Chromosome-Scale Genome Assembly of the Sheep-Biting Louse Bovicola ovis Using Nanopore Sequencing Data and Pore-C Analysis.

Bovicola ovis, commonly known as the sheep-biting louse, is an ectoparasite that adversely affects the sheep industry. Sheep louse infestation lowers the quality of products, including wool and leather, causing a loss of approximately AUD 123M per annum in Australia alone. The lack of a high-quality genome assembly for the sheep-biting louse, as well as any closely related livestock lice, has hindered the development of louse research and management control tools. In this study, we present the assembly of B. ovis with a genome size of ~123 Mbp based on a nanopore long-read sequencing library and Illumina RNA sequencing, complemented with a chromosome-level scaffolding using the Pore-C multiway chromatin contact dataset. Combining multiple alignment and gene prediction tools, a comprehensive annotation on the assembled B. ovis genome was conducted and recalled 11,810 genes as well as other genomic features including orf, ssr, rRNA and tRNA. A manual curation using alignment with the available closely related louse species, Pediculus humanus, increased the number of annotated genes to 16,024. Overall, this study reported critical genetic resources and biological insights for the advancement of sheep louse research and the development of sustainable control strategies in the sheep industry.

Extended Genotyping to Stratify the Risk of CIN2+ in Women with Persistent HPV Infection, Negative Cytology and Type 3 Transformation Zone.

Persistent human papillomavirus (HPV) infection is recognized as a major risk factor for cervical cancer. Women with persistent HPV and negative cytology are at greater risk of CIN2+ than women with negative infection. The diagnosis becomes more complicated when the woman has a type 3 transformation zone at colposcopy. The aim of this study was to determine the prevalence of CIN2+ in women with persistent HPV, negative cytology and TZ3; how to stratify the risk of CIN2+; and what the best diagnostic strategy is, given TZ3. METHODS: In a multicenter retrospective cohort study, we enrolled women with negative cytology and TZ3 among the 213 women referred for colposcopy for persistent HPV. The average age of the women was 53 years; in particular, 83% were postmenopausal women. In the presence of a TZ3, the entire transformation zone cannot be explored, making colposcopy and targeted biopsy useless and inadequate, with great risks of underdiagnosis or missed diagnosis. Women with TZ3 underwent diagnostic LEEP to ensure correct diagnoses. RESULTS: The study highlighted 19% (16/84) of CIN2+ lesions, a higher frequency of non-HPV 16/18 genotypes (76.2%), and 50% of CIN2+ lesions being due to non-HPV 16/18 genotypes. Furthermore, more than half of the women (80.9%) had normal histopathological results in the LEEP sample. CONCLUSION: Women with viral persistence, negative cytology, and TZ3 have a 19% risk of CIN2+; genotyping helps stratify risk, but extensive genotyping is necessary instead of partial genotyping (16/18), referring to a population of women over 50 years old in which the prevalence of genotypes 16,18 decreases and the prevalence of other genotypes increases; diagnostic LEEP is excessive (only 16 cases of CIN2+ out of 48 cases treated), even though 83% of women had viral clearance after LEEP; p16/Ki67 double staining could be a potential risk marker, which would only highlight women at risk of CIN2+ to undergo LEEP. To individualize the diagnostic workup and treatment and minimize the risk of under diagnosis and overtreatment, future studies should explore the use of extended genotyping and new biomarkers for individual risk stratification.

The Coexistence of Cervical Intraepithelial Neoplasia (CIN3) and Adenocarcinoma In Situ (AIS) in LEEP Excisions Performed for CIN3.

The purpose of this study was to evaluate the incidence of AIS and AC in the histological cone of women treated for CIN3. Furthermore, through the study of the specific HR HPV genotypes, we obtained more information on the possible different nature between the single CIN3 lesion and the CIN3 coexisting with the glandular lesion. METHODS: A sample of 414 women underwent LEEP for CIN3. The study sample consisted of 370 women with a CIN3 lesion alone and 44 women with a CIN3 lesion coexisting with AIS or adenocarcinoma. We studied the individual HR HPV genotypes and their frequency in the two groups under study. Furthermore, the therapeutic results and follow-ups for the population were studied on the entire study sample. RESULTS: In patients with a single CIN3 lesion, 11 high-risk genotypes were detected; in patients with CIN3 associated with AIS or AC, only 4 different genotypes were detected (16, 18, 45, 33). Overall, the frequency of HPV 18 was significantly higher in CIN3 coexisting with AIS compared to solitary CIN3 lesions, χ2 = 27.73 (p < 0.001), while the frequency of other high-risk genotypes was significantly higher in patients with a single CIN3 than in patients with CIN3 coexisting with AIS. In our study population, mixed lesions (CIN3 coexisting with AIS), unlike their squamous counterparts (single CIN3 lesions), were characterized by skip lesions, which demonstrate more aggressive behavior and a higher rate of viral persistence and recurrence. CONCLUSION: A relatively high rate (10.7%) of AIS-AC was found in women treated for CIN3. Our study confirms the multifocal biological nature of the CIN3 lesion coexisting with AIS compared to the single CIN3 lesion. All this justifies the different treatments to which CIN3 lesions coexisting with AIS are addressed; in fact, the latter are treated with hysterectomy, while CIN3 is treated with conization alone.

Overexpression of E6/E7 mRNA HPV Is a Prognostic Biomarker for Residual Disease Progression in Women Undergoing LEEP for Cervical Intraepithelial Neoplasia 3.

The risk of overtreatment or not treating an occult carcinoma exists in women at risk of residual disease after a LEEP excision for CIN3. Our goal was to discover an efficient method to select patients requiring a second LEEP from those requiring a FU only through an mRNA-detection test. In a population of 686 women undergoing a LEEP excision for CIN 3, we selected 285 women at risk of residual disease and subjected them to a search for E6/E7 mRNA HPV. The women with negative mRNA were subjected to a follow up, while the women with positive mRNA were subjected to a second LEEP. The histological examination of the second cone revealed 120 (85.7%) cases of residual disease in the mRNA-positive women: 40 cases of CIN2, 51 cases of CIN3, 11 cases of squamous microinvasive carcinoma, 7 cases of squamous carcinoma, 9 cases of AIS (adenocarcinoma in situ) and 2 cases of adenocarcinoma. Among the mRNA-negative women undergoing a follow up, there were only five cases of residual disease. During the follow-up period of about 6 years, we witnessed the regression of the residual disease and the elimination of the virus, just as predicted by the negative result of the mRNA test. Testing patients for E6/E7 mRNA allowed us to identify women with residual disease (CIN2+) and treat them appropriately.

Synergistic Effect of Two Nanotechnologies Enhances the Protective Capacity of the Theileria parva Sporozoite p67C Antigen in Cattle.

East Coast fever (ECF), caused by Theileria parva, is the most important tick-borne disease of cattle in sub-Saharan Africa. Practical disadvantages associated with the currently used live-parasite vaccine could be overcome by subunit vaccines. An 80-aa polypeptide derived from the C-terminal portion of p67, a sporozoite surface Ag and target of neutralizing Abs, was the focus of the efforts on subunit vaccines against ECF and subjected to several vaccine trials with very promising results. However, the vaccination regimen was far from optimized, involving three inoculations of 450 µg of soluble p67C (s-p67C) Ag formulated in the Seppic adjuvant Montanide ISA 206 VG. Hence, an improved formulation of this polypeptide Ag is needed. In this study, we report on two nanotechnologies that enhance the bovine immune responses to p67C. Individually, HBcAg-p67C (chimeric hepatitis B core Ag virus-like particles displaying p67C) and silica vesicle (SV)-p67C (s-p67C adsorbed to SV-140-C18, octadecyl-modified SVs) adjuvanted with ISA 206 VG primed strong Ab and T cell responses to p67C in cattle, respectively. Coimmunization of cattle (Bos taurus) with HBcAg-p67C and SV-p67C resulted in stimulation of both high Ab titers and CD4 T cell response to p67C, leading to the highest subunit vaccine efficacy we have achieved to date with the p67C immunogen. These results offer the much-needed research depth on the innovative platforms for developing effective novel protein-based bovine vaccines to further the advancement.

A partially purified outer membrane protein VirB9-1 for low-cost nanovaccines against Anaplasma marginale.

Anaplasma marginale is a devastating tick-borne pathogen causing anaplasmosis in cattle and results in significant economic loss to the cattle industry worldwide. Currently, there is no widely accepted vaccine against A. marginale. New generation subunit vaccines against A. marginale, which are much safer, more efficient and cost-effective, are in great need. The A. marginale outer membrane protein VirB9-1 is a promising antigen for vaccination. We previously have shown that soluble recombinant VirB9-1 protein can be expressed and purified from Escherichia coli and induce a high level of humoral and cellular immunity in mice. In this study, we re-formulated the nanovaccines using the partially-purified VirB9-1 protein as the antigen and hollow nano-size silica vesicles (SV-100) as the adjuvant. We simplified the purification method to obtain the partially-purified antigen VirB9-1 with a six-fold higher yield. The new formulations using the partially-purified VirB9-1 protein achieved higher antibody and cell-mediated immune responses compared to the purified ones. This finding suggests that the partially-purified VirB9-1 protein performs better than the purified ones in the vaccination against A. marginale, and a certain level of contaminants in the protein antigen can be self-adjuvant and boost immunogenicity together with the nanoparticle adjuvant. This may lead to finding a "Goldilocks" level of contaminants. The new nanovaccine formulation using partially-purified antigens along with nanoparticle adjuvants offers an alternative strategy for making cheaper veterinary vaccines.

Immunogenicity of Outer Membrane Proteins VirB9-1 and VirB9-2, a Novel Nanovaccine against Anaplasma marginale.

Anaplasma marginale is the most prevalent tick-borne livestock pathogen and poses a significant threat to cattle industry. In contrast to currently available live blood-derived vaccines against A. marginale, alternative safer and better-defined subunit vaccines will be of great significance. Two proteins (VirB9-1 and VirB9-2) from the Type IV secretion system of A. marginale have been shown to induce humoral and cellular immunity. In this study, Escherichia coli were used to express VirB9-1 and VirB9-2 proteins. Silica vesicles having a thin wall of 6 nm and pore size of 5.8 nm were used as the carrier and adjuvant to deliver these two antigens both as individual or mixed nano-formulations. High loading capacity was achieved for both proteins, and the mouse immunisation trial with individual as well as mixed nano-formulations showed high levels of antibody titres over 107 and strong T-cell responses. The mixed nano-formulation also stimulated high-level recall responses in bovine T-cell proliferation assays. These results open a promising path towards the development of efficient A. marginale vaccines and provide better understanding on the role of silica vesicles to deliver multivalent vaccines as mixed nano-formulations able to activate both B-cell and T-cell immunity, for improved animal health.

Silica Vesicle Nanovaccine Formulations Stimulate Long-Term Immune Responses to the Bovine Viral Diarrhoea Virus E2 Protein.

Bovine Viral Diarrhoea Virus (BVDV) is one of the most serious pathogen, which causes tremendous economic loss to the cattle industry worldwide, meriting the development of improved subunit vaccines. Structural glycoprotein E2 is reported to be a major immunogenic determinant of BVDV virion. We have developed a novel hollow silica vesicles (SV) based platform to administer BVDV-1 Escherichia coli-expressed optimised E2 (oE2) antigen as a nanovaccine formulation. The SV-140 vesicles (diameter 50 nm, wall thickness 6 nm, perforated by pores of entrance size 16 nm and total pore volume of 0.934 cm3 g(-1)) have proven to be ideal candidates to load oE2 antigen and generate immune response. The current study for the first time demonstrates the ability of freeze-dried (FD) as well as non-FD oE2/SV140 nanovaccine formulation to induce long-term balanced antibody and cell mediated memory responses for at least 6 months with a shortened dosing regimen of two doses in small animal model. The in vivo ability of oE2 (100 µg)/SV-140 (500 µg) and FD oE2 (100 µg)/SV-140 (500 µg) to induce long-term immunity was compared to immunisation with oE2 (100 µg) together with the conventional adjuvant Quil-A from the Quillaja saponira (10 µg) in mice. The oE2/SV-140 as well as the FD oE2/SV-140 nanovaccine generated oE2-specific antibody and cell mediated responses for up to six months post the final second immunisation. Significantly, the cell-mediated responses were consistently high in mice immunised with oE2/SV-140 (1,500 SFU/million cells) at the six-month time point. Histopathology studies showed no morphological changes at the site of injection or in the different organs harvested from the mice immunised with 500 µg SV-140 nanovaccine compared to the unimmunised control. The platform has the potential for developing single dose vaccines without the requirement of cold chain storage for veterinary and human applications.

Immunisation of Sheep with Bovine Viral Diarrhoea Virus, E2 Protein Using a Freeze-Dried Hollow Silica Mesoporous Nanoparticle Formulation.

Bovine viral diarrhoea virus 1 (BVDV-1) is arguably the most important viral disease of cattle. It is associated with reproductive, respiratory and chronic diseases in cattle across the world. In this study we have investigated the capacity of the major immunological determinant of BVDV-1, the E2 protein combined with hollow type mesoporous silica nanoparticles with surface amino functionalisation (HMSA), to stimulate immune responses in sheep. The current work also investigated the immunogenicity of the E2 nanoformulation before and after freeze-drying processes. The optimal excipient formulation for freeze-drying of the E2 nanoformulation was determined to be 5% trehalose and 1% glycine. This excipient formulation preserved both the E2 protein integrity and HMSA particle structure. Sheep were immunised three times at three week intervals by subcutaneous injection with 500 µg E2 adsorbed to 6.2 mg HMSA as either a non-freeze-dried or freeze-dried nanoformulation. The capacity of both nanovaccine formulations to generate humoral (antibody) and cell-mediated responses in sheep were compared to the responses in sheep immunisation with Opti-E2 (500 µg) together with the conventional adjuvant Quil-A (1 mg), a saponin from the Molina tree (Quillaja saponira). The level of the antibody responses detected to both the non-freeze-dried and freeze-dried Opti-E2/HMSA nanoformulations were similar to those obtained for Opti-E2 plus Quil-A, demonstrating the E2 nanoformulations were immunogenic in a large animal, and freeze-drying did not affect the immunogenicity of the E2 antigen. Importantly, it was demonstrated that the long term cell-mediated immune responses were detectable up to four months after immunisation. The cell-mediated immune responses were consistently high in all sheep immunised with the freeze-dried Opti-E2/HMSA nanovaccine formulation (>2,290 SFU/million cells) compared to the non-freeze-dried nanovaccine formulation (213-500 SFU/million cells). This study is the first to demonstrate that a freeze-dried silica mesoporous nanovaccine formulation gives balanced immune responses in a production animal.

Silica vesicles as nanocarriers and adjuvants for generating both antibody and T-cell mediated immune resposes to Bovine Viral Diarrhoea Virus E2 protein.

Bovine Viral Diarrhoea Virus (BVDV) is widely distributed in cattle industries and causes significant economic losses worldwide annually. A limiting factor in the development of subunit vaccines for BVDV is the need to elicit both antibody and T-cell-mediated immunity as well as addressing the toxicity of adjuvants. In this study, we have prepared novel silica vesicles (SV) as the new generation antigen carriers and adjuvants. With small particle size of 50 nm, thin wall (~6 nm), large cavity (~40 nm) and large entrance size (5.9 nm for SV-100 and 16 nm for SV-140), the SV showed high loading capacity (∼ 250 µg/mg) and controlled release of codon-optimised E2 (oE2) protein, a major immunogenic determinant of BVDV. The in vivo functionality of the system was validated in mice immunisation trials comparing oE2 plus Quil A (50 µg of oE2 plus 10 µg of Quil A, a conventional adjuvant) to the oE2/SV-140 (50 µg of oE2 adsorbed to 250 µg of SV-140) or oE2/SV-140 together with 10 µg of Quil A. Compared to the oE2 plus Quil A, which generated BVDV specific antibody responses at a titre of 10(4), the oE2/SV-140 group induced a 10 times higher antibody response. In addition, the cell-mediated response, which is essential to recognise and eliminate the invading pathogens, was also found to be higher [1954-2628 spot forming units (SFU)/million cells] in mice immunised with oE2/SV-140 in comparison to oE2 plus Quil A (512-1369 SFU/million cells). Our study has demonstrated that SV can be used as the next-generation nanocarriers and adjuvants for enhanced veterinary vaccine delivery.

Freeze-drying of ovalbumin loaded mesoporous silica nanoparticle vaccine formulation increases antigen stability under ambient conditions.

Amino functionalised mesoporous silica nanoparticles (AM-41) have been identified as a promising vaccine delivery material. The capacity of AM-41 to stabilise vaccine components at ambient temperature (23-27°C) was determined by adsorbing the model antigen ovalbumin (OVA) to AM-41 particles (OVA-41). The OVA-41 was successfully freeze-dried using the excipients 5% trehalose and 1% PEG8000. The immunological activity of OVA and the nanoparticle structure were maintained following two months storage at ambient temperature. The results of immunisation studies in mice with reconstituted OVA-41 demonstrated the induction of humoral and cell-meditated immune responses. The capacity of AM-41 particles to facilitate ambient storage of vaccine components without the loss of immunological potency will underpin the further development of this promising vaccine delivery platform.

MMP7 expression in colorectal tumours of different stages.

BACKGROUND/AIM: Matrix metalloproteinases (MMPs) are involved in cancer biology. Expression of MMP7 (matrilysin) in colorectal cancer is associated with metastatic disease even though it is expressed in most tumour states. In the present study, our purpose was to analyze MMP7 in bowel and lymph nodes of different tumour stages and to evaluate its expression as a cancer biomarker. PATIENTS AND METHODS: 28 patients surgically-treated for benign and malignant colorectal tumours were recruited and analyzed for MMP7 in tumoural tissue, lymph nodes and serum by histology, immunohistochemistry, ELISA and western blotting. RESULTS: Immunohistochemistry showed prevalent expression of MMP7 in advanced cancer. A significant increase (p<0.001) was evident in serum of stage III/IV cancers compared to both adenomas and non-metastatic disease. MMP7 was increased in cancer tissues with prevalence in stage I/II. Lymph nodes presented a significant increase of MMP7 (p<0.05 adenoma vs. stage I/II and p<0.001 vs. stage III/IV). CONCLUSION: MMP7 increases with dysplasia and cancer disease stage in tumour tissue as well as in the regional lymph nodes. It may be used as a complement in investigating suspected locally advanced cancer.

Femoro-femoral crossover graft and simultaneous reconstruction of the proximal deep femoral artery.

BACKGROUND: The goal of this study was to describe and review the results of a technique in which reconstruction of the common and profunda femoral arteries is combined with a femoro-femoral crossover graft using the same synthetic graft. A synthetic bifurcated graft (such as the ones used for aortobifemoral reconstruction), in which one limb is cut off, is used, leaving an enlarging patch at the end where the proximal anastomosis will be fashioned. METHODS: From January 1972 to January 2000, 6 patients underwent this reconstruction for severe limb ischemia. Patients were followed up in the outpatient clinic every 6 months. RESULTS: No postoperative mortality and no major complications were seen. One patient had a superficial wound infection, which resolved with conservative treatment. Five patients had a patent graft at an average follow-up of 39 months. CONCLUSIONS: Using the same synthetic graft allows angioplasty of the common and profunda femoral arteries of the donor side and revascularization of the opposite lower limb, with good short- and long-term results.

Mesoporous silica nanoparticles as antigen carriers and adjuvants for vaccine delivery.

Vaccines have been at the forefront of improving human health for over two centuries. The challenges faced in developing effective vaccines flow from complexities associated with the immune system and requirement of an efficient and safe adjuvant to induce a strong adaptive immune response. Development of an efficient vaccine formulation requires careful selection of a potent antigen, efficient adjuvant and route of delivery. Adjuvants are immunological agents that activate the antigen presenting cells (APCs) and elicit a strong immune response. In the past decade, the use of mesoporous silica nanoparticles (MSNs) has gained significant attention as potential delivery vehicles for various biomolecules. In this review, we aim to highlight the potential of MSNs as vaccine delivery vehicles and their ability to act as adjuvants. We have provided an overview on the latest progress on synthesis, adsorption and release kinetics and biocompatibility of MSNs as next generation antigen carriers and adjuvants. A comprehensive summary on the ability of MSNs to deliver antigens and elicit both humoral and cellular immune responses is provided. Finally, we give insight on fundamental challenges and some future prospects of these nanoparticles as adjuvants.

Mesoporous silica nanoparticles act as a self-adjuvant for ovalbumin model antigen in mice.

Immunization to the model protein antigen ovalbumin (OVA) is investigated using MCM-41 mesoporous silica nanoparticles as a novel vaccine delivery vehicle and adjuvant system in mice. The effects of amino surface functionalization and adsorption time on OVA adsorption to nanoparticles are assessed. Amino-functionalized MCM-41 (AM-41) shows an effect on the amount of OVA binding, with 2.5-fold increase in binding capacity (72 mg OVA/g AM-41) compared to nonfunctionalized MCM-41 (29 mg OVA/g MCM-41). Immunization studies in mice with a 10 µg dose of OVA adsorbed to AM-41 elicits both antibody and cell-mediated immune responses following three subcutaneous injections. Immunizations at a lower 2 µg dose of OVA adsorbed to AM-41 particles results in an antibody response but not cell-mediated immunity. The level of antibody responses following immunization with nanoformulations containing either 2 µg or 10 µg of OVA are only slightly lower than that in mice which receive 50 µg OVA adjuvanted with QuilA, a crude mixture of saponins extracted from the bark of the Quillaja saponaria Molina tree. This is a significant result, since it demonstrates that AM-41 nanoparticles are self-adjuvanting and elicit immune responses at reduced antigen doses in vivo compared to a conventional delivery system. Importantly, there are no local or systemic negative effects in animals injected with AM-41. Histopathological studies of a range of tissue organs show no changes in histopathology of the animals receiving nanoparticles over a six week period. These results establish the biocompatible MCM-41 silica nanoparticles as a new method for vaccine delivery which incorporates a self-adjuvant effect.

Worsening of preoperative foot ischemia after occlusion of polytetrafluoroethylene femorotibial grafts: a comparison with saphenous vein grafts.

BACKGROUND: The aim of this study was to determine the hemodynamic and clinical changes after occlusion of polytetrafluoroethylene (PTFE) femorotibial grafts. METHODS: Twenty-seven patients were randomly selected from all patients who underwent femorotibial bypass grafting in our department. In 10 patients, the reversed autologous saphenous vein was used as graft, and in 17 patients a PTFE prosthesis was used. Out of the latter 17 patients, 10 began long-term aspirin therapy and 7 began oral anticoagulation with warfarin. RESULTS: Nine out of the 10 patients with occluded PTFE grafts and who received only aspirin therapy had a critical ischemia after occlusion of the graft, and 4 underwent major amputation. Among the 10 patients with occluded autologous vein bypass, critical ischemia was present in only 4 patients, and only 2 required some form of surgical therapy with no case of major amputation. CONCLUSIONS: After occlusion of a PTFE femorotibial graft, there is a condition of critical ischemia that is less common after occlusion of a vein graft. Oral anticoagulation seems to prevent these negative changes.