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2.
PLoS One ; 19(2): e0298912, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38394120

RESUMO

BACKGROUND: Mozambique is a high-prevalence country for HIV and early detection of new HIV infections is crucial for control of the epidemic. We aimed to evaluate the accuracy of the 4th-generation rapid diagnostic test (RDT) AlereTM HIV Combo in detecting acute and seroconverted HIV-infection, among sexually-active women attending three clinical health centers in Maputo, Mozambique. METHODS: Women aged 14-55 years (n = 920) seeking care at the Mavalane Health Area, Maputo (February 2018-January 2019) were included, and blood specimens sampled. Sociodemographic and sexual behavior data were collected. Point-of-care HIV testing was performed using Alere DetermineTM HIV-1/2 and Uni-GoldTM HIV-1/2. All samples were also tested using Enzygnost® HIV Integral 4 and Innotest® HIV Antigen mAb in laboratory. The 4th-generation RDT AlereTM HIV Combo was evaluated on serum samples in the laboratory. Finally, Innotest® HIV Antigen mAb, Enzygnost® HIV Integral 4 (Ag/Ab), and HIV RNA quantification acted as gold standard assays in the evaluation of AlereTM HIV Combo test for HIV antigen detection (in clinical samples and in three HIV-1 seroconversion panels). RESULTS: The antibody component of the 4th generation AlereTM HIV Combo RDT demonstrated a sensitivity and specificity of 100% examining clinical samples. However, the test did not detect HIV p24 antigen in any clinical samples, while Innotest® HIV Antigen mAb, verified by Enzygnost® HIV Integral 4 (Ag/Ab) and/or HIV RNA quantification, detected HIV antigen in six clinical samples. Furthermore, the AlereTM HIV Combo RDT had a low sensitivity in the detection of HIV p24 antigen in seroconversion panels. The HIV prevalence among the examined women was 17.8%. CONCLUSIONS: The 4th-generation RDT AlereTM HIV Combo showed similar sensitivity to the 3rd-generation RDTs to detect seroconverted HIV-infections. However, the sensitivity for detection of HIV p24 antigen and diagnosing acute HIV infections, before seroconversion, was low. There is an urgent need to develop and evaluate simple and affordable POC tests with high sensitivity and specificity for diagnosing individuals with acute HIV infection in resource-limited settings with high HIV prevalence.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Feminino , Humanos , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Anticorpos Anti-HIV , Proteína do Núcleo p24 do HIV , Testes Imediatos , Antígenos HIV , Sensibilidade e Especificidade , HIV-1/genética , RNA , HIV-2
3.
Microb Cell Fact ; 23(1): 39, 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311724

RESUMO

BACKGROUND: Mucosal vaccines have the potential to induce protective immune responses at the sites of infection. Applying CRISPR/Cas9 editing, we aimed to develop a probiotic-based vaccine candidate expressing the HIV-1 envelope membrane-proximal external region (MPER) on the surface of E. coli Nissle 1917. RESULTS: The HIV-1 MPER epitope was successfully introduced in the porin OmpF of the E. coli Nissle 1917 (EcN-MPER) and the modification was stable over 30 passages of the recombinant bacteria on the DNA and protein level. Furthermore, the introduced epitope was recognized by a human anti-HIV-1 gp41 (2F5) antibody using both live and heat-killed EcN-MPER, and this antigenicity was also retained over 30 passages. Whole-cell dot blot suggested a stronger binding of anti-HIV-1 gp41 (2F5) to heat-killed EcN-MPER than their live counterpart. An outer membrane vesicle (OMV) - rich extract from EcN-MPER culture supernatant was equally antigenic to anti-HIV-1 gp41 antibody which suggests that the MPER antigen could be harboured in EcN-MPER OMVs. Using quantitative ELISA, we determined the amount of MPER produced by the modified EcN to be 14.3 µg/108 cfu. CONCLUSIONS: The CRISPR/Cas9 technology was an effective method for establishment of recombinant EcN-MPER bacteria that was stable over many passages. The developed EcN-MPER clone was devoid of extraneous plasmids and antibiotic resistance genes which eliminates the risk of plasmid transfer to animal hosts, should this clone be used as a vaccine. Also, the EcN-MPER clone was recognised by anti-HIV-1 gp41 (2F5) both as live and heat-killed bacteria making it suitable for pre-clinical evaluation. Expression of OmpF on bacterial surfaces and released OMVs identifies it as a compelling candidate for recombinant epitope modification, enabling surface epitope presentation on both bacteria and OMVs. By applying the methods described in this study, we present a potential platform for cost-effective and rational vaccine antigen expression and administration, offering promising prospects for further research in the field of vaccine development.


