir and fosters exchange of resistance mechanisms. AIM: To investigate the prevalence of patients harbouring CRE on hospital admission, risk factors associated, and the acquisition rate within the emergency department (ED). METHODS: This was a cross-sectional survey with 676 patients consecutively admitted to the ED study during the months of May to July 2016. A questionnaire was performed and rectal swabs were collected from patients on admission, for culture and for multiplex real-time polymerase chain reaction (PCR). If the patient was hospitalized for more than one week in the ED, samples were taken again to determine the acquisition rate of CRE. FINDINGS: Forty-six patients were colonized; all positive PCR were Klebsiella pneumoniae carbapenemase. The acquisition rate was 18%. Previous exposure to healthcare in the last year, liver disease, and use of antibiotics in the last month were risk factors for colonization. Six patients with no previous exposure to healthcare were CRE-colonized on admission, suggesting transmission of CRE within the community. CONCLUSION: Screening of high-risk patients on admission to the ED is a strategy to early identify CRE carriage and may contribute to control CRE dissemination.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Serviço Hospitalar de Emergência , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Prevalência , Reto/microbiologia , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
3.
Mycoses ; 56(3): 281-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23145831

RESUMO

Dermatophytes invade the stratum corneum of the skin and other keratinized tissues such as hair and nails, and Trichophyton rubrum causes approximately 80% of cutaneous mycoses in humans. To evaluate the cellular immune response of patients with extensive dermatophytosis caused by T. rubrum, we evaluated lymphocyte populations, the lymphoproliferative response to: phytohaemagglutinin (PHA); anti-CD3 (OKT3); and pokeweed mitogen (PWM), Candida sp. (CMA), an extract of T. rubrum, and the main fungal epitope TriR2 (T). We also evaluated interleukin (IL)-4, IL-10, IL-12 and IFN-γ after stimulation by PHA, CMA and TriR2. The immunophenotyping showed no differences between patients and controls. The lymphoproliferation test showed significant differences between the groups stimulated by PWM and CMA, as well as against TriR2, being significantly higher for the control group. Conversely, there were similar results for the groups after stimulation by the extract. The cytokines' quantification showed a significant difference between the groups only for IFN-γ stimulated by PHA and TriR2. We can conclude that the fungal extract can stimulate lymphoproliferation by both groups' lymphocytes. However, the response to Tri r2 was more specific. We showed that some patients with extensive dermatophytosis have normal cellular response, recognising both the extract and TriR2.


Assuntos
Imunidade Celular , Tinha/imunologia , Trichophyton/imunologia , Antígenos de Fungos/imunologia , Candida/imunologia , Estudos de Casos e Controles , Proliferação de Células , Epitopos/imunologia , Seguimentos , Humanos , Imunofenotipagem , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-4/imunologia , Ativação Linfocitária , Contagem de Linfócitos , Muromonab-CD3/imunologia , Fito-Hemaglutininas/imunologia , Mitógenos de Phytolacca americana/imunologia , Tinha/microbiologia
4.
Clin Exp Immunol ; 168(1): 60-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22385239

RESUMO

Several studies correlated genetic background and pancreatic islet-cell autoantibody status (type and number) in type 1A diabetes mellitus (T1AD), but there are no data evaluating the relationship among these markers with serum cytokines, regulatory T cells and ß cell function. This characterization has a potential importance with regard to T1AD patients' stratification and follow-up in therapeutic prevention. In this study we showed that peripheral sera cytokines [interleukin (IL)-12, IL-6, II-1ß, tumour necrosis factor (TNF)-α, IL-10] and chemokines (CXCL10, CXCL8, CXCL9, CCL2) measured were significantly higher in newly diagnosed T1AD patients when compared to healthy controls (P < 0·001). Among T1AD, we found a positive correlation between CXCL10 and CCL-2 (r = 0·80; P = 0·000), IL-8 and TNF-α (r = 0·60; P = 0·000); IL-8 and IL-12 (r = 0·57; P = 0·001) and TNF-α and IL-12 (r = 0·93; P = 0·000). Glutamic acid decarboxylase-65 (GAD-65) autoantibodies (GADA) were associated negatively with CXCL10 (r = -0·45; P = 0·011) and CCL2 (r = -0·65; P = 0·000), while IA-2A showed a negative correlation with IL-10 (r = -0·38; P = 0·027). Human leucocyte antigen (HLA) DR3, DR4 or DR3/DR4 and PTPN22 polymorphism did not show any association with pancreatic islet cell antibodies or cytokines studied. In summary, our results revealed that T1AD have a proinflammatory cytokine profile compared to healthy controls and that IA-2A sera titres seem to be associated with a more inflammatory peripheral cytokine/chemokine profile than GADA. A confirmation of these data in the pre-T1AD phase could help to explain the mechanistic of the well-known role of IA-2A as a more specific marker of beta-cell damage than GADA during the natural history of T1AD.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Adolescente , Autoanticorpos/imunologia , Quimiocinas/sangue , Criança , Citocinas/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Feminino , Predisposição Genética para Doença , Genótipo , Glutamato Descarboxilase/genética , Antígeno HLA-DR3/genética , Antígeno HLA-DR4/genética , Humanos , Células Secretoras de Insulina/imunologia , Masculino , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética
5.
J Eur Acad Dermatol Venereol ; 26(3): 319-24, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21623925

RESUMO

BACKGROUND: Infliximab and etarnecept are now widely used for treating severe psoriasis. However, these drugs, especially infliximab, increased the risk of tuberculosis reactivation. Surprisingly, epidemiological data suggest that the tuberculosis rate in patients taking infliximab in São Paulo State, Brazil, is similar to that of some developed, non-endemic countries. OBJECTIVE: The aim of this study was to better understand the effect of infliximab on Mycobacterium tuberculosis (Mtb) immune responses of psoriasis patients in an endemic setting (Brazil). METHODS: We evaluated the tuberculosis-specific immune responses of severe psoriasis patients and healthy individuals, both tuberculin skin test (TST) positive, in the presence/absence of infliximab. Patients had untreated severe psoriasis, no co-morbidities affecting the immune responses and a TST >10 mm. Healthy TST(+) (>10 mm) individuals were evaluated in parallel. PBMC cultures from both groups were stimulated with different Mycobacterium tuberculosis (Mtb) antigens (ESAT-6, 85B and Mtb lysate) and phytohemagglutinin, with or without infliximab (5 µg/mL). Parameters evaluated were TNF-α, IFN-γ and IL-10 secretion by ELISA, overnight IFN-γ ELISpot and lymphocyte proliferative response (LPR). RESULTS: Infliximab almost abolished TNF-α detection in PBMC supernatants of both groups. It also significantly reduced the LPR to phytohemagglutinin and the Mtb antigens as well as the IFN-γ levels secreted into day 5 supernatants in both groups. There was no concomitant exaggerated IL-10 secretion that could account for the decreases in these responses. ELISpot showed that, contrasting with the central-memory responses above, infliximab did not affect effector-memory INF-γ-releasing T-cell numbers. CONCLUSIONS: Infliximab affected some, but not all aspects of the in vitro antituberculosis immune responses tested. The preserved effector-memory responses, putatively related to exposure to environmental mycobacteria, may help to explain the lower than expected susceptibility to tuberculosis reactivation in our setting.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Mycobacterium tuberculosis/imunologia , Psoríase/tratamento farmacológico , Adulto , Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Humanos , Infliximab , Interferon gama/sangue , Interleucina-10/sangue , Masculino , Psoríase/imunologia , Estatísticas não Paramétricas , Teste Tuberculínico , Fator de Necrose Tumoral alfa/sangue
6.
Clin Exp Immunol ; 167(1): 129-36, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22132892

RESUMO

The disturbed cytokine-chemokine network could play an important role in the onset of diseases with inflammatory processes such as chronic idiopathic urticaria (CIU). Our main objectives were to evaluate the relation between proinflammatory chemokine serum levels from CIU patients and their response to autologous skin test (ASST) and basophil histamine release (BHR). We also aimed to assess the chemokine secretion by peripheral blood mononuclear cells (PBMC) upon polyclonal stimulus and to evaluate chemokine C-C ligand 2/C-X-C chemokine 8 (CCL2/CXCL8) and Toll-like receptor-4 (TLR-4) expression in monocytes. We observed significantly higher serum levels of the CXCL8, CXCL9, CXCL10 and CCL2 in CIU patients compared to the healthy group, regardless of the BHR or ASST response. The basal secretion of CCL2 by PBMC or induced by Staphylococcus aureus enterotoxin A (SEA) was higher in CIU patients than in the control group, as well as for CXCL8 and CCL5 secretions upon phytohaemagglutinin stimulation. Also, up-regulation of CCL2 and CXCL8 mRNA expression was found in monocytes of patients upon SEA stimulation. The findings showed a high responsiveness of monocytes through CCL2/CXCL8 expression, contributing to the creation of a proinflammatory environment in CIU.


Assuntos
Quimiocina CCL2/biossíntese , Interleucina-8/biossíntese , Leucócitos Mononucleares/metabolismo , Monócitos/metabolismo , Urticária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Teste de Degranulação de Basófilos , Quimiocina CCL2/genética , Quimiocina CCL2/fisiologia , Quimiocinas/sangue , Doença Crônica , Enterotoxinas/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação , Interleucina-8/genética , Interleucina-8/fisiologia , Leucócitos Mononucleares/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Fito-Hemaglutininas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Testes Cutâneos , Receptor 4 Toll-Like/biossíntese , Receptor 4 Toll-Like/genética , Regulação para Cima/efeitos dos fármacos , Urticária/sangue , Urticária/imunologia , Adulto Jovem
7.
Clinics ; 62(Suppl. 3): S99-S99, Sept. 2009.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1062101
9.
Clinics ; 62(Suppl. 3): S108-S108, Sept. 2009.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1062106
11.
Rev. Inst. Med. Trop. Säo Paulo ; 51(supl. 15): 55-55, set. 2009.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1066616

Assuntos
Imunidade
12.
Scand J Immunol ; 69(2): 169-73, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19170966

RESUMO

Type 1, X-linked Hyper-IgM syndrome (HIGM1) is caused by mutations in the gene encoding the CD154 protein, also known as CD40 ligand (CD40LG). CD40L is expressed in activated T cells and interacts with CD40 receptor expressed on B lymphocytes and dendritic cells. Affected patients present cellular and humoral immune defects, with infections by intracellular, opportunistic and extracellular pathogens. In the present study we investigated the molecular defects underlying disease in four patients with HIGM1. We identified four distinct CD40L mutations, two of them which have not been previously described. P1 harboured the novel p.G227X mutation which abolished CD40L expression. P2 had a previously described frame shift deletion in exon 2 (p.I53fsX65) which also prevented protein expression. P3 demonstrated the previously known p.V126D change in exon 4, affecting the TNF homology (TNFH) domain. Finally, P4 evidenced the novel p.F229L mutation also located in the TNFH domain. In silico analysis of F229L predicted the change to be pathological, affecting the many hydrophobic interactions of this residue. Precise molecular diagnosis in HIGM syndrome allows reliable detection of carriers, making genetic counselling and prenatal diagnosis possible.


Assuntos
Ligante de CD40/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Hipergamaglobulinemia/genética , Imunoglobulina M/sangue , Mutação , Sequência de Aminoácidos , Ligante de CD40/análise , Ligante de CD40/química , Humanos , Dados de Sequência Molecular , Linfócitos T/química
13.
Br J Dermatol ; 158(5): 979-86, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18341658

RESUMO

BACKGROUND: Basophils and mast cells are the main target cells in chronic idiopathic urticaria (CIU). Besides the basopenia, intrinsic defects of the anti-IgE cross-linking signalling pathway of basophils have been described in CIU. OBJECTIVES: We sought to investigate the profile of expression of activation markers on basophils of patients with CIU and to explore the effect of interleukin (IL)-3 priming upon anti-IgE cross-linking stimuli through expression of activation markers and basophil histamine releasability. METHODS: Evaluation of the surface expression of FcepsilonRIalpha, CD63, CD203c and CD123 on whole blood basophils of patients with CIU undergoing autologous serum skin test (ASST) was performed by flow cytometry. The effect of pretreatment with IL-3 in the anti-IgE response was analysed by the expression of basophil activation markers and histamine release using enzyme-linked immunosorbent assay. RESULTS: Blood basophils of patients with CIU were reduced in number and displayed increased surface expression of FcepsilonRIalpha, which was positively correlated with the IgE serum levels. Upregulation of expression of both surface markers CD203c and CD63 was verified on basophils of patients with CIU, regardless of ASST response. High expression of IL-3 receptor on basophils was detected only in ASST+ patients with CIU. Pretreatment with IL-3 upregulated CD203c expression concomitantly with the excreting function of blood basophils and induced a quick hyper-responsiveness to anti-IgE cross-linking on basophils of patients with CIU compared with healthy controls. CONCLUSIONS: Basophils of patients with CIU showed an activated profile, possibly due to an in vivo priming. Functionally, basophils have high responsiveness to IL-3 stimulation, thereby suggesting that defects in the signal transduction pathway after IgE cross-linking stimuli are recoverable in subjects with chronic urticaria.


Assuntos
Antígenos CD/metabolismo , Basófilos/efeitos dos fármacos , Liberação de Histamina/efeitos dos fármacos , Imunoglobulina E/imunologia , Interleucina-3/farmacologia , Urticária/imunologia , Adulto , Idoso , Basófilos/imunologia , Biomarcadores/análise , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Receptores de IgE/metabolismo
14.
AIDS Res Hum Retroviruses ; 23(7): 906-12, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17678475

RESUMO

Chemokine receptors are used by HIV-1 for entry into CD4+ T cells. The beta-chemokines are capable of inhibiting HIV replication. This study measured beta-chemokine macrophage inflammatory protein (MIP)-1alpha and MIP-1beta levels and determined the CCR5 and CXCR4 expression on T cells in HIV-1-infected patients treated with HAART. The time of known HIV infection and time of HAART use were similar between failure and successful groups. The CD4+ T cell nadir was 163 vs. 251 cells/mm3, p = 0.07, for failure and successful groups, respectively. The successfully treated group, when compared with the failure group, had a higher median CD4+ T cells count (667 vs. 257 cells/mm3; p = 0.003) as well as higher spontaneous MIP-1alpha (median of 4390 vs. 802 pg/ml, p = 0.03) and MIP-1beta (median of 2416 vs. 1117 pg/ml, p = 0.001) levels. The untreated patients had a higher number and intensity of CCR5- and CXCR4-expressing T cells. Higher levels of chemokines were not related to nadir CD4+ T and current CD8+ T cell counts. Successfully treated patients were able to produce higher amounts of beta-chemokines and normalize the coreceptor overexpression on T cells. These findings may have clinical implications, such as a new strategy of using chemokines as adjuvants in anti-HIV therapy.


Assuntos
Terapia Antirretroviral de Alta Atividade , Quimiocinas CC/metabolismo , Infecções por HIV , HIV-1/imunologia , Adulto , Estudos de Casos e Controles , Quimiocina CCL3 , Quimiocina CCL4 , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Resultado do Tratamento
15.
Scand J Immunol ; 65(6): 577-80, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17523951

RESUMO

The present study evaluated the in vitro response to different mitogens and a candidin antigen (CMA) in Human T-cell lymphotropic virus type 1 (HTLV-1) and co-infected HIV-1/HTLV-1 patients, to identify if this co-infection may modify the spontaneous lymph proliferative response. Peripheral blood mononuclear cells from 72 healthy seronegative controls, 75 asymptomatic HTLV-1-infected carriers, 42 HAM/TSP cases, 33 solely HIV-1-infected subjects and 24 HIV-1/HTLV-1 patients were assayed in the presence and absence of mitogens (PHA, PWM and OKT3) and CMA. The HAM/TSP group had the highest proliferation rate at 3 and 6 days after culture. HAM/TSP cases showed decreased response to PHA, compared with asymptomatic HTLV-1 subjects, and most important, the co-infected HIV-1/HTLV-1 cases presented a similar response to HTLV-1-infected subjects after 3 days of culture. The singles HIV-1-infected group had decreased in vitro response. It appears that during co-infection, the HTLV-1 regulatory proteins overwhelm the action of HIV-1 regulatory proteins.


