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1.
Medicine (Baltimore) ; 98(41): e17566, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593141

RESUMO

RATIONALE: Coexistence of Fabry disease and IgM nephropathy is rare. The varying severity and unapparent clinical manifestation of Fabry disease makes it difficult to recognize when coexisting with another more prevalent cause of nephropathy requiring electron microscopy and genetic testing to confirm their coexistence. PATIENT CONCERNS: A 54-year-old female presented with proteinuria without any clinical signs or family history of Fabry disease. DIAGNOSES: Immunostaining of the renal biopsy identified mesangial IgM deposition diagnosing it as IgM nephropathy. The light microscopy indicated prominent vacuolization of podocytes. Further examination of toluidine blue stained semi-thin sections and electron microscopy revealed blue bodies and myelin bodies in the cytoplasm of podocytes, respectively. Mutation analysis detected missense mutation establishing the diagnosis of coexisting Fabry disease. INTERVENTIONS: The patient was treated with angiotensin-converting enzyme inhibitors. Enzyme replacement therapy was not administered due to financial constraints. OUTCOMES: After 2 months of treatment the patient demonstrated urine protein to creatinine ratio of 0.21 g/g. LESSONS: Identifying coexistence of Fabry disease with other nephropathy requires meticulous pathologic investigations including electron microscopy especially when Fabry disease presents with atypical phenotype.


Assuntos
Doença de Fabry/complicações , Glomerulonefrite/diagnóstico , Imunoglobulina M/imunologia , Podócitos/ultraestrutura , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Terapia de Reposição de Enzimas/economia , Doença de Fabry/diagnóstico , Doença de Fabry/genética , Doença de Fabry/patologia , Feminino , Glomerulonefrite/complicações , Glomerulonefrite/tratamento farmacológico , Glomerulonefrite/patologia , Humanos , Microscopia Eletrônica/métodos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Podócitos/patologia , Proteinúria/diagnóstico , Proteinúria/etiologia , Resultado do Tratamento
2.
Cell Physiol Biochem ; 53(3): 453-464, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448885

RESUMO

BACKGROUND/AIMS: Eryptosis, the suicidal death of red blood cells (RBCs), is characterized by phosphatidylserine (PS) exposure at the cell surface. It can be catalysed by a variety of abnormal conditions and diseases. Until now, the many questions surrounding the physiology and pathophysiology of eryptosis have not been sufficiently answered. Recently, we demonstrated IgM and IgA autoantibodies (aab) to induce PS exposure on circulating RBCs of patients with autoimmune haemolytic anaemia (AIHA). However, it remained unclear how these aab lead to eryptosis. METHODS: Serum and plasma samples from patients with clinically relevant AIHA of cold type were used to induce eryptosis in O RBCs. Serum containing fresh complement from healthy donors, antibodies to complement component, and complement factor depleted sera were added to examine the influence of the complement on PS-exposure. RBC bound annexin V PE were analysed by flow cytometry. RESULTS: Eryptosis related to IgM aab was found to be dependent on complement activation and could be effectively inhibited by EDTA, serum heat inactivation and anti-C5. PS exposure increased with sequential activation of the sublytic terminal complement components C5b6, C5b-7 and was most significant at the C5b-8 stage. A decrease was observed following the formation of the lytic membrane attack complex C5b-9, either because of lysis of eryptotic RBCs or because of inhibition of eryptosis by C9. CONCLUSION: Our findings reflect new aspects on RBC destruction in AIHA as well the impact of the terminal complement complexes on the RBC membrane. The striking differences to nucleated cell apoptosis may even have physiological meaning of RBC acting as a buffer of the complement system.


Assuntos
Anemia Hemolítica Autoimune/patologia , Autoanticorpos/farmacologia , Proteínas do Sistema Complemento/metabolismo , Eriptose/efeitos dos fármacos , Imunoglobulina M/imunologia , Anemia Hemolítica Autoimune/sangue , Ativação do Complemento/efeitos dos fármacos , Complemento C5/metabolismo , Ácido Edético/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Fosfatidilserinas/farmacologia
3.
J Microbiol ; 57(9): 821-827, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452045

RESUMO

Most commercialized virus-like particle (VLP) vaccines use aluminum salt as adjuvant, even though VLPs provoke adequate antibody responses without adjuvant. We do not have detailed knowledge of how adjuvant affects the profile of anti-VLP antibodies. Meanwhile, there is evidence that differences between vaccination protocols influence the glycosylation of antibodies, which may alter their effector functions. In the present study a murine model was used to investigate the effects of dosing schedule and adjuvant on the antibody profiles and glycosylation levels of antigen-specific antibody responses to human papillomavirus type 16 L1 (HPV16 L1) VLPs. Mice received subcutaneously 2,000 ng of antigen divided into 4 or 7 doses. The HPV16 L1 VLPs elicited > 4 log10 anti-HPV16 L1 IgG titers without adjuvant, and aluminum hydroxide as adjuvant increased IgG titers 1.3- to 4-fold and reduced the anti-HPV16 L1 IgG2a / anti-HPV16 L1 IgG1 ratio value (use of aluminum hydroxide reduced the ratio of the IgG2a). Immunization with HPV16 L1 VLPs in combination with Freund's adjuvant enhanced IgG titers 5- to 12-fold. Seven-dose immunization markedly increased anti-HPV16 L1 IgM titers compared to four-dose immunization, as well as increasing the proportion of glycosylated antibodies. Our results suggest that antibody glycosylation can be controlled immunologically, and IgG and IgM profiles and glycosylation profiles of the vaccine-induced antibodies can be used as indicators reflecting the vaccine characteristics. These results indicate that the HPV16 L1 VLP dosing schedule can affect the quality of antigen-specific antibody responses. We suggest that dosing schedules should be noted in vaccination protocols for VLP-based vaccines.


Assuntos
Papillomavirus Humano 16/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Antivirais/imunologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Papillomavirus Humano 16/genética , Humanos , Esquemas de Imunização , Camundongos , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia
4.
Exp Appl Acarol ; 78(4): 555-564, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31367978

RESUMO

Blood-feeding ectoparasites constitute a growing burden for human and animal health, and animal production worldwide. In particular, mites (Acari: Gamasida) of the genera Dermanyssus (Dermanyssidae) and Ornithonyssus (Macronyssidae) infest birds and cause gamasoidosis in humans. The tropical fowl mite, Ornithonyssus bursa, is commonly found in tropical and subtropical countries but rarely reported in Europe. In this research we characterized the first two cases in Spain of clinical gamasoidosis diagnosed in patients infested with O. bursa, and investigated the IgE, IgM and IgG antibody response to mite proteins and the carbohydrate Galα1-3Galß1-(3)4GlcNAc-R (α-Gal) involved in the tick-bite associated alpha-Gal syndrome (AGS). The results suggested that O. bursa is establishing across Mediterranean countries, and may increase the risk for gamasoidosis. The immune antibody response to mite proteins was higher for IgM and similar for IgE and IgG antibodies between patients and non-allergic control individuals exposed to mite or tick bites. The anti-α-Gal antibody levels were similar between patients and controls, a result supported by the absence of this carbohydrate in mites. These results suggested that mite bites do not correlate with antibody response to acarine proteins or α-Gal, and are not associated with the AGS.


Assuntos
Proteínas de Artrópodes/imunologia , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/imunologia , Ácaros/fisiologia , Oligossacarídeos/imunologia , Idoso , Animais , Feminino , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Infestações por Ácaros/parasitologia , Ácaros/classificação , Espanha
5.
Mem Inst Oswaldo Cruz ; 114: e190145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291383

RESUMO

Anti-α-Gal responses may exert a protective effect in falciparum malaria. However, the biological role of such antibodies is still unknown during Plasmodium vivax infections. We investigated IgG and IgM responses to α-Gal in individuals with vivax malaria. Anti-α-Gal IgG and IgM levels were higher in these patients than in controls, but no significant correlation was found between parasitaemia and anti-α-Gal response, nor between this response and ABO blood group status. This is the first study to investigate anti-α-Gal antibodies in P. vivax-infected patients; a larger survey is necessary to achieve a better understanding of host immune response during vivax malaria.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Malária Vivax/sangue , Plasmodium vivax/imunologia , Adulto , Anticorpos Anti-Idiotípicos/metabolismo , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Malária Vivax/imunologia , Pessoa de Meia-Idade , Adulto Jovem
6.
BMC Public Health ; 19(1): 958, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319834

RESUMO

BACKGROUND: Dengue fever is the world's fastest spreading mosquito borne viral infection. It is prevalent throughout both subtropical and tropical region, and affects over 128 countries. Dengue virus (DENV) infection poses a serious global public health challenge to three billion people, resulting in approximately 200 million cases of morbidity and 50,000 cases of mortality annually. In Cameroon like in most sub-Saharan African countries, DENV infection occur concurrently with other infectious diseases whose symptoms often overlap, rendering differential diagnosis challenging. This study aims at determining the frequency of acute dengue among febrile children under 15 years attending hospitals in some areas of Cameroon. METHODS: A total of 961 children under the age of 15 were recruited in a cross-sectional study using systematic sampling technique and by selecting each subject out of the three. The study was conducted in 10 public health centers in Cameroon. Demographic data and risk factors of the subjects were obtained using well-structured questionnaires. Dengue virus NS1 antigen, IgM and IgG were analysed using a Tell me fast® Combo Dengue NS1-IgG/IgM Rapid Test. An in-house ELISA test for dengue specific IgM antibody was equally performed for confirmation. Descriptive statistical analysis was performed using Graph pad version 6.0. RESULTS: A prevalence of 6.14% acute dengue virus infection was observed among children with febrile illness with a significant difference (p = 0.0488) between males (4.7%) and females (7.7%). In addition, children who reportedly were unprotected from vectors, showed a comparatively higher prevalence of the disease seropositivity than those practicing protective measures. CONCLUSION: DENV infection therefore is an important cause of fever among children in Cameroon. Thus, there is a need to include differential screening for DENV infections as a tool in the management of fever in children in the country.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Vírus da Dengue , Dengue/epidemiologia , Febre/epidemiologia , Pediatria/estatística & dados numéricos , Adolescente , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Camarões/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Dengue/virologia , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/virologia , Humanos , Imunoglobulina M/análise , Imunoglobulina M/imunologia , Masculino , Prevalência , Fatores de Risco
7.
J Anim Sci ; 97(8): 3426-3439, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31233597

RESUMO

This study was conducted to investigate the effects of Clostridium butyricum addition to diets in late gestation and lactation on the reproductive performance and gut microbiota for sows. A total of 180 healthy Landrace × Yorkshire sows at 90 d of gestation were randomly assigned to one of four groups, with 45 replicates per group, receiving a basal commercial diet (Control, 0% C. butyricum) or diet added with 0.1% C. butyricum (1 × 108 CFU/kg of feed), 0.2% C. butyricum (2 × 108 CFU/kg of feed), 0.4% C. butyricum (4 × 108 CFU/kg of feed), respectively. The experiment was conducted from 90 d of gestation to weaning at 21 d of lactation. The results showed that the interval between piglet born was linearly (P < 0.05) decreased, and the duration of farrowing was significantly (quadratic, P < 0.05) shortened as C. butyricum addition increased. There was a linear (P < 0.05) increase in litter weight at weaning and litter weight gain. The concentrations of IgG and IgM in colostrum, and IgM in milk were linearly increased (P < 0.05) as C. butyricum addition. Serum MDA concentrations of sows at parturition and 14 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) decreased, respectively. The serum total antioxidant capacity concentrations of sows at parturition and 14 and 21 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) increased as C. butyricum addition, respectively. There was a linear decrease in the serum endotoxin concentration of sows on 21 d in lactation (P < 0.05). The serum cortisol concentrations of piglets at 14 and 21 d of age were both significantly (quadratic, P < 0.05) decreased. The 0.2% C. butyricum increased the relative abundance of Bacteroidetes (P = 0.016) at phylum level, Prevotellaceae_NK3B31_group, Prevotella_1, Prevotellaceae_UCG-003, Prevotella_9, Alloprevotella (P < 0.05) at genus level, and decreased the relative abundance of Proteobacteria, Gemmatimonadetes, Actinobacteria (P < 0.001) at phylum level, and Clostridium_sensu_stricto_1, Streptococcus, Escheruchia-Shigella, Sphingomonas, Succinivibrio (P < 0.05) at genus level and Firmicutes/Bacteroidetes ratio (P = 0.020). In conclusion, the present research indicated that dietary addition with C. butyricum could shorten the duration of farrowing and enhance the growth performance of suckling piglets. Moreover, 0.2% C. butyricum administration to sows changed the composition of intestinal microbiota, especially increased the relative abundance of Prevotella.


Assuntos
Ração Animal/análise , Clostridium butyricum/fisiologia , Microbioma Gastrointestinal , Reprodução , Suínos/microbiologia , Animais , Antioxidantes/análise , Colostro/imunologia , Dieta/veterinária , Feminino , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Intestinos/microbiologia , Lactação , Leite/imunologia , Parto , Gravidez , Suínos/imunologia , Desmame , Ganho de Peso/efeitos dos fármacos
8.
Biochemistry (Mosc) ; 84(6): 608-616, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31238860

RESUMO

The repertoire of antiglycan antibodies of peripheral blood was studied using a microarray containing 487 glycan antigens: fragments of mammalian glycans (N- and O-chains of glycoproteins, as well as glycolipids) and also bacterial polysaccharides. The sera samples correspond to the third, sixth, and twelfth months of life. The infants were divided into four groups according to their nutrition type: breast milk, standard formula, and partially or extensively hydrolyzed formula. During the first year of life, the total amount of IgG decreased; presumably, the lifetime of maternal IgG in the newborns' bloodstream is much greater than is generally assumed. At the same time, the IgM content was low during the first six months and increased significantly by the twelfth month. The antiglycan IgM repertoire of one-year-old infants was still different from that of their mothers, as well as from the repertoire of unrelated donors, in particular, by the absence of antibodies against the Galß1-3GlcNAc (LeC) disaccharide, which is found in almost all healthy humans. It is noteworthy that the level of IgM of breast-fed infants was significantly lower than that of formula-fed by the twelfth month.


Assuntos
Autoanticorpos/imunologia , Polissacarídeos/imunologia , Adulto , Autoanticorpos/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Lactente , Alimentos Infantis , Recém-Nascido , Mães
9.
Medicine (Baltimore) ; 98(23): e15724, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169672

RESUMO

Diagnosis of Q fever is difficult due to the lack of distinct clinical features that distinguish it from other febrile diseases. Serologic testing is the gold standard method for diagnosing Q fever, but antibody formation may not be detectable for 2 to 3 weeks from symptom onset, limiting early diagnosis. We thus evaluated the diagnostic utility of polymerase chain reaction (PCR) to detect Coxellia burnetii DNA in serum from patients with suspected acute Q fever.All adult patients with suspected acute Q fever were prospectively enrolled at a tertiary-care hospital from January 2016 through July 2018. Acute Q fever was diagnosed using clinical and laboratory criteria: fever with at least one other symptoms (myalgia, headache, pneumonia, or hepatitis) and single phase II immunoglobulin G (IgG) antibody titers ≥1:200 or immunoglobulin M (IgM) antibody titer ≥1:50 (probable), or a fourfold increase or seroconversion in phase II IgG antibody titers as measured by indirect immunofluorescence assays between paired samples (confirmed). We performed PCR targeting the transposase gene insertion element IS1111a of C. burnetii.Of the 35 patients with suspected acute Q fever, 16 (46%) were diagnosed with acute Q fever including 8 probable and 8 confirmed cases; the remaining 19 (54%) were diagnosed with other febrile diseases. The proportion of males diagnosed with Q fever was higher than those diagnosed with other febrile diseases (88% vs 44%, P = .03), but there were no other significant differences in clinical characteristics between the 2 groups. The Q fever PCR sensitivity was 81% (95% confidence interval [CI], 54-96), specificity was 90% (95% CI, 67-99), positive predictive value was 87% (95% CI, 63-96), and negative predictive value was 85% (95% CI, 67-94).Q fever PCR testing using blood from patients with suspected acute Q fever seems to be a rapid and useful test for early diagnosis of Q fever.


Assuntos
Coxiella burnetii/genética , DNA Bacteriano/sangue , Reação em Cadeia da Polimerase/estatística & dados numéricos , Febre Q/diagnóstico , Doença Aguda , Adulto , Anticorpos Antibacterianos/sangue , Coxiella burnetii/imunologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , República da Coreia , Sensibilidade e Especificidade
10.
Analyst ; 144(11): 3613-3619, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31070614

RESUMO

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic joint inflammation and one of the main causes of chronic disability worldwide with high prevalence in the ageing population. RA is characterized by autoantibody production, synovial inflammation and bone destruction, and the most accepted biomarker is rheumatoid factor (RF) autoantibodies. In this work, we developed a low-cost approach for the detection and quantification of the RF marker. This colorimetric immunosensor is based on gold nanoprobe crosslinking that results in extensive aggregation in the presence of the pentameric IgM RF. Aggregation of the nanoconjugates yields a color change from red to purple that can be easily observed by the naked eye. The interaction between nanoconjugates and the specific target was confirmed via dynamic light scattering (DLS), Raman spectroscopy and atomic force microscopy (AFM) imaging. This conceptual system shows a LOD of 4.15 UA mL-1 IgM RF (clinical threshold is set for 20 IU mL-1). The one-step biosensor strategy herein proposed is much faster than conventional detection techniques, without the need for secondary antibodies, additional complex washing or signal amplification protocols. To the best of our knowledge this is the first report on target induced aggregation of gold nanoprobes for quantitative colorimetric autoantibody detection.


Assuntos
Artrite Reumatoide/diagnóstico , Ouro/química , Imunoglobulina M/sangue , Nanopartículas Metálicas/química , Fator Reumatoide/sangue , Artrite Reumatoide/imunologia , Biomarcadores , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Humanos , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Limite de Detecção , Tamanho da Partícula , Fator Reumatoide/imunologia
11.
J Immunoassay Immunochem ; 40(4): 367-377, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31081465

RESUMO

The risk of exposure of slaughterhouse workers to Rift Valley fever (RVF) virus-infected animals in Nigeria was assessed by determining the prevalence of anti-RVF IgM in cattle, goats and sheep slaughtered in a major abattoir in Ibadan, Nigeria. Blood samples were collected from 290 animals in Bodija Municipal abattoir, Ibadan, Nigeria in January and February 2017 and analyzed for the presence of RVF virus using IgM Enzyme-Linked Immunosorbent Assay (ELISA) and Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) for detection of the virus RNA. Descriptive statistics was used to analyze data. Overall, an IgM prevalence of 0.7% (2/290) was found among the blood samples of the animals, suggesting recent exposure to the virus. Antibody was detected in the sera from a cow and one goat. RVF virus RNA was not detected in the 2 IgM positive blood samples. There was no statistically significant relationship between RVF IgM infection and some variables of the animals, including age, sex and breed (p ≥ 0.05). Results of this study indicate active RVF virus transmission in domestic livestock in Nigeria. The study emphasizes the need to embark on monitoring of human and animal populations to prevent outbreak of the virus in the country.


Assuntos
Febre do Vale de Rift/sangue , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática , Feminino , Cabras , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Nigéria , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Ovinos
12.
Fish Shellfish Immunol ; 91: 216-222, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31121288

RESUMO

In the present study, a monoclonal antibody (mAb) against large yellow croaker IgM was produced by immunizing mice with purified large yellow croaker serum IgM. Western blotting showed that this mAb could specifically react with the heavy chain of large yellow croaker serum IgM. Indirect immunofluorescence assay (IFA) analysis suggested that the resulting mouse anti-IgM mAb could recognize membrane-bound IgM (mIgM) molecules of large yellow croaker. This mouse anti-IgM mAb also can be used for sorting of large yellow croaker IgM+ B cells through the magnetic-activated cell sorting (MACS) method, which was further confirmed by RT-PCR analysis of specific marker genes for B cells. Flow cytometry analysis showed that the percentages of IgM+ B cells in head kidney, spleen and peripheral blood lymphocytes were 29.00 ±â€¯1.58%, 33.00 ±â€¯1.64%, and 16.50 ±â€¯2.39%, respectively. Additionally, the phagocytosis rates of IgM+ B cells for 0.5 µm beads in head kidney, spleen and peripheral blood were calculated to be 7.56 ±â€¯0.58%, 4.053 ±â€¯0.62% and 23.17 ±â€¯2.26%, respectively, while only 2.36 ±â€¯0.23%, 1.16 ±â€¯0.44% and 6.41 ±â€¯0.45 of IgM+ B cells in these three tissues ingested 1 µm beads. Taken together, our data demonstrated that the mouse anti-IgM mAb produced in this study could be used as a tool to characterize IgM+ B cells and to study functions of IgM in large yellow croaker.


Assuntos
Anticorpos Monoclonais/imunologia , Linfócitos B/imunologia , Imunoglobulina M/imunologia , Perciformes/imunologia , Animais , Western Blotting/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Camundongos , Camundongos Endogâmicos BALB C
13.
Pol J Microbiol ; 68(1): 51-57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050253

RESUMO

Non-specific and often misleading clinical presentation of active brucellosis has made it a diagnostic puzzle for treating physicians. Clinicians rely greatly on the detection of IgG and IgM anti-Brucella antibodies by ELISA. Different patterns of positivity have been observed for IgG and IgM anti-Brucella antibodies in different cases, which further increases the risk of an erroneous diagnosis. Detailed herein is our two-years data with varied Brucella serology patterns and their clinical interpretation. Between January 2015 to December 2017, 1102 samples were processed in the Immunology Laboratory of KFHU for Brucella serology. 68 samples were positive for both IgG and IgM, 28 samples were positive for IgG and negative for IgM while 15 samples were positive for IgM and negative for IgG antibodies against Brucella. Electronic medical records, history of exposure, signs, symptoms, laboratory data, and the final diagnosis were recorded for all these patients. None of the patients with only positive IgM antibodies was finally diagnosed with brucellosis, while a diagnosis of brucellosis was established for only one patient with IgG antibodies positive in his serum. All the double-positive (IgG- and IgM-positive) serology patterns were diagnosed as having brucellosis. We concluded that determination of single IgM or IgG anti-Brucella-antibodies by ELISA could both be considered as definite and should ideally be interpreted in the context of appropriate clinical scenario and confirmation by other laboratory assays.Non-specific and often misleading clinical presentation of active brucellosis has made it a diagnostic puzzle for treating physicians. Clinicians rely greatly on the detection of IgG and IgM anti-Brucella antibodies by ELISA. Different patterns of positivity have been observed for IgG and IgM anti-Brucella antibodies in different cases, which further increases the risk of an erroneous diagnosis. Detailed herein is our two-years data with varied Brucella serology patterns and their clinical interpretation. Between January 2015 to December 2017, 1102 samples were processed in the Immunology Laboratory of KFHU for Brucella serology. 68 samples were positive for both IgG and IgM, 28 samples were positive for IgG and negative for IgM while 15 samples were positive for IgM and negative for IgG antibodies against Brucella. Electronic medical records, history of exposure, signs, symptoms, laboratory data, and the final diagnosis were recorded for all these patients. None of the patients with only positive IgM antibodies was finally diagnosed with brucellosis, while a diagnosis of brucellosis was established for only one patient with IgG antibodies positive in his serum. All the double-positive (IgG- and IgM-positive) serology patterns were diagnosed as having brucellosis. We concluded that determination of single IgM or IgG anti-Brucella-antibodies by ELISA could both be considered as definite and should ideally be interpreted in the context of appropriate clinical scenario and confirmation by other laboratory assays.


Assuntos
Anticorpos Antibacterianos/sangue , Bacteriemia/diagnóstico , Brucella/imunologia , Brucelose/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Adolescente , Adulto , Anticorpos Antibacterianos/imunologia , Bacteriemia/microbiologia , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Arábia Saudita , Adulto Jovem
14.
Vet Immunol Immunopathol ; 211: 38-43, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084892

RESUMO

Natural antibodies (NAb) are antibodies that can bind to a particular antigen without any apparent antigenic stimulation. In this paper, a careful analysis has been carried out on NAb levels in goat kid serum; possible correlations with the total immunoglobulin (tot-Ig) levels and specific antibody (SpAb) response were considered. Twenty randomly chosen kids were submitted to a first blood sampling (day 0). After 60 and 100 days, new blood samplings were carried out in the same animals. On day 0, after blood collection, all animals were immunized with a commercial vaccine; the immunization was repeated 30 days apart. Some exogenous antigens were tested to verify their immunoreactivity to NAb. Among them, the synthetic hapten 2,4,6-trinitrophenyl (TNP) conjugated with bovine serum albumin, resulted as the antigen with the higher immunoreactivity to NAb. Tot-Ig levels increased over time (p < 0.001). On the contrary, NAb levels, both IgG- and IgM-isotypes, significantly decreased during the experimental period (p < 0.001 and <0.05, respectively). Linear regression analyses showed a high correlation between IgM-NAb and tot-IgM levels (p < 0.001) at all the evaluated sampling times. However, a significant correlation between IgG-NAb and IgM-NAb was found only at the 1st (p < 0.01) and at the 2nd sampling (p < 0.05). No significant correlations were found between SpAb response and the other assessed humoral immune parameters. The obtained results are discussed in the light of the possible use of NAb assessment for the evaluation of the immune system activity in goat.


Assuntos
Imunidade Adaptativa/imunologia , Anticorpos/imunologia , Cabras/imunologia , Imunoglobulinas/imunologia , Animais , Anticorpos/sangue , Formação de Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Cabras/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulinas/sangue , Masculino
15.
Molecules ; 24(9)2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31027344

RESUMO

The objective of this study was to identify novel acetylation (Ac) modifications of the C1-inhibitor (C1-INH) and explain the association of the levels of autoantibodies against acetylated C1-INH peptides with the risk of developing systemic lupus erythematosus (SLE). Ac modifications of the C1-INH were identified and validated through in-gel digestion, nano-liquid chromatography-tandem mass spectrometry, immunoprecipitation, and Western blotting by using serum protein samples obtained from patients with SLE and age-matched healthy controls (HCs). In addition, the levels of serum C1-INH, Ac-protein adducts, and autoantibodies against unmodified and acetylated C1-INH peptides were measured. C1-INH levels in patients with SLE were significantly lower than those in HCs by 1.53-fold (p = 0.0008); however, Ac-protein adduct concentrations in patients with SLE were significantly higher than those in HCs by 1.35-fold (p = 0.0009). Moreover, immunoglobulin M (IgM) anti-C1-INH367-385 Ac and IgA anti-C1-INH367-385 Ac levels in patients with SLE were significantly lower than those in HCs. The low levels of IgM anti-C1-INH367-385 (odds ratio [OR] = 4.725, p < 0.001), IgM anti-C1-INH367-385 Ac (OR = 4.089, p = 0.001), and IgA anti-C1-INH367-385 Ac (OR = 5.566, p < 0.001) indicated increased risks for the development of SLE compared with HCs.


Assuntos
Proteína Inibidora do Complemento C1/imunologia , Imunoglobulina A/imunologia , Imunoglobulina M/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Peptídeos/imunologia , Acetilação , Sequência de Aminoácidos , Autoanticorpos/imunologia , Autoantígenos/imunologia , Proteína Inibidora do Complemento C1/química , Proteína Inibidora do Complemento C1/metabolismo , Feminino , Humanos , Lúpus Eritematoso Sistêmico/sangue , Peso Molecular , Peptídeos/química , Ligação Proteica/imunologia , Curva ROC , Taiwan
16.
Int J Mol Sci ; 20(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013832

RESUMO

B cell superantigens, also called immunoglobulin superantigens, bind to the variable regions of either the heavy or light chain of immunoglobulins mirroring the lymphocyte-activating properties of classical T cell superantigens. Protein A of Staphylococcus aureus, protein L of Peptostreptococcus magnus, and gp120 of HIV are typical immunoglobulin superantigens. Mast cells are immune cells expressing the high-affinity receptor for IgE (FcεRI) and are strategically located in the human heart, where they play a role in several cardiometabolic diseases. Here, we investigated whether immunoglobulin superantigens induced the activation of human heart mast cells (HHMCs). Protein A induced the de novo synthesis of cysteinyl leukotriene C4 (LTC4) from HHMCs through the interaction with IgE VH3+ bound to FcεRI. Protein L stimulated the production of prostaglandin D2 (PGD2) from HHMCs through the interaction with κ light chains of IgE. HIV glycoprotein gp120 induced the release of preformed (histamine) and de novo synthesized mediators, such as cysteinyl leukotriene C4 (LTC4), angiogenic (VEGF-A), and lymphangiogenic (VEGF-C) factors by interacting with the VH3 region of IgE. Collectively, our data indicate that bacterial and viral immunoglobulin superantigens can interact with different regions of IgE bound to FcεRI to induce the release of proinflammatory, angiogenic, and lymphangiogenic factors from human cardiac mast cells.


Assuntos
Mastócitos/imunologia , Mastócitos/metabolismo , Miocárdio/imunologia , Miocárdio/metabolismo , Superantígenos/imunologia , Antígenos de Bactérias/imunologia , Antígenos Virais/imunologia , Biomarcadores , Liberação de Histamina , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/patologia
17.
Infect Immun ; 87(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30936154

RESUMO

Although nontypeable Haemophilus influenzae (NTHi) is a human-specific nasopharyngeal commensal bacterium, it also causes upper respiratory tract infections in children and lower respiratory tract infections in the elderly, resulting in frequent antibiotic use. The transition from symbiotic colonizing bacterium to opportunistic pathogen is not completely understood. Incorporation of sialic acids into lipooligosaccharides is thought to play an important role in bacterial virulence. It has been known for more than 25 years that sialic acids increase resistance to complement-mediated killing; however, the mechanism of action has not been elucidated thus far. Here, we provide evidence that growth of NTHi in the presence of sialic acids Neu5Ac and Neu5Gc decreases complement-mediated killing through abrogating the classical pathway of complement activation by preventing mainly IgM antibody binding to the bacterial surface. Therefore, strategies that interfere with uptake or incorporation of sialic acids into the lipooligosaccharide, such as novel antibiotics and vaccines, might be worth exploring to prevent or treat NTHi infections.


Assuntos
Proteínas do Sistema Complemento/imunologia , Infecções por Haemophilus/imunologia , Haemophilus influenzae/metabolismo , Imunoglobulina M/imunologia , Ácido N-Acetilneuramínico/metabolismo , Anticorpos Antibacterianos/imunologia , Transporte Biológico , Ativação do Complemento , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/genética , Haemophilus influenzae/crescimento & desenvolvimento , Haemophilus influenzae/imunologia , Humanos , Ácido N-Acetilneuramínico/imunologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-30961823

RESUMO

BACKGROUND: Brucellosis is the most common zoonotic diseases worldwide. The aim of this study was to develop and evaluate the diagnostic performance of an indirect-ELISA (I-ELISA) method based on whole cell Brucella abortus S99 lysates for detection of IgM anti-Brucella antibodies in a human serum. MATERIALS AND METHODS: The study was conducted in two species-rich endemic areas of Iran (Tehran and Lorestan provinces). Serum samples of 102 patients and 150 healthy individuals were tested by the new kit and the commercial Vircell kit for the presence of anti-Brucella IgM antibodies. The disease status was confirmed by Wright agglutination test. The difference in the mean optical densities (OD) recorded by the new and the Vircell kits for patients and healthy individuals were tested using Two-tailed Student t-test. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the new kit were informed using Receiver operating curve analysis. The results were used to guide the choice of cutoff. Agreements in ODs recorded by the new and the Vircell kit was visually inspected using Bland-Altman plot. RESULTS: The new I-ELISA showed excellent diagnostic performance (sensitivity and PPV = 95.7%, specificity and NPV = 97.8%) for the diagnosis of brucellosis. The cut-off area for the antibody index (AI) was determined to be 8-10, where AIs less than 8 and greater than 10 were considered Brucella-negative and -positive, respectively. AIs of 8-10 show equivocal results, requiring re-testing. The Vircell kit showed low (36.8%) sensitivity and perfect (100%) specificity on the same samples. The Bland-Altman plot showed low agreement between both tests in recording the OD values for the same individuals. CONCLUSION: The new I-ELISA based on whole cell Brucella abortus S99 showed a good performance for the detection of Brucella spp. Lack of agreement between the new and the Vircell kit suggest that the performance of ELISA kits might be dependent on the geographical area under study. Hence, validation of the new and the Vircell kits is recommended prior to their implementation in other geographical areas.


Assuntos
Anticorpos Antibacterianos/sangue , Brucella abortus/imunologia , Brucelose/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina M/sangue , Anticorpos Antibacterianos/imunologia , Brucelose/sangue , Feminino , Humanos , Imunoglobulina M/imunologia , Irã (Geográfico) , Masculino , Sensibilidade e Especificidade
19.
J Infect Chemother ; 25(6): 427-430, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30824301

RESUMO

Primary infection with Toxoplasma gondii (T. gondii) during pregnancy may cause congenital infection of the infant. This study evaluated whether screening using IgG avidity and multiplex-nested polymerase chain reaction (PCR) methods was effective for detecting a high-risk pregnancy for congenital T. gondii infection. In a prospective cohort study serum T. gondii IgG avidity was measured in 469 pregnant women who had a positive test for T. gondii antibody plus a positive or equivocal test for IgM. Multiplex-nested PCR for T. gondii DNA on amniotic fluid, maternal blood, and neonatal blood was performed with informed consent. Low (<30%), borderline (30-35%), and high (>35%) IgG avidity indices were found in 104 (22.2%), 30 (6.4%), and 305 (71.4%), respectively. A total of 12 cases had a positive PCR test for amniotic fluids of the prenatal amniocentesis or at birth, or neonatal blood. Seven of the 12 cases were diagnosed as having congenital T. gondii infection, and they had low IgG avidity indices. Congenital T. gondii infection screening using of IgG avidity and multiplex-nested PCR methods for pregnant women with a positive test for T. gondii antibody plus a positive or equivocal test for T. gondii IgM was useful for detecting a high-risk pregnancy and diagnosing congenital T. gondii infection.


Assuntos
Anticorpos Antiprotozoários/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Complicações Parasitárias na Gravidez/diagnóstico , Toxoplasma/isolamento & purificação , Toxoplasmose Congênita/diagnóstico , Adulto , Amniocentese , Líquido Amniótico/parasitologia , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antiprotozoários , Criança , Pré-Escolar , DNA de Protozoário/sangue , Feminino , Seguimentos , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulina M/isolamento & purificação , Lactente , Recém-Nascido , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/tratamento farmacológico , Complicações Parasitárias na Gravidez/parasitologia , Gravidez de Alto Risco , Estudos Prospectivos , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Congênita/sangue , Toxoplasmose Congênita/tratamento farmacológico , Toxoplasmose Congênita/parasitologia , Resultado do Tratamento
20.
BMC Infect Dis ; 19(1): 267, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885148

RESUMO

BACKGROUND: Rubella is a vaccine-preventable contagious disease causing an estimated 100,000 children to be born with congenital rubella syndrome each year globally. Studies documented that 18 rubella outbreaks were occurred each year in Ethiopia. Yeka sub-city woreda 13 public health emergency management office reported two measles suspected cases on 8 February, 2018. We investigated this outbreak to identify its etiology, describe the outbreak and implement control measures. METHODS: We described the outbreak using descriptive epidemiology. The study population was defined as students learning in the school where the outbreak occurred. Suspected rubella case was defined as student with generalized rash whereas confirmed case was suspected case tested positive for rubella IgM. Questionnaires, checklists and students record review were used to collect data. We searched for new cases in classes daily and excluded them from classes. The school environment was assessed and the outbreak was described in person and time. RESULTS: We identified 58 cases (median age: 4.6 years; IQR: 4-5 years) with six of them rubella IgM positive and 52 epidemiologically linked. The outbreak began on 8 February 2018 having multiple intermittent peaks during its course reaching its highest peak at 2 April, 2018 and ended on 20 April, 2018. Index cases were reported from two classes; however, cases were occurred in 13/15(86.67%) of the classes during the entire outbreak. Fifty five percent (32/58) and 45/58(77.59%) of the cases were females and 3-5 years children, respectively. Overall attack rate was 58/531(4.05%). Attack rate was higher in females 32/252 (12.7%) than in males 26/279 (9.32%), and higher 45/275(16.36%) in 3-5 years than those in 5-8 years 13/256(5.08%) children. Case fatality ratio was zero. All cases were vaccinated against measles but unvaccinated against rubella. CONCLUSIONS: Attack rate was higher in females than in males and higher in 3-5 years than 5-8 years children. We recommended establishing rubella surveillance system, conducting sero-prevalence of rubella among child bearing age females and establishing CRS surveillance among young infants to provide evidence-based information for RCV introduction. It was also recommended to develop a national rubella surveillance guideline which aid to exclude rubella cases from schools during outbreak.


Assuntos
Surtos de Doenças , Rubéola (Sarampo Alemão)/epidemiologia , Criança , Pré-Escolar , Etiópia/epidemiologia , Feminino , Humanos , Imunoglobulina M/imunologia , Incidência , Masculino , Prevalência , Rubéola (Sarampo Alemão)/imunologia , Vacina contra Rubéola , Instituições Acadêmicas , Estudantes , Inquéritos e Questionários
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