21-Hydroxylase-Specific CD8+ T Cells in Autoimmune Addison’s Disease Are Restricted by HLA-A2 and HLA-C7 Molecules

Objectives: CD8+ T cells targeting 21-hydroxylase (21OH) are presumed to play a central role in the destruction of adrenocortical cells in autoimmune Addison’s disease (AAD). Earlier reports have suggested two immunodominant CD8+ T cell epitopes within 21OH: LLNATIAEV (21OH342-350), restricted by HLA-A2, and EPLARLEL (21OH431-438), restricted by HLA-B8. We aimed to characterize polyclonal CD8+ T cell responses to the proposed epitopes in a larger patient cohort with AAD. Methods: Recombinant fluorescent HLA-peptide multimer reagents were used to quantify antigen-specific CD8+ T cells by flow cytometry. Interferon-gamma (IFNγ) Elispot and biochemical assays were used to functionally investigate the 21OH-specific T cells, and to map the exactly defined epitopes of 21OH. Results: We found a significantly higher frequency of HLA-A2 restricted LLNATIAEV-specific cells in patients with AAD than in controls. These cells could also be expanded in vitro in an antigen specific manner and displayed a robust antigen-specific IFNγ production. In contrast, only negligible frequencies of EPLARLEL-specific T cells were detected in both patients and controls with limited IFNγ response. However, significant IFNγ production was observed in response to a longer peptide encompassing EPLARLEL, 21OH430-447, suggesting alternative dominant epitopes. Accordingly, we discovered that the slightly offset ARLELFVVL (21OH434-442) peptide is a novel dominant epitope restricted by HLA-C7 and not by HLA-B8 as initially postulated. Conclusion: We have identified two dominant 21OH epitopes targeted by CD8+ T cells in AAD, restricted by HLA-A2 and HLA-C7, respectively. To our knowledge, this is the first HLA-C7 restricted epitope described for an autoimmune disease.publishedVersio

Försvarad demokrati? : -En analys av diskurserna kring FRA-lagens legitimering.

Försvarad demokrati är ett arbete som genom en diskursanalys tar sig en närmare titt på debatten år 2008 om en utökad FRA-lag med sikte på att kritiskt analysera hur partierna med hjälp utav olika diskurser behandlar och vrider begrepp för att få dem att överstämma med den egna idén om hur vi bör förhålla oss till hotet. Arbetet kommer också reflektera över hur vi i en allt mer flytande modern värld försöker gör det flytande och okända fast för att på så sätt få någon typ utav kontroll över det samhälle som vi skapat oss. Genom att belysa de politiska diskurserna kring hot och demokrati i debatten om en utökad FRA-lag bidrar arbetet till att skapa en förståelse kring hur människor i en demokrati med demokratiska ideal, så som integritet samt tryck- och yttrandefrihet, genom relationen till hot accepterar att bli systematiskt och storskaligt övervakade utav sin egen stat. Därav också övervakade av sin egen demokrati.

Analysis of cellular and humoral immune responses against cytomegalovirus in patients with autoimmune Addison’s disease

Background. Autoimmune Addison’s disease (AAD) is caused by multiple genetic and environmental factors. Variants of genes encoding immunologically important proteins such as the HLA molecules are strongly associated with AAD, but any environmental risk factors have yet to be defined. We hypothesized that primary or reactivating infections with cytomegalovirus (CMV) could represent an environmental risk factor in AAD, and that CMV specific CD8+ T cell responses may be dysregulated, possibly leading to a suboptimal control of CMV. In particular, the objective was to assess the HLA-B8 restricted CD8+ T cell response to CMV since this HLA class I variant is a genetic risk factor for AAD. Methods. To examine the CD8+ T cell response in detail, we analyzed the HLA-A2 and HLA-B8 restricted responses in AAD patients and healthy controls seropositive for CMV antibodies using HLA multimer technology, IFN-γ ELISpot and a CD107a based degranulation assay. Results. No differences between patients and controls were found in functions or frequencies of CMV-specific T cells, regardless if the analyses were performed ex vivo or after in vitro stimulation and expansion. However, individual patients showed signs of reactivating CMV infection correlating with poor CD8+ T cell responses to the virus, and a concomitant upregulation of interferon regulated genes in peripheral blood cells. Several recently diagnosed AAD patients also showed serological signs of ongoing primary CMV infection. Conclusions. CMV infection does not appear to be a major environmental risk factor in AAD, but may represent a precipitating factor in individual patients

Peripheral blood cells from patients with autoimmune Addison's disease poorly respond to interferons in vitro, despite elevated serum levels of interferon-inducible chemokines

Autoimmune Addison's disease (AAD) is a disorder caused by an immunological attack on the adrenal cortex. The interferon (IFN)-inducible chemokine CXCL10 is elevated in serum of AAD patients, suggesting a peripheral IFN signature. However, CXCL10 can also be induced in adrenocortical cells stimulated with IFNs, cytokines, or microbial components. We therefore investigated whether peripheral blood mononuclear cells (PBMCs) from AAD patients display an enhanced propensity to produce CXCL10 and the related chemokine CXCL9, after stimulation with type I or II IFNs or the IFN inducer poly (I:C). Although serum levels of CXCL10 and CXCL9 were significantly elevated in patients compared with controls, IFN stimulated patient PBMC produced significantly less CXCL10/CXCL9 than control PBMC. Low CXCL10 production was not significantly associated with medication, disease duration, or comorbidities, but the low production of poly (I:C)-induced CXCL10 among patients was associated with an AAD risk allele in the phosphatase nonreceptor type 22 (PTPN22) gene. PBMC levels of total STAT1 and -2, and IFN-induced phosphorylated STAT1 and -2, were not significantly different between patients and controls. We conclude that PBMC from patients with AAD are deficient in their response to IFNs, and that the adrenal cortex itself may be responsible for the increased serum levels of CXCL10

