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1.
PLoS One ; 19(9): e0307781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39240843

RESUMO

Sexually transmitted infections (STIs) have a profound impact on sexual and reproductive health worldwide. Syphilis, gonorrhea, chlamydia, and trichomoniasis are four currently curable STIs. However, most STI cases are asymptomatic and not detected without laboratory diagnostics. Hepatitis B virus, herpes simplex virus, human immunodeficiency virus (HIV), and human papillomavirus (HPV) are four viral and incurable infections, but they can be mitigated by treatment. We investigated the prevalence of selected sexually transmitted pathogens and their relationship with HPV and HIV infection in women from Maputo, the capital of Mozambique. A cross-sectional study was conducted on 233 non-pregnant women seeking health care relating to gynecological symptoms in Mavalane Health facilities in Maputo, between the 1st of February 2018 and the 30th of July 2019. Cervical brush samples were collected and DNA was extracted. Selected STIs including HPV were detected using multiplex STD and HPV Direct Flow Chip Kits through a manual Hybrispot platform (Vitro, Master Diagnostica, Sevilla, Spain). HIV testing was performed using rapid tests: Determine HIV 1/2 test (Alere Abbott Laboratories, Tokyo, Japan) for screening, and UniGold HIV (Trinity Biotech, Ireland) for confirmation. All women (n = 233) were negative for Haemophilus ducreyi and Herpes Simplex Virus-1 (HSV-1). Among the 233 women, a high prevalence of STIs was found (89%), 63% of the women were positive for HPV and 24% were HIV positive. Treponema pallidum (TP), Trichomonas vaginalis (TV), Herpes Simplex Virus-2 (HSV-2), and Chlamydia trachomatis (CT) were detected in 17%, 14%, 8%, and 8% of the women, respectively. As a common phenomenon, vaginal discharge (90%) was the lower genital tract symptom reported by the majority of the women. Co-infection with any STI and HPV was detected in 56% (130/233) while 45% (59/130) of the co-infections were with high-risk HPV (hrHPV) genotypes. Among the HPV-positive participants, infection by TP was the most prevalent (27%). In total, 28% (66/233) of the participants were positive for any hrHPV genotypes. Co-infection with any STI and HIV was found in 15% (34/233) of the study participants. There was a significant association between HPV infection and TP (p = 0.039) and HSV-2 (p = 0.005). TV, TP, and CT-S1-CT-S2 positivity were significantly more prevalent in HIV-positive participants. Pathobionts Ureaplasma urealyticum/parvum and Mycoplasma hominis were detected in 84.0% (195/233) and 45% (105/233), respectively. This present study describes a high prevalence of STIs. Co-infection between HPV and STIs was found in the majority of the study subjects. The high prevalence of HPV emphasizes the need for HPV vaccination to prevent cervical cancer in this population. Management of STIs is also important in women presenting with gynecological symptoms.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Infecções Sexualmente Transmissíveis , Humanos , Feminino , Moçambique/epidemiologia , Adulto , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Estudos Transversais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/microbiologia , Adulto Jovem , Prevalência , Adolescente , Pessoa de Meia-Idade , Coinfecção/epidemiologia , Sífilis/epidemiologia , Sífilis/complicações , Papillomaviridae/isolamento & purificação , Papillomaviridae/genética
2.
Viruses ; 16(8)2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39205288

RESUMO

BACKGROUND: Human papillomavirus 16 (HPV16) is an oncogenic virus responsible for the majority of invasive cervical cancer cases worldwide. Due to genetic modifications, some variants are more oncogenic than others. We analysed the HPV16 phylogeny in HPV16-positive cervical Desoxyribonucleic Acid (DNA) samples collected from South African and Mozambican women to detect the circulating lineages. METHODS: Polymerase chain reaction (PCR) amplification of the long control region (LCR) and 300 nucleotides of the E6 region was performed using HPV16-specific primers on HPV16-positive cervical samples collected in women from South Africa and Mozambique. HPV16 sequences were obtained through Next Generation Sequencing (NGS) methods. Geneious prime and MEGA 11 software were used to align the sequences to 16 HPV16 reference sequences, gathering the A, B, C, and D lineages and generating the phylogenetic tree. Single nucleotide polymorphisms (SNPs) in the LCR and E6 regions were analysed and the phylogenetic tree was generated using Geneious Prime software. RESULTS: Fifty-eight sequences were analysed. Of these sequences, 79% (46/58) were from women who had abnormal cervical cytology. Fifteen SNPs in the LCR and eight in the E6 region were found to be the most common in all sequences. The phylogenetic analysis determined that 45% of the isolates belonged to the A1 sublineage (European variant), 34% belonged to the C1 sublineage (African 1 variant), 16% belonged to the B1 and B2 sublineage (African 2 variant), two isolates belonged to the D1-3 sublineages (Asian-American variant), and one to the North American variant. CONCLUSIONS: The African and European HPV16 variants were the most common circulating lineages in South African and Mozambican women. A high-grade squamous intraepithelial lesion (HSIL) was the most common cervical abnormality observed and linked to European and African lineages. These findings may contribute to understanding molecular HPV16 epidemiology in South Africa and Mozambique.


