京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22364号 / 医博第4605号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 濵﨑 洋子, 教授 松田 文彦, 教授 遊佐 宏介 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Introduktion: Psoriasis är en kronisk inflammatorisk systemsjukdom som drabbar främst hud och leder.  På grund av mycket snabbt tillväxt av hudceller ger psoriasis utslag på huden.  En av de vanligaste typerna av psoriasis är plack-psoriasis som kännetecknas av större än 0,5 cm i diameter runda fjällande hudutslag som kliar. Mekanismen som ligger bakom plack-psoriasis medieras med hjälp av T-celler och dendritiska celler som är en viktig del av immunsystemet. Stimulering av dessa immunceller leder till frisättning av följande proinflammatoriska cytokiner såsom IL-17, IFN-γ, TNF samt IL-22. Dessa cytokiner utövar sin effekt på keratinocyter genom att öka psoriatisk inflammation. Flera biologiska läkemedel utvecklas nu för behandling av plack-psoriasis. I detta arbete har fokus lagts på två av dem, sekukinumab som är en IL-17A hämmare och ustekinumab, som är en IL-12 och IL-23 hämmare. Syfte: Syftet med arbetet är att undersöka effektivitet av sekukinumab vid behandling av plack-psoriasis. Vidare undersöks även hur behandling av plack-psoriasis med sekukinumab skiljer sig från behandling med ustekinumab gällande minskning av plack-psoriasis. Metod: Detta arbete är en litteraturstudie som inkluderar fem vetenskapliga artiklar som baserades på randomiserade kontrollerade studier som sponsrades av läkemedelsföretag.  Resultat: Resultatet av de fem studier visar att behandling med hjälp av sekukinumab 300 mg och 150 mg var mer effektiv än behandling med ustekinumab 45/90 mg, enligt PASI 75, PASI 90 och PASI 100. Diskussion: Alla fem studierna var dubbel-blinda randomiserade kontrollerade studier vilket leder till säkra och tillförlitliga resultat. Däremot var samtliga studier sponsrade av läkemedelsföretag vilket kan leda till att positiv effekt beskrivs i större utsträckning för att kunna sälja sin produkt.  Slutsats: Sekukinumab 300 mg och 150 mg är signifikant mer effektiv än placebo och signifikant mer effektiv än ustekinumab 45/90 mg vid behandling av medelsvår och svår plack-psoriasis. / Introduction: Psoriasis is a chronic inflammatory systemic disease that mainly affects the skin and joints. Due to the very rapid growth of skin cells, psoriasis causes rashes on the skin. One of the most common types of psoriasis is plaque psoriasis which is characterized by larger than 0.5 cm in diameter round scaly skin rash that itches. The mechanism behind plaque psoriasis is mediated by T cells and dendritic cells, which are an important part of the immune system. Stimulation of these immune cells leads to the release of the following proinflammatory cytokines such as IL-17, IFN-γ, TNF and IL-22. These cytokines exert their effect on keratinocytes by increasing psoriatic inflammation.  Several biological drugs are now being developed for the treatment of plaque psoriasis. In this study, the focus has been on two of them, secukinumab which is an IL-17A inhibitor and ustekinumab, which is an IL-12 and IL-23 inhibitor. Purpose: The purpose of this study is to investigate the efficacy of secukinumab in the treatment of plaque psoriasis. Furthermore, it is also investigated if the treatment of plaque psoriasis with secukinumab differs from treatment with ustekinumab regarding reduction of plaque psoriasis. Method: This work is a literature study that includes five scientific articles based on randomized controlled trials sponsored by pharmaceutical companies.  Results: The results of the five studies show that treatment with secukinumab 300 mg and 150 mg was more effective than treatment with ustekinumab 45/90 mg, according to PASI 75, PASI 90 and PASI 100. Discussion: All five studies were double-blind randomized controlled trials leading to safe and reliable results. On the other hand, all studies were sponsored by pharmaceutical companies, which may lead to a positive effect being described to a greater extent in order to be able to sell their product. Conclusion: Secukinumab 300 mg and 150 mg are significantly more effective than placebo and significantly more effective than ustekinumab 45/90 mg in the treatment of moderate to severe plaque psoriasis.

Hepatitis B virus (HBV) vaccination is recommended for individuals with hepatitis C virus (HCV) infection given their shared risk factors and increased liver-related morbidity and mortality upon super-infection. Vaccine responses in this setting are often blunted, with poor response rates to HBV vaccinations in chronically HCV-infected individuals compared to healthy subjects. In this study, we investigated the role of T cell immunoglobulin mucin domain-3 (Tim-3)-mediated immune regulation in HBV vaccine responses during HCV infection. We found that Tim-3, a marker for T cell exhaustion, was over-expressed on monocytes, leading to a differential regulation of IL-12/IL-23 production which in turn TH17 cell accumulation, in HCV-infected HBV vaccine non-responders compared to HCV-infected HBV vaccine responders or healthy subjects (HS). Importantly, ex vivo blockade of Tim-3 signaling corrected the imbalance of IL-12/IL-23 as well as the IL-17 bias observed in HBV vaccine non-responders during HCV infection. These results suggest that Tim-3-mediated dysregulation of innate to adaptive immune responses is involved in HBV vaccine failure in individuals with chronic HCV infection, raising the possibility that blocking this negative signaling pathway might improve the success rate of HBV immunization in the setting of chronic viral infection.

Hepatitis B virus (HBV) vaccination is recommended for individuals with hepatitis C virus (HCV) infection given their shared risk factors and increased liver-related morbidity and mortality upon super-infection. Vaccine responses in this setting are often blunted, with poor response rates to HBV vaccinations in chronically HCV-infected individuals compared to healthy subjects. In this study, we investigated the role of T cell immunoglobulin mucin domain-3 (Tim-3)-mediated immune regulation in HBV vaccine responses during HCV infection. We found that Tim-3, a marker for T cell exhaustion, was over-expressed on monocytes, leading to a differential regulation of IL-12/IL-23 production which in turn TH17 cell accumulation, in HCV-infected HBV vaccine non-responders compared to HCV-infected HBV vaccine responders or healthy subjects (HS). Importantly, ex vivo blockade of Tim-3 signaling corrected the imbalance of IL-12/IL-23 as well as the IL-17 bias observed in HBV vaccine non-responders during HCV infection. These results suggest that Tim-3-mediated dysregulation of innate to adaptive immune responses is involved in HBV vaccine failure in individuals with chronic HCV infection, raising the possibility that blocking this negative signaling pathway might improve the success rate of HBV immunization in the setting of chronic viral infection.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18684号 / 医博第3956号 / 新制||医||1007(附属図書館) / 31617 / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 伊達 洋至, 教授 竹内 理 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20084号 / 医博第4177号 / 新制||医||1018(附属図書館) / 33200 / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 山田 亮, 教授 椛島 健治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Inflammatory immune responses are regulated by T cell subsets that secrete specific panels of cytokines. While CD8+ T cells that secrete IFN- and cytotoxic molecules (Tc1 cells) are known to mediate antiviral immunity, IL-17-secreting CD8+ T (Tc17) cells have only recently been described and the development and function of these cells has not been clearly examined. Using in vitro T cell cultures and mice deficient in transcription factors regulating lineage development, we defined Tc17 development and function. Similar to IL-17 secretion from CD4 T cells, IL-17 secretion from Tc17 cells is dependent on the transcription factor Stat3 and inhibited by Stat1. Expression of transcription factors important for Tc1 function, T-bet and Eomesodermin (Eomes), is reduced in Tc17 cells and consistent with this, Tc17 cells are non-cytotoxic in vitro. However, Tc17 cells are unstable and switch to cytotoxic IFN- producing cells when exposed to a Tc1 inducing cytokine, IL-12. Overexpression of the lineage promoting transcription factors T-bet and Eomes is unable to induce a Tc1 phenotype in Tc17 cells and Stat3 is also unable to switch Tc1 cells into Tc17 cells, suggesting additional signals are involved in CD8 T cell lineage commitment. In vivo, Tc17 cells are induced by vaccinia virus, dependant on Stat3, and are capable of mediating antiviral immunity. Tc17 cells acquire an IFN--secreting phenotype after encounter with virus in vivo, however, viral clearance by Tc17 cells is independent of IFN-. Instead, viral clearance is correlated with a gain in T-bet expression and cytotoxic function in Tc17 cells which have encountered virus. The development of anti-viral activity independent of IFN-, suggests that Tc17 cells may mediate anti-viral immunity through novel mechanisms that depend on the ability of Tc17 cells to acquire other phenotypes.

No description available.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24994号 / 医博第5028号 / 新制||医||1069(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 上野 英樹, 教授 椛島 健治, 教授 濵﨑 洋子 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM