| 1. |
- Harkonen, T, et al.
(författare)
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Enterovirus infection may induce humoral immune response reacting with islet cell autoantigens in humans
- 2003
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 69:3, s. 426-440
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Tidskriftsartikel (refereegranskat)abstract
- Molecular mimicry is one of the mechanisms by which enterovirus infections have been postulated to have a role in the pathogenesis of type 1 diabetes. Immunogenic epitopes in enterovirus capsid protein VP1 and procapsid protein VP0 have sequence similarities with diabetes-associated epitopes in tyrosine phosphatase IA-2/IAR and heat shock protein 60. In the present study, documented enterovirus infection was shown to induce humoral responses, that in 7% and 1% of patients cross-reacted with the known diabetes-associated epitopes in tyrosine phosphatase IAR and heat shock protein 60, respectively. In contrast, none of the children vaccinated against poliomyelitis had antibodies to the diabetes-associated epitope of tyrosine phosphatases IA-2/IAR. The antibody response studied in serum samples from six patients with coxsackievirus A9 infection was mainly targeted to capsid protein VP1. Coxsackievirus A9 infection induced antibodies cross-reacted with one epitope in heat shock protein 60, but not with epitopes derived from other autoantigens. Most diabetic children had high levels of antibodies to both coxsackievirus and poliovirus derived VP1 peptides but the pattern of reactivity did not differ from that seen in healthy children. The reactivity of linear epitopes derived from autoantigens was low in general and associated with the presence of multiple autoantibodies in the patients. Some linear auto-epitopes derived from tyrosine phosphatase IA-2, glutamic acid decarboxylase 65, preproinsulin, and heat shock protein 60 were recognized by sera from diabetic patients, but not by sera from healthy children. In conclusion, enteroviruses may induce immune responses that react with islet cell autoantigens, which is a concern when a putative inactivated enterovirus vaccine is considered.
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| 2. |
- Paananen, A., et al.
(författare)
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Interaction between cellulose and xylan : An atomic force microscope and quartz crystal microbalance study
- 2004
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Ingår i: Hemicellulose. - 0841238421 ; , s. 269-290
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Konferensbidrag (refereegranskat)abstract
- The atomic force microscope (AFM) colloidal probe technique has been used to investigate forces between cellulose beads as well as cellulose beads and mica in aqueous solution, and the interaction between cellulose surfaces in xylan solutions. Several observations of the behaviour of the cellulose beads were made. Swelling of the beads in aqueous solutions is rather slow. Thus, it is important to let the beads equilibrate before measurements. The beads are somewhat compressed when forced together to constant compliance, but relax back to their original shape in a few minutes. A long-range electrostatic repulsion between cellulose and mica occurs on approach. The xylan concentration in solution affects the forces between two cellulose surfaces. When the concentration increases from 10-100 mg/l more xylan adsorbs slowly and irreversibly on the cellulose leading to an increasingly long-range and stronger repulsion between the surfaces on approach. Adhesion between the layers is very low and seems to be due to entanglement of polymer chains. Studies of the adsorption of xylan (100 mg/l) on cellulose films with a quartz crystal microbalance with dissipation (QCM-D) verify that a thick, water-swollen layer of xylan is formed by slow adsorption. It has been proposed that adsorbed xylan on fibre surfaces increases paper strength. We conclude that this must be associated with the behaviour of the adsorbed layers of xylan on drying.
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