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1.
Ann Clin Lab Sci ; 51(4): 540-545, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34452893

RESUMO

OBJECTIVE: Mycoplasma pneumoniae (M. pneumoniae), an extracellular pathogen lacking a cell wall, causes respiratory infection in adults and children and has been implicated in asthma exacerbation; immunoglobulin (Ig) E may be involved in these exacerbations. Specific IgM and IgG immune response to M. pneumoniae has been reported, but less is known about IgE M. pneumoniae antibody (Ab) responses in asthma. Previous studies in our laboratory demonstrated that asthmatic children have increased IgM M. pneumoniae levels, but not IgE. Thus, we sought to investigate whether past M. pneumoniae infection triggers production of M. pneumoniae-specific IgE Abs in adult subjects with/without asthma. METHODS: M. pneumoniae- IgE and -IgM Ab responses were studied in adult asthmatic (N=22) and non-asthmatic (N=22) subjects (ELISA). Data are reported as antibody index. Threshold detection levels: IgE, IgM: 0.2, 0.9, respectively. RESULTS: M. pneumoniae-IgE Ab levels were low and below the threshold of detection in both asthmatic and non-asthmatics (0.002±0.008 vs. 0.02±0.03; P=0.021). However, specific-IgM levels were slightly higher in non-asthmatics compared with asthmatics (0.96±0.37 vs. 0.79±0.31; P=0.054). M. pneumoniae-IgM Ab positivity was similar in both groups (P=1.0). CONCLUSION: IgM M. pneumoniae Abs may play an important role in non-asthma and persist for months after acute infection. IgE M. pneumoniae Abs may play a less important role in both groups.


Assuntos
Anticorpos Antibacterianos/sangue , Asma/imunologia , Imunoglobulina E/imunologia , Imunoglobulina M/sangue , Mycoplasma pneumoniae/imunologia , Pneumonia por Mycoplasma/imunologia , Adulto , Anticorpos Antibacterianos/imunologia , Asma/sangue , Asma/complicações , Asma/epidemiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Pneumonia por Mycoplasma/sangue , Pneumonia por Mycoplasma/epidemiologia , Pneumonia por Mycoplasma/etiologia , Prognóstico
2.
BMC Infect Dis ; 21(1): 715, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330228

RESUMO

BACKGROUND: Haemophilus influenzae serotype b (Hib) conjugate vaccine was introduced in France in 1992 as a 3 + 1 scheme at 2, 3, and 4 months (primary vaccination) with a booster at the age of 16-18 months. The vaccination was simplified in 2013 to a 2 + 1 scheme at 2 and 4 months (primary immunization) and a booster at the age of 11 months. The coverage was 95.4% in France at 24 months in 2017. During the period 2017-2019 the number of Hib invasive infections increased with several cases of vaccine failure. METHODS: The numbers and proportions of Hib invasive isolates during the period 2017-2019 were compared and vaccine failure cases were explored. A seroprevalence study was performed by measuring anti-polyribosyl-ribitol phosphate (PRP) IgG concentrations by ELISA among children < 5 years of age at the time of sampling covering the periods of the 3 + 1 or 2 + 1 schemes of Hib vaccination. A collection of residual 232 sera was tested (group 3 + 1 n = 130) and (group 2 + 1, n = 102) was used. RESULTS: Anti-PRP IgG concentrations were significantly higher in toddlers of 2 years (median 2.9 µg/ml) in the 3 + 1 group while these concentrations showed a median of 0.58 µg/ml among children in 2 + 1 group. The proportion of children of 2 years of age who achieved 1 µg/ml threshold (56%) was higher in the 3 + 1 group than that observed in the 2 + 1 group (25%). All the detected cases of vaccine failure received the 2 + 1 scheme and anti-PRP IgG levels were less than 1 µg/ml at the admission. However, these levels increased significantly 1 month after the admission suggesting a secondary immune response to the Hib infection. CONCLUSIONS: The simplification of the vaccination to a 2 + 1 scheme seems to reduce the level of anti PRP IgG. Hib antibodies wane rapidly after the 11 months booster and may not be enough to ensure long term protection. Surveillance of cases and monitoring of titres need to be continued to inform future vaccination policy.


Assuntos
Infecções por Haemophilus/epidemiologia , Vacinas Anti-Haemophilus , Haemophilus influenzae tipo b/imunologia , Adulto , Anticorpos Antibacterianos/sangue , Pré-Escolar , França/epidemiologia , Infecções por Haemophilus/imunologia , Vacinas Anti-Haemophilus/administração & dosagem , Haemophilus influenzae tipo b/isolamento & purificação , Humanos , Esquemas de Imunização , Imunização Secundária , Memória Imunológica , Lactente , Polissacarídeos/imunologia , Estudos Soroepidemiológicos , Falha de Tratamento , Vacinação
3.
APMIS ; 129(9): 556-565, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34120372

RESUMO

The reported incidence of pertussis in European countries varies considerably. We aimed to study specific Bordetella pertussis seroprevalence in Europe by measuring serum IgG antibody levels to pertussis toxin (anti-PT IgG). Fourteen national laboratories participated in this study including Belgium, Denmark, Finland, Greece, Hungary, Italy, Lithuania, Malta, Norway, Poland, Portugal, Romania, Spain, and Sweden. Each country collected approximately 250 samples (N = 7903) from the age groups 20-29 years (N = 3976) and 30-39 years (N = 3927) during 2010-2013. Samples were anonymous residual sera from diagnostic laboratories and were analyzed at the national laboratories by a Swedish reference method, a commercial ELISA kit, or were sent to Sweden for analysis. The median anti-PT IgG concentrations ranged from 4 to 13.6 IU/mL. The proportion of samples with anti-PT IgG ≥100 IU/mL, indicating a recent infection ranged from 0.2% (Hungary) to 5.7% (Portugal). The highest proportion of sera with anti-PT IgG levels between 50 and <100 IU/mL, indicating an infection within the last few years, was found in Portugal (12.3%) and Italy (13.9%). This study shows that the circulation of B. pertussis is quite extensive in adults, aged 20-39 years, despite well-established vaccination programs in Europe.


Assuntos
Coqueluche/epidemiologia , Adulto , Anticorpos Antibacterianos/sangue , Bordetella pertussis/imunologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Imunoglobulina G/sangue , Incidência , Masculino , Estudos Soroepidemiológicos , Cobertura Vacinal/estatística & dados numéricos , Coqueluche/imunologia , Coqueluche/prevenção & controle , Adulto Jovem
4.
Eur J Clin Microbiol Infect Dis ; 40(9): 1983-1997, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34109500

RESUMO

SARS-CoV-2 antibody assays are used for epidemiological studies and for the assessment of vaccine responses in highly vulnerable patients. So far, data on cross-reactivity of SARS-CoV-2 antibody assays is limited. Here, we compared four enzyme-linked immunosorbent assays (ELISAs; Vircell SARS-CoV-2 IgM/IgA and IgG, Euroimmun SARS-CoV-2 IgA and IgG) for detection of anti-SARS-CoV-2 antibodies in 207 patients with COVID-19, 178 patients with serological evidence of different bacterial infections, 107 patients with confirmed viral respiratory disease, and 80 controls from the pre-COVID-19 era. In COVID-19 patients, the assays showed highest sensitivity in week 3 (Vircell-IgM/A and Euroimmun-IgA: 78.9% each) and after week 7 (Vircell-IgG: 97.9%; Euroimmun-IgG: 92.1%). The antibody indices were higher in patients with fatal disease. In general, IgM/IgA assays had only limited or no benefit over IgG assays. In patients with non-SARS-CoV-2 respiratory infections, IgG assays were more specific than IgM/IgA assays, and bacterial infections were associated with more false-positive results than viral infections. The specificities in bacterial and viral infections were 68.0 and 81.3% (Vircell-IgM/IgA), 84.8 and 96.3% (Euroimmun-IgA), 97.8 and 86.0% (Vircell-IgG), and 97.8 and 99.1% (Euroimmun-IgG), respectively. Sera from patients positive for antibodies against Mycoplasma pneumoniae, Chlamydia psittaci, and Legionella pneumophila yielded particularly high rates of unspecific false-positive results in the IgM/IgA assays, which was revealed by applying a highly specific flow-cytometric assay using HEK 293 T cells expressing the SARS-CoV-2 spike protein. Positive results obtained with anti-SARS-CoV-2 IgM/IgA ELISAs require careful interpretation, especially if there is evidence for prior bacterial respiratory infections.


Assuntos
Anticorpos Antivirais/sangue , Infecções Bacterianas/diagnóstico , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Infecções Respiratórias/diagnóstico , Anticorpos Antibacterianos/sangue , Infecções Bacterianas/sangue , COVID-19/sangue , COVID-19/virologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Infecções Respiratórias/sangue , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia
5.
J Zoo Wildl Med ; 52(2): 573-579, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130400

RESUMO

Coxiellosis, or Query (Q) fever, a disease caused by the intracellular bacteria Coxiella burnetii, was recently described in a managed breeding herd of white rhinoceros (Ceratotherium simum) in the southeastern United States. Clinical disease often results in abortion and could represent a conservation challenge for this species. In addition to the reproductive and herd management consequences, coxiellosis is also a zoonotic disease. Infection or clinical disease in any free-ranging rhinoceros species in a national park setting has not been previously described. In this study, evidence of prior infection was measured by immunofluorescent antibody titers in 89 serum samples collected from white rhinoceros within private reserves and a national park in South Africa. Total seropositivity was 48/89 (53.9% [95% CI, 43.6-63.9%]). Animals on private reserves had a seropositivity of 21/51 (41.1% [95% CI, 27.1-55.2%]), and national park rhinoceros had a higher rate of seropositivity at 71.0% [95% CI, 55.9-86.2%] (27/38; P= 0.004). Adults had a higher seropositivity compared with subadults (P= 0.03). There was no difference in seropositivity between sexes (P > 0.05). Results demonstrate that South African white rhinoceros populations are exposed to Coxiella, which could result in underrecognized reproductive consequences. Further studies should investigate potential implications for public health and conservation management of this species.


Assuntos
Anticorpos Antibacterianos/sangue , Coxiella burnetii/imunologia , Perissodáctilos/sangue , Febre Q/veterinária , Animais , Feminino , Masculino , Febre Q/sangue , Febre Q/epidemiologia , África do Sul/epidemiologia
6.
BMC Infect Dis ; 21(1): 581, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34134646

RESUMO

BACKGROUND: Despite high childhood immunization coverage, sporadic cases of diphtheria have been reported in Malaysia in recent years. This study aims to evaluate the seroprevalence of diphtheria among the Malaysian population. METHODS: A total of 3317 respondents age 2 years old to 60 years old were recruited in this study from August to November 2017. Enzyme-linked immunosorbent assay (ELISA) was used to measure the level of IgG antibody against the toxoid of C. diphtheriae in the blood samples of respondents. We classified respondent antibody levels based on WHO definition, as protective (≥0.1 IU/mL) and susceptible (< 0.1 IU/mL) to C. diphtheriae infection. RESULTS: Among the 3317 respondents, 57% were susceptible (38.1% of children and 65.4% of adults) and 43% (61.9% of children and 34.6% of adults) had protective antibody levels against diphtheria. The mean antibody level peaked among individuals aged 1-2 years old (0.59 IU/mL) and 6-7 years old (0.64 IU/mL) but generally decreased with age, falling below 0.1 IU/mL at around 4-6 years old and after age 20 years old. There was a significant association between age [Children: χ2 = 43.22(df = 2),p < 0.001)], gender [Adults: χ2 = 5.58(df = 1),p = 0.018] and ethnicity [Adults: χ2 = 21.49(df = 5),p = 0.001] with diphtheria toxoid IgG antibody level. CONCLUSIONS: About 57% of the Malaysian population have inadequate immunity against diphtheria infection. This is apparently due to waning immunity following childhood vaccination without repeated booster vaccination in adults. Children at age 5-6 years old are particularly vulnerable to diphtheria infection. The booster vaccination dose normally given at 7 years should be given earlier, and an additional booster dose is recommended for high-risk adults.


Assuntos
Anticorpos Antibacterianos/sangue , Toxoide Diftérico/imunologia , Difteria/epidemiologia , Imunoglobulina G/sangue , Adolescente , Adulto , Criança , Pré-Escolar , Corynebacterium diphtheriae/metabolismo , Difteria/patologia , Ensaio de Imunoadsorção Enzimática , Humanos , Lactente , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
7.
BMC Infect Dis ; 21(1): 521, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078297

RESUMO

BACKGROUND: The clinical manifestations of recent syphilis can be variable, with typical and atypical patterns. Several conditions may cause atypical clinical aspects, including human immunodeficiency virus (HIV) co-infection. Besides the clinical features, co-infections may completely alter syphilis serological tests, causing interpretative difficulties and diagnostic delays. Aim of the work is to describe the difficulties encountered during the diagnostic evaluation of atypical skin manifestations and of the serology for syphilis of an HIV-infected patient who had contracted it several times. CASE PRESENTATION: In 2020, a 52-year old HIV-positive bisexual male patient was admitted to our department with a 4-month history of moderately itchy cutaneous lesions localized at his neck, trunk and arms. In 2013, the patient presented with a classic syphilitic roseola of the trunk and a secondary syphilis was diagnosed, with increased levels of rapid plasma reagin (RPR), Treponema pallidum hemagglutination assay (TPHA), anti-Treponema pallidum IgM and IgG Index. A second episode occurred in 2018, as a primary syphilis with multiple ulcerative lesions of the penis, and increased levels of RPR, IgG and IgM. In 2019, a further episode of secondary syphilis was treated with Doxycycline. In 2020, erythematous and papular lesions with vesicular components and urticarial erythema multiforme (EM)-like lesions were present at the neck, trunk and arms. Serological tests and Nucleic Acid Amplification Test (NAAT) for Treponema Pallidum were performed, as well as a cutaneous biopsy with histological and immunohistochemical evaluation of one lesion. NAAT was negative for T. pallidum. Serological test results were discordant with a new syphilis infection, showing only increased levels of RPR and anti-Treponema IgG. The cutaneous biopsy revealed a non specific histological pattern, while the immunohistochemical evaluation with anti-spirochetal antibodies was mandatory for the diagnosis of recent syphilis, showing clusters of rod-shaped elements, some of which with spiral form, focally present at the epidermis and adnexal structures. CONCLUSIONS: Nowadays, syphilis may present with atypical clinical and serological features. Physicians should be aware of these possible alterations and consider syphilis even in case of uncommon clinical aspect and unclear serological tests. Cutaneous biopsy and immunohistochemical exam may be mandatory for the diagnosis.


Assuntos
Sífilis/diagnóstico , Treponema pallidum/isolamento & purificação , Anticorpos Antibacterianos/sangue , Biópsia , Infecções por HIV/complicações , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Recidiva , Minorias Sexuais e de Gênero , Sífilis/patologia , Sorodiagnóstico da Sífilis , Treponema pallidum/imunologia
8.
Fish Shellfish Immunol ; 116: 19-29, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34153428

RESUMO

Streptococcus agalactiae is one of the most important pathogens infecting tilapia worldwide and causes meningoencephalitis, septicemia and high mortalities with considerable losses. Various types of vaccines have been developed against S. agalactiae infection, such as inactivated vaccines, live attenuated vaccines and subunit vaccines. Bacterial ghosts (BGs) are nonliving, empty cell envelopes and have been reported as novel vaccine candidates. Therefore, the main aims of this study were to develop an S. agalactiae ghost vaccine (SAGV) and to evaluate the immune response and protective effect of SAGV against S. agalactiae with two novel adjuvants, Montanide™ ISA 763B VG and Montanide™ GEL02. Nile tilapia, mean weight 50 g, were divided into four groups as follows; 1) fish injected with PBS as control, 2) fish injected with the SAGV alone; 3) fish injected with the SAGV+Montanide™ ISA 763B VG; and 4) fish injected with SAGV+Montanide™ GEL02. Following vaccination, innate immunity parameters including serum lysozyme, myeloperoxidase, catalase, and bactericidal activity were all significantly enhanced. Moreover, specific serum IgM antibodies were induced and reached their highest level 2-8 weeks post vaccination. Importantly, the relative percent survival of tilapia vaccinated against the SAGV formulated with both adjuvants was 80-93%. Furthermore, the transcription of immune-related genes (IgM, TCRß, IL-1ß, IL-8 and TNFα) were up-regulated in tilapia after vaccination, indicating that both cellular and humoral immune responses were induced by these adjuvanted vaccines. In summary, Montanide™ ISA 763B VG and Montanide™ GEL02 can enhance immunoprotection induced by the SAGV vaccine against streptococcosis, demonstrating that both have value as potential adjuvants of fish vaccines.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Ciclídeos/imunologia , Doenças dos Peixes/prevenção & controle , Manitol/análogos & derivados , Manitol/administração & dosagem , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/administração & dosagem , Streptococcus agalactiae/imunologia , Animais , Anticorpos Antibacterianos/sangue , Catalase/sangue , Ciclídeos/sangue , Doenças dos Peixes/sangue , Doenças dos Peixes/imunologia , Proteínas de Peixes/sangue , Fígado/imunologia , Muramidase/sangue , Peroxidase/sangue , Baço/imunologia , Infecções Estreptocócicas/sangue , Infecções Estreptocócicas/imunologia
9.
Front Immunol ; 12: 632304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953709

RESUMO

Cross-reactive vaccines recognize common molecular patterns in pathogens and are able to confer broad spectrum protection against different infections. Antigens common to pathogenic bacteria that induce broad immune responses, such as the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of the genera Listeria, Mycobacterium, or Streptococcus, whose sequences present more than 95% homology at the N-terminal GAPDH1-22 peptide, are putative candidates for universal vaccines. Here, we explore vaccine formulations based on dendritic cells (DC) loaded with two molecular forms of Listeria monocytogenes GAPDH (LM-GAPDH), such as mRNA carriers or recombinant proteins, and compare them with the same molecular forms of three other antigens used in experimental vaccines, listeriolysin O of Listeria monocytogeness, Ag85A of Mycobacterium marinum, and pneumolysin of Streptococcus pneumoniae. DC loaded with LM-GAPDH recombinant proteins proved to be the safest and most immunogenic vaccine vectors, followed by mRNA encoding LM-GAPDH conjugated to lipid carriers. In addition, macrophages lacked sufficient safety as vaccines for all LM-GAPDH molecular forms. The ability of DC loaded with LM-GAPDH recombinant proteins to induce non-specific DC activation explains their adjuvant potency and their capacity to trigger strong CD4+ and CD8+ T cell responses explains their high immunogenicity. Moreover, their capacity to confer protection in vaccinated mice against challenges with L. monocytogenes, M. marinum, or S. pneumoniae validated their efficiency as cross-reactive vaccines. Cross-protection appears to involve the induction of high percentages of GAPDH1-22 specific CD4+ and CD8+ T cells stained for intracellular IFN-γ, and significant levels of peptide-specific antibodies in vaccinated mice. We concluded that DC vaccines loaded with L. monocytogenes GAPDH recombinant proteins are cross-reactive vaccines that seem to be valuable tools in adult vaccination against Listeria, Mycobacterium, and Streptococcus taxonomic groups.


Assuntos
Vacinas Bacterianas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Lipídeos/imunologia , Listeria/imunologia , Mycobacterium/imunologia , RNA Mensageiro/imunologia , Streptococcus/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Infecções Bacterianas/prevenção & controle , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteção Cruzada , Reações Cruzadas , Células Dendríticas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Interferon gama/imunologia , Lipídeos/química , Listeria/enzimologia , Listeria/genética , Camundongos , RNA Mensageiro/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
10.
PLoS Negl Trop Dis ; 15(5): e0009383, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34014927

RESUMO

BACKGROUND: Cholera is an acute, diarrheal disease caused by Vibrio cholerae O1 or 139 that is associated with a high global burden. METHODS: We analyzed the estimated duration of immunity following cholera infection from available published studies. We searched PubMed and Web of Science for studies of the long-term immunity following cholera infection. We identified 22 eligible studies and categorized them as either observational, challenge, or serological. RESULTS: We found strong evidence of protection at 3 years after infection in observational and challenge studies. However, serological studies show that elevated humoral markers of potential correlates of protection returned to baseline within 1 year. Additionally, a subclinical cholera infection may confer lower protection than a clinical one, as suggested by 3 studies that found that, albeit with small sample sizes, most participants with a subclinical infection from an initial challenge with cholera had a symptomatic infection when rechallenged with a homologous biotype. CONCLUSIONS: This review underscores the need to elucidate potential differences in the protection provided by clinical and subclinical cholera infections. Further, more studies are warranted to bridge the gap between the correlates of protection and cholera immunity. Understanding the duration of natural immunity to cholera can help guide control strategies and policy.


Assuntos
Anticorpos Antibacterianos/sangue , Cólera/prevenção & controle , Memória Imunológica/imunologia , Vibrio cholerae O139/imunologia , Vibrio cholerae O1/imunologia , Adolescente , Adulto , Anticorpos Antibacterianos/imunologia , Criança , Pré-Escolar , Cólera/imunologia , Toxina da Cólera/imunologia , Proteção Cruzada/imunologia , Humanos , Lactente , Lipopolissacarídeos/imunologia , Pessoa de Meia-Idade , Adulto Jovem
11.
Asia Pac J Public Health ; 33(5): 516-522, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018413

RESUMO

A cross-sectional survey was undertaken to estimate seroprevalence of immunoglobulin G antibodies against scrub typhus, spotted fever group rickettsiae, and typhus group rickettsiae in randomly selected 48 clusters in 12 districts of 3 Northeast states of India: Assam, Meghalaya, and Tripura. Individuals in 3 age groups (5-8, 9-17, and 18-45 years) were selected from each cluster. Sera (N = 2360) tested were collected as part of a national survey on dengue seroprevalence conducted between September 2017 and February 2018. Overall, seroprevalence of 2.5% was detected against rickettsioses, with highest positivity against spotted fever group rickettsiae, followed by scrub typhus and typhus group rickettsiae. Seroprevalence was highest in Tripura (3.7%), followed by Assam (2.6%) and Meghalaya (1.04%). Adults of 18 to 45 years of age were found to be most affected (3.8%). The study findings indicate the need for increasing testing facilities for active case detection at hospital levels. Efforts on implementing effective preventing strategies are suggested to be targeted in disease-specific endemic foci.


Assuntos
Anticorpos Antibacterianos , Infecções por Rickettsia , Rickettsia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Estudos Transversais , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Rickettsia/imunologia , Rickettsia/isolamento & purificação , Infecções por Rickettsia/epidemiologia , Estudos Soroepidemiológicos , Adulto Jovem
12.
Int J Infect Dis ; 108: 461-464, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34051363

RESUMO

BACKGROUND: Syphilis is endemic in the Sub-Saharan zone and disproportionately affects at-risk populations such as men who have sex with men, sex workers and HIV infected individuals. In this study, we measure the impact of syphilis among people living with HIV in the Republic of Chad, where no data are currently available. METHOD: Outpatients attending 2 HIV clinics in N'Djamena, Republic of Chad, were tested for syphilis. Subjects who tested positive for both non-treponemal (VDRL) and treponemal (TPHA) received a single dose of Benzathine Penicillin G, 2.4 MU. An additional VDRL test was performed 6 months after treatment to ensure appropriate serological response. RESULTS: Of 207 patients included, 29 (14%) tested positive for VDRL at the first visit, with moderate/low antibody titers (ranging from 1/2 to 1/8); 24 (82.6%) of these had treponemal immunization confirmed by TPHA test. Six months after Benzathine Penicillin treatment, 22/24 of the patients (91.6%) tested negative for VDRL, and 2 showed a 4-fold titer decline. CONCLUSION: This first study in the Republic of Chad suggests that syphilis infection is frequent among people living with HIV in this country. Systematic screening of syphilis should be considered in this population.


Assuntos
Antibacterianos/uso terapêutico , Infecções por HIV/complicações , Penicilina G Benzatina/uso terapêutico , Sífilis/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Antibacterianos/sangue , Chade/epidemiologia , Coinfecção , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Sífilis/diagnóstico , Sífilis/epidemiologia , Sífilis/imunologia , Adulto Jovem
13.
Mol Immunol ; 135: 276-284, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33940514

RESUMO

Type VI Secretion System (T6SS) contributes to both virulence and antimicrobial resistance in Acinetobacter baumannii. Valine-glycine repeat protein G (VgrG) is the core component of T6SS that exists in many bacterial pathogens that have emerged as a potent mediator of pathogenicity in A. baumannii. Two conserved sequences of vgrG 1263-2295 and vgrG1263-1608 were identified antigenic in various strains of Acinetobacter baumannii. The vgrg1263-1608 sequence was implanted in the Loopless C lobe (LCL) from N. meningitidis for surface display and exposure to functional epitopes. The VgrG and LCL-VgrG were expressed and purified. Groups of BALB/c mice were immunized with these proteins and challenged with A. baumannii. Specific IgG titers, whole-cell ELISA, animal survival rates in active and passive immunizations, the bacterial burden in mice tissues, and cytotoxicity of the proteins were determined. The specific IgG suppressed bacterial burdens in the organs, and increased survival rates were noted in the immunized mice. LCL-VgrG immunization provided better protection against A. baumannii infection than the VgrG immunization. The conserved region of VgrG is probably a safe immunogen to effective vaccine development or an antiserum to control A. baumannii infections.


Assuntos
Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/imunologia , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/imunologia , Oligopeptídeos/imunologia , Células A549 , Acinetobacter baumannii/patogenicidade , Animais , Anticorpos Antibacterianos/sangue , Carga Bacteriana/imunologia , Vacinas Bacterianas/administração & dosagem , Linhagem Celular , Feminino , Glicina/química , Humanos , Imunização , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/administração & dosagem , Sistemas de Secreção Tipo VI , Valina/química , Virulência/fisiologia
14.
Mol Immunol ; 135: 373-387, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34020083

RESUMO

Vibrio parahaemolyticus causes vibriosis in wide range of marine organisms, and is responsible for food borne illnesses in humans through consumption of contaminated uncooked/partially cooked seafood. Continued and widespread antibiotics usage to increase the productivity has led to antibiotics resistance development. This has necessitated the need to develop alternative methods to control its infection. Use of safe and effective vaccines against the virulence factors not only protects from infection, it also minimizes antibiotic usage. The colonization of V. parahaemolyticus in the host and disease development requires several adhesins present on the cell surface, and thereby make them attractive vaccine candidates. V. parahaemolyticus produces extracellular type 1 fimbriae that have been shown to play a role in adhesion, biofilm formation and virulence. FimH is one of the minor components of the type 1 fimbriae occurring on its very tip. Being present on the cell surface, it is highly immunogenic, and can be targeted as a potential vaccine candidate. The present study describes the immunogenic and vaccine potential of recombinant V. parahaemolyticus FimH (rVpFimH) expressed in E. coli. Immunization of BALB/c mice with the rVpFimH elicited a strong mixed immune response, T-cell memory (evidenced by antibody isotyping, cytokine profiling and T-cell proliferation assay), and agglutination positive antibodies. FACS analysis and immunogold labeling showed that the polyclonal anti-rVpFimH antibodies were able to recognize the FimH on V. parahaemolyticus cells. In vivo challenge of the rVpFimH-immunized mice with 2×LD50 dose of live bacteria showed one hundred percent survival. Thus, our findings clearly demonstrate the potential of FimH as an effective vaccine candidate against V. parahaemolyticus.


Assuntos
Adesinas Bacterianas/imunologia , Vacinas Bacterianas/imunologia , Proteínas de Fímbrias/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Vibrioses/prevenção & controle , Vibrio parahaemolyticus/imunologia , Adesinas Bacterianas/genética , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Biofilmes/crescimento & desenvolvimento , Modelos Animais de Doenças , Proteínas de Fímbrias/genética , Doenças Transmitidas por Alimentos/microbiologia , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Alimentos Crus/microbiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Alimentos Marinhos/microbiologia , Vibrioses/imunologia , Vibrio parahaemolyticus/genética , Virulência , Fatores de Virulência/genética , Fatores de Virulência/imunologia
15.
Res Vet Sci ; 137: 144-149, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33975193

RESUMO

Feline Vector-Borne Diseases show increased global prevalence and some Anaplasma and Ehrlichia species may pose a risk to human health. The diagnosis of Anaplasma and Ehrlichia species infection in cats is achieved by the combined use of different methods as cytologic examination evidencing intracytoplasmic morulae, serologic tests and molecular assays. The peripheral whole blood is considered the sample of choice for Anaplasma and Ehrlichia species DNA detection in cats, but false negative results are reported leading to underestimation of infection prevalence. In order to have a more accurate assessment of the spread of feline vector-borne pathogens, the presence of Anaplasma spp. and Ehrlichia spp. DNA in 37 owner and shelter cats subjected to necropsy were prospectively investigated by testing in end-point PCR spleen, bone marrow, blood clot and hair samples. The bacteria identified were genetically characterised. Three shelter cats tested positive for A. phagocytophilum DNA in spleen (one cat) or in hair samples (two cats). None of the cats tested positive in bone marrow and blood samples. From the results obtained, it can be assumed that the use of spleen or hair samples could allow a more reliable detection of A. phagocytophilum DNA in cats with blood tested negative. In the phylogeny constructed with a fragment of the heat shock (groEL) gene nucleotide sequences, all the identified A. phagocytophilum clustered with bacteria infecting a wide range of hosts, including humans, showing a potential zoonotic role.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Doenças do Gato/microbiologia , Ehrlichiose/veterinária , Cabelo/microbiologia , Baço/microbiologia , Doenças Transmitidas por Vetores/veterinária , Anaplasma phagocytophilum/imunologia , Animais , Anticorpos Antibacterianos/sangue , Gatos , DNA Bacteriano/isolamento & purificação , Feminino , Masculino , Técnicas de Diagnóstico Molecular/veterinária , Doenças Transmitidas por Vetores/diagnóstico , Doenças Transmitidas por Vetores/microbiologia
16.
Front Immunol ; 12: 592731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968011