Assuntos
Papillomavirus Humano 16 , Infecções por Papillomavirus , Filogenia , Neoplasias do Colo do Útero , Humanos , Feminino , Moçambique/epidemiologia , África do Sul/epidemiologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/classificação , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto , Colo do Útero/virologia , Colo do Útero/patologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , DNA Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas Oncogênicas Virais/genética , Adulto Jovem , Citologia
3.
Viruses ; 16(1)2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275972

RESUMO

BACKGROUND: Human papillomavirus (HPV) vaccination programs are a key intervention in protecting individuals against HPV-related disease. HIV1-infected individuals are at increased risk of HPV-associated cancers. This study was conducted to evaluate the potential role of prophylactic HPV vaccines in preventing new HPV infections among participants with perinatally acquired HIV who received the quadrivalent HPV vaccine at least five years before this study. METHODS: This cross-sectional study was conducted at Newlands Clinic, Harare, Zimbabwe. The clinic provided the Gardasil quadrivalent HPV vaccine (4vHPV) to 624 adolescents living with HIV starting in December 2015. Vaginal and penile swabs were collected and tested for HPV types from the study participants who had received the 4vHPV vaccine 5-6 years before enrolment. RESULTS: We present the results of 98 participants (44.6% female) vaccinated at a median age of 15 years (IQR 12-16). The mean amount of time since vaccination was 6 years (SD: ±0.4). The HPV-positive rate amongst the analyzed swabs was 69% (68/98). Among 30/98 (31%) HPV-positive participants, 13/98 (13%) had low-risk HPV types, and 17/98 (17%) had high-risk HPV types. Twelve participants tested positive for HPV18, only one participant tested positive for HPV16, and an additional four (4.3%) tested positive for either type 6 or 11, with respect to vaccine-preventable low-risk HPV types. CONCLUSION: The Gardasil quadrivalent HPV vaccine (4vHPV) was expected to protect against infection with HPV types 16, 18, 6, and 11. We demonstrated a possible waning of immunity to HPV18 in 17% of the participants, and an associated loss in cross-protection against HPV45. We observed a relatively high prevalence of 'opportunistic non-vaccine HPV types' or 'ecological niche occupiers' in this cohort, and suggest further research on the involvement of these types in cervical and other genital cancers. Our study is one of the few, if not the first, to report on HPV vaccine immunoprotection among people living with HIV (PLWH), thereby setting a baseline for further studies on HPV vaccine effectiveness among PLWH.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Adolescente , Criança , Masculino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Estudos Transversais , Zimbábue/epidemiologia , Vacinação , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Infecções por HIV/complicações
4.
Viruses ; 15(7)2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37515128

RESUMO

Human papillomavirus (HPV) is causally associated with 5% of cancers, including cancers of the cervix, penis, vulva, vagina, anus and oropharynx. The most carcinogenic HPV is HPV-16, which dominates the types causing cancer. There is also sufficient evidence that HPV types 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59 cause cervical cancer. The L1 protein, which, when assembled into virus-like particles, induces HPV-type-specific neutralising antibodies, forms the basis of all commercial HPV vaccines. There are six licensed prophylactic HPV vaccines: three bivalent, two quadrivalent and one nonavalent vaccine. The bivalent vaccines protect from HPV types 16 and 18, which are associated with more than 70% of cervical cancers. Prophylactic vaccination targets children before sexual debut, but there are now catch-up campaigns, which have also been shown to be beneficial in reducing HPV infection and disease. HPV vaccination of adults after treatment for cervical lesions or recurrent respiratory papillomatosis has impacted recurrence. Gender-neutral vaccination will improve herd immunity and prevent infection in men and women. HPV vaccines are immunogenic in people living with HIV, but more research is needed on the long-term impact of vaccination and to determine whether further boosters are required.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adulto , Masculino , Criança , Humanos , Feminino , Papillomavirus Humano , Vacinologia , Neoplasias do Colo do Útero/prevenção & controle , Papillomavirus Humano 16 , Vacinas Combinadas
5.
Front Immunol ; 14: 1143034, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063887

RESUMO

East Coast fever is an acute bovine disease caused by the apicomplexan parasite Theileria parva and is regarded as one of the most important tick-vectored diseases in Africa. The current vaccination procedure has many drawbacks, as it involves the use of live T. parva sporozoites. As a novel vaccination strategy, we have constructed the recombinant lumpy skin disease virus (LSDV) named LSDV-SODis-p67HA-BLV-Gag, encoding a modified form of the T. parva p67 surface antigen (p67HA), as well as the bovine leukemia virus (BLV) gag gene for the formation of virus-like particles (VLPs) to potentially enhance p67 immunogenicity. In place of the native sequence, the chimeric p67HA antigen has the human tissue plasminogen activator signal sequence and the influenza hemagglutinin A2 transmembrane domain and cytoplasmic tail. p67HA was detected on the surface of infected cells, and VLPs comprising BLV Gag and p67HA were produced. We also show that higher multiple bands observed in western blot analysis are due to glycosylation of p67. The two vaccines, pMExT-p67HA (DNA) and LSDV-SODis-p67HA-BLV-Gag, were tested for immunogenicity in mice. p67-binding antibodies were produced by vaccinated animals, with higher titers detected in mice vaccinated with the recombinant LSDV. This candidate dual vaccine warrants further testing in cattle.


Assuntos
Doença Nodular Cutânea , Vacinas Protozoárias , Theileriose , Bovinos , Humanos , Camundongos , Animais , Theileriose/prevenção & controle , Theileriose/parasitologia , Ativador de Plasminogênio Tecidual , Proteínas de Protozoários , Doença Nodular Cutânea/prevenção & controle
6.
Front Plant Sci ; 14: 1146234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959936

RESUMO

Molecular farming of vaccines has been heralded as a cheap, safe and scalable production platform. In reality, however, differences in the plant biosynthetic machinery, compared to mammalian cells, can complicate the production of viral glycoproteins. Remodelling the secretory pathway presents an opportunity to support key post-translational modifications, and to tailor aspects of glycosylation and glycosylation-directed folding. In this study, we applied an integrated host and glyco-engineering approach, NXS/T Generation™, to produce a SARS-CoV-2 prefusion spike trimer in Nicotiana benthamiana as a model antigen from an emerging virus. The size exclusion-purified protein exhibited a characteristic prefusion structure when viewed by transmission electron microscopy, and this was indistinguishable from the equivalent mammalian cell-produced antigen. The plant-produced protein was decorated with under-processed oligomannose N-glycans and exhibited a site occupancy that was comparable to the equivalent protein produced in mammalian cell culture. Complex-type glycans were almost entirely absent from the plant-derived material, which contrasted against the predominantly mature, complex glycans that were observed on the mammalian cell culture-derived protein. The plant-derived antigen elicited neutralizing antibodies against both the matched Wuhan and heterologous Delta SARS-CoV-2 variants in immunized hamsters, although titres were lower than those induced by the comparator mammalian antigen. Animals vaccinated with the plant-derived antigen exhibited reduced viral loads following challenge, as well as significant protection from SARS-CoV-2 disease as evidenced by reduced lung pathology, lower viral loads and protection from weight loss. Nonetheless, animals immunized with the mammalian cell-culture-derived protein were better protected in this challenge model suggesting that more faithfully reproducing the native glycoprotein structure and associated glycosylation of the antigen may be desirable.

7.
J Cancer Educ ; 38(1): 146-152, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34581972

RESUMO

Little is known about the level of knowledge and awareness with regard to human papillomavirus (HPV) and its associated risks among adolescents and young adults in South Africa. A cross-sectional study was conducted to assess HPV infection and associated risks knowledge level among learners attending high schools in the Eastern Cape Province of South Africa. Learners (females and males) attending five selected schools in the Eastern Cape Province of South Africa participated. The intervention included knowledge pre-assessment, education through structured lecture, and post-education assessment. Self-administered questionnaires were used in both pre and post-intervention assessments. There were 2652 learners, who participated, with a median age of 18 years (IQR: 16-19). Female participants constituted 53.58% (1421/2652), and male participants were 46.42% (1231/2652). Before education intervention, only 4.08% (107/2623) of learners ever heard about HPV and 3.31% (87/2626) about HPV vaccination. Only 9.36% (247/2638) and 9.34% (246/2635) knew that HPV infection is sexually transmitted and associated with cervical cancer development, respectively. After education intervention, knowledge about HPV among learners increased significantly (p < 0.001). In post-education assessment, female high school learners were 66% more likely to acquire HPV knowledge than males (OR, 1.66; 95% CI, 1.40-1.97; p < 0.0001). Exposure to an educational intervention significantly increased learners' knowledge levels. The increasing burden of cervical cancer and other HPV-associated cancers are public health problems of concern. Therefore, the evaluation of educational interventions for increasing knowledge on HPV-associated diseases is necessary for low-resource settings with a high burden of cervical cancer.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adolescente , Adulto Jovem , Humanos , Masculino , Feminino , Adulto , Papillomavirus Humano , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , África do Sul , Estudos Transversais , Instituições Acadêmicas , Inquéritos e Questionários , Vacinas contra Papillomavirus/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde
8.
Front Reprod Health ; 4: 887736, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36303664

RESUMO

Background: Genital human papillomavirus (HPV) is the most common sexually transmitted virus in most populations globally. Adolescent girls and young women (AGYW) remain a key population group at risk for HPV infection. However, the risk factors of HPV infection among AGYW, especially in sub-Saharan Africa, are a subject of little investigation in published literature. Here, we investigated the factors associated with HPV infection among unvaccinated South African AGYW with a high HPV burden (prevalence: 76.1%). Methods: We retrospectively recruited 213 AGYW learners (aged 15-25 years) from a previous cross-sectional study, the HPV Education Intervention Study, conducted in the Eastern Cape, South Africa. Sexually transmitted infections (STIs), bacterial pathobionts, genital ulcers (due to infectious causes), candidiasis, and bacterial vaginosis (BV) in the self-collected vaginal specimens were determined using the Allplex™ Panel Assays. Statistical analyses were performed using STATA v16.1. Continuous and categorical variables were computed by t-test /Wilcoxon rank-sum test and Chi-square/Fisher's exact tests, respectively. Logistic regression was used to determine the univariable predictors of HPV infection. Results: The overall detection rate of any viral STI, bacterial STI, pathobiont, genital ulcer, candidiasis, and BV among the AGYW was 75.0, 34.4, 90.7, 14.4, 26.9, and 43.6%, respectively. The main factors associated with HPV infection were alcohol consumption (p = 0.005), infection with any and multiple Candida species (p = 0.011 and 0.006, respectively), Candida albicans infection (p = 0.010), Ureaplasma urealyticum pathobiont infection (p = 0.044), BV-associated bacteria (specifically Atopobium vaginae: p = 0.039, BV-associated bacteria 2: p = 0.021, Gardnerella vaginalis: p = 0.021, Megasphaera type 1: p = 0.037), and BV (p = 0.011). Conclusions: Our study, albeit not necessarily generalizable, found social behavior as well as specific vaginal microbes as correlates of HPV infection among AGYW in South Africa. There is a need to investigate HPV epidemiology in other AGYW populations. The factors associated with genital HPV infection among AGYW burdened with HPV infection necessitate the need to formulate and implement population-specific public health strategies for creating HPV awareness and reducing its risk.

9.
Biotechnol Bioeng ; 119(10): 2919-2937, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35781691

RESUMO

Heterologous glycoprotein production relies on host glycosylation-dependent folding. When the biosynthetic machinery differs from the usual expression host, there is scope to remodel the assembly pathway to enhance glycoprotein production. Here we explore the integration of chaperone coexpression with glyco-engineering to improve the production of a model HIV-1 envelope antigen. Calreticulin was coexpressed to support protein folding together with Leishmania major STT3D oligosaccharyltransferase, to improve glycan occupancy, RNA interference to suppress the formation of truncated glycans, and Nicotiana benthamiana plants lacking α1,3-fucosyltransferase and ß1,2-xylosyltransferase was used as an expression host to prevent plant-specific complex N-glycans forming. This approach reduced the formation of undesired aggregates, which predominated in the absence of glyco-engineering. The resulting antigen also exhibited increased glycan occupancy, albeit to a slightly lower level than the equivalent mammalian cell-produced protein. The antigen was decorated almost exclusively with oligomannose glycans, which were less processed compared with the mammalian protein. Immunized rabbits developed comparable immune responses to the plant-produced and mammalian cell-derived antigens, including the induction of autologous neutralizing antibodies when the proteins were used to boost DNA and modified vaccinia Ankara virus-vectored vaccines. This study demonstrates that engineering glycosylation-directed folding offers a promising route to enhance the production of complex viral glycoproteins in plants.


