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1.
Viruses ; 16(1)2024 Jan 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
2.
PLoS One ; 18(11): e0294285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37948399

RESUMO

BACKGROUND: South Africa is among the countries with the highest prevalence of sexually transmitted infections (STIs), including Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). In 2017, there were an estimated 6 million new CT, 4.5 million NG and 71 000 Treponema pallidum infections among South African men and women of reproductive age. METHODS: We evaluated STI prevalence and incidence and associated risk factors in 162 women aged 18-33 years old, residing in eThekwini and Tshwane, South Africa who were part of the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial. Women were randomised to use depot medroxyprogesterone acetate (n = 53), copper intrauterine device (n = 51), or levonorgestrel (n = 58) implant. Lateral vaginal wall swab samples were collected prior to contraceptive initiation and at months one and three following contraceptive initiation for STI testing. RESULTS: There were no significant differences in STI incidence and prevalence across contraceptive groups. At baseline, 40% had active STIs (CT, NG, Trichomonas vaginalis (TV), Mycoplasma genitalium (MG) or herpes simplex virus-2 shedding across all age groups- 18-21 years (46%), 22-25 years (42%) and 26-33 years (29%). The incidence of STIs during follow-up was exceptionally high (107.9/100 women-years [wy]), with younger women (18-21 years) more likely to acquire CT (75.9/100 wy) compared to 26-33 year olds (17.4/100 wy; p = 0.049). TV incidence was higher in the 26-33 year old group (82.7/100 wy) compared to the 18-21 year olds (8.4/100 wy; p = 0.01). CONCLUSIONS: Although the study participants received extensive counselling on the importance of condom use, this study highlights the high prevalence and incidence of STIs in South African women, especially amongst young women, emphasising the need for better STI screening and management strategies.


Assuntos
Infecções por Chlamydia , Infecções por HIV , Infecções Sexualmente Transmissíveis , Trichomonas vaginalis , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , África do Sul/epidemiologia , Anticoncepcionais , Prevalência , Incidência , Infecções Sexualmente Transmissíveis/prevenção & controle , Chlamydia trachomatis , Neisseria gonorrhoeae , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/diagnóstico
3.
Viruses ; 15(7)2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37515096

RESUMO

The SARS-CoV-2 pandemic demonstrated the need for potent and broad-spectrum vaccines. This study reports the development and testing of a lumpy skin disease virus (LSDV)-vectored vaccine against SARS-CoV-2, utilizing stabilized spike and conserved nucleocapsid proteins as antigens to develop robust immunogenicity. Construction of the vaccine (LSDV-SARS2-S,N) was confirmed by polymerase chain reaction (PCR) amplification and sequencing. In vitro characterization confirmed that cells infected with LSDV-SARS2-S,N expressed SARS-CoV-2 spike and nucleocapsid protein. In BALB/c mice, the vaccine elicited high magnitude IFN-γ ELISpot responses (spike: 2808 SFU/106 splenocytes) and neutralizing antibodies (ID50 = 6552). Testing in hamsters, which emulate human COVID-19 disease progression, showed the development of high titers of neutralizing antibodies against the Wuhan and Delta SARS-CoV-2 variants (Wuhan ID50 = 2905; Delta ID50 = 4648). Additionally, hamsters vaccinated with LSDV-SARS2-S,N displayed significantly less weight loss, lung damage, and reduced viral RNA copies following SARS-CoV-2 infection with the Delta variant as compared to controls, demonstrating protection against disease. These data demonstrate that LSDV-vectored vaccines display promise as an effective SARS-CoV-2 vaccine and as a potential vaccine platform for communicable diseases in humans and animals. Further efficacy testing and immune response analysis, particularly in non-human primates, are warranted.


Assuntos
COVID-19 , Vírus da Doença Nodular Cutânea , Vacinas , Animais , Cricetinae , Bovinos , Camundongos , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Endogâmicos BALB C , Proteínas do Nucleocapsídeo , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética
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.
Vaccines (Basel) ; 11(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36992162

RESUMO

Lumpy skin disease virus (LSDV) is a member of the Capripoxvirus genus, mainly infecting cattle and buffalo, which until relatively recently was only endemic in parts of Africa and then spread to the Middle East and lately Europe and Asia. Lumpy skin disease (LSD) is a notifiable disease with a serious impact on the beef industry as it causes mortality of up to 10% and has impacts on milk and meat production, as well as fertility. The close serological relationship between LSDV, goat poxvirus (GTPV) and sheep poxvirus (SPPV) has led to live attenuated GTPV and SPPV vaccines being used to protect against LSD in some countries. There is evidence that the SPPV vaccine does not protect from LSD as well as the GTPV and LSDV vaccines. One of the LSD vaccines used in Eastern Europe was found to be a combination of different Capripoxviruses, and a series of recombination events in the manufacturing process resulted in cattle being vaccinated with a range of recombinant LSDVs resulting in virulent LSDV which spread throughout Asia. It is likely that LSD will become endemic throughout Asia as it will be very challenging to control the spread of the virus without widespread vaccination.

7.
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.

8.
Vaccines (Basel) ; 11(2)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36851255

RESUMO

The combination of mosaic Gag and CAP256 envelope in an HIV vaccine regimen comprising DNA prime and modified vaccinia Ankara (MVA) boost followed by protein boost has previously been shown to generate robust autologous Tier 2 neutralizing antibodies (nAbs) in rabbits. Further refinements of this strategy have been investigated to improve antibody responses. The delivery of both DNA and recombinant MVA vaccines with a needle-free device was compared to delivery by injection, and the effect of formulating the DNA vaccine with adjuvant CpG ODN 1826 was determined. The Pharmajet Stratis® needle-free injection device (PharmaJet, Golden, CO, USA) improved binding antibody responses to the DNA vaccine as well as both binding and neutralizing antibody responses to the MVA vaccines. Formulation of the DNA vaccines with CpG adjuvant further improved the antibody responses. A shortened vaccination regimen of a single DNA inoculation followed by a single MVA inoculation did not elicit Tier 1B nor Tier 2 neutralization responses as produced by the two DNA, followed by two MVA vaccination regimen. This study showed the immunogenicity of HIV DNA and MVA vaccines administered in a DDMM regimen could be improved using the PharmaJet Stratis needle-free injection device and formulation of the DNA vaccines with CpG adjuvant.

9.
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
10.
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.

11.
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
12.
Nanotechnology ; 33(48)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35882111

RESUMO

Two-component self-assembling virus-like particles (VLPs) are promising scaffolds for achieving high-density display of HIV-1 envelope (gp140) trimers, which can improve the induction of neutralising antibodies (NAbs). In this study gp140 was displayed on the surface of VLPs formed by the AP205 phage coat protein. The CAP256 SU gp140 antigen was selected as the patient who this virus was isolated from developed broadly neutralising antibodies (bNAbs) shortly after superinfection with this virus. The CAP256 SU envelope is also sensitive to several bNAbs and has shown enhanced reactivity for certain bNAb precursors. A fusion protein comprising the HIV-1 CAP256 SU gp140 and the SpyTag (ST) (gp140-ST) was produced in HEK293 cells, and trimers were purified to homogeneity using gel filtration. SpyCatcher (SC)-AP205 VLPs were produced inEscherichia coliand purified by ultracentrifugation. The gp140-ST trimers and the SC-AP205 VLPs were mixed in varying molar ratios to generate VLPs displaying the glycoprotein (AP205-gp140-ST particles). Dynamic light scattering, negative stain electron microscopy and 2D classification indicated that gp140-ST was successfully bound to the VLPs, although not all potential binding sites were occupied. The immunogenicity of the coupled VLPs was evaluated in a pilot study in rabbits. One group was injected four times with coupled VLPs, and the second group was primed with DNA vaccines expressing Env and a mosaic Gag, followed by modified vaccinia Ankara expressing the same antigens. The animals were then boosted twice with coupled VLPs. Encouragingly, gp140-ST displayed on SC-AP205 VLPs was an effective boost to heterologously primed rabbits, leading to induction of autologous Tier 2 neutralising antibodies in 2/5 rabbits. However, four inoculations of coupled VLPs alone failed to elicit any Tier 2 antibodies. These results demonstrate that the native-like structure of HIV-1 envelope trimers and selection of a geometrically-suitable nanoparticle scaffold to achieve a high-density display of the trimers are important considerations that could improve the effect of nanoparticle-displayed gp140.


Assuntos
HIV-1 , Nanopartículas , Vacinas , Animais , Anticorpos Amplamente Neutralizantes , Células HEK293 , Humanos , Projetos Piloto , Coelhos , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
13.
Microbiol Spectr ; 10(3): e0222921, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35647888

RESUMO

Bacterial vaginosis (BV) is a common polymicrobial vaginal disorder that is associated with sexually transmitted infections (STIs), including HIV. Several studies have utilized broad-range 16S rRNA gene PCR assays with sequence analysis to characterize cervicovaginal bacterial communities of women with healthy and diseased conditions. With the high burden of BV and STIs among African women, there is a need for targeted PCR assays that can rapidly determine the true epidemiological profile of key cervical microbes, including BV-associated bacteria, and a need to explore the utility of such assays for microbiological diagnosis of BV. Here, we used a taxon-directed 16S rRNA gene quantitative PCR (qPCR) assay to examine the prevalences and determinants of specific cervical microbes among African women with and without HIV infection. Cervical samples were collected using a cytobrush from 162 women (aged ≥30 years) attending a community-based clinic in Eastern Cape, South Africa. The samples were screened for specific microbes (i.e., STIs, emerging sexually transmitted pathogens [pathobionts], and BV-associated bacteria) using a customized bacterial vaginosis microbial DNA qPCR array. Statistical analyses were performed using GraphPad Prism v6.01. Chi-square/Fisher's exact tests were used to evaluate the determinants associated with specific cervical microbes. Only 145 women had any detectable microbes and were included in the analysis. Lactobacillus iners (62.8%) and specific BV-associated bacteria, namely, Gardnerella vaginalis (58.6%), Atopobium vaginae (40.7%), and the pathobiont Ureaplasma parvum (37.9%), were the most prevalent microbes. Hierarchical clustering analysis revealed that 42.8% of the women (62/145) had a diverse array of heterogeneously distributed bacteria typically linked to BV. Women with detectable Lactobacillus species, specifically Lactobacillus crispatus and Lactobacillus jensenii, and to a lesser extent L. iners, had very low prevalence of BV-associated bacteria. Although the cumulative burden of STIs/pathobionts was 62.8%, Chlamydia trachomatis (3.4%), Neisseria gonorrhoeae (4.8%), and Trichomonas vaginalis (4.8%) were detected at low rates. HIV infection was associated with the presence of STIs/pathobionts (P = 0.022) and L. iners (P = 0.003). Prevalent STIs/pathobionts were associated with having multiple partners in the past 12 months (n ≥ 2, P = 0.015), high number of lifetime sexual partners (n ≥ 3, P = 0.007), vaginal sex in the past month (P = 0.010), and decreasing age of women (P = 0.005). C. trachomatis was associated with increasing age among HIV-positive women (P = 0.016). The pathobiont Ureaplasma urealyticum was inversely associated with age of women in the whole cohort (P = 0.018). The overall prevalence of STIs/pathobionts was high and was associated with HIV infection and sexual behavior. Our study helps us to understand the epidemiological trend of STIs and pathobionts and highlights the need to understand the impact of sexual networks on STI and pathobiont transmission and prevention among women in an African setting. IMPORTANCE Bacterial vaginosis (BV), whose etiology remains a matter of controversy, is a common vaginal disorder among reproductive-age women and can increase the risk for sexually transmitted infections (STIs). African women bear a disproportionately high burden of STIs and BV. Using a targeted quantitative PCR (qPCR) assay, a customized bacterial vaginosis microbial DNA qPCR array, we examined the prevalences and determinants of key cervical microbes, including BV-associated bacteria and emerging sexually transmitted pathogens (pathobionts) among women of African descent aged between 30 and 75 years. High-risk behaviors were associated with a higher prevalence of STIs/pathobionts, suggesting the need to better understand the influence of sexual networks on STI and pathobiont transmission and prevention among women. Our molecular assay is important in the surveillance of BV-associated bacteria, pathobionts, and STIs as well as diagnostic microbiology of BV. Furthermore, our research contributes to a better understanding of the epidemiology of STIs and pathobionts in Africa.


Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Vaginose Bacteriana , Adulto , Idoso , Chlamydia trachomatis , DNA , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Infecções Sexualmente Transmissíveis/complicações , Infecções Sexualmente Transmissíveis/epidemiologia , África do Sul/epidemiologia , Vagina/microbiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/microbiologia
14.
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
15.
Am J Reprod Immunol ; 88(2): e13542, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35394678

RESUMO

PROBLEM: Data on the effects of contraceptives on female genital tract (FGT) immune mediators are inconsistent, possibly in part due to pre-existing conditions that influence immune mediator changes in response to contraceptive initiation. METHODS: This study included 161 South African women randomised to injectable depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (IUD), or levonorgestrel (LNG) implant in the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial. We measured thirteen cytokines and antimicrobial peptides previously associated with HIV acquisition in vaginal swabs using Luminex and ELISA, before, and at 1 and 3 months after contraceptive initiation. Women were grouped according to an overall baseline inflammatory profile. We evaluated modification of the relationships between contraceptives and immune mediators by baseline inflammation, demographic, and clinical factors. RESULTS: Overall, LNG implant and copper IUD initiation were associated with increases in inflammatory cytokines, while no changes were observed following DMPA-IM initiation. However, when stratifying by baseline inflammatory profile, women with low baseline inflammation in all groups experienced significant increases in inflammatory cytokines, while those with a high baseline inflammatory profile experienced no change or decreases in inflammatory cytokines. CONCLUSION: We conclude that pre-contraceptive initiation immune profile modifies the effect of contraceptives on the FGT innate immune response.