Assuntos
Portador Sadio/imunologia , Proliferação de Células/efeitos dos fármacos , Infecções por HIV/imunologia , Infecções por HTLV-I/imunologia , Leucócitos Mononucleares/imunologia , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/virologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Portador Sadio/sangue , Células Cultivadas , Comorbidade , Infecções por HIV/epidemiologia , Infecções por HTLV-I/sangue , Infecções por HTLV-I/epidemiologia , Humanos , Contagem de Linfócitos , Mitógenos/farmacologia , Mielite/sangue , Mielite/epidemiologia , Mielite/imunologia , Paraparesia Espástica Tropical/sangue , Paraparesia Espástica Tropical/epidemiologia
16.
Braz J Med Biol Res ; 40(3): 301-4, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334525

RESUMO

The purpose of the present study was to compare the sensitivity and specificity of V3 enzyme immunoassay (solid phase EIA and EIA inhibition) and restriction fragment length polymorphism (RFLP) with the DNA sequencing "gold standard" to identify the Brazilian HIV-1 variants of subtype B and B"-GWGR. Peripheral blood mononuclear cells were collected from 61 HIV-1-infected individuals attending a clinic in São Paulo. Proviral DNA was amplified and sequentially cleaved with the Fok I restriction enzyme. Plasma samples were submitted to a V3-loop biotinylated synthetic peptide EIA. Direct partial DNA sequencing of the env gene was performed on all samples. Based on EIA results, the sensitivity for detecting B-GPGR was 70%, compared to 64% for the Brazilian variant B"-GWGR while, the specificity of B-GPGR detection was 85%, compared to 88% for GWGR. The assessment of RFLP revealed 68% sensitivity and 94% specificity for the B-GPGR strain compared to 84 and 90% for the B"-GWGR variant. Moreover, direct DNA sequencing was able to detect different base sequences corresponding to amino acid sequences at the tip of the V3 loop in 22 patients. These results show a similar performance of V3 serology and RLFP in identifying the Brazilian variant GWGR. However, V3 peptide serology may give indeterminate results. Therefore, we suggest that V3 serology be used instead of DNA sequencing where resources are limited. Samples giving indeterminate results by V3 peptide serology should be analyzed by direct DNA sequencing to distinguish between B-GPGR and the Brazilian variant B"-GWGR.


Assuntos
Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Leucócitos Mononucleares/virologia , Fragmentos de Peptídeos/genética , Adulto , Sequência de Aminoácidos , DNA Viral/análise , Feminino , HIV-1/classificação , HIV-1/genética , Humanos , Técnicas Imunoenzimáticas , Masculino , Polimorfismo de Fragmento de Restrição , Provírus/genética , Sensibilidade e Especificidade , Sorotipagem
17.
Braz. j. med. biol. res ; 40(3): 301-304, Mar. 2007. ilus, tab
Artigo em Inglês | LILACS | ID: lil-441754

RESUMO

The purpose of the present study was to compare the sensitivity and specificity of V3 enzyme immunoassay (solid phase EIA and EIA inhibition) and restriction fragment length polymorphism (RFLP) with the DNA sequencing "gold standard" to identify the Brazilian HIV-1 variants of subtype B and B"-GWGR. Peripheral blood mononuclear cells were collected from 61 HIV-1-infected individuals attending a clinic in São Paulo. Proviral DNA was amplified and sequentially cleaved with the Fok I restriction enzyme. Plasma samples were submitted to a V3-loop biotinylated synthetic peptide EIA. Direct partial DNA sequencing of the env gene was performed on all samples. Based on EIA results, the sensitivity for detecting B-GPGR was 70 percent, compared to 64 percent for the Brazilian variant B"-GWGR while, the specificity of B-GPGR detection was 85 percent, compared to 88 percent for GWGR. The assessment of RFLP revealed 68 percent sensitivity and 94 percent specificity for the B-GPGR strain compared to 84 and 90 percent for the B"-GWGR variant. Moreover, direct DNA sequencing was able to detect different base sequences corresponding to amino acid sequences at the tip of the V3 loop in 22 patients. These results show a similar performance of V3 serology and RLFP in identifying the Brazilian variant GWGR. However, V3 peptide serology may give indeterminate results. Therefore, we suggest that V3 serology be used instead of DNA sequencing where resources are limited. Samples giving indeterminate results by V3 peptide serology should be analyzed by direct DNA sequencing to distinguish between B-GPGR and the Brazilian variant B"-GWGR.


Assuntos
Humanos , Masculino , Feminino , Adulto , /genética , Infecções por HIV/virologia , HIV-1 , Leucócitos Mononucleares/virologia , Fragmentos de Peptídeos/genética , Sequência de Aminoácidos , DNA Viral/análise , HIV-1 , Técnicas Imunoenzimáticas , Polimorfismo de Fragmento de Restrição , Provírus/genética , Sensibilidade e Especificidade , Sorotipagem
18.
Rev. Soc. Bras. Med. Trop ; 39(Suppl. II): 101-101, set. 2006.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1066735
19.
Mem. Inst. Oswaldo Cruz ; 101(3): 273-276, May 2006. tab
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: lil-431725

RESUMO

The product of human T-cell lymphotropic virus type 1 (HTLV-1) tax gene has a transactivating effect of the viral and cellular gene expression. Genetic variations in this gene have been correlated with differences in clinical outcomes. Based upon its diversity, two closely related substrains, namely tax A and tax B, have been described. The tax A substrain has been found at a higher frequency among human T-cell leukemia virus type 1 (TSP/HAM) patients than among healthy HTLV-I-infected asymptomatic subjects in Japan. In this study, we determined the distribution of tax substrains in HTLV-I-infected subjects in the city of São Paulo, Brazil. Using the ACCII restriction enzyme site, we detected only tax A substrain from 48 TSP/HAM patients and 28 healthy HTLV-I carriers. The sequenced tax genes from nine TSP/HAM patients and five asymptomatic HTLV-I carriers showed a similar pattern of mutation, which characterizes tax A. Our results indicate that HTLV-I tax subtypes have no significant influences on TSP/HAM disease progression. Furthermore, monophyletic introduction of HTLV-I to Brazil probably occurred during the African slave trade many years ago.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Mutação , Paraparesia Espástica Tropical/virologia , Produtos do Gene tax/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Variação Genética , Polimorfismo de Fragmento de Restrição
20.
Braz J Med Biol Res ; 38(11): 1643-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16258633

RESUMO

To evaluate the human T-cell lymphotropic virus type I (HTLV-I) proviral DNA load among asymptomatic HTLV-I-infected carriers and patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), real time PCR using TaqMan probes for the pol gene was performed in two million peripheral blood mononuclear cells (PBMC). The albumin gene was the internal genomic control and MT2 cells were used as positive control. The results are reported as copies/10,000 PBMC, and the detection limit was 10 copies. A total of 89 subjects (44 HAM/TSP and 45 healthy HTLV-I-infected carriers) followed up at the Institute of Infectious Diseases "Emilio Ribas" and in the Neurology Division of Hospital of Clínicas were studied. The asymptomatic HTLV-I-infected carriers had a median number of 271 copies (ranging from 5 to 4756 copies), whereas the HAM/TSP cases presented a median of 679 copies (5-5360 copies) in 10,000 PBMC. Thus, HAM/TSP patients presented a significantly higher HTLV-I proviral DNA load than healthy HTLV-I carriers (P = 0.005, one-way Mann-Whitney test). As observed in other persistent infections, proviral DNA load quantification may be an important tool for monotoring HTLV-I-infected subjects. However, long-term follow-up is necessary to validate this assay in the clinical setting.


Assuntos
DNA Viral/análise , Vírus Linfotrópico T Tipo 1 Humano/genética , Paraparesia Espástica Tropical/virologia , Provírus/genética , Estudos de Casos e Controles , DNA Viral/genética , DNA Viral/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Paraparesia Espástica Tropical/imunologia , Reação em Cadeia da Polimerase , Provírus/imunologia , Carga Viral
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