Assuntos
Anticorpos Neutralizantes , Infecções por HIV , Animais , Antígenos Virais/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Anticorpos Anti-HIV , Mamíferos/metabolismo , Polissacarídeos/metabolismo , Coelhos
10.
J Gen Virol ; 103(5)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35594121

RESUMO

In vivo nucleic expression technologies using DNA or mRNA offer several advantages for recombinant gene expression. Their inherent ability to generate natively expressed recombinant proteins and antigens allows these technologies to mimic foreign gene expression without infection. Furthermore, foreign nucleic acid fragments have an inherent ability to act as natural immune adjuvants and stimulate innate pathogen- and DNA damage-associated receptors that are responsible for activating pathogen-associated molecular pattern (PAMP) and DNA damage-associated molecular pattern (DAMP) signalling pathways. This makes nucleic-acid-based expression technologies attractive for a wide range of vaccine and oncolytic immunotherapeutic uses. Recently, RNA vaccines have demonstrated their efficacy in generating strong humoral and cellular immune responses for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). DNA vaccines, which are more stable and easier to manufacture, generate similar immune responses to RNA, but typically exhibit lower immunogenicity. Here we report on a novel method of constructing self-amplifying DNA expression vectors that have the potential to amplify and enhance gene/antigen expression at a cellular level by increasing per cell gene copy numbers, boost genomic adjuvating effects and mitigate through replication many of the problems faced by non-replicating vectors such as degradation, methylation and gene silencing. These vectors employ a viral origin rolling circle replication cycle in mammalian host cells that amplifies the vector and gene of interest (GOI) copy number, maintaining themselves as nuclear episomes. We show that these vectors maintain persistently elevated GOI expression levels at the cellular level and induce morphological cellular alterations synonymous with increased cellular stress.


Assuntos
COVID-19 , Circovirus , Vacinas de DNA , Animais , Circovirus/genética , Vetores Genéticos/genética , Mamíferos , SARS-CoV-2 , Vacinas de DNA/genética
11.
PLoS One ; 17(3): e0264498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35263376

RESUMO

Human papillomavirus (HPV) prevalence and genotype distribution data is important for HPV vaccine monitoring. This study investigated the prevalence and distribution of HPV genotypes in cervical lesions of unvaccinated women referred to Nelson Mandela Academic Hospital Gynaecology Department due to different abnormal cervical conditions. A total of 459 women referred to the Nelson Mandela Academic Hospital Gynaecology department were recruited. When the cervical biopsy was collected for histopathology, an adjacent biopsy was provided for HPV detection. Roche Linear Array HPV genotyping assay that detects 37 HPV genotypes was used to detect HPV infection in cervical biopsies. HPV infection was detected in 84.2% (383/455) of participants. The six most dominant HPV types were HPV-16 (34.7%), followed by HPV-35 (17.4%), HPV-58 (12.1%), HPV-45 (11.6%), HPV-18 (11.4%) and HPV-52 (9.7%). HPV-35 was the third most dominant type among women with cervical intraepithelial lesion (CIN)-2 (12.6%; single infection: 5.7% and multiple infection: 6.9%), the second most dominant type among women with CIN3 (22.2%; single infection: 8.0% and multiple infection: 14.2%); and the fourth most dominant type among women with cervical cancer (12.5%; single infection: 7.1% and multiple infection: 5.4%). A proportion of 41.1% (187/455) was positive for HPV types targeted by the Cervarix®, 42.4% (193/455) by Gardasil®4, and 66.6% (303/455) by Gardasil®9. There was a statistically significant increase when the prevalence of women infected with HPV-35 only or with other HPV types other than Gardasil®9 types was included to those infected with Gardasil®9 HPV types (66.6%, 303/455 increase to 76.0%, 346/455, p = 0.002). High HPV-35 prevalence in this population, especially among women with CIN3 warrants attention since it is not included in current commercially available HPV vaccines.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Alphapapillomavirus/genética , Atenção , Feminino , Genótipo , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Humanos , Masculino , Papillomaviridae/genética , Prevalência , África do Sul/epidemiologia , Neoplasias do Colo do Útero/patologia
12.
Vaccines (Basel) ; 10(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35214669

RESUMO

The current method to protect cattle against East Coast Fever (ECF) involves the use of live Theileria parva sporozoites. Although this provides immunity, using live parasites has many disadvantages, such as contributing to the spread of ECF. Subunit vaccines based on the sporozoite surface protein p67 have been investigated as a replacement for the current method. In this study, two DNA vaccines expressing recombinant forms of p67 designed to display on retrovirus-like particles were constructed with the aim of improving immunogenicity. The native leader sequence was replaced with the human tissue plasminogen activator leader in both vaccines. The full-length p67 gene was included in the first DNA vaccine (p67); in the second, the transmembrane domain and cytoplasmic tail were replaced with those of an influenza A virus hemagglutinin 5 (p67HA). Immunofluorescent staining of fixed and live transfected mammalian cells showed that both p67 and p67HA were successfully expressed, and p67HA localised on the cell surface. Furthermore, p67HA was displayed on the surface of both bovine leukaemia virus (BLV) Gag and HIV-1 Gag virus-like particles (VLPs) made in the same cells. Mice vaccinated with DNA vaccines expressing p67 and p67HA alone, or p67HA with BLV or HIV-1 Gag, developed high titres of p67 and BLV Gag-binding antibodies. Here we show that it is possible to integrate a form of p67 containing all known antigenic domains into VLPs. This p67HA-VLP combination has the potential to be incorporated into a vaccine against ECF, as a DNA vaccine or as other vaccine platforms.

