| 1. |
- Bahnan, Wael, et al.
(författare)
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Spike-Dependent Opsonization Indicates Both Dose-Dependent Inhibition of Phagocytosis and That Non-Neutralizing Antibodies Can Confer Protection to SARS-CoV-2
- 2022
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Spike-specific antibodies are central to effective COVID19 immunity. Research efforts have focused on antibodies that neutralize the ACE2-Spike interaction but not on non-neutralizing antibodies. Antibody-dependent phagocytosis is an immune mechanism enhanced by opsonization, where typically, more bound antibodies trigger a stronger phagocyte response. Here, we show that Spike-specific antibodies, dependent on concentration, can either enhance or reduce Spike-bead phagocytosis by monocytes independently of the antibody neutralization potential. Surprisingly, we find that both convalescent patient plasma and patient-derived monoclonal antibodies lead to maximum opsonization already at low levels of bound antibodies and is reduced as antibody binding to Spike protein increases. Moreover, we show that this Spike-dependent modulation of opsonization correlate with the outcome in an experimental SARS-CoV-2 infection model. These results suggest that the levels of anti-Spike antibodies could influence monocyte-mediated immune functions and propose that non-neutralizing antibodies could confer protection to SARS-CoV-2 infection by mediating phagocytosis.
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| 2. |
- Ekström, Johanna, et al.
(författare)
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Diversity of human papillomaviruses in skin lesions
- 2013
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Ingår i: Virology. - : Elsevier BV. - 0042-6822 .- 1096-0341. ; 447:1-2, s. 300-311
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Tidskriftsartikel (refereegranskat)abstract
- Pools of frozen biopsies from patients with squamous cell carcinoma (SCC) (n=29) actinic keratosis (AK) (n=31), keratoacanthoma (n=91) and swab samples from 84 SCCs and 91 AKs were analysed with an extended HPV general primer PCR and high-throughput sequencing of amplimers. We found 273 different HPV isolates (87 known HPV types, 139 previously known HPV sequences (putative types) and 47 sequences from novel putative HPV types). Among the new sequences, five clustered in genus Betapapillomavirus and 42 in genus Gammapapillomavirus. Resequencing of the three pools between 21 to 70 times resulted in the detection of 283 different known or putative HPV types, with 156 different sequences found in only one of the pools. Type-specific PCRs for 37 putative types from an additional 296 patients found only two of these putative types. In conclusion, skin lesions contain a large diversity of HPV types, but most appeared to be rare infections. (C) 2013 Elsevier Inc. All rights reserved.
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| 3. |
- Zaigham, Mehreen, et al.
(författare)
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Intrauterine vertical SARS-CoV-2 infection : a case confirming transplacental transmission followed by divergence of the viral genome
- 2021
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Ingår i: BJOG: An International Journal of Obstetrics & Gynaecology. - : Wiley. - 1471-0528 .- 1470-0328. ; 128:8, s. 1388-1394
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Tidskriftsartikel (refereegranskat)abstract
- A 27-year-old woman (gravida 2, para 1) was transported to the regional university hospital in gestational week (GW) 34 + 4 due to a three-day history of fever, abdominal pain and reduced foetal movements. She had developed a dry cough one day prior to the admission (Figure S1). The woman, was slightly overweight (BMI 27 kg/m2 ) but otherwise healthy. She had normal antenatal check-ups and an obstetric ultrasound at GW 32 + 2 showed a normal foetal weight deviation of +8%1 .
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| 4. |
- Alsved, Malin, et al.
(författare)
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Sources of Airborne Norovirus in Hospital Outbreaks
- 2020
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Ingår i: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1537-6591 .- 1058-4838. ; 70:10, s. 2023-2028
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Noroviruses are the major cause of viral gastroenteritis. Disease transmission is difficult to prevent and outbreaks in healthcare facilities commonly occur. Contact with infected persons and contaminated environments are believed to be the main routes of transmission. However, noroviruses have recently been found in aerosols and airborne transmission has been suggested. The aim of our study was to investigate associations between symptoms of gastroenteritis and presence of airborne norovirus, and to investigate the size of norovirus carrying particles.METHODS: Air sampling was repeatedly performed close to 26 patients with norovirus infections. Samples were analysed for norovirus RNA by RT-qPCR. The times since the patients' last episodes of vomiting and diarrhoea were recorded. Size separating aerosol particle collection was also performed in ward corridors.RESULTS: Norovirus RNA was found in 21 (24%) of 86 air samples from 10 different patients. Only air samples during outbreaks, or before a succeeding outbreak, tested positive for norovirus RNA. Airborne norovirus RNA was also strongly associated with a shorter time period since the last vomiting episode (odds ratio 8.1, p=0.04 within 3 hours since the last vomiting episode). The concentration of airborne norovirus ranged from 5-215 copies/m3, and detectable amounts of norovirus RNA were found in particles <0.95 µm and >4.51 µm.CONCLUSIONS: The results suggest that recent vomiting is the major source of airborne norovirus and imply a connection between airborne norovirus and outbreaks. The presence of norovirus RNA in submicrometre particles indicates that airborne transmission can be an important transmission route.
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| 5. |
- Andersson, Kristin, et al.
(författare)
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Prospective study of genital human papillomaviruses and nonmelanoma skin cancer.
- 2013
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 133:8, s. 1840-1845
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Tidskriftsartikel (refereegranskat)abstract
- Genital high-risk human papillomaviruses (HPVs) cause cervical cancer and are also found in a small proportion of nonmelanoma skin cancers (NMSCs). We used cancer registry linkages to follow the 856,000 serum donors included in the Southern Sweden Microbiology Biobank or the Janus Biobank in Norway, for incident skin cancers occurring up to 30 years after serum donation. Serum samples taken before diagnosis of squamous cell carcinoma (SCC) (N = 633), basal cell carcinoma (BCC) (N = 1990) or other NMSC (N = 153) and matched samples from control donors were tested for antibodies to the genital HPV types 16 and 18. Both HPV 16 and 18 were associated with increased risk for SCC [odds ratio (OR) 1.6, 95% confidence interval (CI) 1.1-2.6 and OR 1.7, 95% CI 1.1-2.5, respectively] and other NMSC (OR 2.3, 95% CI 1.0-5.2 and OR 3.5, 95% CI 1.4-8.7, respectively), but not for BCC. Tumor blocks from HPV16 or 18 seropositive cases were tested with real-time polymerase chain reaction for presence of HPV16 or 18 DNA. No HPV18 DNA was found and only four of 79 SCC cases (two of which were from the perineum/perianal area), one of 221 BCC cases and zero of five cases with other NMSC contained HPV16 DNA. In conclusion, we found prospective evidence that HPV16 and 18 antibodies associate with SCC and other NMSC risk, but not with BCC risk. As only a small proportion of seropositive subjects had evidence of the corresponding HPV DNA in the tumor, most of this excess risk is likely to be due to confounders associated with genital HPV infection.
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| 6. |
- Borgfeldt, Christer, et al.
(författare)
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HPV73 in cervical cancer and distribution of HPV73 variants in cervical dysplasia
- 2021
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 149:4, s. 936-943
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Tidskriftsartikel (refereegranskat)abstract
- HPV73 is classified as possibly oncogenic and is not recognized by most commercial primary HPV screening platforms. The aim was to determine the prevalence of HPV73 among invasive cervical cancers, formalin-fixed paraffin embedded (FFPE) samples (N = 69), from southern Sweden during 2009 to 2010. Another aim was to determine proportions of HPV73 among Aptima HPV assay negative cervical cancers (N = 9, out of 206 cancers) and of high-grade cytological cervical diagnosis (N = 75, out of 5807 high grade lesions) in liquid-based cytology (LBC) samples collected between 2016 and 2019. We also investigated the distribution of HPV73 variants A1, A2 and B among HPV73-positive cases. HPV73 was detected by multiplex MGP-PCR and Luminex, and HPV73 variants were identified by sequencing PCR amplicons. HPV73 was detected in 2.9% (2/69, 95% CI: 0.18-9.9) of the FFPE cervical cancer series. Among the Aptima HPV-negative LBC samples, HPV73 was present in 55.5% (5/9) of the cancers and 29.3% (22/75) of the different grades of cervical diagnosis. The A1, A2 and B variants were present in 6.9% (2/29), 82.7% (24/29) and 10.3% (3/29) of the HPV73-positive women, respectively. Among the seven HPV73 cancer cases (two FFPE samples and five LBC samples), six A2 and one A1 isolate were detected. In summary, the A2 variant of HPV73 was most common in our region. In addition, the observed prevalence of HPV73 (2.9%) in cervical cancers and its relative high occurrence (55.5%) among Aptima HPV-negative cancers urge that detection of HPV73 should be included in future primary HPV screening programs.
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| 7. |
- De Marinis, Yang, et al.
(författare)
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Detection of SARS-CoV-2 by rapid antigen tests on saliva in hospitalized patients with COVID-19
- 2021
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Ingår i: Infection Ecology and Epidemiology. - : Informa UK Limited. - 2000-8686. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The COVID-19 pandemic presents great challenges on transmission prevention, and rapid diagnosis is essential to reduce the disease spread. Various diagnostic methods are available to identify an ongoing infection by nasopharyngeal (NPH) swab sampling. However, the procedure requires handling by health care professionals, and therefore limits the application in household and community settings. Objectives: In this study, we aimed to determine if the detection of SARS-CoV-2 can be performed alternatively on saliva specimens by rapid antigen test. Study Design: Saliva and NPH specimens were collected from 44 patients with confirmed COVID-19. To assess the diagnostic accuracy of point-of-care SARS-CoV-2 rapid antigen test on saliva specimens, we compared the performance of four test products. Results: RT-qPCR was performed and NPH and saliva sampling had similar Ct values, which associated with disease duration. All four antigen tests showed similar trend in detecting SARS-CoV-2 in saliva, but with variation in the ability to detect positive cases. The rapid antigen test with the best performance could detect up to 67% of the positive cases with Ct values lower than 25, and disease duration shorter than 10 days. Conclusion: Our study therefore supports saliva testing as an alternative diagnostic procedure to NPH testing, and that rapid antigen test on saliva provides a potential complement to PCR test to meet increasing screening demand.
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| 8. |
- Izadi, Arman, et al.
(författare)
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Subclass-switched anti-Spike IgG3 oligoclonal cocktails strongly enhance Fc-mediated opsonization
- 2023
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Ingår i: Proceedings of the National Academy of Sciences. - 1091-6490. ; 120:15
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Tidskriftsartikel (refereegranskat)abstract
- Antibodies play a central role in the immune defense against SARS-CoV-2. Emerging evidence has shown that nonneutralizing antibodies are important for immune defense through Fc-mediated effector functions. Antibody subclass is known to affect downstream Fc function. However, whether the antibody subclass plays a role in anti-SARS-CoV-2 immunity remains unclear. Here, we subclass-switched eight human IgG1 anti-spike monoclonal antibodies (mAbs) to the IgG3 subclass by exchanging their constant domains. The IgG3 mAbs exhibited altered avidities to the spike protein and more potent Fc-mediated phagocytosis and complement activation than their IgG1 counterparts. Moreover, combining mAbs into oligoclonal cocktails led to enhanced Fc- and complement receptor-mediated phagocytosis, superior to even the most potent single IgG3 mAb when compared at equivalent concentrations. Finally, in an in vivo model, we show that opsonic mAbs of both subclasses can be protective against a SARS-CoV-2 infection, despite the antibodies being nonneutralizing. Our results suggest that opsonic IgG3 oligoclonal cocktails are a promising idea to explore for therapy against SARS-CoV-2, its emerging variants, and potentially other viruses.
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| 9. |
- Mesher, David, et al.
(författare)
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Population-level effects of human papillomavirus vaccination programs on infections with nonvaccine genotypes
- 2016
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Ingår i: Emerging Infectious Diseases. - : Centers for Disease Control and Prevention (CDC). - 1080-6040 .- 1080-6059. ; 22:10, s. 1732-1740
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Tidskriftsartikel (refereegranskat)abstract
- We analyzed human papillomavirus (HPV) prevalences during prevaccination and postvaccination periods to consider possible changes in nonvaccine HPV genotypes after introduction of vaccines that confer protection against 2 high-risk types, HPV16 and HPV18. Our meta-analysis included 9 studies with data for 13,886 girls and women ≤19 years of age and 23,340 women 20–24 years of age. We found evidence of cross-protection for HPV31 among the younger age group after vaccine introduction but little evidence for reductions of HPV33 and HPV45. For the group this same age group, we also found slight increases in 2 nonvaccine high-risk HPV types (HPV39 and HPV52) and in 2 possible high-risk types (HPV53 and HPV73). However, results between age groups and vaccines used were inconsistent, and the increases had possible alternative explanations; consequently, these data provided no clear evidence for type replacement. Continued monitoring of these HPV genotypes is important.
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| 10. |
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