| 1. |
- Beser, Jessica, et al.
(författare)
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Seroprevalence of SARS-CoV-2 in Sweden, April 26 to May 9, 2021
- 2022
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- A national point seroprevalence study of SARS-CoV-2 was conducted in Sweden in April–May 2021. In total, 2860 individuals 3 to 90 years old from a probability-based web panel were included. Results showed that an estimated 32.6% of the population in Sweden had detectable levels of antibodies, and among non-vaccinated 20.1% had detectable levels of antibodies. We tested for differences in seroprevalence between age groups and by sex and estimated seroprevalence among previously infected participants by time since reporting.
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| 2. |
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| 3. |
- Holm, Karin, et al.
(författare)
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Convalescence plasma treatment of COVID-19 : results from a prematurely terminated randomized controlled open-label study in Southern Sweden
- 2021
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Ingår i: BMC Research Notes. - : BioMed Central. - 1756-0500. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Convalescent plasma has been tried as therapy for various viral infections. Early observational studies of convalescent plasma treatment for hospitalized COVID-19 patients were promising, but randomized controlled studies were lacking at the time. The objective of this study was to investigate if convalescent plasma is beneficial to hospitalized patients with COVID-19.Results: Hospitalized patients with confirmed COVID-19 and an oxygen saturation below 94% were randomized 1:1 to receive convalescent plasma in addition to standard of care or standard of care only. The primary outcome was number of days of oxygen treatment to keep saturation above 93% within 28 days from inclusion. The study was prematurely terminated when thirty-one of 100 intended patients had been included. The median time of oxygen treatment among survivors was 11 days (IQR 6–15) for the convalescent plasma group and 7 days (IQR 5–9) for the standard of care group (p = 0.4, median difference -4). Two patients in the convalescent plasma group and three patients in the standard of care group died (p = 0.64, OR 0.49, 95% CI 0.08–2.79). Thus no significant differences were observed between the groups.
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| 4. |
- Kerkman, Priscilla, et al.
(författare)
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Generation of plasma cells and CD27-IgD- B cells during hantavirus infection is associated with distinct pathological findings
- 2021
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Ingår i: Clinical & Translational Immunology (CTI). - : John Wiley & Sons. - 2050-0068. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Human hantavirus infections can cause haemorrhagic fever with renal syndrome (HFRS). The pathogenic mechanisms arenot fully understood, nor if they affect the humoral immune system. The objective of this study was to investigate humoral immune responses to hantavirus infection and to correlate them to the typical features of HFRS: thrombocytopenia and transient kidney dysfunction.Methods: We performed a comprehensive characterisation of longitudinal antiviral B-cell responses of 26 hantavirus patients and combined this with paired clinical data. In addition, we measured extracellular adenosine triphosphate (ATP)and its breakdown products in circulation and performed in vitro stimulations to address its effect on B cells.Results: We found that thrombocytopenia was correlated to an elevated frequency of plasmablasts in circulation. In contrast, kidney dysfunction was indicative of an accumulation of CD27-IgD- B cells and CD27/low plasmablasts. Finally, we provide evidence that high levels of extracellular ATP and matrix metalloproteinase 8 can contribute to shedding of CD27 during human hantavirus infection.Conclusion: Our findings demonstrate that thrombocytopenia and kidneydysfunction associate with distinctly different effects on the humoral immune system. Moreover, hantavirus-infectedindividuals have significantly elevated levels of extracellular ATP incirculation.
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| 5. |
- Kerkman, Priscilla, et al.
(författare)
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The B cell response towards Puumala virus infection : can B cells be infected?
- 2017
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Ingår i: Scandinavian Journal of Immunology. - : John Wiley & Sons. - 0300-9475 .- 1365-3083. ; 86:4, s. 260-260
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Hantavirus infections are rodent-borne viruses causing potential lethal infections in humans. Different hantaviruses exist worldwide, reporting a fatality rate of up to 40%. The Puumala hantavirus (PUUV) is endemic in northern Sweden. This hantavirus strain has a relatively low fatality rate but the hospitalisation rate is high. No vaccine to the virus and no treatment for the disease exist. Despite differences in severity, the immune-mediated pathogenesis of Puumala virus infection is similar to that of highly lethal strains of hantavirus. It is currently unknown how the humoral immune system is affected during hantavirus infection.The aim of this study is to characterise how the humoral immune response is affected during Puumala virus infection. A large number of longitudinal patient samples have been collected. Here, we demonstrate the longitudinal kinetics of the B cell response during Puumala virus infection and show that there is a change in B cell populations during the course of the disease. Furthermore we show that B cells carry known hantavirus receptors. This suggests that Puumala virus may directly infect B cells. Infection of the B cells could affect their function and or phenotype explaining a different immune response. Importantly, in approximately 10–15% of Puumala infected patients we could detect antibodies that could neutralise other hantaviruses in vitro. Samples from these patients could help to generate a monoclonal antibody treatment potentially treating diseases caused by several hantavirus.
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| 6. |
- Lagerqvist, Nina, et al.
(författare)
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Evaluation of 11 SARS-CoV-2 antibody tests by using samples from patients with defined IgG antibody titers
- 2021
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- We evaluated the performance of 11 SARS-CoV-2 antibody tests using a reference set of heat-inactivated samples from 278 unexposed persons and 258 COVID-19 patients, some of whom contributed serial samples. The reference set included samples with a variation in SARS-CoV-2 IgG antibody titers, as determined by an in-house immunofluorescence assay (IFA). The five evaluated rapid diagnostic tests had a specificity of 99.0% and a sensitivity that ranged from 56.3 to 81.6% and decreased with low IFA IgG titers. The specificity was > 99% for five out of six platform-based tests, and when assessed using samples collected ≥ 22 days after symptom onset, two assays had a sensitivity of > 96%. These two assays also detected samples with low IFA titers more frequently than the other assays. In conclusion, the evaluated antibody tests showed a heterogeneity in their performances and only a few tests performed well with samples having low IFA IgG titers, an important aspect for diagnostics and epidemiological investigations.
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| 7. |
- Ljungquist, Oskar, et al.
(författare)
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Convalescent plasma treatment in severely immunosuppressed patients hospitalized with COVID-19 : an observational study of 28 cases
- 2022
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Ingår i: Infectious Diseases. - : Taylor & Francis Group. - 2374-4235 .- 2374-4243 .- 1651-1980. ; 54:4, s. 283-291
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Tidskriftsartikel (refereegranskat)abstract
- Background: Immunosuppressed patients are particularly vulnerable to severe infection from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), risking prolonged viremia and symptom duration. In this study we describe clinical and virological treatment outcomes in a heterogeneous group of patients with severe immunosuppression due to various causes suffering from COVID-19 infection, who were all treated with convalescent plasma (CCP) along with standard treatment.Methods: We performed an observational, retrospective case series between May 2020 to March 2021 at three sites in Skåne, Sweden, with a population of nearly 1.4 million people. All patients hospitalized for COVID-19 who received CCP with the indication severe immunosuppression as defined by the treating physician were included in the study (n = 28).Results: In total, 28 severely immunocompromised patients, half of which previously had been treated with rituximab, who had received in-hospital convalescent plasma treatment of COVID-19 were identified. One week after CCP treatment, 13 of 28 (46%) patients had improved clinically defined as a decrease of at least one point at the WHO-scale. Three patients had increased score points of whom two had died. For 12 patients, the WHO-scale was unchanged.Conclusion: As one of only few studies on CCP treatment of COVID-19 in hospitalized patients with severe immunosuppression, this study adds descriptive data. The study design prohibits conclusions on safety and efficacy, and the results should be interpreted with caution. Prospective, randomized trials are needed to investigate this further.
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| 8. |
- Maleki, Kimia T., et al.
(författare)
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MAIT cell activation is associated with disease severity markers in acute hantavirus infection
- 2021
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Ingår i: Cell Reports Medicine. - : Saunders Elsevier. - 2666-3791. ; 2:3
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Tidskriftsartikel (refereegranskat)abstract
- Hantaviruses are zoonotic RNA viruses that cause severe acute disease in humans. Infected individuals have strong inflammatory responses that likely cause immunopathology. Here, we studied the response of mucosal-associated invariant T (MAIT) cells in peripheral blood of individuals with hemorrhagic fever with renal syndrome (HFRS) caused by Puumala orthohantavirus, a hantavirus endemic in Europe. We show that MAIT cell levels decrease in the blood during HFRS and that residual MAIT cells are highly activated. This activation correlates with HFRS severity markers. In vitro activation of MAIT cells by hantavirus-exposed antigen-presenting cells is dependent on type I interferons (IFNs) and independent of interleukin-18 (IL-18). These findings highlight the role of type I IFNs in virus-driven MAIT cell activation and suggest a potential role of MAIT cells in the disease pathogenesis of viral infections.
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| 9. |
- Mittler, Eva, et al.
(författare)
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Human antibody recognizing a quaternary epitope in the Puumala virus glycoprotein provides broad protection against orthohantaviruses
- 2022
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Ingår i: Science Translational Medicine. - : American Association for the Advancement of Science. - 1946-6234 .- 1946-6242. ; 14:636
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Tidskriftsartikel (refereegranskat)abstract
- The rodent-borne hantavirus Puumala virus (PUUV) and related agents cause hemorrhagic fever with renal syndrome (HFRS) in humans. Other hantaviruses, including Andes virus (ANDV) and Sin Nombre virus, cause a distinct zoonotic disease, hantavirus cardiopulmonary syndrome (HCPS). Although these infections are severe and have substantial case fatality rates, no FDA-approved hantavirus countermeasures are available. Recent work suggests that monoclonal antibodies may have therapeutic utility. We describe here the isolation of human neutralizing antibodies (nAbs) against tetrameric Gn/Gc glycoprotein spikes from PUUV-experienced donors. We define a dominant class of nAbs recognizing the "capping loop" of Gn that masks the hydrophobic fusion loops in Gc. A subset of nAbs in this class, including ADI-42898, bound Gn/Gc complexes but not Gn alone, strongly suggesting that they recognize a quaternary epitope encompassing both Gn and Gc. ADI-42898 blocked the cell entry of seven HCPS- and HFRS-associated hantaviruses, and single doses of this nAb could protect Syrian hamsters and bank voles challenged with the highly virulent HCPS-causing ANDV and HFRS-causing PUUV, respectively. ADI-42898 is a promising candidate for clinical development as a countermeasure for both HCPS and HFRS, and its mode of Gn/Gc recognition informs the development of broadly protective hantavirus vaccines.
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| 10. |
- Rankin, Gregory, et al.
(författare)
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MMP9 Associates with Endothelial Glycocalyx Degradation During Haemorrhagic Fever with Renal Syndrome
- 2019
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Ingår i: Journal of Vascular Research. - : S. Karger. - 1018-1172 .- 1423-0135. ; 56, s. 35-35
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Haemorrhagic fever with renal syndrome (HFRS) is characterized by fever, hypotension, vascular leakage, thrombocytopenia and renal failure. HFRS in Sweden is caused by the Puumala hantavirus and is spread by viral-infested droppings from bank voles. The health care system has little to offer these patients since there is no antiviral treatment and as of yet there is no vaccine prophylaxis available. We previously showed that a marker of endothelial glycocalyx degradation (Syndecan-1) was associated with disease severity and disseminated intravascular coagulation during HFRS (Connolly-Andersen et al., 2014, Open Forum Infect Dis.).Methods: We analysed the levels of other endothelial glycocalyx degradation markers (heparan sulfate, soluble thrombomodulin, albumin), a potential “sheddase”: Matrix Metalloproinase 9 (MMP9) and neutrophil activation/tissue damage (neutrophil gelatinase-associated lipocalin, NGAL) in patient plasma from 44 HFRS patients collected consecutively following disease onset. We used the generalized estimating equation to analyse the association between endothelial glycocalyx degradation, MMP9 levels, neutrophil activation/tissue damage and HFRS disease outcome (need for oxygen, transfusion with blood components, need for intensive care unit (ICU) treatment and renal damage).Results: 44 HFRS patients were included in this study (29 females (66%)); need for oxygen: 11 (25%); transfusion with blood components: 3 (7%) and stay at ICU: 2 (5%)). The levels of MMP9 were significantly associated with all markers of endothelial glycocalyx degradation. Neutrophil activation/tissue damage (NGAL) was also significantly associated with MMP9 and endothelial glycocalyx degradation markers (apart from albumin (p = 0.053). In addition degradation of endothelial glycocalyx associated with HFRS disease outcome.Conclusion: Degradation of the endothelial glycocalyx could be a potential mechanism of HFRS pathogenesis, and potentially MMP9 could contribute to degradation of the endothelial glycocalyx
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