13.
Front Plant Sci ; 12: 709344, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367227

RESUMO

There is an urgent need to establish large scale biopharmaceutical manufacturing capacity in Africa where the infrastructure for biologics production is severely limited. Molecular farming, whereby pharmaceuticals are produced in plants, offers a cheaper alternative to mainstream expression platforms, and is amenable to rapid large-scale production. However, there are several differences along the plant protein secretory pathway compared to mammalian systems, which constrain the production of complex pharmaceuticals. Viral envelope glycoproteins are important targets for immunization, yet in some cases they accumulate poorly in plants and may not be properly processed. Whilst the co-expression of human chaperones and furin proteases has shown promise, it is presently unclear how plant-specific differences in glycosylation impact the production of these proteins. In many cases it may be necessary to reproduce features of their native glycosylation to produce immunologically relevant vaccines, given that glycosylation is central to the folding and immunogenicity of these antigens. Building on previous work, we transiently expressed model glycoproteins from HIV and Marburg virus in Nicotiana benthamiana and mammalian cells. The proteins were purified and their site-specific glycosylation was determined by mass-spectrometry. Both glycoproteins yielded increased amounts of protein aggregates when produced in plants compared to the equivalent mammalian cell-derived proteins. The glycosylation profiles of the plant-produced glycoproteins were distinct from the mammalian cell produced proteins: they displayed lower levels of glycan occupancy, reduced complex glycans and large amounts of paucimannosidic structures. The elucidation of the site-specific glycosylation of viral glycoproteins produced in N. benthamiana is an important step toward producing heterologous viral glycoproteins in plants with authentic human-like glycosylation.

14.
PLoS One ; 16(6): e0253074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34143816

RESUMO

As part of the human papillomavirus (HPV) vaccination strategy in South Africa, it is essential to have information on HPV prevalence, and HPV types distribution among the unvaccinated population. Information on the prevalence of HPV and the distribution of HPV types in adolescents and young women in South Africa's Eastern Cape Province is minimal. Therefore, this study investigates the prevalence, distribution of HPV types, and factors associated with HPV infection amongst unvaccinated female learners. A sample composed of 213 sexually active female learners attending high schools in the Eastern Cape Province of South Africa; median age 18 years, who provided self-collected vaginal specimens. Roche Linear Array HPV genotyping assay that detects 37 HPV genotypes was used to detect HPV infection. HPV infection was detected in 76.06% (162/213) of participants. Of these 14.55% (31/213) were positive for HPV types targeted by the Cervarix® HPV vaccine (HPV-16 and/or 18), 20.66% (44/213) by Gardasil®4 (HPV-6, -11, -16 and/or -18) and 37.09% (79/213) by Gardasil®9 (HPV-6, -11, -16, -18, -31, -33, -45, -52 and/or -58). HPV-35, commonly detected in cervical cancer cases among women of African ancestry, was frequently detected (9.40%). Participants who reported to have ever consumed alcohol had a significantly higher risk of HPV infection (OR: 2.91, 95% CI: 1.38-6.11, p = 0.005). High HPV prevalence was observed among participants. The high prevalence of HPV types targeted by the Gardasil®9 vaccine encourages the introduction of the Gardasil®9 vaccine. Data from this study will inform both vaccination campaigns and monitor the impact on HPV types after vaccination.


Assuntos
Alphapapillomavirus/classificação , Infecções por Papillomavirus/epidemiologia , Estudantes/estatística & dados numéricos , Adolescente , Alphapapillomavirus/genética , Alphapapillomavirus/isolamento & purificação , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Humanos , Vacinação em Massa , Infecções por Papillomavirus/prevenção & controle , Vigilância da População , Prevalência , Medição de Risco , Comportamento Sexual , África do Sul/epidemiologia , Adulto Jovem
15.
PLoS One ; 16(6): e0253218, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34143825

RESUMO

Mounting evidence suggests that Lactobacillus species may not necessarily be the sine qua non of healthy cervicovaginal microbiota (CVM), especially among reproductive-age African women. A majority of African women have high-diversity non-Lactobacillus-dominated CVM whose bacterial functions remain poorly characterized. Functional profiling of the CVM is vital for investigating human host-microbiota interactions in health and disease. Here, we investigated the functional potential of L. iners-dominated and high-diversity non-Lactobacillus-dominated CVM of 75 African women with and without bacterial vaginosis (BV) and high-risk human papillomavirus (HR-HPV) infection. Functional contents were predicted using PICRUSt. Microbial taxonomic diversity, BV, and HR-HPV infection statuses were correlated with the inferred functional composition of the CVM. Differentially abundant inferred functional categories were identified using linear discriminant analysis (LDA) effect size (LEfSe) (p-value <0.05 and logarithmic LDA score >2.0). Of the 75 women, 56 (74.7%), 35 (46.7%), and 29 (38.7%) had high-diversity non-Lactobacillus-dominated CVM, BV, and HR-HPV infection, respectively. Alpha diversity of the inferred functional contents (as measured by Shannon diversity index) was significantly higher in women with high-diversity non-Lactobacillus-dominated CVM and BV than their respective counterparts (H statistic ≥11.5, q-value <0.001). Ordination of the predicted functional metagenome content (using Bray-Curtis distances) showed that the samples segregated according to the extent of microbial taxonomic diversity and BV (pseudo-F statistic ≥19.6, q-value = 0.001) but not HR-HPV status (pseudo-F statistic = 1.7, q-value = 0.159). LEfSe analysis of the inferred functional categories revealed that transport systems (including ABC transporters) and transcription factors were enriched in high-diversity CVM. Interestingly, transcription factors and sporulation functional categories were uniquely associated with high-diversity CVM, BV, and HR-HPV infection. Our predictive functional analysis reveals features unique to high-diversity CVM, BV and HR-HPV infections. Such features may represent important biomarkers of BV and HR-HPV infection. Our findings require proof-of-concept functional studies to examine the relevance of these potential biomarkers in women's reproductive health and disease.


Assuntos
Colo do Útero/microbiologia , Microbiota/fisiologia , Infecções por Papillomavirus/microbiologia , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Adolescente , Adulto , Feminino , Humanos , Lactobacillus/isolamento & purificação , Adulto Jovem
16.
Viruses ; 13(2)2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670231

RESUMO

South African women have a high rate of cervical cancer cases, but there are limited data on human papillomavirus (HPV) genotypes in cervical intraepithelial neoplasia (CIN) in the Eastern Cape province, South Africa. A total of 193 cervical specimens with confirmed CIN from women aged 18 years or older, recruited from a referral hospital, were tested for HPV infection. The cervical specimens, smeared onto FTA cards, were screened for 36 HPV types using an HPV direct flow kit. HPV prevalence was 93.5% (43/46) in CIN2 and 96.6% (142/147) in CIN3. HIV-positive women had a significantly higher HPV prevalence than HIV-negative women (98.0% vs. 89.1%, p = 0.012). The prevalence of multiple types was significantly higher in HIV-positive than HIV-negative women (p = 0.034). The frequently detected genotypes were HPV35 (23.9%), HPV58 (23.9%), HPV45 (19.6%), and HPV16 (17.3%) in CIN2 cases, while in CIN3, HPV35 (22.5%), HPV16 (21.8%), HPV33 (15.6%), and HPV58 (14.3%) were the most common identified HPV types, independent of HIV status. The prevalence of HPV types targeted by the nonavalent HPV vaccine was 60.9% and 68.7% among women with CIN2 and CIN3, respectively, indicating that vaccination would have an impact both in HIV-negative and HIV-positive South African women, although it will not provide full protection in preventing HPV infection and cervical cancer lesions.


Assuntos
Infecções por HIV/epidemiologia , Papillomaviridae/classificação , Infecções por Papillomavirus/epidemiologia , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Colo do Útero/patologia , Colo do Útero/virologia , Feminino , Soronegatividade para HIV , Soropositividade para HIV , Humanos , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Prevalência , África do Sul/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/prevenção & controle
17.
PeerJ ; 9: e10793, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717675

RESUMO

BACKGROUND: South African women of reproductive age have a high burden of sexually transmitted infections (STIs), including human papillomavirus (HPV) infection. However, there is limited information on the prevalence of sexually transmitted pathogens in women from rural Eastern Cape Province, South Africa. The study aims at determining the prevalence of sexually transmitted pathogens and co-infection with high-risk (HR) HPV among women from rural Eastern Cape Province, South Africa. METHODS: A total of 205 cervical specimens were collected from women aged ≥ 30 years from a rural community-based clinic. The samples were tested for a panel of pathogenic STIs [Chlamydia trachomatis (serovars A-K & L1-L3), Haemophilus ducreyi, Herpes Simplex Virus (Types 1 & 2), Neisseria gonorrhoeae, Treponema pallidum, Trichomonas vaginalis (TV), and pathobionts [Mycoplasma genitalium (MG), Mycoplasma hominis (MH) and Ureaplasma spp. (UP)] using a multiplex PCR STD direct flow chip assay through a manual Hybrispot platform (Master Diagnostica, Granada, Spain). HR-HPV detection was performed by Hybrid Capture-2 assay. RESULTS: High-risk HPV prevalence was 32.2% (66/205) and HIV-1 prevalence was 38.5% (79/205). The overall prevalence of six pathogenic STIs was 22.9% (47/205), with TV having the highest prevalence (15.6%; 32/205). UP (70.2%, 144/205) and MH (36.6%, 75/205) were the most frequently detected pathobionts. Co-infection with ≥ 2 pathogens pathobionts was observed among 52.7% (108/205) participants. Of the six pathogenic STIs, three participants had more than one STI (1.46%) with the presence of MH and UP. HSV-2 (OR: 4.17, CI [1.184-14.690]) and HIV infection (OR: 2.11, CI [1.145-3.873]) were independent STIs associated with HR-HPV infection. CONCLUSIONS: The high prevalence of pathogenic STIs underscores the need to improve syndromic management policy by implementing effective strategies of prevention, screening tests, and management. HSV-2 and HIV positive remain strongly associated with HR-HPV infection.

18.
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
19.
PLoS One ; 15(11): e0241781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170891

RESUMO

Human papillomavirus (HPV) testing on vaginal self-collected and cervical clinician-collected specimens shows comparable performance. Self-sampling on FTA cards is suitable for women residing in rural settings or not attending regular screening and increases participation rate in the cervical cancer screening programme. We aimed to investigate and compare high-risk (HR)-HPV prevalence in clinician-collected and self-collected genital specimens as well as two different HPV tests on the clinician collected samples. A total of 737 women were recruited from two sites, a community health clinic (n = 413) and a referral clinic (n = 324) in the Eastern Cape Province. Cervical clinician-collected (FTA cards and Digene transport medium) and vaginal self-collected specimens were tested for HR-HPV using the hpVIR assay (FTA cards) and Hybrid Capture-2 (Digene transport medium). There was no significant difference in HR-HPV positivity between clinician-collected and self-collected specimens among women from the community-based clinic (26.4% vs 27.9%, p = 0.601) or the referral clinic (83.6% vs 79.9%, p = 0.222). HPV16, HPV35, and HPV33/52/58 group were the most frequently detected genotypes at both study sites. Self-sampling for HPV testing received a high positive response of acceptance (77.2% in the community-based clinic and 83.0% in referral clinic). The overall agreement between hpVIR assay and HC-2 was 87.7% (k = 0.754). The study found good agreement between clinician-collected and self-collected genital specimens. Self-collection can have a positive impact on a cervical screening program in South Africa by increasing coverage of women in rural areas, in particular those unable to visit the clinics and women attending clinics where cytology-based programs are not functioning effectively.


Assuntos
Alphapapillomavirus/patogenicidade , Colo do Útero/virologia , Adolescente , Adulto , Alphapapillomavirus/genética , Estudos Transversais , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , África do Sul , Neoplasias do Colo do Útero/virologia , Adulto Jovem
20.
Viruses ; 12(8)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824449

RESUMO

Bovine leukaemia virus (BLV) causes chronic lymphoproliferative disorder and fatal lymphosarcoma in cattle, leading to significant economic losses in the beef and dairy industries. BLV is endemic globally and eleven genotypes have been identified. To date, only Zambian isolates have been genotyped from Africa. Although high BLV prevalence has been reported in South Africa, there has been no molecular characterisation of South African BLV isolates. To characterise BLV isolates in South Africa for the first time, we investigated the phylogenetic relationships and compared the genetic variability of eight South African BLV isolates with BLV isolates representing the eleven known genotypes from different geographical regions worldwide. Phylogenetic analyses based on full-length and partial env sequences as well as full-length gag sequences revealed that at least two genotypes, genotypes 1 (G1) and 4 (G4), are present in cattle in South Africa, which is consistent with studies from Zambia. However, our analysis revealed that the G1 South African isolate is more similar to other G1 isolates than the G1 Zambian isolates whereas, the G4 South African isolates are more divergent from other G4 isolates but closely related to the G4 Zambian isolate. Lastly, amino acid sequence alignment identified genotype-specific as well as novel amino acid substitutions in the South African isolates. The detection of two genotypes (G1 and G4) in southern Africa highlights the urgent need for disease management and the development of an efficacious vaccine against local strains.


Assuntos
Leucose Enzoótica Bovina/virologia , Variação Genética , Vírus da Leucemia Bovina/classificação , Filogenia , Substituição de Aminoácidos , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Indústria de Laticínios , Feminino , Genótipo , Análise de Sequência de DNA , África do Sul , Zâmbia
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