| 1. |
- Truedsson, L, et al.
(författare)
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Protein HC-IgA complexes carry antibody activities
- 1988
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 0300-9475 .- 1365-3083. ; 27:2, s. 201-208
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Tidskriftsartikel (refereegranskat)abstract
- Polyclonal protein HC-IgA complexes (HC-IgA) were isolated from two different serum pools. Their hydrodynamic volumes were found to be slightly greater than that of monomeric IgA but less than that of dimeric IgA. Sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis of reduced and carboxymethylated complexes followed by immunoblotting showed that the complexes contained normal light and heavy Ig chains, and one polypeptide chain with Mr = 90,000, which carried both IgA alpha chain and protein HC epitopes. Enzyme-linked immunosorbent assays (ELISA) demonstrated that the isolated HC-IgA carried about 0.1 and 4%, respectively, of the antibody activities against one carbohydrate antigen (Yersinia enterocolitica serotype 0:3 lipopolysaccharide) and one protein antigen (rabbit IgG, i.e. antigen for rheumatoid factors) of the IgA populations of the two serum pools. HC-IgA with rheumatoid factor activity could also be demonstrated in the unfractionated serum pool. The binding of HC-IgA in the ELISA was not mediated through its protein HC part. The present observations show that HC-IgA carries antibody activities and constitutes a unique class of IgA complexes, since it does not dissociate under denaturating conditions after reduction. It may represent a further biological potential of the humoral immune system.
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| 2. |
- Mårtensson, Inga-Lill, 1957, et al.
(författare)
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The Pre-B Cell Receptor; Selecting for or against Autoreactivity
- 2012
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 0300-9475 .- 1365-3083. ; 76:3, s. 256-262
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Forskningsöversikt (refereegranskat)abstract
- Antibodies represent a crucial component of humoral immunity as protection against invading pathogens, to which they bind and thereby trigger mechanisms that lead to the disposal of the pathogen. Antibodies are assembled from Ig heavy chains (HCs) and light chains (LCs) and are found in both a secreted and a membrane-bound form, termed B cell receptors (BCRs), where the latter allows the ‘right’ B cell to respond upon recognition of its cognate antigen. The antibody repertoire is almost unlimited because of a process in which germ line V(D)J gene segments, encoding the variable (antigen-binding) region of the antibody HCs and LCs, are recombined. As this process is random, it is apparent that it results in a vast variety of antibodies, those that recognize foreign but also those that recognize self- (auto-) antigens. Control mechanisms are, therefore, in place to ensure that as few autoreactive B cells as possible are allowed to proceed in development. This counter-selection takes place through various mechanisms and at several stages as the cells develop from pre-B cells to antibody-secreting plasma cells. At the first major checkpoint, at the pre-BI to pre-BII cell transition, antibody HCs assemble with the invariant surrogate LC (SLC) forming a pre-BCR. Herein, we will discuss the role of the pre-BCR in the selection at this stage, how a dysfunctional pre- BCR affects selection and its effects on later stages, and whether the pre-BCR selects for or against autoreactivity.
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- Andersen, Grethe, et al.
(författare)
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Quantitative measurement of the levels of melanocortin receptor subtype 1, 2, 3 and 5 and pro-opio-melanocortin peptide gene expression in subsets of human peripheral blood leucocytes
- 2005
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Ingår i: Scandinavian Journal of Immunology. - Oxford : Wiley. - 0300-9475 .- 1365-3083. ; 61:3, s. 279-284
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Tidskriftsartikel (refereegranskat)abstract
- Levels of the melanocortin receptor (MCR) 1, 2, 3 and 5 subtypes and pro-opio-melanocortin (POMC) protein mRNA were measured by the real-time quantitative reverse transcriptase polymerase chain reaction method in CD4+ T helper (Th) cells, CD8+ T cytotoxic cells, CD19+ B cells, CD56+ natural killer (NK) cells, CD14+ monocytes and CD15+ granulocytes from healthy donors. We found high levels of all of the MC1, 2, 3 and 5R subtype mRNA in Th cells and moderate levels in NK cells, monocytes and granulocytes. POMC peptide mRNA was found in all examined leucocyte subsets, but only low levels were present in granulocytes. Our findings suggest a co-ordinating role for MCR subtypes and their naturally occurring ligands in the co-operation between innate and adaptive immunity. Moreover, our findings are compatible with earlier finding of MCR-mediated tolerance induction in Th cells.
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| 7. |
- Bäckström, Fredrik, 1971, et al.
(författare)
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Absence of in vitro responses to type II collagen by splenocytes from arthritic BALB/c mice is possibly caused by intrinsic CD25+ regulatory cells.
- 2008
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Ingår i: Scandinavian journal of immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 67:4, s. 362-9
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Tidskriftsartikel (refereegranskat)abstract
- Collagen-induced arthritis-resistant BALB/c mice develop arthritis if a foreign protein is added to an emulsion of type II collagen (CII) and adjuvant. The IgG autoantibody activity to CII is increased, whereas no CII autoreactive T cells in vitro can be recorded. In this study, we have explored whether CD25+ cells inhibit T-cell autoreactivity to CII. We also followed the IgG anti-CII autoantibody activity and the IL-6 level in serum during the development of arthritis. BALB/c mice were coimmunized with bovine CII (BCII) and keyhole limpet haemocyanin (KLH) in complete Freund's adjuvant and boostered 3 weeks later. Control animals were immunized with either BCII or KLH. Sera were collected prior to and during the development of arthritis and examined for IgG anti-CII antibody activity and IL-6 content. When all BCII-KLH immunized mice had developed arthritis, splenocytes were prepared, with and without CD25+ cells, and tested for BCII reactivity in vitro. The serum IgG, IgG1 and IgG2a anti-CII antibody activities and the IL-6 level were significantly higher in BCII-KLH immunized mice than in BCII-immunized animals that failed to develop arthritis. The BCII-specific IL-2 secretion in vitro was significantly increased in CD25-depleted splenocyte cultures prepared from arthritic BCII-KLH-immunized mice. Development of arthritis in BALB/c mice induced by coimmunization with BCII/KLH results in increased levels of circulating IL-6 and IgG autoantibodies to CII. The arthritogenic BCII-KLH immunization potentiates BCII-specific IL-2 secretion by CD25-depleted splenocytes, but CD25+ cells hamper the outcome of their action, at least in vitro.
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| 8. |
- Bäckström, Fredrik, 1971, et al.
(författare)
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Induction of experimental arthritis in BALB/c mice by inclusion of a foreign protein in the collagen inoculum
- 2008
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 67:4, s. 322-8
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Tidskriftsartikel (refereegranskat)abstract
- The susceptibility of mice to collagen-induced arthritis (CIA) has, among other things, been linked to the major histocompatibility complex class II genes as well as other genes. This study was designed to examine the possibilities to establish CIA in low susceptible I-Ad (Balb/C) mice. Balb/C mice were immunized twice with bovine type II collagen (BCII) in complete Freund's adjuvant (CFA) containing the amount of Mycobacterium tuberculosis needed to induce CIA in low susceptible I-Ab (C57BL/6) mice. Some mice received the conceivable arthritogenic inoculum mixed with ovalbumin (OVA). Clinical arthritis was monitored. Antibody activity and T-cell reactivity to BCII were determined. Unexpectedly, only mice that were immunized with the BCII-OVA mixture developed arthritis. Combining BCII with another foreign protein, keyhole limpet hemocyanin, but not the self-protein mouse serum albumin, also triggered arthritis. Prior to the appearance of arthritis the serum levels of IgG autoantibodies to BCII were higher in the coimmunized mice than in the mice that were immunized with BCII alone. Yet, splenocytes stimulated in vitro with BCII did not proliferate or produce interferon-gamma. Immunization of Balb/c mice with an emulsion-containing CFA and BCII mixed with a foreign body, but not a self-protein, elevates the level of circulating autoantibodies to CII and subsequently induces arthritis.
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| 9. |
- Pullerits, Rille, 1969, et al.
(författare)
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Off-Trial Evaluation of the B cell-Targeting Treatment in the Refractory Cases of Antineutrophil Cytoplasmic Antibodies (ANCA)-Associated Vasculitis: Long-Term Follow-Up from a Single Centre.
- 2012
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Ingår i: Scandinavian journal of immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 76:4, s. 411-20
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to evaluate long-term clinical and immunological effects of anti-B cell treatment in patients with antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis refractory to conventional immunosuppressive treatment. Rituximab (RTX) was added to the ongoing immunosuppressive treatment in 29 patients with refractory ANCA-associated vasculitis. The disease activity was measured using Birmingham Vasculitis Activity Score/Wegener's granulomatosis (BVAS/WG score), and clinical laboratory variables were recorded. The median BVAS/WG score before treatment was 6 (IQR 3-8), and 28 patients (97%) had disease flare classified either severe (62%) or limited (34%). Six of 29 patients (21%) achieved a complete remission, and 12 (41%) had a treatment response with ≥50% decrease in BVAS/WG score at 6 months. Fourteen patients (64%) with kidney involvement achieved remission, and in seven patients (50%), no flare was seen during the follow-up period. Three patients had renal flare and were successfully re-treated with RTX. Seventeen patients had disease symptoms from airways and eyes at RTX initiation, whereas only 29% displayed ≥50% treatment response. Limited clinical improvement was seen in patients with endobronchial lesions and trachea-subglottic granulomatous disease. RTX is a potent therapeutic option for ANCA-associated vasculitis refractory to conventional treatment. Best response may be expected in patients with vasculitic manifestations.
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| 10. |
- Svensson, Alexandra, 1978, et al.
(författare)
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Enveloped virus but not bacteria block IL-13 responses in human cord blood T cells in vitro.
- 2012
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Ingår i: Scandinavian journal of immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 75:4, s. 409-18
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Tidskriftsartikel (refereegranskat)abstract
- Infections that occur early in life may have a beneficial effect on the immune system and thereby reduce the risk of allergen sensitization and/or allergic disease. It is not yet clear to what extent specific virus and/or bacteria can mediate this effect. The purpose of this study was to assess the role of virus and bacteria in CD4(+) T cell-derived cytokine production in newborns. We compared the effects of five bacteria (Staphlococcus aureus, Escherichia coli, Clostridium difficile, Lactobacillus rhamnosus and Bifidobacterium bifidus) and seven virus (adenovirus, coronavirus, cytomegalovirus, herpes simplex virus, influenza virus, morbillivirus and poliovirus) on the Th1/Th2 cytokine production in mixed lymphocyte reactions using CD4(+) T cells from cord blood cocultured with allogenic myeloid or plasmacytoid dendritic cells. When comparing the baseline cytokine production prior to microbial stimulation, we observed that cord plasmacytoid DC were stronger inducers of Th2 cytokines (IL-5 and IL-13) compared with cord myeloid DC and to adult DC. When adding microbes to these cultures, bacteria and virus differed in two major respects; Firstly, all enveloped viruses, but none of the bacteria, blocked Th2 (IL-13) production by cord CD4(+) cells. Secondly, all Gram-positive bacteria, but none of the virus, induced IL-12p40 responses, but the IL-12p40 responses did not affect Th1 cytokine production (IFN-γ). Instead, Th1 responses were correlated with the capacity to induce IFN-α secretion, which in cord cells were induced by S. aureus and influenza virus alone. These data imply that enveloped virus can deviate Th2 responses in human cord T cells.
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