| 1. |
- Ingelsson, Björn, 1983-, et al.
(författare)
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Lymphocytes eject interferogenic mitochondrial DNA webs in response to CpG and non-CpG oligodeoxynucleotides of class C
- 2018
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - Washington, DC, United States : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 115:3, s. E478-E487
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Tidskriftsartikel (refereegranskat)abstract
- Circulating mitochondrial DNA (mtDNA) is receiving increasing attention as a danger-associated molecular pattern in conditions such as autoimmunity, cancer, and trauma. We report here that human lymphocytes [B cells, T cells, natural killer (NK) cells], monocytes, and neutrophils derived from healthy blood donors, as well as B cells from chronic lymphocytic leukemia patients, rapidly eject mtDNA as web filament structures upon recognition of CpG and non-CpG oligodeoxynucleotides of class C. The release was quenched by ZnCl2, independent of cell death (apoptosis, necrosis, necroptosis, autophagy), and continued in the presence of TLR9 signaling inhibitors. B-cell mtDNA webs were distinct from neutrophil extracellular traps concerning structure, reactive oxygen species (ROS) dependence, and were devoid of antibacterial proteins. mtDNA webs acted as rapid (within minutes) messengers, priming antiviral type I IFN production. In summary, our findings point at a previously unrecognized role for lymphocytes in antimicrobial defense, utilizing mtDNA webs as signals in synergy with cytokines and natural antibodies, and cast light on the interplay between mitochondria and the immune system.
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| 2. |
- Lanemo Myhrinder, Anna, 1975-, et al.
(författare)
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A new perspective : molecular motifs on oxidized LDL, apoptotic cells, and bacteria are targets for chronic lymphocytic leukemia antibodies
- 2008
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 111:7, s. 3838-3848
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Tidskriftsartikel (refereegranskat)abstract
- The restricted immunoglobulin (Ig) repertoire found in B-cell chronic lymphocytic leukemia (CLL) implies a role for antigen(s) in the leukemogenesis. The nature of the antigens has, however, not been characterized, although examples of autoantigens have been demonstrated. We have analyzed a panel of 28 CLL cell lines and primary cultures, producing monoclonal Ig with different Ig heavy-chain variable region gene usage and mutational status, including several complementarity determining region 3 homology subset members. Using mass-spectrometry, immunoassays, or protein macroarrays, we have discovered novel antigens binding to CLL Igs. These antigens included cytoskeletal proteins vimentin, filamin B, and cofilin-1, but also phosphorylcholine-containing antigens (eg, Streptococcus pneumoniae polysaccharides and oxidized low-density lipoprotein [oxLDL]). Additional new antigens identified were cardiolipin and proline-rich acidic protein-1. Remarkably, these antigens represent molecular motifs exposed on apoptotic cells/blebs and bacteria, and several CLL Igs bound to apoptotic Jurkat cells. In conclusion, these intriguing data, showing a limited target structure recognition, indicate that CD5(+) CLL B cells are derived from a cell compartment that produces "natural antibodies," which may be instrumental in elimination and scavenging of apoptotic cells and pathogenic bacteria.
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| 3. |
- Blokzijl, Andries, et al.
(författare)
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Single Chain Antibodies as Tools to Study transforming growth factor--Regulated SMAD Proteins in Proximity Ligation-Based Pharmacological Screens
- 2016
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Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 15:6, s. 1848-1856
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Tidskriftsartikel (refereegranskat)abstract
- The cellular heterogeneity seen in tumors, with subpopulations of cells capable of resisting different treatments, renders single-treatment regimens generally ineffective. Accordingly, there is a great need to increase the repertoire of drug treatments from which combinations may be selected to efficiently target sets of pathological processes, while suppressing the emergence of resistance mutations. In this regard, members of the TGF- signaling pathway may furnish new, valuable therapeutic targets. In the present work, we developed in situ proximity ligation assays (isPLA) to monitor the state of the TGF- signaling pathway. Moreover, we extended the range of suitable affinity reagents for this analysis by developing a set of in-vitro-derived human antibody fragments (single chain fragment variable, scFv) that bind SMAD2 (Mothers against decapentaplegic 2), 3, 4, and 7 using phage display. These four proteins are all intracellular mediators of TGF- signaling. We also developed an scFv specific for SMAD3 phosphorylated in the linker domain 3 (p179 SMAD3). This phosphorylation has been shown to inactivate the tumor suppressor function of SMAD3. The single chain affinity reagents developed in the study were fused tocrystallizable antibody fragments (Fc-portions) and expressed as dimeric IgG-like molecules having Fc domains (Yumabs), and we show that they represent valuable reagents for isPLA. Using these novel assays, we demonstrate that p179 SMAD3 forms a complex with SMAD4 at increased frequency during division and that pharmacological inhibition of cyclin-dependent kinase 4 (CDK4)(1) reduces the levels of p179SMAD3 in tumor cells. We further show that the p179SMAD3-SMAD4 complex is bound for degradation by the proteasome. Finally, we developed a chemical screening strategy for compounds that reduce the levels of p179SMAD3 in tumor cells with isPLA as a read-out, using the p179SMAD3 scFv SH544-IIC4. The screen identified two kinase inhibitors, known inhibitors of the insulin receptor, which decreased levels of p179SMAD3/SMAD4 complexes, thereby demonstrating the suitability of the recombinant affinity reagents applied in isPLA in screening for inhibitors of cell signaling.
