| 1. |
- Hanson, L A, et al.
(författare)
-
Sensitization and development of tolerance via the gut.
- 1993
-
Ingår i: Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology. - 0905-6157. ; 4:3 Suppl, s. 16-20
-
Tidskriftsartikel (refereegranskat)
|
|
| 2. |
- Nilssen, D E, et al.
(författare)
-
B-cell activation in duodenal mucosa after oral cholera vaccination in IgA deficient subjects with or without IgG subclass deficiency.
- 1993
-
Ingår i: Scandinavian journal of immunology. - 0300-9475. ; 38:2, s. 201-8
-
Tidskriftsartikel (refereegranskat)abstract
- Alterations in duodenal Ig-producing cells induced by two oral cholera vaccinations were studied by two-colour immunofluorescence in mucosal tissue sections from adults with selective IgA deficiency (IgAD), either with (n = 7) or without (n = 9) frequent infections, infection-prone patients with combined IgAD and IgG subclass deficiency (IgGSD) (n = 7), and normal control subjects (n = 11). The proportion of IgG-producing cells prior to immunization tended to be lower in the symptomatic IgAD subjects than in the clinically healthy ones. In the first subgroup the absolute number of IgG cells per intestinal length unit was significantly increased after immunization (P < 0.04), and this tendency was also observed in the healthy IgAD subjects (6/9) and in those with combined deficiency (5/7). Very few IgAD subjects responded with an increase of IgM-producing cells. The normal controls responded variably in all major immunocyte classes, in the order IgA > IgG > IgM. Compared with these controls, the patients with combined IgAD and IgGSD showed significantly increased IgG1 (P < 0.01) and reduced IgG2 (P < 0.006) proportions, which was in accordance with their serum subclass levels. Our study showed that oral cholera vaccination preferentially activates intestinal IgG-producing cells in IgAD subjects. This result agreed with data recently obtained by ELISPOT in the same patients with regard to antibody-forming cells specific for cholera toxin. Both methods suggested that IgG rather than IgM antibodies are elicited as compensation for a lacking IgA response. However, our overall results showed that intestinal B-cell activation is quite variable after oral cholera vaccination. Although such vaccination might be of importance for enhancing mucosal immunity also in IgAD patients, a concurrent gut disease could possibly be aggravated by IgG-mediated mucosal immunopathology in the absence of anti-inflammatory IgA antibodies.
|
|
| 3. |
|
|
| 4. |
- Bromander, A K, et al.
(författare)
-
Cholera toxin enhances alloantigen presentation by cultured intestinal epithelial cells.
- 1993
-
Ingår i: Scandinavian journal of immunology. - 0300-9475. ; 37:4, s. 452-8
-
Tidskriftsartikel (refereegranskat)abstract
- In the present study we show that cholera toxin (CT) strongly potentiates antigen presentation by intestinal epithelial cells, probably by enhancing co-stimulation. This was demonstrated in an allogeneic system using cells from the IEC-17 rat epithelial cell line as antigen presenting cells (APC). These cells were induced by optimal concentrations of IFN-gamma to express good amounts of Ia antigen and cultured for 24-48 h in the presence or absence of CT. Thereafter the cells were thoroughly washed and added to cultures containing MHC-incompatible spleen cells as responder cells. Epithelial cells exposed to CT demonstrated greatly enhanced ability to trigger allogen-specific T-cell proliferation as compared with IEC-17 cells treated with IFN-gamma alone. The mechanism for the enhanced APC function was investigated by analysing CT-treated IEC-17 cells for increased class II MHC antigen expression or enhanced production of cytokines with known co-stimulatory function. We found no significant increase in class II MHC antigen expression. By contrast, CT strongly promoted, in a dose-dependent fashion, the production of both IL-1 and IL-6 cytokines by IEC-17 cells as compared with untreated epithelial cells. This effect of CT was specific and not due to contaminating endotoxin because excess amounts of soluble toxin receptor, ganglioside GM1, added to the IEC-17 cultures completely abrogated the cytokine response to CT. These results together with our previous findings of enhanced antigen presentation by macrophages stimulated by CT suggest that the potent adjuvant function of CT for induction of mucosal immune responses might be attributed to an enhanced co-stimulating ability of several putative APC in the mucosal immune system: macrophages, B cells and epithelial cells.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Nilsson, A., et al.
(författare)
-
An FTIR study of the hydration and molecular ordering at phase transitions in the monooleoylglycerol/water system
- 1994
-
Ingår i: Chemistry and Physics of Lipids. - : Elsevier BV. - 0009-3084 .- 1873-2941. ; 71:2, s. 119-131
-
Tidskriftsartikel (refereegranskat)abstract
- The liquid-crystalline phases of monooleoylglycerol and water have been investigated by FTIR spectroscopy. The use of polarized IR radiation made it possible to obtain the order parameters of transition moments in the lipid molecule. The order parameters as a function of the temperature and water content have been studied for the lamellar liquid-crystalline phase (L(α)). The decrease in the ordering of the C=O and C-O-CO stretching vibrations in the polar headgroup started earlier than for the CH=CH and CH2 stretching vibrations in the acyl chain region at the phase transition between lamellar and non-lamellar structures. The hydration of the ester carbonyl group increased with the water content. The ordering of the acyl chain decreases drastically in the two-phase regions, while it is nearly constant in the L(α) phase.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
