Cystatin C and alpha-1-Microglobulin Predict Severe Acute Kidney Injury in Patients with Hemorrhagic Fever with Renal Syndrome

Puumala orthohantavirus causes hemorrhagic fever with renal syndrome (HFRS) characterized by acute kidney injury (AKI), an abrupt decrease in renal function. Creatinine is routinely used to detect and quantify AKI; however, early AKI may not be reflected in increased creatinine levels. Therefore, kidney injury markers that can predict AKI are needed. The potential of the kidney injury markers urea, cystatin C, α1-microglobulin (A1M) and neutrophil gelatinase-associated lipocalin (NGAL) to detect early AKI during HFRS was studied by quantifying the levels of these markers in consecutively obtained plasma (P) and urine samples (U) for 44 HFRS patients. P-cystatin C and U-A1M levels were significantly increased during early HFRS compared to follow-up. In a receiver operating characteristic (ROC) curve analysis, P-cystatin C, U-A1M and P-urea predicted severe AKI with area under the curve 0.72, 0.73 and 0.71, respectively, whereas the traditional kidney injury biomarkers creatinine and U-albumin did not predict AKI. Nearly half of the HFRS patients (41%) fulfilled the criteria for shrunken pore syndrome, which was associated with the level of inflammation as measured by P-CRP. P-cystatin C and U-A1M are more sensitive and earlier markers compared to creatinine in predicting kidney injury during HFRS

Study of pathogenesis and immune response in human Puumala virus infection

Hantaviruses can cause two severe human diseases: hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). Hantaviruses are spread to humans mainly through inhalation of infectious virions, secreted from infected rodents. The human diseases are characterized by an increased capillary leakage syndrome. Hantaviruses are known to infect endothelial cells, but they are non-cytopathogenic. The mechanism behind human disease is not well understood, but an overactive immune response is implicated in the pathogenesis. The aim of my thesis has been to investigate parts of innate and adaptive immune responses in Puumala virus-infected patients. In paper I we found a sex difference in the cytokine profile during acute infection. Females had significantly higher plasma levels of IL-9, FGF-2, GM-CSF and lower levels of IL-8 and IP-10 compared to males. These differences may affect the activation and function of the immune response. In paper II we studied the phenotype and kinetics of NK cells. We observed that CD56dim NK cells were elevated during acute infection and that these, predominantly NKG2C+ NK cells, remained elevated for at least two months after symptom debut. Our novel finding of a prolonged NK cell response, implicates that NK cells may possess adaptive immunity features.  In paper III we observed a vigorous cytotoxic T cell (CTL) response during acute infection, which contracted in parallel with decrease in viral load. The CTL response was not balanced by an increase in regulatory T cells. The T cells expressed inhibitory immunoregulatory receptors, known to dampen intrinsic T cell activity.  In paper IV, we found that a low IgG response in patients was significantly associated with more severe disease, while the viral load did not affect the outcome. Our findings support the use of passive immunization as a treatment alternative for hantavirus-infected patients. In conclusion, my thesis contributes to an increased knowledge about the immune response in hantavirus-infected patients. The findings, combined with future studies, will hopefully lead to a better understanding of the pathogenesis and possible treatment alternatives

Barns lekvanor : En studie av könssegregerade och könsintegrerade lekar inom förskolan

Syftet med denna studie har varit att undersöka i vilken omfattning pojkar och flickor leker tillsammans i förskolan samt undersöka varför barnen väljer att leka könsintegrerat eller könssegregerat. Studiens karaktär är kvalitativ och datainsamlingsmetoden genomfördes med hjälp av observationer på två förskolor. Resultaten på förskola 1 visade att leken var mer könsintegrerad utomhus än inomhus. Barnen lekte jaga och åkte rutschkana i könsintegrerade grupper utomhus. Inomhus lekte de med mer könsstereotypa leksaker i könssegregerade grupper. Resultaten på förskola 2 visade att leken var mer könsintegrerad än könssegregerad. På denna förskola lekte flickor och pojkar tillsammans utomhus med till exempel dinosaurier eller i sandlådan. Resultaten visade att det som avgjorde om barnen lekte könsintegrerat eller könssegregerat var bland annat deras intresse för leken eller leksaken. Undersökningens slutsats var att det som mer kan påverka om barnens lek blir könssegregerad eller könsintegrerad är inomhus- och utomhusmiljön, men även pedagogens roll i leken

Barns lekvanor : En studie av könssegregerade och könsintegrerade lekar inom förskolan

Syftet med denna studie har varit att undersöka i vilken omfattning pojkar och flickor leker tillsammans i förskolan samt undersöka varför barnen väljer att leka könsintegrerat eller könssegregerat. Studiens karaktär är kvalitativ och datainsamlingsmetoden genomfördes med hjälp av observationer på två förskolor. Resultaten på förskola 1 visade att leken var mer könsintegrerad utomhus än inomhus. Barnen lekte jaga och åkte rutschkana i könsintegrerade grupper utomhus. Inomhus lekte de med mer könsstereotypa leksaker i könssegregerade grupper. Resultaten på förskola 2 visade att leken var mer könsintegrerad än könssegregerad. På denna förskola lekte flickor och pojkar tillsammans utomhus med till exempel dinosaurier eller i sandlådan. Resultaten visade att det som avgjorde om barnen lekte könsintegrerat eller könssegregerat var bland annat deras intresse för leken eller leksaken. Undersökningens slutsats var att det som mer kan påverka om barnens lek blir könssegregerad eller könsintegrerad är inomhus- och utomhusmiljön, men även pedagogens roll i leken

Management projekta razvoja visokotehnološkega produkta

BACKGROUND: Endothelial activation and dysfunction play a central role in the pathogenesis of sepsis and viral hemorrhagic fevers. Hantaviral disease is a viral hemorrhagic fever and is characterized by capillary dysfunction, although the underlying mechanisms for hantaviral disease are not fully elucidated. METHODS: The temporal course of endothelial activation and repair were analyzed during Puumala hantavirus infection and associated with disease outcome and a marker for hypoxia, insulin-like growth factor binding protein 1 (IGFBP-1). The following endothelial activation markers were studied: endothelial glycocalyx degradation (syndecan-1) and leukocyte adhesion molecules (soluble vascular cellular adhesion molecule 1, intercellular adhesion molecule 1, and endothelial selectin). Cytokines associated with vascular repair were also analyzed (vascular endothelial growth factor, erythropoietin, angiopoietin, and stromal cell-derived factor 1). RESULTS: Most of the markers we studied were highest during the earliest phase of hantaviral disease and associated with clinical and laboratory surrogate markers for disease outcome. In particular, the marker for glycocalyx degradation, syndecan-1, was significantly associated with levels of thrombocytes, albumin, IGFBP-1, decreased blood pressure, and disease severity. CONCLUSIONS: Hantaviral disease outcome was associated with endothelial dysfunction. Consequently, the endothelium warrants further investigation when designing future medical interventions

Clinical and genomic characterisation of a fatal Puumala orthohantavirus case with low levels of neutralising antibodies

BACKGROUND: Orthohantaviruses are rodent-borne emerging viruses that cause haemorrhagic fever with renal syndrome (HFRS) in Eurasia and hantavirus pulmonary syndrome in America. Transmission between humans have been reported and the case-fatality rate ranges from 0.4% to 40% depending on virus strain. There is no specific and efficient treatment for patients with severe HFRS. Here, we characterised a fatal case of HFRS and sequenced the causing Puumala orthohantavirus (PUUV). METHODS: PUUV RNA and virus specific neutralising antibodies were quantified in plasma samples from the fatal case and other patients with non-fatal PUUV infection. To investigate if the causing PUUV strain was different from previously known strains, Sanger sequencing was performed directly from the patient's plasma. Biopsies obtained from autopsy were stained for immunohistochemistry. RESULTS: The patient had approximately tenfold lower levels of PUUV neutralising antibodies and twice higher viral load than was normally seen for patients with less severe PUUV infection. We could demonstrate unique mutations in the S and M segments of the virus that could have had an impact on the severity of infection. Due to the severe course of infection, the patient was treated with the bradykinin receptor inhibitor icatibant to reduce bradykinin-mediated vessel permeability and maintain vascular circulation. CONCLUSIONS: Our data suggest that bradykinin receptor inhibitor may not be highly efficient to treat patients that are at an advanced stage of HFRS. Low neutralising antibodies and high viral load at admission to the hospital were associated with the fatal outcome and may be useful for future predictions of disease outcome

Circulating extracellular vesicle tissue factor activity during orthohantavirus infection is associated with intravascular coagulation

BACKGROUND: Puumala (PUUV) orthohantavirus causes hemorrhagic fever with renal syndrome (HFRS). HFRS patients have an activated coagulation system with increased risk of disseminated intravascular coagulation (DIC) and venous thromboembolism (VTE). The aim of the study was to determine if circulating extracellular vesicle tissue factor (EVTF) activity levels associates with DIC and VTE (grouped as intravascular coagulation) in HFRS patients. METHODS: Longitudinal samples were collected from 88 HFRS patients. Patients were stratified into groups of those with intravascular coagulation (n=27) and those who did not (n=61). We measured levels of circulating EVTF activity, fibrinogen, activated partial prothrombin time, prothrombin time international normalized ratio, D-dimer, tissue plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1) and platelets. RESULTS: Plasma EVTF activity was transiently increased during HFRS. Levels of EVTF activity significantly associated with plasma tPA and PAI-1, suggesting endothelial cells as a potential source. Patients with intravascular coagulation had significantly higher peak EVTF activity levels compared to those who did not. The peak EVTF activity value predicting intravascular coagulation was 0.51 ng/L with 63% sensitivity and 61% specificity with AUC 0.63 (95% CI 0.51 - 0.76), p-value 0.046. CONCLUSIONS: Increased circulating EVTF activity during HFRS is associated with intravascular coagulation

Generation of plasma cells and CD27 - IgD - B cells during hantavirus infection is associated with distinct pathological findings

International audienceObjective : Human hantavirus infections can cause haemorrhagic fever with renal syndrome (HFRS). The pathogenic mechanisms are not 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 kidney dysfunction associate with distinctly different effects on the humoral immune system. Moreover, hantavirus-infected individuals have significantly elevated levels of extracellular ATP in circulation

At-home sampling to meet geographical challenges for serological assessment of SARS-CoV-2 exposure in a rural region of northern Sweden, March to May 2021 : a retrospective cohort study

Background: The current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture for testing is usually performed by trained staff at healthcare centres. Long travel distances to healthcare centres in rural regions may introduce a bias of testing towards relatively large communities with closer access. Rural regions are therefore often not represented in population-based data. Aim: The aim of this retrospective cohort study was to develop and implement a strategy for at-home testing in a rural region of Sweden during spring 2021, and to evaluate its role to provide equal health care for its inhabitants. Methods: We developed a sensitive method to measure antibodies to the S-protein of SARS-CoV-2 and optimised this assay for clinical use together with a strategy of at-home capillary blood sampling. Results: We demonstrated that our ELISA gave comparable results after analysis of capillary blood or serum from SARS-CoV-2-experienced individuals. We demonstrated stability of the assay under conditions that reflected temperature and humidity during winter or summer. By assessment of capillary blood samples from 4,122 individuals, we could show both feasibility of the strategy and that implementation shifted the geographical spread of testing in favour of rural areas. Conclusion: Implementation of at-home sampling enabled citizens living in remote rural areas access to centralised and sensitive laboratory antibody tests. The strategy for testing used here could therefore enable disease control authorities to get rapid access to information concerning immunity to infectious diseases, even across vast geographical distance