Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.324
Filtrar
1.
An Bras Dermatol ; 99(5): 680-687, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38851894

RESUMO

BACKGROUND: Anti-desmoglein (Dsg)1 is produced in pemphigus foliaceus (PF), affecting exclusively the skin. Pemphigus vulgaris (PV) shows the production of anti-Dsg3 in the mucosal form, and anti-Dsg1 and 3 in the mucocutaneous form. Anti-Dsg3 autoantibodies have been rarely reported in PF. OBJECTIVES: To determine the factors associated with the production and pathogenicity of anti-Dsg3 in PF. METHODS: Comparative analytical study of three patients groups: 16 PF-anti-Dsg3+, and 42 PF-anti-Dsg3(-) and 22 PV treatment-naïve cases. Serum was used in the anti-Dsg1 and 3 ELISA, and in immunoblotting (IB) with human epidermis extract. The expression of Dsg1 and 3 in paraffin sections was analyzed by immunohistochemistry (IHC). HLA-DRB1 alleles were compiled from a database. RESULTS: In the PF-anti-Dsg3+ group: age range similar to that of the PV group (p > 0.9999); predominance of the generalized form of PF (p = 0.002); anti-Dsg3 titers lower than those of PV (p < 0.0001); IB confirmed Dsg3 identification in one (8.33%) of 12 patients; IHC showed exclusive cytoplasmic internalization of Dsg1; HLA-DRB1 alleles of susceptibility to PF, with the absence of alleles associated with PV, in the five typed patients. STUDY LIMITATIONS: Most of the patients in the PF-anti-Dsg3+ group were undergoing treatment. CONCLUSION: The presence of anti-Dsg3 antibodies in PF was related to older age (comparable to that of PV) and the generalized form of PF. The non-pathogenicity of anti-Dsg3 antibodies in PF can be attributed to the low serum anti-Dsg3 titers, the lack of Dsg3 internalization as detected by IHC, and the absence of PV-associated HLA-DRB1 alleles.


Assuntos
Autoanticorpos , Desmogleína 1 , Desmogleína 3 , Imuno-Histoquímica , Pênfigo , Humanos , Pênfigo/imunologia , Desmogleína 3/imunologia , Autoanticorpos/imunologia , Autoanticorpos/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Desmogleína 1/imunologia , Ensaio de Imunoadsorção Enzimática , Adulto Jovem , Immunoblotting , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Idoso de 80 Anos ou mais , Adolescente
2.
PLoS Negl Trop Dis ; 17(8): e0011535, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37540724

RESUMO

Endemic in Brazil, visceral leishmaniasis (VL) is a zoonotic infection that is among the most important parasitic diseases transmitted by vectors. Dogs are the main reservoirs of canine leishmaniasis (CanL) and their identification is used in some countries as part of disease prevention and control measures in the canine and human population. In this context, serological tests are necessary, composed of antigens capable of correctly identifying infected dogs, minimizing the number of false-negative cases. This study aimed to identify more immunoreactive peptides derived from two previously described whole proteins (rDyn-1 and rKDDR-plus) and compare their performance to the control antigens rK39 and the crude extract for the detection of dogs infected with L. infantum, especially the asymptomatic ones. The three selected peptides and a mixture of them, along with the rDyn-1, rKDDR-plus, rK39, and crude extract antigens were evaluated using indirect ELISA with sera samples from 186 dogs with CanL, being asymptomatic (n = 50), symptomatic (n = 50), co-infected (n = 19), infected with Babesia sp. (n = 7), Ehrlichia sp. (n = 6), T. cruzi (n = 20) and uninfected (n = 34). The results showed that the rDyn-1 protein and the peptide mixture had the highest sensitivity (100% and 98.32%, respectively) and specificity (97.01 and 98.51, respectively). A high degree of kappa agreement was found for rDyn-1 protein (0.977), mixed peptides (0.965), rKDDR-plus protein (0.953), K-plus peptide 1 (0.930) and Dyn-1 peptide (0.893). The mixture of peptides showed the highest likelihood (65.87). The ELISA using the mixture of peptides and the rDyn-1 protein showed high performance for CanL serodiagnosis. More mix combinations of the peptides and additional extended field tests with a larger sample size are recommended.


Assuntos
Doença de Chagas , Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Humanos , Cães , Animais , Antígenos de Protozoários , Sensibilidade e Especificidade , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Leishmaniose Visceral/epidemiologia , Peptídeos , Immunoblotting , Oligopeptídeos , Ensaio de Imunoadsorção Enzimática/métodos , Testes Sorológicos/métodos , Doenças do Cão/epidemiologia , Anticorpos Antiprotozoários
3.
Rev. méd. Chile ; 151(4): 461-468, abr. 2023. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1560202

RESUMO

INTRODUCTION: For the diagnosis of liver diseases, clinical criteria, biochemical, immunological and histological parameters are included. The autoimmune panel is an immunoblot that contemplates the detection of antibodies against 9 different hepatic antigens, which could guide the diagnosis of these pathologies. OBJECTIVE: To describe the usefulness of the autoimmune panel in the diagnosis of liver diseases. Methods: Observational, descriptive study. All autoimmune panels performed between January 2020 and August 2021 (n = 279) were reviewed, and the ones with positive result selected (n = 101). Clinical records were reviewed, including: clinical, biochemical, immunological and histological characteristics. Diagnosis was determined by clinical suspicion (clinical, biochemical and immunological parameters), only through autoimmune panel, and according to liver biopsy in available cases. RESULTS: 45 patients with complete clinical history were included in the analysis; 82% women, median age 58 years (16-79). Clinical suspicions included autoimmune hepatitis (AIH) in 12 patients (27%), primary biliary cholangitis (PBC) in 10 patients (22%), overlap syndrome (AIH/PBC) in 17 (38%), and others in 6 (13%). The diagnosis of PBC was confirmed by autoimmune panel in 9/10 and 11/17 patients with clinical suspicion of PBC and HAI/PBC, respectively. Of the 27 patients with initial clinical suspicion of PBC, 14 had negative AMA and AMA-M2 (6 had Sp100 and 5 gp210 as the only markers and 3 had positive Sp100 and PML). In 10/14 patients, the diagnosis was confirmed by panel and/or compatible liver biopsy. CONCLUSION: The autoimmune panel turns out to be a useful diagnostic tool for liver diseases, especially PBC in isolation or in overlap syndrome.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Autoanticorpos/sangue , Immunoblotting/métodos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/imunologia , Hepatite Autoimune/sangue , Hepatopatias/diagnóstico , Hepatopatias/imunologia , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Doenças Autoimunes/sangue , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/sangue
4.
Acta Trop ; 238: 106782, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455637

RESUMO

Leptospirosis is an infectious, zoonotic disease of worldwide distribution, the cause of which is infection by pathogenic Leptospira. In Chile, dairy cattle are recognized a significant source in the maintenance and transmission of this infection, which causes economic losses and represents an infection threat to workers in the dairy industry. The infection is underestimated in cattle, due to the lack of clinical, pathognomonic signs, as well as the low efficiency of current diagnostic techniques. In this study, we developed antigen ELISA and dot blot assays, based on polyclonal antibodies, to detect pathogenic Leptospira in the urine samples of dairy cattle. The proposed tests showed an acceptable diagnostic accuracy, based on an analytical sensitivity of 1·104 Leptospira per mL for ELISA, and 3.2·103 for dot blot. These results corresponded with those obtained by qPCR, and the use of urine samples allowed us to propose new diagnostic alternatives for pathogenic Leptospira infection at a low cost, which can provide information on active infection status, which is a key element in control programs both at individual and herd level.


Assuntos
Leptospira , Leptospirose , Animais , Bovinos , Leptospirose/diagnóstico , Leptospirose/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Immunoblotting , Anticorpos Antibacterianos
5.
Rev Med Chil ; 151(4): 461-468, 2023 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-38687521

RESUMO

INTRODUCTION: For the diagnosis of liver diseases, clinical criteria, biochemical, immunological and histological parameters are included. The autoimmune panel is an immunoblot that contemplates the detection of antibodies against 9 different hepatic antigens, which could guide the diagnosis of these pathologies. OBJECTIVE: To describe the usefulness of the autoimmune panel in the diagnosis of liver diseases. METHODS: Observational, descriptive study. All autoimmune panels performed between January 2020 and August 2021 (n = 279) were reviewed, and the ones with positive result selected (n = 101). Clinical records were reviewed, including: clinical, biochemical, immunological and histological characteristics. Diagnosis was determined by clinical suspicion (clinical, biochemical and immunological parameters), only through autoimmune panel, and according to liver biopsy in available cases. RESULTS: 45 patients with complete clinical history were included in the analysis; 82% women, median age 58 years (16-79). Clinical suspicions included autoimmune hepatitis (AIH) in 12 patients (27%), primary biliary cholangitis (PBC) in 10 patients (22%), overlap syndrome (AIH/PBC) in 17 (38%), and others in 6 (13%). The diagnosis of PBC was confirmed by autoimmune panel in 9/10 and 11/17 patients with clinical suspicion of PBC and HAI/PBC, respectively. Of the 27 patients with initial clinical suspicion of PBC, 14 had negative AMA and AMA-M2 (6 had Sp100 and 5 gp210 as the only markers and 3 had positive Sp100 and PML). In 10/14 patients, the diagnosis was confirmed by panel and/or compatible liver biopsy. CONCLUSION: The autoimmune panel turns out to be a useful diagnostic tool for liver diseases, especially PBC in isolation or in overlap syndrome.


Assuntos
Autoanticorpos , Hepatite Autoimune , Immunoblotting , Hepatopatias , Humanos , Feminino , Autoanticorpos/sangue , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Adolescente , Adulto Jovem , Immunoblotting/métodos , Hepatite Autoimune/imunologia , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/sangue , Hepatopatias/imunologia , Hepatopatias/diagnóstico , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/sangue , Doenças Autoimunes/imunologia , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/sangue
6.
Transbound Emerg Dis ; 69(5): e2994-e3006, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35801561

RESUMO

Toxocariasis is an infection caused by the round worms Toxocara canis and Toxocara cati. It occurs worldwide though it is more prevalent in developing countries. For the diagnosis of toxocariasis, the most used method is the indirect enzyme-linked immunosorbent assay (indirect ELISA), based on the detection of specific antibodies using the excreted/secreted products from T. canis larvae (TES) as antigens, but it cross-reacts with several helminth infections. For this reason, there is a need to investigate species-specific immunoreactive proteins, which can be used for the development of a more sensitive and specific diagnosis. This study aims to investigate immunoreactive protein candidates to be used for the development of a more sensitive and specific diagnosis of Toxocara spp. infection in humans. We have used immunoblotting and mass spectrometry to select four Toxocara canis immunoreactive proteins that were recombinantly expressed in bacteria and evaluated as potential new diagnostic antigens (rMUC3, rTES 26, rTES32 and rCTL4). The recognition of these recombinant proteins by total serum IgG and IgG4 was assayed using the purified proteins in an isolated manner or in combination. The IgG ELISAs performed with individual recombinant antigens reached values of sensitivity and specificity that ranged from 91.7% to 97.3% and 94.0% to 97.9%, respectively. Among the analyses, the IgG4 immunoassay was proven to be more effective, revealing a sensitivity that ranged from 88.8% to 98.3% and a specificity of 97.8%-97.9%. The IgG4 ELISA was shown to be more effective and presented no cross-reactivity when using combinations of the rTES 26 and rCTL4 recombinant proteins. The combination of these two molecules achieved 100% sensitivity and specificity. The use of only two recombinant proteins can contribute to improve the current panorama of toxocariasis immunodiagnosis for, with a better optimization and reduced cost.


Assuntos
Toxocara canis , Toxocaríase , Animais , Antígenos de Helmintos , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Immunoblotting/veterinária , Imunoglobulina G , Testes Imunológicos/veterinária , Proteômica , Proteínas Recombinantes , Toxocara , Toxocaríase/diagnóstico
7.
Hematol., Transfus. Cell Ther. (Impr.) ; 43(4): 410-416, Oct.-Dec. 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1350825

RESUMO

ABSTRACT Background: The screening of Trypanosoma cruzi-infected blood donors using two serological techniques frequently leads to conflicting results. This fact prompted us to evaluate the diagnostic performance of four "in-house" immunodiagnostic tests and two commercially available enzyme-linked immunosorbent assays (ELISAs). Material and Methods: One hundred and seventy-nine blood donors, whose screening for Chagas disease was doubtful, underwent three in-house ELISAs, one in-house immunoblotting test (TESA-blot), and two commercial ELISAs (bioMérieux and Wiener) in an attempt to define the presence or absence of infection. Simultaneously, 29 donors with previous positive results from three conventional serological tests and 30 donors with constant negative results were evaluated. Results: The ELISA-Wiener showed the highest rate in sensitivity (98.92%) and the ELISA-bioMérieux, the highest specificity (99.45%), followed by the TESA-blot, which showed superior performance, with lower false-negative (2.18%) and false-positive (1.12%) rates. In series, the combination composed of the TESA-blot and ELISA-bioMérieux showed slightly superior performance, with trifunctional protein deficiency (TFP) = 0.01%. Conclusion: Our study confirms the high sensitivity and specificity of commercial kits. To confirm the presence or absence of T. cruzi infection, the combination of TESA-blot and ELISA-bioMérieux may be suggested as the best alternative. Individually, the TESA-blot performed the closest to the gold standard; however, it is not commercially available.


Assuntos
Humanos , Trypanosoma cruzi , Testes Imunológicos , Doença de Chagas , Doadores de Sangue , Ensaio de Imunoadsorção Enzimática , Immunoblotting
8.
Am J Trop Med Hyg ; 104(6): 2091-2096, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33939643

RESUMO

Cutaneous leishmaniasis (CL) is firmly established in South America. We aimed to assess the detection of IgG antibodies against 14 and/or 16 kDa antigens by immunoblot (IB) for CL serological diagnosis in French Guiana, an area where many endemic pathogens could interfere with it. This study was performed retrospectively on sera from 141 patients at the Cayenne tertiary hospital: 30 were patients with confirmed CL, 71 were diagnosed with various other endemic pathogens, 11 were diagnosed with an autoimmune disease, and 29 controls had no history of CL. Antibodies bound to the 14 and/or 16 kDa antigens in 27 of the 30 CL patients' sera and in 39 of the 111 non-CL patients' sera (26 from the infectious diseases group, four from the autoimmune diseases group, and nine from the dermatology department). The method tested showed a high sensitivity (90%) and a low specificity (66%), and a diagnosis odds ratio of 17.5 (95% CI [4.6-78.0]). This IB may be helpful to exclude the diagnosis of CL, prompting physicians to look for another diagnosis in the case of a negative IB.


Assuntos
Anticorpos Antiprotozoários/sangue , Immunoblotting/métodos , Immunoblotting/normas , Imunoglobulina G/sangue , Leishmania/imunologia , Leishmaniose Cutânea/diagnóstico , Adolescente , Adulto , Antígenos de Protozoários/imunologia , Doenças Endêmicas , Feminino , Guiana Francesa , Humanos , Leishmania/classificação , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Centros de Atenção Terciária/estatística & dados numéricos , Adulto Jovem
9.
Electron. j. biotechnol ; 51: 50-57, May. 2021. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1343384

RESUMO

BACKGROUND: Molecular brain therapies require the development of molecular switches to control gene expression in a limited and regulated manner in time and space. Light-switchable gene systems allow precise control of gene expression with an enhanced spatio-temporal resolution compared to chemical inducers. In this work, we adapted the existing light-switchable Light-On system into a lentiviral platform, which consists of two modules: (i) one for the expression of the blue light-switchable transactivator GAVPO and (ii) a second module containing an inducible-UAS promoter (UAS) modulated by a light-activated GAVPO. RESULTS: In the HEK293-T cell line transfected with this lentiviral plasmids system, the expression of the reporter mCherry increased between 4 to 5 fold after light induction. A time expression analysis after light induction during 24 h revealed that mRNA levels continuously increased up to 9 h, while protein levels increased throughout the experiment. Finally, transduction of cultured rat hippocampal neurons with this dual Light-On lentiviral system showed that CDNF, a potential therapeutic trophic factor, was induced only in cells exposed to blue light. CONCLUSIONS: In conclusion, the optimized lentiviral platform of the Light-On system provides an efficient way to control gene expression in neurons, suggesting that this platform could potentially be used in biomedical and neuroscience research, and eventually in brain therapies for neurodegenerative diseases.


Assuntos
Regulação da Expressão Gênica , Optogenética/métodos , Luz , Neurônios/metabolismo , Immunoblotting , Expressão Gênica , Imunofluorescência , Lentivirus
10.
Am J Trop Med Hyg ; 104(6): 2038-2041, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33872212

RESUMO

Strongyloides stercoralis is a soil-transmitted nematode that can cause life-threatening conditions in immunocompromised persons. In the United States, strongyloidiasis should be considered mainly in immigrants, refugees, or travelers. The confirmatory laboratory diagnosis is usually performed by detecting larvae from the stool, duodenal material, and sputum. In persons who are immunocompromised with severe strongyloidiasis, adult worms and eggs can be detected from duodenal material. For serological diagnosis, most assays use crude antigens to detect anti-S. stercoralis IgG. Recently, recombinant proteins such as rSs-NIE-1 and rSs-IR have been used to detect IgG antibodies. We used rSs-NIE-1 and rSs-IR recombinant antigens to develop a biplex Western blot assay to detect the IgG4 antibody in individuals with strongyloidiasis. The sensitivities of rSs-NIE-1 and rSs-IR were 97.4% and 90.8%, respectively, whereas the specificities were 97.6% and 98%, respectively. In conclusion, the biplex rSs-NIE-1 and rSs-IR immunoblot performs well in detecting IgG4 antibody in S. stercoralis-infected persons.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Immunoblotting/métodos , Strongyloides stercoralis/imunologia , Estrongiloidíase/diagnóstico , Animais , Antígenos de Helmintos/genética , Fezes/parasitologia , Humanos , Immunoblotting/normas , Imunoglobulina G/sangue , Larva/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Strongyloides stercoralis/química , Estrongiloidíase/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA