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1.
J Infect Dis ; 229(6): 1919-1925, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38451247

RESUMO

Current serologic tests for HIV screening and confirmation of infection present challenges to the adoption of HIV vaccines. The detection of vaccine-induced HIV-1 antibodies in the absence of HIV-1 infection, referred to as vaccine-induced seropositivity/seroreactivity, confounds the interpretation of test results, causing misclassification of HIV-1 status with potential affiliated stigmatization. For HIV vaccines to be widely adopted with high community confidence and uptake, tests are needed that are agnostic to the vaccination status of tested individuals (ie, positive only for true HIV-1 infection). Successful development and deployment of such tests will require HIV vaccine developers to work in concert with diagnostic developers. Such tests will need to match today's high-performance standards (accuracy, cost-effectiveness, simplicity) for use in vaccinated and unvaccinated populations, especially in low- and middle-income countries with high HIV burden. Herein, we discuss the challenges and strategies for developing modified serologic HIV tests for concurrent deployment with HIV vaccines.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/imunologia , Testes Sorológicos/métodos
2.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673779

RESUMO

Meningiomas are tumors of the central nervous system that vary in their presentation, ranging from benign and slow-growing to highly aggressive. The standard method for diagnosing and classifying meningiomas involves invasive surgery and can fail to provide accurate prognostic information. Liquid biopsy methods, which exploit circulating tumor biomarkers such as DNA, extracellular vesicles, micro-RNA, proteins, and more, offer a non-invasive and dynamic approach for tumor classification, prognostication, and evaluating treatment response. Currently, a clinically approved liquid biopsy test for meningiomas does not exist. This review provides a discussion of current research and the challenges of implementing liquid biopsy techniques for advancing meningioma patient care.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Biomarcadores Tumorais , Vesículas Extracelulares/metabolismo , Biópsia Líquida/métodos , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Meningioma/patologia , Prognóstico
3.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674927

RESUMO

Studies on tumor-associated antigens in brain tumors are sparse. There is scope for enhancing our understanding of molecular pathology, in order to improve on existing forms, and discover new forms, of treatment, which could be particularly relevant to immuno-oncological strategies. To elucidate immunological differences, and to provide another level of biological information, we performed antibody profiling, based on a high-density protein array (containing 8173 human transcripts), using IgG isolated from the sera of n = 12 preoperative and n = 16 postoperative glioblastomas, n = 26 preoperative and n = 29 postoperative meningiomas, and n = 27 healthy, cancer-free controls. Differentially reactive antigens were compared to gene expression data from an alternate public GBM data set from OncoDB, and were analyzed using the Reactome pathway browser. Protein array analysis identified approximately 350-800 differentially reactive antigens, and revealed different antigen profiles in the glioblastomas and meningiomas, with approximately 20-30%-similar and 10-15%-similar antigens in preoperative and postoperative sera, respectively. Seroreactivity did not correlate with OncoDB-derived gene expression. Antigens in the preoperative glioblastoma sera were enriched for signaling pathways, such as signaling by Rho-GTPases, COPI-mediated anterograde transport and vesicle-mediated transport, while the infectious disease, SRP-dependent membrane targeting cotranslational proteins were enriched in the meningiomas. The pre-vs. postoperative seroreactivity in the glioblastomas was enriched for antigens, e.g., platelet degranulation and metabolism of lipid pathways; in the meningiomas, the antigens were enriched in infectious diseases, metabolism of amino acids and derivatives, and cell cycle. Antibody profiling in both tumor entities elucidated several hundred antigens and characteristic signaling pathways that may provide new insights into molecular pathology and may be of interest for the development of new treatment strategies.


Assuntos
Glioblastoma , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/genética , Anticorpos , Antígenos de Neoplasias , Neoplasias Meníngeas/genética
4.
Molecules ; 27(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35209238

RESUMO

For the identification of antigenic protein biomarkers for rheumatoid arthritis (RA), we conducted IgG profiling on high density protein microarrays. Plasma IgG of 96 human samples (healthy controls, osteoarthritis, seropositive and seronegative RA, n = 24 each) and time-series plasma of a pristane-induced arthritis (PIA) rat model (n = 24 total) were probed on AIT's 16k protein microarray. To investigate the analogy of underlying disease pathways, differential reactivity analysis was conducted. A total of n = 602 differentially reactive antigens (DIRAGs) at a significance cutoff of p < 0.05 were identified between seropositive and seronegative RA for the human samples. Correlation with the clinical disease activity index revealed an inverse correlation of antibodies against self-proteins found in pathways relevant for antigen presentation and immune regulation. The PIA model showed n = 1291 significant DIRAGs within acute disease. Significant DIRAGs for (I) seropositive, (II) seronegative and (III) PIA were subjected to the Reactome pathway browser which also revealed pathways relevant for antigen presentation and immune regulation; of these, seven overlapping pathways had high significance. We therefore conclude that the PIA model reflects the biological similarities of the disease pathogenesis. Our data show that protein array analysis can elucidate biological differences and pathways relevant in disease as well be a useful additional layer of omics information.


Assuntos
Artrite Reumatoide/diagnóstico , Artrite Reumatoide/etiologia , Autoanticorpos/imunologia , Autoimunidade , Biomarcadores , Animais , Autoanticorpos/sangue , Autoantígenos/imunologia , Biologia Computacional/métodos , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Análise Serial de Proteínas , Ratos , Índice de Gravidade de Doença
5.
Trop Anim Health Prod ; 55(1): 23, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36547722

RESUMO

Bovine herpesvirus type 1 (BoHV 1) is a major bovine pathogen spreading worldwide and causing extensive damage to the livestock industry. BoHV causes respiratory, genital, and neurological disorders. A cross-sectional study was performed for the first time to estimate the seroreactivity to BoHV 1 and related risk factors among Iran's central desert dairy cattle. A total of 800 blood samples was randomly collected from 76 unvaccinated herds. Samples were tested with an indirect enzyme-linked immunosorbent assay (ELISA) commercial kit to detect BoHV 1 antibodies. The logistic regression model was used to analyze the data. BoHV 1 seroreactivity at animal and herd levels was 50% and 65%, respectively. Herd size was recognized as a risk factor (OR = 2.65, CI = 1.61-4.37) for seroreactivity to BoHV using GLM (p < 0.05). The high prevalence of BoHV 1 antibodies in the study area indicates the need to implement educational programs on the importance of the disease and design methods to control and prevent virus distribution.


Assuntos
Doenças dos Bovinos , Infecções por Herpesviridae , Herpesvirus Bovino 1 , Bovinos , Animais , Prevalência , Estudos Transversais , Irã (Geográfico)/epidemiologia , Anticorpos Antivirais , Fatores de Risco , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterinária
6.
Malar J ; 18(1): 273, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409360

RESUMO

BACKGROUND: Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP1) antigens play a critical role in host immune evasion. Serologic responses to these antigens have been associated with protection from clinical malaria, suggesting that antibodies to PfEMP1 antigens may contribute to natural immunity. The first N-terminal constitutive domain in a PfEMP1 is the Duffy binding-like alpha (DBL-α) domain, which contains a 300 to 400 base pair region unique to each particular protein (the DBL-α "tag"). This DBL-α tag has been used as a marker of PfEMP1 diversity and serologic responses in malaria-exposed populations. In this study, using sera from a malaria-endemic region, responses to DBL-α tags were compared to responses to the corresponding entire DBL-α domain (or "parent" domain) coupled with the succeeding cysteine-rich interdomain region (CIDR). METHODS: A protein microarray populated with DBL-α tags, the parent DBL-CIDR head structures, and downstream PfEMP1 protein fragments was probed with sera from Malian children (aged 1 to 6 years) and adults from the control arms of apical membrane antigen 1 (AMA1) vaccine clinical trials before and during a malaria transmission season. Serological responses to the DBL-α tag and the DBL-CIDR head structure were measured and compared in children and adults, and throughout the season. RESULTS: Malian serologic responses to a PfEMP1's DBL-α tag region did not correlate with seasonal malaria exposure, or with responses to the parent DBL-CIDR head structure in either children or adults. Parent DBL-CIDR head structures were better indicators of malaria exposure. CONCLUSIONS: Larger PfEMP1 domains may be better indicators of malaria exposure than short, variable PfEMP1 fragments such as DBL-α tags. PfEMP1 head structures that include conserved sequences appear particularly well suited for study as serologic predictors of malaria exposure.


Assuntos
Antígenos de Protozoários/imunologia , Malária Falciparum/imunologia , Plasmodium falciparum/fisiologia , Proteínas de Protozoários/imunologia , Adulto , Criança , Pré-Escolar , Sequência Conservada , Humanos , Lactente , Pessoa de Meia-Idade , Estrutura Terciária de Proteína , Adulto Jovem
7.
Am J Transplant ; 17(1): 161-172, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27251361

RESUMO

Kidney transplant donors are not currently implicated in predicting BK polyomavirus (BKPyV) infection in kidney transplant recipients. It has been postulated, however, that BKPyV infection originates from the kidney allograft. Because BKPyV seroreactivity correlates with BKPyV replication and thus might mirror the infectious load, we investigated whether BKPyV seroreactivity of the donor predicts viremia and BKPyV-associated nephropathy (BKPyVAN) in the recipient. In a retrospective cohort of 407 living kidney donor-recipient pairs, pretransplantation donor and recipient sera were tested for BKPyV IgG levels and correlated with the occurrence of recipient BKPyV viremia and BKPyVAN within 1 year after transplantation. Donor BKPyV IgG level was strongly associated with BKPyV viremia and BKPyVAN (p < 0.001), whereas recipient BKPyV seroreactivity showed a nonsignificant inverse trend. Pairing of high-BKPyV-seroreactive donors with low-seroreactive recipients resulted in a 10-fold increased risk of BKPyV viremia (hazard ratio 10.1, 95% CI 3.5-29.0, p < 0.001). In multivariate analysis, donor BKPyV seroreactivity was the strongest pretransplantation factor associated with viremia (p < 0.001) and BKPyVAN (p = 0.007). The proportional relationship between donor BKPyV seroreactivity and recipient infection suggests that donor BKPyV seroreactivity reflects the infectious load of the kidney allograft and calls for the use of pretransplantation BKPyV serological testing of (potential) donors and recipients.


Assuntos
Vírus BK/patogenicidade , Nefropatias/diagnóstico , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/imunologia , Infecções Tumorais por Vírus/imunologia , Viremia/diagnóstico , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Nefropatias/etiologia , Testes de Função Renal , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Infecções por Polyomavirus/sangue , Infecções por Polyomavirus/virologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Transplantados , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/virologia , Viremia/etiologia
8.
Biochim Biophys Acta Gen Subj ; 1861(2): 396-408, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27751956

RESUMO

BACKGROUND: We have characterized two immunogenic proteins, Rv1197 and Rv1198, of the Esx-5 system of the ESAT-6 family of Mycobacterium tuberculosis H37Rv. METHODS: The complex formation between Rv1197 and Rv1198 was characterized by biophysical techniques. The reactivity of serum from TB patients towards these proteins was characterized by ELISA. Lymphocyte proliferation and cytokine induction were followed in restimulated splenocytes from immunized mice by using MTT assay and CBA flowcytometry, respectively. RESULTS: Rv1197 and Rv1198 strongly interact to form a heterodimeric complex under reducing conditions, which is characterized by a dissociation constant of 97×10-9M and melting temperature, Tm, of 50.5°C. Strong humoral responses to Rv1197, Rv1198, CFP-10 and MoaC1 (Rv3111) antigens were found in Indian patients with active pulmonary tuberculosis (n=44), in comparison to non-infected healthy individuals (n=20). The seroreactivity to Rv1198 was characterized by a sensitivity of 75% and specificity of 90%. In BALB/c mice, immunization with Rv1198-FIA induced a pro-inflammatory response with elevated levels of TNF and IL-6, along with low induction of IFN-γ, IL-2 and IL-10, but no induction of IL-4. CONCLUSION: Rv1197 and Rv1198 form a stable complex, which is regulated by the redox state of Rv1198. Rv1198 is immunogenic with highly specific seroreactivity towards TB patients' serum. Rv1198 elicits a pro-inflammatory recall response in immunized mice. GENERAL SIGNIFICANCE: This study characterizes the interaction of Rv1197 and Rv1198, and establishes the immunogenic nature of Rv1198.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Mycobacterium tuberculosis/metabolismo , Adulto , Animais , Proliferação de Células/fisiologia , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Linfócitos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Tuberculose Pulmonar/microbiologia , Adulto Jovem
9.
Helicobacter ; 22(5)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28737284

RESUMO

BACKGROUND: Differences in Helicobacter pylori protein expression have been related to the risk of severe gastric diseases. In Spain, a marked geographic pattern in gastric cancer mortality has long been reported. OBJECTIVE: To characterize antibody reactivity patterns against 16 H. pylori proteins, by age, sex, and region of birth, in a large sample of the Spanish adult population. MATERIALS AND METHODS: Antibody reactivity was quantified by H. pylori multiplex serology in a sample from the control group of the multicase-control study MCC-Spain. For this analysis, 2555 population-based controls were included. Each participant was classified as seropositive or seronegative for each protein according to specific cutoffs. Overall H. pylori seroprevalence was defined as positivity against ≥4 proteins. Descriptive analyses by age, sex, and region of birth were performed for both seroprevalence and seroreactivity (continuous measure). Differences among groups were tested by logistic and linear regression models. RESULTS: Overall H. pylori seroprevalence increased with age in both sexes. For ages 55-74, seroprevalence was lower in women than in men (84% vs 92%, P<.001). Region of birth explained 7% of the variability in seroprevalence. Among H. pylori seropositive subjects, proteins with the highest seroprevalence were GroEL, NapA, HP231, and Omp. Seropositivity for most of the proteins increased or remained stable with age, rising mainly for CagA, GroEL, and HyuA in women. A clear cohort effect was not observed. CONCLUSIONS: This is the first study to describe the antibody patterns against 16 H. pylori proteins in the Spanish population. We found variability in the H. pylori antibody profiles according to both individual factors such as age and sex, and environmental factors such as the region of birth. The slightness of the reduction in seropositivity with decreasing age highlights the ongoing importance of this infection.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/imunologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Geografia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Espanha/epidemiologia
10.
Trop Anim Health Prod ; 49(2): 231-238, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27909915

RESUMO

Leptospirosis is a worldwide zoonosis which can affect many species. Control programs need accurate diagnosis to be successful, and currently, diagnosis relies on serology. It presents three main issues: the sampling, the antigen panel, and the cutoff point. Herein, we propose a systematic review on leptospirosis among dogs, pigs, and horses in Latin America in order to improve the understanding of the seroepidemiology of leptospirosis in these species in the region as well as the temporal development of the research on this topic and, consequently, improve the chances of success on control programs. Internet databases were consulted over 2015. Inclusion criteria included serosurvey using MAT; a relevant number of animals; the presence in the antigen panel of at least one representative of serogroups Icterohaemorrhagiae and Canicola for dogs, Icterohaemorrhagiae, Australis, and Pomona for pigs, and Icterohaemorrhagiae and Australis for horses; and a cutoff point of ≥100. Overall, 240 papers were studied, of which 87 referred to dogs, 66 to pigs, 39 to horses, and 48 to more than one of the studied species. In relation to those that met all the inclusion criteria, it was 45 (66.2%) in dogs, 23 (41.8%) in pigs, and 23 (63.9%) in horses. Leptospirosis is widespread in Latin America. Predominant serogroups are Canicola to dogs and Icterohaemorrhagiae to pigs and horses. Therefore, research on animal leptospirosis should be encouraged in Latin America, in order to reach a greater standardization in studies and then achieve better results on control programs.


Assuntos
Doenças do Cão/epidemiologia , Doenças dos Cavalos/epidemiologia , Leptospirose/veterinária , Doenças dos Suínos/epidemiologia , Animais , Doenças do Cão/microbiologia , Cães , Doenças dos Cavalos/microbiologia , Cavalos , América Latina/epidemiologia , Leptospira/fisiologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , Prevalência , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/microbiologia , Zoonoses/epidemiologia , Zoonoses/microbiologia
11.
Trop Anim Health Prod ; 48(2): 239-48, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26581437

RESUMO

The diagnosis of leptospirosis commonly relies on serology, which has three issues that are referred: the sampling, the antigen panel, and the cutoff point. We propose a systematic review of the bovine leptospirosis in Latin America, in order to provide a better understanding of the evolution of the research and of the seroepidemiology of bovine leptospirosis in that region. Internet databases were consulted over the year of 2014. Inclusion criteria for analysis included serosurvey using microscopic agglutination test (MAT), a relevant number of animals, the presence in the antigen panel of at least one representant of serogroup Sejroe, and a cutoff point of ≥100. A total of 242 articles that referred to cattle, leptospir*, and one region of Latin America was found. Only 105 articles regarding to serosurveys using MAT were found in several countries, and 61 (58.1 %) met all the inclusion criteria. In conclusion, this systematic review demonstrated a high prevalence of the infection (75.0 % at herd level and 44.2 % at animal level), with predominance of strains of serogroup Sejroe (80.3 %). It was evident that there is the necessity of more studies in several countries, as well as the need for greater standardization in studies, especially with regard to the adopted cutoff point at serological tests.


Assuntos
Doenças dos Bovinos/epidemiologia , Leptospirose/veterinária , Testes de Aglutinação/veterinária , Animais , Antígenos de Bactérias/imunologia , Bovinos , Doenças dos Bovinos/diagnóstico , Leptospira/imunologia , Prevalência , Estudos Soroepidemiológicos , Testes Sorológicos/veterinária , América do Sul/epidemiologia
12.
Med Mycol ; 53(6): 576-86, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26026172

RESUMO

Cryptococcus neoformans is an opportunistic fungal pathogen that causes lung inflammation and meningoencephalitis in immunocompromised patients but is also able to asymptomatically infect immunocompetent individuals. C. neoformans is found ubiquitously especially in urban areas where it is spread by pigeons, and fungal exposure may predispose for asthma development already at an early age, as soon as confronted with pigeon droppings. In the study presented here, we investigated the presence of specific immunoglobulin G (IgG) against C. neoformans in sera from patients suffering from asthma in comparison to a healthy control cohort, accrued from the Leipzig Research Centre for Civilization Diseases (LIFE). For serological analysis we developed a flow cytometry (FACS) based assay specific for an acapsular strain of C. neoformans to comprehensively analyze different cryptococcal serotypes. Compared with the non-asthmatic cohort, asthmatics exhibited, as expected, an elevated level of total serum immunoglobulin E (IgE), whereas the IgG seroreactivity against C. neoformans was not significantly different among the two groups (P = .118). Nevertheless, there was a trend toward increased Cryptococcus-specific IgG antibodies in the serum of asthmatics. Additionally, in male asthmatics an increased IgG-mediated seroreactivity compared to female asthmatics was found. This points to a higher prevalence of subclinical C. neoformans infection in male asthmatics and may support the hypothesis of C. neoformans as a risk factor for the development of asthma in urban areas.


Assuntos
Anticorpos Antifúngicos/sangue , Asma/epidemiologia , Criptococose/imunologia , Cryptococcus neoformans/imunologia , Adulto , Asma/complicações , Estudos de Casos e Controles , Criptococose/complicações , Criptococose/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Emerg Infect Dis ; 20(7): 1183-90, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24960072

RESUMO

Borrelia miyamotoi sensu lato, a relapsing fever Borrelia sp., is transmitted by the same ticks that transmit B. burgdorferi (the Lyme disease pathogen) and occurs in all Lyme disease-endemic areas of the United States. To determine the seroprevalence of IgG against B. miyamotoi sensu lato in the northeastern United States and assess whether serum from B. miyamotoi sensu lato-infected persons is reactive to B. burgdorferi antigens, we tested archived serum samples from area residents during 1991-2012. Of 639 samples from healthy persons, 25 were positive for B. miyamotoi sensu lato and 60 for B. burgdorferi. Samples from ≈10% of B. miyamotoi sensu lato-seropositive persons without a recent history of Lyme disease were seropositive for B. burgdorferi. Our results suggest that human B. miyamotoi sensu lato infection may be common in southern New England and that B. burgdorferi antibody testing is not an effective surrogate for detecting B. miyamotoi sensu lato infection.


Assuntos
Infecções por Borrelia/epidemiologia , Borrelia/imunologia , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Infecções por Borrelia/sangue , Infecções por Borrelia/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Doença de Lyme/sangue , Doença de Lyme/epidemiologia , Doença de Lyme/imunologia , Masculino , Pessoa de Meia-Idade , New England/epidemiologia , Estudos Soroepidemiológicos
14.
J Infect Dis ; 208(9): 1514-9, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23901079

RESUMO

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens mediate parasite sequestration and host immune evasion. Reactivity to 21 PfEMP1 fragments on a protein microarray was measured in serum samples from Malian children aged 1-6 years and adults. Seroreactivity to PfEMP1 fragments was higher in adults than in children; intracellular conserved fragments were more widely recognized than were extracellular hypervariable fragments. Over a malaria season, children maintained this differential seroreactivity and recognized additional intracellular PfEMP1 fragments. This approach has the potential to identify conserved, seroreactive extracellular PfEMP1 domains critical for protective immunity to malaria.


Assuntos
Antígenos de Protozoários/imunologia , Malária Falciparum/imunologia , Fragmentos de Peptídeos/imunologia , Proteínas de Protozoários/imunologia , Adulto , Anticorpos Antiprotozoários/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Lactente , Malária Falciparum/sangue , Plasmodium falciparum/imunologia , Análise Serial de Proteínas , Estrutura Terciária de Proteína
15.
Vet Parasitol ; 329: 110197, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735268

RESUMO

We tested the hypothesis that age, breed, and sex are related to hematology, biochemistry, acute phase proteins (APPs), seroreactivity and level of parasitemia in dogs with an acute phase response (APR) due to Babesia canis infection. The study enrolled 61 privately owned dogs that naturally acquired B. canis infection. Groups were formed according to the age: young dogs less than one year, and adult dogs more than one year old. Moreover, the group of males was compared to females and purebred to mixed breed dogs. Seroreactivity was tested with immunofluorescence antibody test, level of parasitemia with real-time polymerase chain reaction (real-time PCR), hematology, and biochemistry with automatic analyzers, serum amyloid A with enzyme-linked immunosorbent assay, fibrinogen with heat precipitation and ceruloplasmin and paraoxonase-1 with manual spectrophotometric methods. For protein separation agarose gel electrophoresis was used. The main changes in the whole population of B. canis-infected dogs were fever, pancytopenia, and change in APPs level. One-third of young, and 96% of adult dogs were seropositive (P < 0.001). The level of parasitemia was higher in the young dogs (P < 0.001). Erythroid lineage parameters (P < 0.01), and leukocytes (P < 0.05) were lower in the young, when compared to the adult dogs. Young dogs had lower total globulins (P < 0.001), ß- and γ-globulins (P < 0.001), and higher α-globulins (P = 0.022) than adult dogs. Young dogs had higher concentrations of phosphate (P = 0.003) and cholesterol (P < 0.001) and lower amylase (P = 0.014) and lipase activity (P = 0.020) than adult ones. Male dogs had lower neutrophil count than females (P = 0.035), and purebred dogs had more band neutrophils than mixed breed dogs (P = 0.004). In conclusion, dogs with natural Babesia canis infection at a young age have more severe anemia and APR including leukopenia than adults. Male and purebred dogs might also have more severe APR than females and mix-breeds, as they have more pronounced changes related to the myeloid lineage.


Assuntos
Babesia , Babesiose , Doenças do Cão , Cães , Animais , Babesiose/parasitologia , Babesiose/sangue , Doenças do Cão/parasitologia , Feminino , Masculino , Babesia/genética , Fatores Sexuais , Fatores Etários , Parasitemia/veterinária , Anticorpos Antiprotozoários/sangue
16.
Microbiol Spectr ; 11(3): e0071523, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37222611

RESUMO

Vaccine-induced seroreactivity/positivity (VISR/P) poses a significant and common challenge to HIV vaccine implementation, as up to 95% of vaccine recipients may be misclassified as having HIV infection by current HIV screening and confirmatory serological assays. We investigated whether internal HIV proteins could be used to overcome VISR and discovered a set of 4 antigens (gp41 endodomain, p31 integrase, p17 matrix protein, and Nef) that are recognized by antibodies produced in individuals with HIV infection but not in vaccinated individuals. When evaluated in a multiplex double-antigen bridging ELISA, this antigen combination had specificities of 98.1% prevaccination and 97.1% postvaccination, demonstrating the assay is minimally impacted by vaccine-induced antibodies. The sensitivity was 98.5%, further increasing to 99.7% when p24 antigen testing was included. Results were similar across HIV-1 clades. Although more technical advancements will be desired, this research provides the groundwork for the development of new fourth-generation HIV tests unaffected by VISR. IMPORTANCE While the detection of HIV infection is accomplished by several methods, the most common are serological tests that detect host antibodies produced in response to viral infection. However, the use of current serological tests may present a significant challenge to the adoption of an HIV vaccine in the future because the antibodies to HIV antigens detected in currently available tests also tend to be included as antigens in the HIV vaccines in development. The use of these serological tests may thus result in the misclassification of vaccinated HIV-negative individuals, which can have potential for significant harms for individuals and could prevent the widespread adoption and implementation of HIV vaccines. Our study aimed to identify and evaluate target antigens for inclusion in new serological tests that can be used to identify HIV infections without interference from vaccine-induced antibodies but also fit within existing platforms for HIV diagnostics.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Infecções por HIV/diagnóstico , Anticorpos Antivirais , Testes Sorológicos/métodos
17.
Clin Microbiol Infect ; 29(12): 1561-1566, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769899

RESUMO

OBJECTIVES: Lyme borreliosis (LB) is the most common tick-transmitted infection in the northern hemisphere and is caused by bacteria in the Borrelia burgdorferi sensu lato (Bbsl)-complex. The diagnosis is partially based on serology, and clinicians often take follow-up serum samples to look for seroconversion or an increase in IgG-antibody levels. In this registry-based study, we proposed a method for determining actual changes in IgG and examined antibody reactivity and decay. METHODS: Serological data from the departments of clinical microbiology at Karlstad Hospital, Sweden, and Slagelse Hospital, Denmark, were used to calculate a seroreactivity cut-off (SCOFF), above which changes between two samples from the patient cannot be explained by random variation. Increases in IgG reactivity as well as IgG and IgM decay were illustrated using time-to-event analysis and the SCOFF. RESULTS: A total of 44,861 serum samples from 34,157 patients were tested for Bbsl-antibodies. Of the 4301 patients with follow-up samples taken within 100 days, 201 (4.67%) were above the SCOFF of 1.42 with a median time to follow-up sample of 36 days (interquartile range: 21). IgG demonstrated longer median time for all antibody levels (indeterminate: 4.6 years, low: 7.0 years, moderate-high: 8.8 years) than IgM antibodies (indeterminate: 2.1 years, low: 3.9 years, moderate-high: 6.8 years) and higher initial antibody levels persisted significantly longer for both IgG and IgM antibodies (p < 0.001). Of the 7868 patients with follow-up samples, isolated IgM reactivity preceded an increase in IgG reactivity in 18 patients (0.23%). DISCUSSION: The SCOFF indicated little biological and random variation for Bbsl-specific IgG antibodies on the platforms used during the study. In most follow-up samples, both IgG and IgM antibodies persisted for years, with longer seropositivity associated with high initial antibody levels and IgG-type antibodies. The diagnostic value of isolated IgM reactivity was limited.


Assuntos
Grupo Borrelia Burgdorferi , Borrelia burgdorferi , Doença de Lyme , Humanos , Suécia/epidemiologia , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , Anticorpos Antibacterianos , Imunoglobulina G , Imunoglobulina M , Dinamarca/epidemiologia
18.
J Vet Intern Med ; 36(1): 116-125, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34788481

RESUMO

BACKGROUND: Improved understanding of Bartonella spp. serology in dogs may aid clinical decision making. OBJECTIVE: Describe demographic and geographic patterns of Bartonella spp. seroreactivity in dogs, and describe hematologic and serum biochemical abnormalities in Bartonella spp. seroreactive and nonseroreactive dogs. ANIMALS: Serum samples from 5957 dogs in the United States, previously submitted to IDEXX Reference Laboratories. METHODS: Serum was tested using 3 indirect ELISAs for B. henselae, B. vinsonii subsp. berkhoffii, and B. koehlerae. Complete blood count and serum biochemistry panel results were reviewed retrospectively. RESULTS: Overall, 6.1% of dogs were Bartonella spp. seroreactive. Toy breeds were less likely to be seroreactive (3.9%) than mixed breeds (7.5%; adjusted odds ratio [aOR], 0.48; 95% confidence interval [CI], 0.32-0.72), and dogs <1 year old were less likely to be seroreactive (3.4%) than dogs 1 to 5.5 years of age (7.3%; aOR, 0.42; 95% CI, 0.23-0.72). Dogs in the West South Central (9.8%) and South Atlantic (8.8%) regions were more likely than dogs elsewhere in the United States to be seroreactive (aOR, 2.22; 95% CI, 1.31-3.87; aOR, 2.44; 95% CI, 1.38-4.36). CONCLUSIONS AND CLINICAL IMPORTANCE: Demographic and geographic findings for Bartonella spp. exposure were broadly comparable to previously reported patterns.


Assuntos
Infecções por Bartonella , Bartonella , Doenças do Cão , Animais , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/veterinária , Doenças do Cão/epidemiologia , Cães , Estudos Retrospectivos , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia
19.
Pathogens ; 11(9)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36145472

RESUMO

Canine leptospirosis is a zoonosis of epidemiological importance. Dogs are recognized as primary reservoirs of Leptospira interrogans serogroup Canicola and a source of infection to the environment through urine. This study aimed to determine the presence of antibodies against Leptospira in canines from 49 municipalities in the Department of Antioquia, Colombia. We performed a cross-sectional study of dogs included in a neutering control program. We collected 1335 sera samples, assayed by a microagglutination test (MAT), and performed PCR detection in 21 urine samples. We also surveyed 903 dog owners. We found a seroreactivity of 11.2% (150/1335) in Antioquia with titers ≥1:50. Municipalities with the highest number of cases were Belmira (46.1%), Turbo (34.5%), and Concepción (31.0%). L. santarosai was identified by phylogenetic analysis in one urine sample from the municipality of Granada. The most important factor associated with a positive result was the lack of vaccination against leptospirosis (PR 3.3, p ≤ 0.014). Environmental factors such as water presence and bare soil around the household were also associated with Leptospira seroreactivity in the Department of Antioquia. We reviewed a national epidemiological surveillance database for human cases in those municipalities. We found a correlation between the high number of cases in canines and humans, especially in the Uraba. Serological and molecular results showed the circulation of Leptospira. Future public health efforts in the municipalities with the highest numbers of seroreactivity should be directed towards vaccination to prevent animal disease and decrease the probability of transmission of Leptospira. Dogs actively participate in the Leptospira cycle in Antioquia and encourage the implementation of vaccination protocols and coverage.

20.
Pathogens ; 11(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35335695

RESUMO

The tick-borne encephalitis virus (TBEV) causes a life-threatening disease named Tick-borne encephalitis (TBE). The clinical symptoms associated with TBE range from non-specific to severe inflammation of the central nervous system and are very similar to the clinical presentation of other viral meningitis/encephalitis. In consequence, TBE is often misclassified by clinical physicians, mainly in the non-identified high-risk areas where none or only a few TBE cases have been reported. Considering this situation, we hypothesized that among persons from northern Serbia who recovered from viral meningitis or encephalitis, there would be evidence of TBEV infection. To test this hypothesis, in this observational study, we evaluated the seroreactivity against TBEV antigens in patients from northern Serbia who were hospitalized due to viral meningitis and/or viral encephalitis of unknown etiology. Three cases of seroreactivity to TBEV antigens were discovered among convalescent patients who recovered from viral meningitis and/or encephalitis and accepted to participate in the study (n = 15). The clinical and laboratory findings of these patients overlap with that of seronegative convalescent patients. Although TBE has been a notifiable disease in Serbia since 2004, there is no active TBE surveillance program for the serologic or molecular screening of TBEV infection in humans in the country. This study highlights the necessity to increase the awareness of TBE among physicians and perform active and systematic screening of TBEV antibodies among patients with viral meningitis and/or encephalitis.

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