Sammanfattning Introduktion: Hepatit C är en inflammation av levern orsakad av hepatit C-viruset. Runt 71 miljoner människor världen över är drabbade av den kroniska formen. Effektiva läkemedel finns för att bota sjukdomen, men dessa är dyra och således behövs ett vaccin. Problemet med viruset är den stora variationen av genotyper och subtyper, vilket försvårar vaccinutvecklingen eftersom vaccinet framför allt kommer vara effektivt för en viss grupp smittade. En rad prekliniska studier har gjorts på olika djurslag, där fokus oftast ligger på att generera både antikroppar och att framkalla effektiva T-celler. Tyvärr har dock ingen större framgång gällande vaccinutvecklingen setts till ännu.  Syfte: Litteraturstudiens syfte gick ut på att analysera olika hepatit C-vacciners effekter med avsikten att försöka få en insikt i hur dessa kommer att tillverkas i framtiden för att de ska ge en fullgod effekt hos människor och förhindra smittspridning.   Material och metod: Databasen PubMed användes för att hitta fem olika vetenskapliga artiklar att analysera. Sökorden som användes för att hitta samtliga av dessa studier var ”vaccines hepatitis c”. Endast prekliniska studier valdes ut för analys.  Resultat: Över lag sågs kraftiga responser från immunförsvarets sida till följd av stimulering med olika typer av vacciner. Responserna förmedlades av antikroppar samt cytotoxiska T-celler och T-hjälparceller, ofta genom en produktion av interferon gamma respektive tumörnekrosfaktor alfa. I processen skapades även minnesceller som snabbt kunde reagera vid återexponering av samma antigen.   Slutsats: Fler prekliniska experiment kommer att behöva genomföras innan vaccinen kan ta sig vidare till klinisk fas. Exakt när i framtiden ett vaccin kommer hittas, och om det kommer hittas, är svårt att förutspå. Under tiden finns antivirala läkemedel att tillgå i brist på en mer effektiv lösning. / ABSTRACT Background: Hepatitis C is an inflammation of the liver caused by the hepatitis C virus. Around 71 million people worldwide are affected by the chronic form of the infection. Effective drugs are available to cure the disease, but these are expensive and thus a vaccine is needed. The problem with the virus is the wide variety of genotypes and subtypes, which complicates vaccine development since the vaccine will be especially effective for a particular group of infected individuals. A number of preclinical studies have been conducted on different animal species, where the focus is usually on generating both antibodies and producing efficient T lymphocytes. Unfortunately, no major success regarding vaccine development has yet been seen.  Aim: The purpose of this literature study was to analyze the effects of various hepatitis C vaccines with the intention of trying to gain an insight into how these will be manufactured in the future in order to generate an adequate effect in humans and prevent the spread of infection. Materials and methods: The database PubMed was used to find five different scientific articles to analyze. The keywords used to find each of these studies were "vaccines hepatitis c". Only preclinical studies were selected for evaluation. Results: Overall, strong responses were seen from the immune system as a result of stimulation with different types of vaccines. Responses were mediated by antibodies as well as cytotoxic T cells and T helper cells, often through the production of interferon gamma and tumor necrosis factor alpha. In the process, memory cells were also generated that could react rapidly upon re-exposure of the same antigen. Conclusion: More preclinical experiments will need to be carried out before the vaccines can move forward to clinical trials. Exactly when in the future a vaccine will be found, and if it will be found, is difficult to predict. Meanwhile, antiviral drugs are available in the absence of a more effective solution.

Introduction: Rituximab is a monoclonal antibody used to treat hematological malignancies. The antibody depletes CD20+ B cells via cytotoxic immune mechanisms, such as complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC), which is mainly induced by natural killer (NK) cells. Rituximab is mostly well-tolerated but has been reported to induce the release of large amounts of cytokines in blood, thus causing systemic inflammatory response. Aim: To study rituximab-induced B cell depletion and cytokine release in blood from healthy volunteers and how this was affected by Fc modified versions of the antibody. Methods and materials: Fresh blood from healthy donors (n=3) was incubated with rituximab and Fc modified versions that influence the antibody’s target functions, namely ADCC and CDC, for 4 hours in a blood loop system. Results were measured using multicolor flow cytometry, except for cytokine release in plasma which was measured by enzyme-linked immunosorbent assay (ELISA). Results: Of all treatments, rituximab wild type (WT) showed superior B cell depletion than Fc mutant rituximab. The C1q knock-out variant (rituximab-P331S) and the variant with improved affinity to Fc receptor CD16 (rituximab-GASDALIE) did not differ in depletion. A cytokine release was not detected with the treatments, however, a cytokine stimulation in NK cells was observed. Rituximab-GASDALIE had the most prominent cytokine stimulation and CD107a (marker of NK cell functional activity) expression on NK cells. Rituximab-WT and rituximab-P331S had a minor and similar cytokine stimulation and CD107a expression between each other. Rituximab-IgG2 had minimal B cell depletion, CD107a expression and cytokine stimulation. Conclusions: Rituximab depleted B cells without inducing measurable cytokine release for healthy individuals. Among the treatments, Fc mutant rituximab seem to induce less B cell depletion. Moreover, rituximab-GASDALIE appear to elicit an enhanced NK cell activation. Further studies should include more donors as supplement and the results should be interpreted as complementary data to future data analyzed by performing the loop experiment using blood from patients.

Macrophages are an important key effector cell in the immune system which can practically be found in every tissue. Macrophages have for a long time been considered a population of cells only responsible for pro-inflammatory responses and anti-microbial activities. But over the past decade, many have come to realize the amazing plasticity of macrophages in response to different stimulations. The anti-microbial and pro-inflammatory macrophage is known as classically activated macrophages but newly discovered phenotypes have been revealed named wound-healing macrophages and regulatory macrophages. Through systematic screening we have identified an inducible macrophage activation state which has both wound-healing and regulatory capabilities activated by the novel cytokine combination IL-4/IL-10 with or without TGF-β.

Background Cancer immunotherapy has yielded many successes. Yet to some hard-to-treat brain tumors, such as glioblastoma multiforme (GBM) and diffuse intrinsic pontine glioma (DIPG), it still lacks substantial improvement. Neoantigens resulting from mutations in malignant cells are the key targets for employing adoptive cell therapies. A novel therapeutical strategy may be developed based on the identification of T cell receptors (TCRs) targeting specific neoantigens. Methods Previous work had been done to provide essential materials, including candidate neoantigen peptides, human leukocyte antigen (HLA) genotypes, and peripheral blood mononuclear cell (PBMCs) from patients and healthy donors (HDs). Autologous antigen-presenting cells (APCs) and T cells were isolated from PBMCs for in vitro assays. The activation of T cells against peptides was evaluated by the upregulation of 41BB utilizing flow cytometry (FACS). The cell populations with positive signals were sorted through FACS for TCR sequencing directly or after rapid cell expansion. Results T cells and APCs from 12 HDs were isolated. T cells from 10 HDs were analyzed after in vitro stimulation. T cells from HD30 showed reactions to several public neoantigens; while T cells from HD49 and HD53 showed reactions also to private neoantigens restricted in GBM patient C6. Conclusion The upregulation of 41BB indicated the activation of T cells and the existence of reactive TCRs against either public or private neoantigens in some HDs. Those reactive TCRs and their encoding sequences were the fundamentals of future works. Due to practical reasons, TCR sequencing cannot be done within this project. In future works, wildtype peptides will be included to further validate the results, ensuring identified TCRs recognize neoantigens specifically. Furthermore, the identified TCRs will be cloned and transferred to freshly isolated T cells to confirm their functionality. Keywords Cancer immunotherapy, brain cancer, neoantigen, MHC/HLA, TCR

Crohns sjukdom är en kronisk inflammatorisk sjukdom som påverkar hela gastrointestinala kanalen, från mun ner till ändtarmen. Sjukdomen är progressiv och innefattar olika skov av symptom, som till exempel diarré, magont, rektalblödning, viktminskning, feber och trötthet. Den exakta patofysiologiska orsaken är ej klargjord, men tros bero på olika faktorer som till exempel genetiska faktorer, miljöfaktorer samt immunologiska faktorer. Det är känt att individer med inflammatorisk tarmsjukdom (IBD) uttrycker en större population av mastceller och eosinofiler i tarmsubmukosa, och kan orsaka diverse symptom. Histamin-4 receptorer är G-proteinkopplade receptorer som har en nyckelroll i att förmedla inflammatoriska svar, och spelar en roll i immuncellsmigration till inflammerade vävnader. Syftet med projektet är att studera uttrycket av histaminreceptorn H4 på eosinofiler och mastceller i inflammerad tarmvävnad från patienter med Crohns sjukdom. Det medverkade 16 patienter, varav 8 hade Crohns sjukdom, och 8 var friska kontrollpatienter som opererats för tarmcancer. Uttrycket av eosinofiler, mastceller och Histamin-4 receptorer studerades med hjälp av immunohistokemisk metod. Resultatet visar statistisk signifikanta skillnader mellan patient och kontrollgruppen när det kommer till eosinofiler och mastceller, med ett p-värde <0,05. Det uppvisades ingen signifikant skillnad mellan grupperna när det kom till icke inmärkta celler som uttrycker histamin-4 receptorer, eosinofiler som uttrycker receptorn samt mastceller som uttrycker receptorn. Sammanfattningsvis finns det ett behov att studera detta område igen, med större urval, och möjligtvis förbättrade metoder för att komma fram till säkerställda slutsatser. / Crohn's disease (CD) is a chronic inflammatory disease that affects the entire gastrointestinal tract, from the mouth down to the rectum. The disease is progressive and involves flare-ups of symptoms such as diarrhea, abdominal pain, rectal bleeding, weight loss, fever, and fatigue. The exact pathophysiological cause is unclear but is believed to be related to various factors, including genetic, environmental, and immunological factors. It is known that individuals with inflammatory bowel disease (IBD) express a higher population of mast cells and eosinophils in the intestinal submucosa, which can cause diverse symptoms. Histamine-4 receptors are G-protein-coupled receptors that play a key role in mediating inflammatory responses and are involved in immune cell migration to inflamed tissues. The aim of the project is to study the expression of the histamine receptor H4 on eosinophil granulocytes and mast cells in inflamed intestinal tissue from patients with CD. Sixteen patients participated, including 8 with CD and 8 control patients who underwent surgery for colon cancer. The expression of eosinophils, mast cells, and histamine-4 receptors was studied using immunohistochemical methods. The results show statistically significant differences between the patient and control groups in terms of the number of eosinophils and mast cells, with a p-value <0.05. There was no significant difference between the groups in terms of un-stained cells expressing histamine-4 receptors, eosinophils and/or mast cells expressing the receptor. In conclusion, there is a need to further study this area with larger sample sizes and possibly improved methods to arrive at conclusive findings.

Crimean-Congo Hemorrhagic Fever (CCHF) is a worldwide, severe disease, caused by the CCHF virus (CCHFV). CCHFV is transmitted primarily via Hyalomma tick bite, and/or direct contact with infected blood and tissue. The fatality rate of CCHF is up to 40% and no effective treatments or approved vaccines are available today. One critical component in the development of effective treatments and vaccines is to understand the immune responses due to infection, thus our knowledge regarding immune responses induced by CCHFV need to improve. The aims of this project was to establish an Enzyme-linked immunosorbent assays (ELISAs) based on CCHFV nucleo (N)- or glycoprotein (GC), and further determine antibody titers in longitudinal samples from CCHF survivors using the ELISAs. A unique cohort of 45 CCHF survivors with serum samples collected 4-9, 12- and 24-months post-infection was analyzed. Serum from all 45 CCHF survivor patients at all three time points was confirmed to contain anti-N and anti-GC antibodies. While the titers was high at all time points, there was a significant decrease in anti-N antibody titer over time. The same decrease was not observed for anti-GC antibody titer. Further investigation showed no significant difference in antibody titer due to disease severity, gender or age. In conclusion, ELISAs for detection of antibodies against CCHFV N- and GC-proteins in human serum has been developed. Findings show high titers of both anti-N and anti-GC antibodies up to 2 years post-infection, which indicate a long lasting humoral immune response and potential protection against a new CCHFV infection.

No description available.

No description available.

Demyelinating disorders affect many people around the globe and are characterized by loss of myelin sheaths and oligodendrocyte death, ultimately compromising neuronal signal transmission across the Central Nervous System (CNS). Adult Neural Stem Cells (NSC) are multipotent stem cells with the ability to differentiate into the three types of CNS cells: oligodendrocytes, neurons and astrocytes. Hydrogen peroxide (H2O2) is an inflammatory mediator, often present in demyelinating events, commonly associated with oxidative stress and cell death. However, H2O2 also plays a major role as an intracellular signaling molecule. It has been seen that NSC exposed to H2O2 revealed an increase in proliferation and oligodendrogenesis. In this project, we tried to understand how oligodendrogenesis is modulated at a transcriptional level by H2O2. We have identified the genes Hes1, Foxo1, Nrf2 and Prdx6 as being downregulated in the presence of H2O2 when compared to the non-exposed controls. In order to understand if the differential gene expression is involved in the H2O2-induced oligodendrogenesis, we silenced the genes through siRNA transfection (mimicking the downregulation observed after H2O2 exposure) and analyzed the effects on the transcriptome of NSCs and the impact on cell proliferation and differentiation. Our findings indicate that Foxo1 silencing induced the greatest increase in cell proliferation and that Nrf2 silencing revealed the greatest impact on oligodendrogenesis. While not very significant, Foxo1 silencing seems to induce oligodendrogenesis, and Prdx6 silencing seems to inhibit it. The results obtained give important hints on the role that these genes play in NSCs differentiation and fate determination when exposed to oxidative stress and might allow a better understanding of this complex system.

<p>Cytomegalovirus (CMV) is a widespread infection affecting 50-90% of the human population. A typical silent primary infection is followed by life-long persistence in the host under control by virus-specific CD8 (“killer”) and CD4 (“helper”) T cells. Although harmless in most people, CMV may cause disease and sequelae in patients with deficient cellular immunity, such as AIDS patients, recipients of organ transplants and children who have acquired the virus before birth. In this thesis we have characterized the cellular immunity to CMV in immunocompetent subjects, in patients receiving transplants and in infants.</p><p>In healthy individuals with latent CMV, the frequencies of CMV-specific CD8 T cells varied considerably between the donors. Within the same individual, the changes over time were usually small. In patients with primary, symptomatic CMV infection, the frequencies of CMV-specific CD8 T cells peaked within the first month after the appearance of symptoms. The frequencies then declined to levels similar to those in latently infected CMV carriers. The CD4 T-cell function followed the same pattern, but with lower peak values.</p><p>Immunosuppressed renal transplant patients with latent CMV had CMV-specific CD4 cell function similar to healthy controls. The frequencies of CMV-specific CD8 T cells were also comparable, but their function was impaired. When renal transplant recipients were investigated longitudinally, we found that their CMV-specific T cells decreased rapidly after transplantation. Whereas the frequencies and function of CD8 T cells rebounded within 3 months, CD4 T-cell recovery was impaired during the entire first year after transplantation.</p><p>Finally, the frequencies and function of CMV-specific T-cells were investigated in children with congenital and postnatal CMV. CMV-specific CD8 T cells could be detected in even the youngest children, suggesting that these cells can develop early in life. In contrast, CMV specific CD4 T cells were low or absent in the youngest children but increased slowly with age.</p>