MOESM2 of Analysis of cellular and humoral immune responses against cytomegalovirus in patients with autoimmune Addison’s disease

Additional file 2: Figure S2. Gating strategy for flow cytometric analysis of dextramer-stained PBMC from AAD patients and healthy controls. Dot plots show the gating strategy used to determine the levels of dextramer positive CD8+ T cells. P1: singlet selection to avoid cellular doublets. R1: Positive gating of CD8+ population (using APC-conjugated antibodies) in P1. Exclusion of CD4+ T cells, CD14+ monocytes and CD19+ B cells (using FITC-conjugated antibodies), to avoid unspecific dextramer binding. P2: Positive gating on R1 population, excluding dead cells. R2: Positive gating on P2 population, selecting CMV-dextramer (PE-conjugated) positive CD8+ T cells

MOESM4 of Analysis of cellular and humoral immune responses against cytomegalovirus in patients with autoimmune Addison’s disease

Additional file 4: Figure S4. Mean fluorescent intensity (MFI) of degranulating CMV-specific CD8+ T cells in AAD patients and controls. The specific mean fluorescent intensity (ΔMFI) of CMV stimulated CD107a positive cells (after subtracting the MFI of unstimulated cells) was compared between patients (n = 7) and controls (n = 10). Unpaired t test was used to test for statistical differences between patients and controls, but none were found. The bars display the mean for the whole group

Altered Immune Activation and IL-23 Signaling in Response to Candida albicans in Autoimmune Polyendocrine Syndrome Type 1

ObjectiveAutoimmune polyendocrine syndrome type 1 (APS-1) is a rare, childhood onset disease caused by mutations in the autoimmune regulator (AIRE) gene. Chronic mucocutaneous candidiasis (CMC) is one of the three major disease components and is, to date, mainly explained by the presence of neutralizing auto-antibodies against cytokines [interleukin (IL)-17A, IL-17F, and IL-22] from T helper 17 cells, which are critical for the protection against fungal infections. However, patients without current auto-antibodies also present CMC and we, therefore, hypothesized that other immune mechanisms contribute to CMC in APS-1.MethodsWhole blood was stimulated with Candida albicans (C. albicans) in a standardized assay, and immune activation was investigated by analyzing 46 secreted immune mediators. Then, peripheral blood mononuclear cells were stimulated with curdlan, a Dectin-1 agonist and IL-23 inducer, and the IL-23p19 response in monocytes was analyzed by flow cytometry.ResultsWe found an altered immune response in APS-1 patients compared with healthy controls. Patients fail to increase the essential ILs, such as IL-2, IL-17A, IL-22, and IL-23, when stimulating whole blood with C. albicans. A significantly altered IL-23p19 response was detected in patients’ monocytes upon stimulation with curdlan.ConclusionAPS-1 patients have an altered immune response to C. albicans including a dysregulation of IL-23p19 production in monocytes. This probably contributes to the selective susceptibility to CMC found in the majority of patients

21-Hydroxylase-Specific CD8+ T Cells in Autoimmune Addison’s Disease Are Restricted by HLA-A2 and HLA-C7 Molecules

Objectives: CD8+ T cells targeting 21-hydroxylase (21OH) are presumed to play a central role in the destruction of adrenocortical cells in autoimmune Addison’s disease (AAD). Earlier reports have suggested two immunodominant CD8+ T cell epitopes within 21OH: LLNATIAEV (21OH342-350), restricted by HLA-A2, and EPLARLEL (21OH431-438), restricted by HLA-B8. We aimed to characterize polyclonal CD8+ T cell responses to the proposed epitopes in a larger patient cohort with AAD. Methods: Recombinant fluorescent HLA-peptide multimer reagents were used to quantify antigen-specific CD8+ T cells by flow cytometry. Interferon-gamma (IFNγ) Elispot and biochemical assays were used to functionally investigate the 21OH-specific T cells, and to map the exactly defined epitopes of 21OH. Results: We found a significantly higher frequency of HLA-A2 restricted LLNATIAEV-specific cells in patients with AAD than in controls. These cells could also be expanded in vitro in an antigen specific manner and displayed a robust antigen-specific IFNγ production. In contrast, only negligible frequencies of EPLARLEL-specific T cells were detected in both patients and controls with limited IFNγ response. However, significant IFNγ production was observed in response to a longer peptide encompassing EPLARLEL, 21OH430-447, suggesting alternative dominant epitopes. Accordingly, we discovered that the slightly offset ARLELFVVL (21OH434-442) peptide is a novel dominant epitope restricted by HLA-C7 and not by HLA-B8 as initially postulated. Conclusion: We have identified two dominant 21OH epitopes targeted by CD8+ T cells in AAD, restricted by HLA-A2 and HLA-C7, respectively. To our knowledge, this is the first HLA-C7 restricted epitope described for an autoimmune disease