Assuntos
HIV-1 , Vacinas , Animais , Humanos , Epitopos , Escherichia coli/genética , HIV-1/genética , Sistemas CRISPR-Cas , Anticorpos Anti-HIV
4.
Vaccines (Basel) ; 10(10)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36298532

RESUMO

Flaviviruses are a threat to public health and can cause major disease outbreaks. Tick-borne encephalitis (TBE) is caused by a flavivirus, and it is one of the most important causes of viral encephalitis in Europe and is on the rise in Sweden. As there is no antiviral treatment available, vaccination remains the best protective measure against TBE. Currently available TBE vaccines are based on formalin-inactivated virus produced in cell culture. These vaccines must be delivered by intramuscular injection, have a burdensome immunization schedule, and may exhibit vaccine failure in certain populations. This project aimed to develop an edible TBE vaccine to trigger a stronger immune response through oral delivery of viral antigens to mucosal surfaces. We demonstrated successful expression and post-translational processing of flavivirus structural proteins which then self-assembled to form virus-like particles in Nicotiana benthamiana. We performed oral toxicity tests in mice using various plant species as potential bioreactors and evaluated the immunogenicity of the resulting edible vaccine candidate. Mice immunized with the edible vaccine candidate did not survive challenge with TBE virus. Interestingly, immunization of female mice with a commercial TBE vaccine can protect their offspring against TBE virus infection.

5.
Vaccines (Basel) ; 10(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35891226

RESUMO

The detection of vaccine-induced HIV antibody responses by rapid diagnostic tests (RDTs) may confound the interpretation of HIV testing results. We assessed the impact of vaccine-induced seroreactivity (VISR) on the diagnosis of HIV in sub-Saharan Africa. Samples collected from healthy participants of HIVIS and TaMoVac HIV vaccine trials after the final vaccination were analyzed for VISR using HIV testing algorithms used in Mozambique and Tanzania that employ two sequential RDTs. The samples were also tested for VISR using Enzygnost HIV Integral 4 ELISA and HIV western blot assays. Antibody titers to subtype C gp140 were determined using an in-house enzyme-linked immunosorbent assay (ELISA). The frequency of VISR was 93.4% (128/137) by Enzygnost HIV Integral 4 ELISA, and 66.4% (91/137) by western blot assay (WHO interpretation). The proportion of vaccine recipients that would have been misdiagnosed as HIV-positive in Mozambique was half of that in Tanzania: 26.3% (36/137) and 54.0% (74/137), respectively, p < 0.0001. In conclusion, the HIV RDTs and algorithms assessed here will potentially misclassify a large proportion of the HIV vaccine recipients if no other test is used. Increased efforts are needed to develop differential serological or molecular tools for use at the point of care.

6.
BMJ Open ; 11(11): e052176, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725079

RESUMO

OBJECTIVES: The aim of this study was to determine the prevalence of infection, genotypes and risk factors for human papillomavirus (HPV) among men who have sex with men (MSM) and transgender women living with and without HIV in Pakistan. Anal infection with HPV is very common worldwide among MSM, particularly among MSM living with HIV. The high prevalence of HIV among MSM and male-to-female transgendered individuals in Pakistan is a significant health concern since access to screening and health-seeking is often delayed in this stigmatised key population. DESIGN: This cross-sectional study was conducted between March 2016 and November 2017. PARTICIPANTS, SETTING AND DATA COLLECTION: This study recruited MSM and transgender-women who self-reported to have had anal sex in the last 6 months, and were at least 18 years of age, from the sexual health and antiretroviral therapy centres. Structured questionnaires were administered, and blood samples were obtained to confirm HIV status. Anal swabs were collected for HPV-DNA detection and typing. MAIN OUTCOME MEASURES: The primary outcome was the prevalence of 'HPV-DNA infection'. The prevalence ratios (PR) were calculated using Cox proportional hazard model algorithms to analyse the association between exposure variables and HPV-infection. RESULTS: Complete data were available for 298 MSM and transgender women (HIV +n=131; HIV-n=167). The overall HPV-DNA prevalence was 65.1% and was higher in participants living with HIV as compared with HIV-negative (87% vs 48%; χ2p≤0.001). Likewise, 28.9% of participants living with HIV were infected with two or more than two types of HPV as compared with 18.8% participants without HIV(χ2 p≤0.001). The most frequent HPV type was HPV6/11 (46.9%), followed by HPV16 (35.1%), HPV18 (23.2%) and HPV35 (21.1%). HIV status (PR 2.81, 95% CI 2.16 to 3.82) and never condom use (PR 3.08, 95% CI 1.69 to 5.60)) were independently associated with prevalence of 'anal-HPV16 infection' when adjusting for confounding for age, other sexual and behavioural factors, for example, smoking and alcohol consumption. CONCLUSION: High prevalence of HPV indicates a substantial future risk of anal cancer in Pakistani MSM and transgender women, and particularly in those living with HIV. Current findings support anal Pap-smear HPV screening for this particular group and vaccination efforts for future generations.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Minorias Sexuais e de Gênero , Pessoas Transgênero , Canal Anal , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Paquistão/epidemiologia , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Prevalência , Fatores de Risco , Comportamento Sexual
7.
BMC Infect Dis ; 21(1): 1163, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789177

RESUMO

BACKGROUND: Anal squamous intraepithelial lesions (ASIL), strongly related to human papilloma virus (HPV) infection, is more prevalent among men who have sex with men (MSM). However, no such data are available for Pakistan yet, and neither HPV vaccination nor anal-cytology screening is implemented in Pakistan. The purpose of this first ever study was to assess the prevalence of HPV-related anal cytological abnormalities among MSM and transgender women living with and without HIV infection in Pakistan. METHODS: We conducted a cross-sectional study from March 2016 to November 2017 at sexual health centers run by the Perwaaz Trust and the National AIDS Control Program in Karachi. The study enrolled MSM and transgender women aged greater-than-and-equal-to-18-years who reported anal sex in the preceding 6 months. We collected two anal samples for liquid-based cytology and HPV type testing by PCR, and socio-demographic and behavioral data were collected through face-to face interviews. ASIL and its associations with biological and behavioral risk factors were analyzed through Cox regression for prevalence ratios (PR) and corresponding 95% confidence intervals (CIs). RESULTS: Out of 271 qualifying participants, 79% were MSM and 21% transgender women. The mean age was 28.8 (± 8) years. Almost 35% (93/271) of the study population had ASIL detected, ASIL was significantly more common among participants living with HIV than in HIV negative ((50/118) 42.4%; vs. (43/153) 28.1%) (p ≤ 0.001). Among ASIL, 66% (61/93) had low-grade squamous intraepithelial lesions (LSIL), and 3.6% (3/93) had high-grade squamous intraepithelial lesions (HSIL). The overall, HPV16 positivity was 35.5% (33/93) among all abnormal anal lesions and all 3 HSIL were HPV16 positive, however, HPV16 positivity could show its association with ASIL detection in univariate model only (PRcrude: 2.11(1.39-3.18)). Moreover, any HR-HPV type (PR 3.04; 95% CI 1.75-5.26), concurrent sexually transmitted infection (STI) (2.13; (1.28-3.55)) and HIV + /HPV + coinfection (1.75; (1.07-2.88)) remained independently associated with ASIL in the multivariate model. CONCLUSIONS: Abnormal anal cytology among MSM and transgender is prevalent enough to consider optimal screening regimens. Further studies are required to see if periodic anal cytology can be made part of HIV care and treatment programs among MSM in Pakistan.


Assuntos
Alphapapillomavirus , Infecções por HIV , Minorias Sexuais e de Gênero , Lesões Intraepiteliais Escamosas , Pessoas Transgênero , Adulto , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Paquistão/epidemiologia , Papillomaviridae/genética , Comportamento Sexual
8.
PLoS One ; 16(5): e0251644, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33984060

RESUMO

OBJECTIVES: Comprehensive cost-effectiveness analyses of introducing varicella and/or herpes zoster vaccination in the Swedish national vaccination programme. DESIGN: Cost-effectiveness analyses based on epidemiological results from a specifically developed transmission model. SETTING: National vaccination programme in Sweden, over an 85- or 20-year time horizon depending on the vaccination strategy. PARTICIPANTS: Hypothetical cohorts of people aged 12 months and 65-years at baseline. INTERVENTIONS: Four alternative vaccination strategies; 1, not to vaccinate; 2, varicella vaccination with one dose of the live attenuated vaccine at age 12 months and a second dose at age 18 months; 3, herpes zoster vaccination with one dose of the live attenuated vaccine at 65 years of age; and 4, both vaccine against varicella and herpes zoster with the before-mentioned strategies. MAIN OUTCOME MEASURES: Accumulated cost and quality-adjusted life years (QALY) for each strategy, and incremental cost-effectiveness ratios (ICER). RESULTS: It would be cost-effective to vaccinate against varicella (dominant), but not to vaccinate against herpes zoster (ICER of EUR 200,000), assuming a cost-effectiveness threshold of EUR 50,000 per QALY. The incremental analysis between varicella vaccination only and the combined programme results in a cost per gained QALY of almost EUR 1.6 million. CONCLUSIONS: The results from this study are central components for policy-relevant decision-making, and suggest that it was cost-effective to introduce varicella vaccination in Sweden, whereas herpes zoster vaccination with the live attenuated vaccine for the elderly was not cost-effective-the health effects of the latter vaccination cannot be considered reasonable in relation to its costs. Future observational and surveillance studies are needed to make reasonable predictions on how boosting affects the herpes zoster incidence in the population, and thus the cost-effectiveness of a vaccination programme against varicella. Also, the link between herpes zoster and sequelae need to be studied in more detail to include it suitably in health economic evaluations.


Assuntos
Vacina contra Varicela/administração & dosagem , Varicela/prevenção & controle , Vacina contra Herpes Zoster/administração & dosagem , Herpes Zoster/prevenção & controle , Programas de Imunização/economia , Adolescente , Adulto , Idoso , Varicela/economia , Varicela/epidemiologia , Varicela/transmissão , Vacina contra Varicela/economia , Criança , Pré-Escolar , Análise Custo-Benefício , Herpes Zoster/economia , Herpes Zoster/epidemiologia , Herpes Zoster/transmissão , Vacina contra Herpes Zoster/economia , Herpesvirus Humano 3/imunologia , Herpesvirus Humano 3/patogenicidade , Humanos , Programas de Imunização/métodos , Programas de Imunização/estatística & dados numéricos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Suécia/epidemiologia , Resultado do Tratamento , Ativação Viral , Adulto Jovem
9.
Viruses ; 14(1)2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35062228

RESUMO

BACKGROUND: Human papillomavirus (HPV) infection is now a well-established cause of cervical cancer and other anogenital cancers. An association between human immunodeficiency virus (HIV) infection and higher HPV incidence and prevalence are commonly reported. This study was conducted to demonstrate HPV prevalence, genotypes and its characteristics, according to the HIV status in women from Maputo in Mozambique. METHODS: A total of 233 participants with ages ranging from fourteen to forty-five were included. Cervical samples were collected, DNA extracted, and HPV genotyping was performed using the HPV Direct Flow CHIP Kit. RESULTS: In total, 177 HIV-negative and 56 HIV-positive women were included in the analysis. The overall HPV prevalence was 63% and was significantly higher among HIV-positive women (79% versus 58% among HIV-negative women; p = 0.005). The prevalence of multiple HPV type infections was 32%. High-risk HPV types 52, 68, 35, 18 and 16 were the most frequent. A higher proportion of HIV-positive women had multiple HPV types compared with HIV-negative women. CONCLUSIONS: This study demonstrated a high prevalence of HPV in the study cohort. HIV-positive women were identified as having the highest HPV prevalence and infection with multiple HPV types across all ages. High-risk genotypes were the most commonly found.


Assuntos
Alphapapillomavirus/genética , Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Adolescente , Adulto , Alphapapillomavirus/isolamento & purificação , Colo do Útero/virologia , Estudos de Coortes , Estudos Transversais , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Moçambique/epidemiologia , Infecções por Papillomavirus/epidemiologia , Prevalência , Adulto Jovem
10.
Parasit Vectors ; 13(1): 185, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268924

RESUMO

BACKGROUND: Tick distribution in Sweden has increased in recent years, with the prevalence of ticks predicted to spread towards the northern parts of the country, thus increasing the risk of tick-borne zoonoses in new regions. Tick-borne encephalitis (TBE) is the most significant viral tick-borne zoonotic disease in Europe. The disease is caused by TBE virus (TBEV) infection which often leads to severe encephalitis and myelitis in humans. TBEV is usually transmitted to humans via tick bites; however, the virus can also be excreted in the milk of goats, sheep and cattle and infection may then occur via consumption of unpasteurised dairy products. Virus prevalence in questing ticks is an unreliable indicator of TBE infection risk as viral RNA is rarely detected even in large sample sizes collected at TBE-endemic areas. Hence, there is a need for robust surveillance techniques to identify emerging TBEV risk areas at early stages. METHODS: Milk and colostrum samples were collected from sheep and goats in Örebro County, Sweden. The milk samples were analysed for the presence of TBEV antibodies by ELISA and validated by western blot in which milk samples were used to detect over-expressed TBEV E-protein in crude cell extracts. Neutralising titers were determined by focus reduction neutralisation test (FRNT). The stability of TBEV in milk and colostrum was studied at different temperatures. RESULTS: In this study we have developed a novel strategy to identify new TBEV foci. By monitoring TBEV antibodies in milk, we have identified three previously unknown foci in Örebro County which also overlap with areas of TBE infection reported during 2009-2018. In addition, our data indicates that keeping unpasteurised milk at 4 °C will preserve the infectivity of TBEV for several days. CONCLUSIONS: Altogether, we report a non-invasive surveillance technique for revealing risk areas for TBE in Sweden, by detecting TBEV antibodies in sheep milk. This approach is robust and reliable and can accordingly be used to map TBEV "hotspots". TBEV infectivity in refrigerated milk was preserved, emphasising the importance of pasteurisation (i.e. 72 °C for 15 s) prior to consumption.


Assuntos
Anticorpos Antivirais/análise , Encefalite Transmitida por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/veterinária , Monitoramento Epidemiológico/veterinária , Leite/imunologia , Animais , Colostro/imunologia , Vírus da Encefalite Transmitidos por Carrapatos , Feminino , Cabras/imunologia , Humanos , Testes de Neutralização , RNA Viral/genética , Ovinos/imunologia , Suécia/epidemiologia , Zoonoses/parasitologia , Zoonoses/transmissão
12.
Lancet HIV ; 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30392769

RESUMO

BACKGROUND: HIV type 2 (HIV-2) is considered more benign and has fewer pathogenic consequences than HIV type 1 (HIV-1) for most infected individuals. However, reliable estimates of time to AIDS and mortality among those with HIV-2 infection are absent. We therefore aimed to compare the time to AIDS and mortality, and the CD4 T-cell dynamics between those infected with HIV-1 and HIV-2. METHODS: We did a prospective open cohort study. We included all police officers with regular employment from police stations in both urban and rural areas of Guinea-Bissau since Feb 6, 1990. We continued to include participants until Sept 28, 2009, and follow-up of HIV-1-positive and HIV-2-positive individuals continued until Sept 28, 2013. We collected blood samples at enrolment and at scheduled annual follow-up visits at police stations. We analysed longitudinal data from individuals infected with HIV-1 and HIV-2 according to time to AIDS, time to death, and T-cell dynamics. Time of HIV infection was estimated as the mid-timepoint between last HIV-seronegative and first HIV-seropositive sample. Data from an additional 2984 HIV-uninfected individuals from the same population were analysed to assess the effect of natural mortality on HIV-related mortality. FINDINGS: 872 participants tested HIV positive during the 23-year study period: 408 were infected with HIV-1 (183 infected before and 225 infected after enrolment) and 464 were infected with HIV-2 (377 before and 87 after enrolment). The median time from HIV infection to development of AIDS was 6·2 years (95% CI 5·4-7·1) for HIV-1 infection and 14·3 years (10·7-18·0) for HIV-2 infection (p<0·0001). The median survival time after HIV infection was 8·2 years (95% CI 7·5-8·9) for HIV-1 infection and 15·6 years (12·0-19·2) for HIV-2 infection (p<0·0001). Individuals who were infected with HIV-1 or HIV-2 before enrolment showed similar results. Comparison with uninfected individuals indicated limited confounding contribution from natural mortality. Mean CD4 percentages were higher in individuals with HIV-2 than in those with HIV-1 during early infection (28·0% [SE 1·3] vs 22·3% [1·7]; p=0·00094) and declined at a slower rate (0·4% [0·2] vs 0·9% [0·2] per year; p=0·028). HIV-2-infected individuals developed clinical AIDS at higher mean CD4 percentages (18·2%, IQR 7·2-25·4) than HIV-1-infected individuals (8·2%, 3·0-13·8; p<0·0001). INTERPRETATION: Our results show that both HIV-1-infected and HIV-2-infected individuals have a high probability of developing and dying from AIDS without antiretroviral treatment. FUNDING: Swedish International Development Agency, Swedish Research Council, Swedish Society of Medical Research, Medical Faculty at Lund University, and Region Skåne Research and Development.

13.
J Virol Methods ; 260: 70-74, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30006102

RESUMO

BACKGROUND: Human T-lymphotrophic virus (HTLV) types 1 and 2 cause lifelong infection whereby most infected individuals are asymptomatic whilst a minority develop infection-related disease. These latter patients invariably have been found to have high proviral load (PVL). Therefore, infected patients are monitored by determining the proportion of lymphocytes that are infected with HTLV-1/2. An increase in PVL has been shown to represent an increasing risk of developing HTLV-associated diseases. Monitoring of PVL requires a reliable and sensitive method. In this study assays based on droplet digital PCR (ddPCR) were established and evaluated for detection and quantification of HTLV-1/2. OBJECTIVES: To develop two parallel assays to detect the tax genes and determine the PVL of HTLV-1 and -2. STUDY DESIGN: Sixty-seven clinical samples from patients infected with HTLV-1 or HTLV-2 were analysed. The samples had previously been analysed with a qPCR and a comparison between ddPCR and qPCR was performed. The specificity of the assays were determined by analyzing samples from 20 healthy blood donors. RESULTS: The ddPCR was a stable and sensitive method for detection and quantification of HTLV-1 and -2. When comparing the qPCR and ddPCR the correlation was high (Pearsons correlation coefficient 0.96). The variability of the ddPCR was very low with intra-assay coefficient of variation (CV) of 0.97-3.3% (HTLV-1) and 1.7-8.2% (HTLV-2) and inter-assay CV of 1.8-6.1% (HTLV-1) and 1.2-12.9% (HTLV-2). CONCLUSIONS: The ddPCR reliably quantified HTLV DNA in clinical samples and could be a useful tool for monitoring of PVLs in HTLV-infected individuals.


Assuntos
Infecções por HTLV-I/sangue , Infecções por HTLV-II/sangue , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Provírus/genética , Biomarcadores/sangue , Buffy Coat/virologia , Teste em Amostras de Sangue Seco , Genes pX/genética , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Linfócitos T/virologia
14.
AIDS Res Hum Retroviruses ; 34(2): 193-205, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28969431

RESUMO

We assessed the safety and immunogenicity of HIV-DNA priming using Zetajet™, a needle-free device intradermally followed by intramuscular HIV-MVA boosts, in 24 healthy Mozambicans. Volunteers were randomized to receive three immunizations of 600 µg (n = 10; 2 × 0.1 ml) or 1,200 µg (n = 10; 2 × 0.2 ml) of HIV-DNA (3 mg/ml), followed by two boosts of 108 pfu HIV-MVA. Four subjects received placebo saline injections. Vaccines and injections were safe and well tolerated with no difference between the two priming groups. After three HIV-DNA immunizations, IFN-γ ELISpot responses to Gag were detected in 9/17 (53%) vaccinees, while none responded to Envelope (Env). After the first HIV-MVA, the overall response rate to Gag and/or Env increased to 14/15 (93%); 14/15 (93%) to Gag and 13/15 (87%) to Env. There were no significant differences between the immunization groups in frequency of response to Gag and Env or magnitude of Gag responses. Env responses were significantly higher in the higher dose group (median 420 vs. 157.5 SFC/million peripheral blood mononuclear cell, p = .014). HIV-specific antibodies to subtype C gp140 and subtype B gp160 were elicited in all vaccinees after the second HIV-MVA, without differences in titers between the groups. Neutralizing antibody responses were not detected. Two (13%) of 16 vaccinees, one in each of the priming groups, exhibited antibodies mediating antibody-dependent cellular cytotoxicity to CRF01_AE. In conclusion, HIV-DNA vaccine delivered intradermally in volumes of 0.1-0.2 ml using Zetajet was safe and well tolerated. Priming with the 1,200 µg dose of HIV-DNA generated higher magnitudes of ELISpot responses to Env.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Esquemas de Imunização , Vacinas de DNA/imunologia , Vacinas contra a AIDS/efeitos adversos , Administração Cutânea , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , ELISPOT , Feminino , Anticorpos Anti-HIV/sangue , HIV-1/genética , Humanos , Injeções Intramusculares , Interferon gama/análise , Leucócitos Mononucleares/imunologia , Masculino , Moçambique , Placebos/administração & dosagem , Resultado do Tratamento , Vacinas de DNA/administração & dosagem , Vacinas de DNA/efeitos adversos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Voluntários , Adulto Jovem , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
15.
BMJ Open ; 7(7): e015653, 2017 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-28716790

RESUMO

OBJECTIVES: Human papillomavirus (HPV) is a well-known cause of cervical cancer, the second most frequent cancer in female African populations. This study aimed at determining the prevalence of HPV infections and the genotype distribution in young adults aged 18-24, in Maputo city, Mozambique, and to assess the suitability of commercially available HPV vaccines. METHODS: This cross-sectional study was conducted between 2009 and 2011 at a youth clinic in Maputo Central Hospital. Cervical and urethral samples were obtained from 236 women and 176 men, respectively. Demographic and behavioural data were collected using structured questionnaires. HPV genotyping was performed for 35 different high, probably or possibly high-risk and low-risk HPV types using the CLART Human Papillomavirus 2. RESULTS: HPV prevalence was 168/412 (40.8%; 95% CI 36.0 to 45.5) and was significantly higher in women than in men (63.6%vs10.2%). HPV52 was the most frequent type found in women, followed by HPV35, -16,-53, -58,-6 and -51. In men, HPV51 ranked the highest, followed by HPV6, -11,-52, -59 and -70. HIV infection and sexual debut before 18 years of age were associated with multiple HPV infections (OR 3.03; 95% CI 1.49 to 6.25 and OR 6.03; 95% CI 1.73 to 21.02, respectively). Women had a significantly higher HPV infection prevalence than men (p<0.001). The 9-valent HPV vaccine would cover 36.8% of the high-risk genotypes circulating in women in this study, compared with 26.3% and 15.8% coverage by the bivalent and quadrivalent vaccines, respectively. CONCLUSION: This study confirmed the high burden of HPV infections in young women in Maputo city, Mozambique. The HPV prevalence was associated with high-risk sexual behaviour. Sex education and sexually transmitted infection prevention interventions should be intensified in Mozambique. Only a proportion of the high-risk HPV genotypes (37%) were covered by currently available vaccines.


Assuntos
Papillomaviridae/classificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Adolescente , Estudos Transversais , Feminino , Genótipo , Infecções por HIV/epidemiologia , Humanos , Modelos Logísticos , Masculino , Moçambique/epidemiologia , Distribuição por Sexo , Neoplasias do Colo do Útero/prevenção & controle , Adulto Jovem
16.
BMC Womens Health ; 17(1): 40, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28576143

RESUMO

BACKGROUND: Previous studies were conflicting regarding the associations between HPV vaccination, cervical cancer risk perceptions, high-risk sexual behaviors and STIs. This study compared the HPV-vaccinated and non-vaccinated young women in Uganda regarding cervical cancer risk perceptions, high-risk sexual behaviors, syphilis and HIV infections 5 years after vaccine implementation. METHODS: This was a population-based comparative cross-sectional survey conducted in Uganda. The 438 participants were sexually active young women aged 15-24 years and mean age was 18.6 (SD 1.4). The majority (53.0%) were HPV-vaccinated in 2008 without assessment of sexual activity prior to HPV vaccination. Upon verbal assessment of sexual activity at the time of follow-up, data were collected using a questionnaire and laboratory testing of blood samples for syphilis and HIV infections. RESULTS: There were no significant differences between the HPV-vaccinated and non-vaccinated groups regarding the prevalence of high-risk sexual behaviors, syphilis and HIV infections. Cervical cancer risk perceptions and age at sexual debut were nonetheless significantly lower among the vaccinated group compared to their non-vaccinated counterparts. However, HPV vaccination was not significantly associated to cervical cancer risk perceptions and early age at sexual debut in multivariate logistic regression analysis. CONCLUSIONS: We found no associations between HPV vaccination, cervical cancer risk perceptions, high-risk sexual behaviors, syphilis and HIV infections among young women in Uganda 5 years after vaccine implementation. Young girls in the study population were found to be sexually active at a young age, affirming the importance of targeting girls of younger age for HPV vaccination.


Assuntos
Assunção de Riscos , Comportamento Sexual/psicologia , Infecções Sexualmente Transmissíveis/psicologia , Neoplasias do Colo do Útero/psicologia , Vacinação/psicologia , Adolescente , Fatores Etários , Estudos Transversais , Feminino , Seguimentos , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Modelos Logísticos , Análise Multivariada , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/psicologia , Vacinas contra Papillomavirus/uso terapêutico , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Uganda/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Adulto Jovem
17.
APMIS ; 124(12): 1078-1086, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27859689

RESUMO

The asymptomatic nature of most Chlamydia trachomatis infections and the lack of appropriate effects by current prevention and management call for vaccine development. We evaluated a recombinant subunit vaccine candidate based on the major outer membrane protein variable segments 2 and 4 (MOMP VS2/4). To achieve maximal immunogenicity and ease of production and purification, MOMP VS2/4 was constructed by using highly immunogenic sequences of MOMP only, thereby minimizing the presence of hydrophobic regions, and spacing the immunogenic epitopes with a flexible amino acid sequence. A purification tag was also added. The MOMP VS2/4 was given intranasally, with or without intravaginal boost, with cholera toxin (CT) adjuvant to C57BL/6 mice, which were screened for immunogenicity and protection against a live challenge infection with C. trachomatis serovar D. Bacterial shedding, cell-mediated responses, and antibody responses were monitored. Immunized mice exhibited significantly less bacterial shedding and were better protected against infertility as compared to unimmunized control mice. Immunizations stimulated both systemic and local specific antibody (IgG1, IgG2c, and IgA) responses, and primed T cells that produced interferon-γ and interleukins 13 and 17 upon challenge with recall antigen. Thus, MOMP VS2/4, in combination with CT adjuvant, stimulated Th1, Th2, and Th17 effector cells, and generated protective immunity associated with less pathology. We regard MOMP VS2/4 as a promising candidate for further development into a mucosal chlamydial vaccine.


Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Chlamydia trachomatis/imunologia , Linfogranuloma Venéreo/prevenção & controle , Porinas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Intranasal , Administração Intravaginal , Animais , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Derrame de Bactérias , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Toxina da Cólera/administração & dosagem , Citocinas/metabolismo , Modelos Animais de Doenças , Epitopos/genética , Epitopos/imunologia , Feminino , Infertilidade/prevenção & controle , Masculino , Camundongos Endogâmicos C57BL , Porinas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/imunologia , Resultado do Tratamento , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
18.
PLoS One ; 11(8): e0160099, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27482705

RESUMO

The objective of this study was to determine the prevalence and some predictors for vaccine and non-vaccine types of HPV infections among bivalent HPV vaccinated and non-vaccinated young women in Uganda. This was a comparative cross sectional study 5.5 years after a bivalent HPV 16/18 vaccination (Cervarix®, GlaxoSmithKline, Belgium) pilot project in western Uganda. Cervical swabs were collected between July 2014-August 2014 and analyzed with a HPV genotyping test, CLART® HPV2 assay (Genomica, Madrid Spain) which is based on PCR followed by microarray for determination of genotype. Blood samples were also tested for HIV and syphilis infections as well as CD4 and CD8 lymphocyte levels. The age range of the participants was 15-24 years and mean age was 18.6(SD 1.4). Vaccine-type HPV-16/18 strains were significantly less prevalent among vaccinated women compared to non-vaccinated women (0.5% vs 5.6%, p 0.006, OR 95% CI 0.08(0.01-0.64). At type-specific level, significant difference was observed for HPV16 only. Other STIs (HIV/syphilis) were important risk factors for HPV infections including both vaccine types and non-vaccine types. In addition, for non-vaccine HPV types, living in an urban area, having a low BMI, low CD4 count and having had a high number of life time sexual partners were also significant risk factors. Our data concurs with the existing literature from other parts of the world regarding the effectiveness of bivalent HPV-16/18 vaccine in reducing the prevalence of HPV infections particularly vaccine HPV- 16/18 strains among vaccinated women. This study reinforces the recommendation to vaccinate young girls before sexual debut and integrate other STI particularly HIV and syphilis interventions into HPV vaccination packages.


Assuntos
Papillomavirus Humano 16/efeitos dos fármacos , Papillomavirus Humano 18/efeitos dos fármacos , Vacinação em Massa , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Adolescente , Coinfecção , Estudos Transversais , Feminino , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/microbiologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/imunologia , Humanos , Programas de Imunização/organização & administração , Infecções por Papillomavirus/imunologia , Projetos Piloto , Prevalência , Sífilis/epidemiologia , Sífilis/microbiologia , Uganda/epidemiologia , Adulto Jovem
19.
Protein Expr Purif ; 127: 61-67, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27402440

RESUMO

The zoonotic Rift Valley fever virus affects livestock and humans in Africa and on the Arabian Peninsula. The economic impact of this pathogen due to livestock losses, as well as its relevance to public health, underscores the importance of developing effective and easily distributed vaccines. Vaccines that can be delivered orally are of particular interest. Here, we report the expression in transformed plants (Arabidopsis thaliana) of Rift Valley fever virus antigens. The antigens used in this study were the N protein and a deletion mutant of the Gn glycoprotein. Transformed lines were analysed for specific mRNA and protein content by RT-PCR and Western blotting, respectively. Furthermore, the plant-expressed antigens were evaluated for their immunogenicity in mice fed the transgenic plants. After oral intake of fresh transgenic plant material, a proportion of the mice elicited specific IgG antibody responses, as compared to the control animals that were fed wild-type plants and of which none sero-converted. Thus, we show that transgenic plants can be readily used to express and produce Rift Valley Fever virus proteins, and that the plants are immunogenic when given orally to mice. These are promising findings and provide a basis for further studies on edible plant vaccines against the Rift Valley fever virus.


Assuntos
Anticorpos Antivirais/imunologia , Antígenos Virais , Arabidopsis , Imunoglobulina G/imunologia , Plantas Geneticamente Modificadas , Vírus da Febre do Vale do Rift , Proteínas Virais , Vacinas Virais , Administração Oral , Animais , Antígenos Virais/biossíntese , Antígenos Virais/genética , Antígenos Virais/imunologia , Antígenos Virais/farmacologia , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/metabolismo , Imunogenicidade da Vacina , Camundongos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Vírus da Febre do Vale do Rift/genética , Vírus da Febre do Vale do Rift/imunologia , Proteínas Virais/biossíntese , Proteínas Virais/genética , Proteínas Virais/imunologia , Proteínas Virais/farmacologia , Vacinas Virais/biossíntese , Vacinas Virais/genética , Vacinas Virais/imunologia
20.
Plant Biotechnol J ; 14(4): 1106-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26403330

RESUMO

Although much explored, oral tolerance for treatment of autoimmune diseases still awaits the establishment of novel and effective vectors. We investigated whether the tolerogenic CTA1(R7K)-COL-DD fusion protein can be expressed in edible plants, to induce oral tolerance and protect against arthritis. The fusion protein was recombinantly expressed in Arabidopsis thaliana plants, which were fed to H-2(q) -restricted DBA/1 mice to assess the preventive effect on collagen-induced arthritis (CIA). The treatment resulted in fewer mice exhibiting disease and arthritis scores were significantly reduced. Immune suppression was evident in treated mice, and serum biomarkers for inflammation as well as anticollagen IgG responses were reduced. In spleen and draining lymph nodes, CD4(+) T-cell responses were reduced. Concomitant with a reduced effector T-cell activity with lower IFNγ, IL-13 and IL-17A production, we observed an increase in IL-10 production to recall antigen stimulation in vitro, suggesting reduced Th1, Th2 and Th17 activity subsequent to up-regulated IL-10 and regulatory T-cell (Treg) functions. This study shows that edible plants expressing a tolerogen were effective at stimulating CD4 T-cell tolerance and in protecting against CIA disease. Our study conveys optimism as to the potential of using edible plants for oral treatment of rheumatoid arthritis.


Assuntos
Arabidopsis/genética , Artrite Experimental/prevenção & controle , Toxina da Cólera/genética , Toxina da Cólera/farmacologia , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/dietoterapia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Regulação da Expressão Gênica de Plantas , Interleucina-10/metabolismo , Masculino , Camundongos Endogâmicos DBA , Células Th17/efeitos dos fármacos , Células Th17/imunologia
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