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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. [ABSTRACT FROM AUTHOR]

Despite treatment and other interventions, an effective prophylactic HIV vaccine is still an essential goal in the control of HIV. Inducing robust and long-lasting antibody responses is one of the main targets of an HIV vaccine. The delivery of HIV envelope glycoproteins (Env) using nanoparticle (NP) platforms has been shown to elicit better immunogenicity than soluble HIV Env. In this paper, we describe the development of a nanoparticle-based vaccine decorated with HIV Env using the SpyCatcher/SpyTag system. The Env utilised in this study, CAP255, was derived from a transmitted founder virus isolated from a patient who developed broadly neutralising antibodies. Negative stain and cryo-electron microscopy analyses confirmed the assembly and stability of the mi3 into uniform icosahedral NPs surrounded by regularly spaced CAP255 gp140 Env trimers. A three-dimensional reconstruction of CAP255 gp140 SpyTag–SpyCatcher mi3 clearly showed Env trimers projecting from the centre of each of the pentagonal dodecahedral faces of the NP. To our knowledge, this is the first study to report the formation of SpyCatcher pentamers on the dodecahedral faces of mi3 NPs. To investigate the immunogenicity, rabbits were primed with two doses of DNA vaccines expressing the CAP255 gp150 and a mosaic subtype C Gag and boosted with three doses of the NP-developed autologous Tier 2 CAP255 neutralising antibodies (Nabs) and low levels of heterologous CAP256SU NAbs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 LSDVSODis-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, pMExTp67HA (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. [ABSTRACT FROM AUTHOR]

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 plantderived 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 in Escherichia coli and 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. [ABSTRACT FROM AUTHOR]

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 β1,2‐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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 AllplexTM 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 urealyticumpathobiont 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 AGYWin 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Given the complex maturation requirements of viral glycoproteins and the challenge they often pose for expression in plants, the identification of host constraints precluding their efficient production is a priority for the molecular farming of vaccines. Building on previous work to improve viral glycoprotein production in plants, we investigated the production of a soluble SARS-CoV-2 spike comprising the ectopic portion of the glycoprotein. This was successfully transiently expressed in N. benthamiana by co-expressing the human lectin-binding chaperone calreticulin, which substantially increased the accumulation of the glycoprotein. The spike was mostly unprocessed unless the protease furin was co-expressed which resulted in highly efficient processing of the glycoprotein. Co-expression of several broad-spectrum protease inhibitors did not improve accumulation of the protein any further. The protein was successfully purified by affinity chromatography and gel filtration, although the purified product was heterogenous and the yields were low. Immunogenicity of the antigen was tested in BALB/c mice, and cellular and antibody responses were elicited after low dose inoculation with the adjuvanted protein. This work constitutes an important proof-of-concept for host plant engineering in the context of rapid vaccine development for SARS-CoV-2 and other emerging viruses. [ABSTRACT FROM AUTHOR]