RESUMO

Childhood vaccination plays critical role in protecting infants from several dreaded diseases. Of the global 15 million preterm (PT) infants with compromised immune system born annually, India contributes to >3.5 million. Generation of adequate vaccine-induced immune response needs to be ensured of their protection. Immune response of Indian PT (n = 113) and full-term (FT, n = 80) infants to pentavalent vaccine administered as per the national recommendation was studied. Antibody titers against component antigens of pentavalent vaccine, immune cells profiling (T and B cells, monocytes and dendritic cells) and plasma cytokines were determined pre- and post-vaccination. Additionally, cell-mediated recall immune responses to pentavalent antigens were evaluated after short time antigenic exposure to infant PBMCs. Irrespective of gestational age (GA), all the infants developed adequate antibody response against tetanus, diphtheria, and protective but lower antibody levels for Haemophilus influenzae type-b and hepatitis B in preterm infants. Lower (~74%) protective antibody response to pertussis was independent of gestational age. PT-infants exhibited lower frequencies of CD4 T cells/dendritic cells/monocytes, increased plasma IL-10 levels and lower proliferation of central and effector memory T cells than in term-infants. Proliferative central memory response of FT-infants without anti-pertussis antibodies suggests protection from subsequent infection. Responder/non-responder PT-infants lacked immunological memory and could be infected with Bordetella. For hepatitis B, the recall response was gestational age-dependent and antibody status-independent. Humoral/cellular immune responses of PT-infants were dependent on the type of the immunogen. Preterm infants born before 32 weeks of gestation may need an extra dose of pentavalent vaccine for long lived robust immune response.


Assuntos
Antígenos/imunologia , Idade Gestacional , Imunidade , Recém-Nascido Prematuro/imunologia , Vacinas Combinadas/imunologia , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Biomarcadores , Citocinas/sangue , Feminino , Humanos , Memória Imunológica , Imunofenotipagem , Índia/epidemiologia , Lactente , Recém-Nascido , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Vigilância em Saúde Pública , Vacinação
17.
J Immunol ; 206(10): 2402-2411, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33931485

RESUMO

Pneumococcal infections are common and serious complications of HIV-1 disease. Prevention has been compromised by the limited magnitude and quality of Ab responses to T cell-independent type 2 pneumococcal capsular polysaccharides (PPS). The pneumococcal polysaccharide-protein conjugate vaccine-13 (PCV-13) contains PPS conjugated to the T cell-dependent protein (diphtheria toxoid [DT] [CRM197]). We investigated the differential response to PPS and DT by human Ab-secreting B cells (ASC) after immunization with PCV-13 in newly diagnosed healthy HIV+ and control adults. The numbers of PPS-specific IgG ASC increased significantly and similarly in HIV+ and controls. However, DT-specific IgG ASC increased in controls but not HIV+ subjects. To determine the cellular basis of these disparate responses to DT and PPS, we characterized the frequency and activation of T follicular helper (Tfh) cells, the predominant T cell subset providing B cell help. Expression of inducible T cell costimulator (ICOS), which sustains Tfh function and phenotype, increased significantly among controls, when compared with the HIV+ group. Increases in ICOS+ Tfh correlated with changes in T-dependent, DT-specific IgG ASC in controls but not in HIV+ In contrast, ICOS expression did not correlate with T cell-independent type 2 PPS-specific ASC in either group. Of note, upon optimized ex vivo stimulation, CD4 T cells from HIV+ subjects differentiated into Tfh cells and formed synapses with Raji B cells at frequencies similar to that of controls. In summary, PCV-13-induced increase in ICOS expression on Tfh was associated with responses to DT, which was compromised in recently diagnosed healthy HIV+ adults and can be restored ex vivo by providing effective Tfh-differentiating signals.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Imunidade Adaptativa , HIV-1/imunologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Células T Auxiliares Foliculares/imunologia , Vacinação/métodos , Vacinas Conjugadas/imunologia , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Linfócitos B/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Imunogenicidade da Vacina , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/sangue , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Resultado do Tratamento , Adulto Jovem
18.
BMC Infect Dis ; 21(1): 407, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941094

RESUMO

BACKGROUND: The prevalent resurgence of pertussis has recently become a critical public health problem worldwide. To understand pertussis pathogenesis and the host response to both the pathogen and vaccines, a suitable pertussis animal model, particularly a non-human primate model, is necessary. Recently, a non-human primate pertussis model was successfully established with baboons. Rhesus macaques have been shown to be ideal animal models for several infectious diseases, but a model of infectious pertussis has not been established in these organisms. Studies on rhesus macaque models of pertussis were performed in the 1920s-1930s, but limited experimental details are available. Recent monkey pertussis models have not been successful because the typical clinical symptoms and transmission have not been achieved. METHODS: In the present study, infant rhesus macaques were challenged with Bordetella pertussis (B.p) using an aerosol method to evaluate the feasibility of this system as an animal model of pertussis. RESULTS: Upon aerosol infection, monkeys infected with the recently clinically isolated B.p strain 2016-CY-41 developed the typical whooping cough, leukocytosis, bacteria-positive nasopharyngeal wash (NPW), and interanimal transmission of pertussis. Both systemic and mucosal humoral responses were induced by B.p. CONCLUSION: These results demonstrate that a model of pertussis was successfully established in infant rhesus macaques. This model provides a valuable platform for research on pertussis pathogenesis and evaluation of vaccine candidates.


Assuntos
Macaca mulatta , Coqueluche/etiologia , Coqueluche/transmissão , Aerossóis/administração & dosagem , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Bordetella pertussis/imunologia , Bordetella pertussis/patogenicidade , Citocinas/sangue , Modelos Animais de Doenças , Leucocitose/microbiologia , Masculino , Nasofaringe/microbiologia
19.
BMC Infect Dis ; 21(1): 480, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039293

RESUMO

BACKGROUND: Hemoptysis is very common and can be life threatening in clinical practice for nontuberculous mycobacteria. The serum antibody against the Mycobacterium avium complex (MAC-Ab), the majority of nontuberculous mycobacteria species, is well known to reflect the activity of MAC lung disease; however, there is no study investigating the association between the MAC-Ab and hemoptysis in MAC patients. Therefore, we assessed whether the MAC-Ab is a good biomarker for hemoptysis among subjects with MAC lung disease. METHODS: This study was conducted as a five-year retrospective survey at the National Hospital Organization Fukuoka National Hospital. A total of 155 patients aged ≥20 years with MAC lung disease were enrolled and separated into seropositive and seronegative groups using the cutoff for MAC-Ab levels of 0.7 U/ml. The prevalence of hemoptysis and odds ratios for the presence of hemoptysis were estimated and compared between the groups. To investigate the linear trends in the relationship between MAC-Ab levels and hemoptysis, the subjects were classified into three groups using the tertile distribution of the MAC-Ab. RESULTS: The prevalence of hemoptysis was twice as high in the seropositive group than in the seronegative group (42.2 and 21.7%, respectively, P = 0.02). The multivariable-adjusted risk of hemoptysis was elevated in the seropositive group as compared with the seronegative group (odds ratio = 2.79 (95% confidence interval 1.15-7.44)). Likewise, when categorizing the subjects into three groups, the risk of hemoptysis increased with increasing MAC-Ab levels (P = 0.03 for trend). CONCLUSIONS: A positive MAC-Ab level was a significant risk factor for hemoptysis among patients with MAC lung disease. There were also positive trends in the association between the MAC-Ab titer and the likelihood of hemoptysis. Measuring the MAC-Ab may contribute not only to early detection of the risk of hemoptysis but also to early intervention with anti-NTM therapy and, as a result, to the prevention of hemoptysis in MAC patients.


Assuntos
Anticorpos Antibacterianos/sangue , Hemoptise/sangue , Complexo Mycobacterium avium/imunologia , Infecção por Mycobacterium avium-intracellulare/sangue , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Hemoptise/epidemiologia , Humanos , Masculino , Infecção por Mycobacterium avium-intracellulare/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco
20.
Nat Commun ; 12(1): 2871, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001895

RESUMO

Reported incidence of pertussis in the European Union (EU) and the European Economic Area (EEA) varies and may not reflect the real situation, while vaccine-induced protection against diphtheria and tetanus seems sufficient. We aimed to determine the seroprevalence of DTP antibodies in EU/EEA countries within the age groups of 40-49 and 50-59 years. Eighteen countries collected around 500 samples between 2015 and 2018 (N = 10,302) which were analysed for IgG-DTP specific antibodies. The proportion of sera with pertussis toxin antibody levels ≥100 IU/mL, indicative of recent exposure to pertussis was comparable for 13/18 countries, ranging between 2.7-5.8%. For diphtheria the proportion of sera lacking the protective level (<0.1 IU/mL) varied between 22.8-82.0%. For tetanus the protection was sufficient. Here, we report that the seroprevalence of pertussis in these age groups indicates circulation of B. pertussis across EU/EEA while the lack of vaccine-induced seroprotection against diphtheria is of concern and deserves further attention.


Assuntos
Difteria/epidemiologia , Tétano/epidemiologia , Coqueluche/epidemiologia , Adulto , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/imunologia , Bordetella pertussis/fisiologia , Difteria/imunologia , Difteria/prevenção & controle , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Europa (Continente)/epidemiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Tétano/imunologia , Tétano/prevenção & controle , Coqueluche/imunologia , Coqueluche/prevenção & controle
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