0000000000338467
AUTHOR
Udo Brand
Signals involved in the early TH1/TH2 polarization of an immune response depending on the type of antigen.
Abstract Background: The early production of distinct cytokines by epidermal cells (ECs) in response to antigen exposure may govern the development of T H1 -like immune responses, such as contact sensitivity, or T H2 -like immune responses, such as IgE-dependent allergies of the immediate type, depending on the type of antigen. Objective: The aim of this study was to compare the signals induced by protein allergens with those induced by haptens in ECs and subsequently in local draining lymph node cells (LNCs) or splenocytes. Methods: BALB/c mice were primed in vivo with the protein allergens ovalbumin or birch pollen or the haptens 2,4-dinitrofluorobenzene or trinitrochlorbenzene, respectiv…
Comparison of allergen-stimulated dendritic cells from atopic and nonatopic donors dissecting their effect on autologous naive and memory T helper cells of such donors
Abstract Background: Because of their production of IL-12, mature dendritic cells (DC) are potent inducers of T H 1 responses. However, recent reports have demonstrated that DCs can also induce T H 2 differentiation. Objective: In the current study we investigated which immune response is induced by DCs in naive CD45RA + or memory CD45R0 + CD4 + T cells from atopic individuals (patients with grass pollen, birch pollen, or house dust mite allergy) compared with nonatopic control subjects. Methods: Immature DCs, generated from peripheral blood monocytes from atopic and nonatopic donors, were pulsed with the respective allergen and fully matured. Then the mature DCs were cocultured in vitro wi…
Allergen-specific immune deviation from a T H2 to a T H1 response induced by dendritic cells and collagen type I
Background: Atopy and IgE production are associated with enhanced allergen-specific TH2 responses. Therefore a causative treatment may result from the deviation of this T H2dominated immune response toward a TH1 response. Objective: This study was carried out to analyze whether dendritic cells, the most potent antigen-presenting cells that are also known to induce antigen-specific T H1 responses, are suitable for therapy of atopic diseases by shifting the allergen-specific TH2 response toward a TH1 response. Methods: Monocyte-derived dendritic cells were used to present allergens in vitro to autologous CD4 + T cells of allergic persons. Because collagen type I activates dendritic cells and …
Inhibition of human allergic T-cell responses by IL-10–treated dendritic cells: Differences from hydrocortisone-treated dendritic cells
Abstract Background: Dendritic cells (DCs) are able to induce human allergic T H 1 responses as well as T H 2 responses. Objective: In this study, we examined the effect of antiinflammatory agents such as IL-10 and hydrocortisone (HC) on the accessory function of DCs and the resulting T-cell response, especially that of T H 2 cells. Methods: Naive and memory CD4 + T cells from atopic donors were stimulated with autologous allergen-pulsed DCs generated from CD14 + monocytes by culture with GM-CSF/IL-4 and fully matured with IL-1β, TNF-α, and PGE 2 in the presence or absence of IL-10 or HC. Results: IL-10–treated DCs and, to a lesser extent, HC-treated DCs showed a decreased expression of MHC…
Influence of extracellular matrix proteins on the development of cultured human dendritic cells.
The development of dendritic cells (DC) is still only partly understood. Recently established culture systems using CD34+ cells or monocytes as precursor cells for the generation of DC indicate the necessity of pro-inflammatory cytokines for their development. In vivo the contact to other cells or to the proteins of the extracellular matrix might also be essential for their development. In our experiments we used granulocyte-macrophage colony-stimulating factor- and IL-4-treated human monocytes as precursor cells to investigate the interaction of DC at different maturation stages with the matrix proteins fibronectin, collagen type I and collagen type IV. We demonstrate a strong beta1-integr…