RESUMEN
PURPOSE: The mast cell plays a pivotal role in the human immune response. Crosslinking of 2 IgE molecules bound to the high affinity IgE receptor (FcepsilonRI) on the surface of the mast cell results in mast cell degranulation and the release of several proinflammatory mediators. Patients with type-I allergy have increased levels of IgE in the blood compared to healthy individuals. METHODS: In a 6-week culture system of stem cells to human mast cells we investigated the effect of the concentration of IgE. The mast cells were cultured with different concentrations of IgE for the last 10 days of the maturation period. It was observed how the IgE concentration affects the histamine release, FcepsilonRI density on the mast cell surface and the concentration of other mediators. RESULTS: A clear correlation between IgE concentration in culture medium and the release of histamine upon activation was observed. It showed a bell-shaped dose response curve, with maximal response around an IgE-concentration of 250 ng/mL. Furthermore, the sensitivity of the mast cells and surface density of FcepsilonRI on mast cell surface was also influenced by the IgE concentration in the culture medium. CONCLUSIONS: IgE in the culture medium during the last 10 days of mast cell maturation influences the release of the preformed mediator histamine after mast cell activation and the density of FcepsilonRI on the mast cell surface. The release of the de novo synthetized mediator prostaglandin D2 and the expression of chymase and tryptase are not influenced by IgE in culture medium.
Asunto(s)
Humanos , Quimasas , Histamina , Liberación de Histamina , Hipótesis de la Higiene , Hipersensibilidad , Inmunoglobulina E , Mastocitos , Prostaglandina D2 , Células Madre , TriptasasRESUMEN
PURPOSE: The mast cell plays a pivotal role in the human immune response. Crosslinking of 2 IgE molecules bound to the high affinity IgE receptor (FcepsilonRI) on the surface of the mast cell results in mast cell degranulation and the release of several proinflammatory mediators. Patients with type-I allergy have increased levels of IgE in the blood compared to healthy individuals. METHODS: In a 6-week culture system of stem cells to human mast cells we investigated the effect of the concentration of IgE. The mast cells were cultured with different concentrations of IgE for the last 10 days of the maturation period. It was observed how the IgE concentration affects the histamine release, FcepsilonRI density on the mast cell surface and the concentration of other mediators. RESULTS: A clear correlation between IgE concentration in culture medium and the release of histamine upon activation was observed. It showed a bell-shaped dose response curve, with maximal response around an IgE-concentration of 250 ng/mL. Furthermore, the sensitivity of the mast cells and surface density of FcepsilonRI on mast cell surface was also influenced by the IgE concentration in the culture medium. CONCLUSIONS: IgE in the culture medium during the last 10 days of mast cell maturation influences the release of the preformed mediator histamine after mast cell activation and the density of FcepsilonRI on the mast cell surface. The release of the de novo synthetized mediator prostaglandin D2 and the expression of chymase and tryptase are not influenced by IgE in culture medium.
Asunto(s)
Humanos , Quimasas , Histamina , Liberación de Histamina , Hipótesis de la Higiene , Hipersensibilidad , Inmunoglobulina E , Mastocitos , Prostaglandina D2 , Células Madre , TriptasasRESUMEN
BACKGROUND: A small subgroup of atopic dermatitis (AD) patients show low total and allergen-specific immunoglobulin (IgE) levels. This subgroup has been termed 'intrinsic' AD (IAD) as compared to its counterpart 'extrinsic' AD (EAD). However, the difference of cytokine expression between IAD and EAD has not been fully understood. OBJECTIVE: To compare the expression of various inflammatory cytokines in the peripheral blood mononuclear cells (PBMCs) and lesional skin of patients with IAD and EAD, which are known to be associated with AD pathophysiology. METHODS: We assessed the protein levels of cytokines in the PBMCs and lesional skin. We evaluated the levels of IL-3, IL-4, IL-5, IL-6, IL-10, IL-13, FcepsilonRI and FcepsilonRII from the PBMCs and lesional skin of patients with IAD and EAD. RESULTS: The patients with EAD had elevated levels of the IL-3 expression in their PBMCs and elevated levels of FcepsilonRI in their lesional skin compared to that of the patients with IAD. The expression of other cytokines did not differ in the PBMCs and lesional skin from the two subgroups. CONCLUSION: This study suggests that IL-3 could be associated with the pathophysiology of EAD as compared to that of IAD, along with FcepsilonRI which was previously shown to be highly expressed in EAD patients.