Health Boards
Tue-31-01-2012, 15:18 PM
Background:
Patients with psoriasis who had raised IgG and/or IgA antigliadin antibodies showed clinical improvement in a trial with a gluten-free diet. The selection of patients for the diet treatment was based on the presence of specific antibodies, i.e. the result of humoral immunity.
Objectives:
As psoriasis is now considered to be a T cell-mediated disease we decided to challenge peripheral blood mononuclear cells (PBMCs) in vitro from randomly selected patients with well-defined wheat proteins/peptides to explore the possibility of identifying a specific antigen with T cell activating properties in a subgroup of patients.
Methods:
PBMCs from 37 patients (20 female and 17 male; mean age 49 years) and 37 healthy controls (12 female and 25 male; mean age 57 years) were included. Not all patients participated in all experiments. The PBMCs were exposed in vitro with the following wheat proteins/peptides in various concentrations: total albumins, 0·28 α-amylase inhibitor and the synthetic peptides, p31–43, p57–68 and p62–75, based on coeliac-active sequences of α-gliadin. The proliferative response was measured as counts per minute after the cells had been pulsed with methyl-3H-thymidine.
Result: Albumin, α-amylase inhibitor, p31–43 and p57–68 elicited a significant response in both patients and controls but showed no differences between the groups. The response induced by the α-amylase inhibitor was higher than that induced by the albumin fraction and the p31–43 and p57–68 peptides. At a concentration of 25 μg mL−1, five of 36 patients with psoriasis responded positively to the p62–75 peptide and none of the 33 controls, using a stimulation index of 2·4 as the cut-off level (P < 0·05). These five patients did not show clinical features that differed from the remaining patients. Among the responding patients the relative number of CD4+ cells increased in some but not all after in vitro challenge with the albumins, 0·28 α-amylase inhibitor, and p62–75. These antigens could also induce in vitro the expression of the homing antigen cutaneous lymphocyte antigen (CLA) in a few patients and controls.
Conclusions: The wheat protein antigens, especially the p62–75 peptide, might be of interest in a subgroup of patients with psoriasis.
Source: British Journal of Dermatology onlinelibrary.wiley.com
Patients with psoriasis who had raised IgG and/or IgA antigliadin antibodies showed clinical improvement in a trial with a gluten-free diet. The selection of patients for the diet treatment was based on the presence of specific antibodies, i.e. the result of humoral immunity.
Objectives:
As psoriasis is now considered to be a T cell-mediated disease we decided to challenge peripheral blood mononuclear cells (PBMCs) in vitro from randomly selected patients with well-defined wheat proteins/peptides to explore the possibility of identifying a specific antigen with T cell activating properties in a subgroup of patients.
Methods:
PBMCs from 37 patients (20 female and 17 male; mean age 49 years) and 37 healthy controls (12 female and 25 male; mean age 57 years) were included. Not all patients participated in all experiments. The PBMCs were exposed in vitro with the following wheat proteins/peptides in various concentrations: total albumins, 0·28 α-amylase inhibitor and the synthetic peptides, p31–43, p57–68 and p62–75, based on coeliac-active sequences of α-gliadin. The proliferative response was measured as counts per minute after the cells had been pulsed with methyl-3H-thymidine.
Result: Albumin, α-amylase inhibitor, p31–43 and p57–68 elicited a significant response in both patients and controls but showed no differences between the groups. The response induced by the α-amylase inhibitor was higher than that induced by the albumin fraction and the p31–43 and p57–68 peptides. At a concentration of 25 μg mL−1, five of 36 patients with psoriasis responded positively to the p62–75 peptide and none of the 33 controls, using a stimulation index of 2·4 as the cut-off level (P < 0·05). These five patients did not show clinical features that differed from the remaining patients. Among the responding patients the relative number of CD4+ cells increased in some but not all after in vitro challenge with the albumins, 0·28 α-amylase inhibitor, and p62–75. These antigens could also induce in vitro the expression of the homing antigen cutaneous lymphocyte antigen (CLA) in a few patients and controls.
Conclusions: The wheat protein antigens, especially the p62–75 peptide, might be of interest in a subgroup of patients with psoriasis.
Source: British Journal of Dermatology onlinelibrary.wiley.com