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| 4. |
- Hellqvist, Eva, 1978-, et al.
(författare)
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Myelin protein zero is naturally processed in IgM MGUS B cells : Aberrant triggering of patient T cells
- 2010
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Ingår i: Haematologica. - : Ferrata Storti Foundation (Haematologica). - 0390-6078 .- 1592-8721. ; 95:4, s. 627-636
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Tidskriftsartikel (refereegranskat)abstract
- Background and Objectives: Monoclonal gammopathy of undetermined significance (MGUS) of IgM isotype is a condition with clonally expanded B cells, recently suggested having an infectious origin. MGUS is frequently associated with polyneuropathy and antibodies against myelin protein zero (P0), whereas the role of the T cells remains largely unknown. Here we have analyzed P0-specific B cells, as antigen-presenting cells, and their capacity to activate T helper cells. Design and Methods: We used a well-characterized MGUS-derived B cell line, TJ2, expressing anti-P0 IgM. The ability of TJ2 cells to bind, endocytose, process, and present P0 was investigated by receptor-clustering and immunofluorescence. The activation of P0-specific autologous T cells was studied by measuring IL2 and IFNγ with flow cytometry, immunobeads, and ELISPOT. Results: Surface-receptor clustering and endocytosis of receptor-ligand (IgM/P0) complexes were pronounced after P0 exposure. Naturally processed or synthetic P0 peptide (194-208)-pulsed TJ2 cells significantly induced IL2 secretion from autologous T cells compared to control antigen pulsed cells (p<0 .001). The numbers of IFNγ producing T helper cells, including CD4+/CD8+ cells, were also significantly increased (p=0.0152). Affinity-isolated naturally processed myelin peptides were potent IFNγ stimulators for autologous PBMCs, but not for control PBMCs. Interpretation and conclusions: We show for the first time that myelin P0 is naturally processed in IgM MGUS B cells, acting as aberrant antigen-presenting cells in activation of patients T helper cells. Our findings cast new light on the important role of autoreactive P0-specific B cells in he induction of the pathogenic T cell responses found in nerve lesions of MGUS patients with peripheral neuropathy.
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| 5. |
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| 6. |
- Jönsson-Videsäter, Kerstin, et al.
(författare)
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Selenite-induced apoptosis in doxorubicin-resistant cells and effects on the thioredoxin system.
- 2004
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Ingår i: Biochemical Pharmacology. - : Elsevier BV. - 0006-2952. ; 67:3, s. 513-522
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Tidskriftsartikel (refereegranskat)abstract
- Selenium treatment of the doxorubicin-resistant cell line, U-1285dox, derived from human small cell carcinoma of the lung, resulted in massive apoptosis. This effect appeared maximal at 2 days after addition of selenite. The apoptosis was caspase-3 independent as revealed by Western blot analysis, activity measurement and by using caspase inhibitors. Induction of apoptosis was significantly more pronounced and occurred after addition of lower concentrations of selenite in the doxorubicin-resistant cells compared to the parental doxorubicin-sensitive cells. High levels of selenite caused necrosis in the doxorubicin-sensitive cells. Analysis of enzymatic activity (insulin reduction) of thioredoxin reductase (TrxR) and TrxR protein concentration, measured by ELISA, revealed increasing activity and protein levels after treatment with increasing concentrations of selenium. Maximum relative increase was induced up to 1 μM in both sublines and at this selenium level the concentrations of TrxR measured as insulin reducing activity or ELISA immunoreactivity were nearly identical. Increasing concentrations of selenite up to 10 μM resulted in increased activity and concentration of TrxR in the sensitive subline but decreasing levels in the resistant subline. The level of truncated Trx (tTrx) was higher in the resistant U-1285dox cells but the level did not change with increasing selenite concentrations. Our results demonstrate pronounced selective selenium-mediated apoptosis in therapy-resistant cells and suggest that redox regulation through the thioredoxin system is an important target for cancer therapy.
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| 7. |
- Raja, Erna, et al.
(författare)
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The protein kinase LKB1 negatively regulates bone morphogenetic protein receptor signaling
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:2, s. 1120-1143
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Tidskriftsartikel (refereegranskat)abstract
- The protein kinase LKB1 regulates cell metabolism and growth and is implicated in intestinal and lung cancer. Bone morphogenetic protein (BMP) signaling regulates cell differentiation during development and tissue homeostasis. We demonstrate that LKB1 physically interacts with BMP type I receptors and requires Smad7 to promote downregulation of the receptor. Accordingly, LKB1 suppresses BMP-induced osteoblast differentiation and affects BMP signaling in Drosophila wing longitudinal vein morphogenesis. LKB1 protein expression and Smad1 phosphorylation analysis in a cohort of non-small cell lung cancer patients demonstrated a negative correlation predominantly in a subset enriched in adenocarcinomas. Lung cancer patient data analysis indicated strong correlation between LKB1 loss-of-function mutations and high BMP2 expression, and these two events further correlated with expression of a gene subset functionally linked to apoptosis and migration. This new mechanism of BMP receptor regulation by LKB1 has ramifications in physiological organogenesis and disease.
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| 8. |
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| 9. |
- Sahaf, Bita, et al.
(författare)
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Thioredoxin Expression and Localization in Human Cell Lines : Detection of Full-Length and Truncated Species
- 1997
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Ingår i: Experimental Cell Research. - : Elsevier BV. - 0014-4827 .- 1090-2422. ; 236:1, s. 181-192
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Tidskriftsartikel (refereegranskat)abstract
- Thioredoxin (Trx) is an intracellular multifunctional 12-kDa protein with a reduction/oxidation (redox) active disulfide constitutively expressed by most cells of the human body. Trx can also be released by cells such as lymphocytes upon activation or oxidative stress exposure and exert a cocytokine and cytoprotective activity. In addition, a truncated 10-kDa form of Trx has been reported. In order to better understand the function of full-length and truncated Trx, we have produced, for the first time, specific monoclonal antibodies, which can discriminate between the two forms. Using these novel antibodies, designated αTrx1 to αTrx4, a panel of cell lines derived from human B and T lymphocytes, monocytes, granulocytes, and melanomas was analyzed by immunochemical techniques. The cellular distribution differed between the two forms. All lines contained full-length Trx, also located to a minor extent on the cell surface. One exception was the melanoma cell line FM28.4, which did not show any Trx expression. Truncated Trx was present in most cells in minimal amounts only, whereas the monocytic cell lines THP-1 and U-937 expressed high amounts on the cell surface, as shown by flow cytometric analysis of living cells and confocal laser-scanning microscopy. The biological importance and function of the short versus long forms of Trx as detected by the antibodies are discussed.
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| 10. |
- Simonsson, Per, 1974-
(författare)
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Bidrag till familjens ekonomiska historia : Inflytande över konsumtionen inom svenska hushåll under 1900-talet
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation deals with consumption in Swedish households between 1913 and 2001. More specifically, it asks whose resources matter most in determining consumption patterns. As a second question, the dissertation also attempts to establish whether the fact that simple covariance between a spouse’s background variables implies that the spouse has any influence at all over the household’s consumption decisions. The theoretical background is mostly drawn from literature regarding intra-household allocations: on the one hand cooperative game theory and on the other hand sociological theory. Cooperative game theory establishes influence, say or power within the household as a function of the marriage’s or cohabitation’s alternative cost, i.e., the difference between the utility level for a married or cohabiting person as opposed to a single person. Sociological theory considers the contribution one makes to the total level of utility in the household, whether in the form of monetary income, household work or as something else. This is in part conceptualized as a difference between exit and voice. The dissertation’s statistical analysis uses three surveys of household expenditure conducted in 1913, 1952 and 1999-2001. They give us an excellent picture of what they actually purchased during that year. The sample sizes are 552, 596 and 3,501, respectively. The dissertation’s main result is that human capital is a previously underestimated determinant of influence in consumption decisions. As the female stock of human capital increases, so does her influence over the household’s consumption decisions. In an attempt to determine the level of democracy within households, the dissertation uses a complementary data source: a questionnaire called “The Swedish People 1955”. Here, one of the questions directed to females was whether they checked with their husbands before deciding on a purchase, as a measure of intra-household democracy. This was then regressed upon the female share of total income, ideological position and two forms of human capital, one general and one for household work. Both forms of human capital lead to democratic households, which is taken to mean that human capital is important not only because it increases labor opportunities in the event of divorce (exit) but also because it increases female voice.
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