Assuntos
Anticoncepcionais Femininos , Infecções por HIV , Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Femininos/farmacologia , Citocinas , Feminino , Genitália , Infecções por HIV/epidemiologia , Humanos , Imunidade Inata , Inflamação , Dispositivos Intrauterinos de Cobre/efeitos adversos , Levanogestrel/efeitos adversos , Levanogestrel/farmacologia , Acetato de Medroxiprogesterona/efeitos adversos , Acetato de Medroxiprogesterona/farmacologia
16.
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
17.
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.

18.
Viruses ; 14(2)2022 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-35216023

RESUMO

The female reproductive tract (FRT) microbiome plays a vital role in maintaining vaginal health. Viruses are key regulators of other microbial ecosystems, but little is known about how the FRT viruses (virome), particularly bacteriophages that comprise the phageome, impact FRT health and dysbiosis. We hypothesize that bacterial vaginosis (BV) is associated with altered FRT phageome diversity, transkingdom interplay, and bacteriophage discriminate taxa. Here, we conducted a retrospective, longitudinal analysis of vaginal swabs collected from 54 BV-positive and 46 BV-negative South African women. Bacteriome analysis revealed samples clustered into five distinct bacterial community groups (CGs), and further, bacterial alpha diversity was significantly associated with BV. Virome analysis on a subset of baseline samples showed FRT bacteriophages clustering into novel viral state types (VSTs), a viral community clustering system based on virome composition and abundance. Distinct BV bacteriophage signatures included increased alpha diversity along with discriminant Bacillus, Burkholderia, and Escherichia bacteriophages. Bacteriophage-bacteria transkingdom associations were also identified between Bacillus and Burkholderia viruses and BV-associated bacteria, providing key insights for future studies elucidating the transkingdom interactions driving BV-associated microbiome perturbations. In this cohort, bacteriophage-bacterial associations suggest complex interactions, which may play a role in the establishment and maintenance of BV.


Assuntos
Bacteriófagos/classificação , Vagina/microbiologia , Vagina/virologia , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/virologia , Adolescente , Disbiose , Feminino , Infecções por HIV/complicações , Humanos , Microbiota , Estudos Retrospectivos , África do Sul , Viroma/imunologia , Adulto Jovem
19.
Vaccines (Basel) ; 9(11)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34835146

RESUMO

Dual vaccines (n = 6) against both lumpy skin disease (LSD) and bovine ephemeral fever (BEF) were constructed, based on the BEFV glycoprotein (G) gene, with or without the BEFV matrix (M) protein gene, inserted into one of two different LSDV backbones, nLSDV∆SOD-UCT or nLSDVSODis-UCT. The inserted gene cassettes were confirmed by PCR; and BEFV protein was shown to be expressed by immunofluorescence. The candidate dual vaccines were initially tested in a rabbit model; neutralization assays using the South African BEFV vaccine (B-Phemeral) strain showed an African consensus G protein gene (Gb) to give superior neutralization compared to the Australian (Ga) gene. The two LSDV backbones expressing both Gb and M BEFV genes were tested in cattle and shown to elicit neutralizing responses to LSDV as well as BEFV after two inoculations 4 weeks apart. The vaccines were safe in cattle and all vaccinated animals were protected against virulent LSDV challenge, unlike a group of control naïve animals, which developed clinical LSD. Both neutralizing and T cell responses to LSDV were stimulated upon challenge. After two inoculations, all vaccinated animals produced BEFV neutralizing antibodies ≥ 1/20, which is considered protective for BEF.

20.
Vaccines (Basel) ; 9(11)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34835214

RESUMO

The modest protective effects of the RV144 HIV-1 vaccine trial have prompted the further exploration of improved poxvirus vector systems that can yield better immune responses and protection. In this study, a recombinant lumpy skin disease virus (LSDV) expressing HIV-1 CAP256.SU gp150 (Env) and a subtype C mosaic Gag was constructed (LSDVGC5) and compared to the equivalent recombinant modified vaccinia Ankara (MVAGC5). In vitro characterization confirmed that cells infected with recombinant LSDV produced Gag virus-like particles containing Env, and that Env expressed on the surface of the cells infected with LSDV was in a native-like conformation. This candidate HIV-1 vaccine (L) was tested in a rabbit model using different heterologous vaccination regimens, in combination with DNA (D) and MVA (M) vectors expressing the equivalent HIV-1 antigens. The four different vaccination regimens (DDMMLL, DDMLML, DDLMLM, and DDLLMM) all elicited high titers of binding and Tier 1A neutralizing antibodies (NAbs), and some regimens induced Tier 1B NAbs. Furthermore, two rabbits in the DDLMLM group developed low levels of autologous Tier 2 NAbs. The humoral immune responses elicited against HIV-1 Env by the recombinant LSDVGC5 were comparable to those induced by MVAGC5.

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