Cor a 1-reactive T cells and IgE are predominantly cross-reactive to Bet v 1 in patients with birch pollen-associated food allergy to hazelnut.

Background: IgE- and T-cell cross-reactivity contribute to the birch pollen-food syndrome.

Objectives: We performed a comprehensive analysis of T-cell cross-reactivity in primary cell cultures, facilitating the identification of allergen-specific T-cell subpopulations from individual patients.

Methods: Patients with birch pollen allergy and associated food allergy to hazelnuts, carrots, or both were analyzed for IgE cross-reactivity, T-cell responses, and T-cell cross-reactivity to recombinant Bet v 1.

Neuronal nitric oxide synthase modulates maturation of human dendritic cells.

Dendritic cells (DCs) are the most potent APCs of the immune system. Understanding the intercellular and intracellular signaling processes that lead to DC maturation is critical for determining how these cells initiate T cell-mediated immune processes. NO synthesized by the inducible NO synthase (iNOS) is important for the function of murine DCs.

MAP kinase p38 and its relation to T cell anergy and suppressor function of regulatory T cells.

Diverse regulatory T cell populations (Treg) are important for the control of self tolerance and immune homeostasis. These include naturally occurring CD4+CD25+ Treg (nTreg) and induced Treg (iTreg). Tolerogenic dendritic cells, modulated by IL-10, are able to convert peripheral T cells into iTreg.

Tolerogenic dendritic cells in health and disease: friend and foe!

Dendritic cells (DC) are professional antigen presenting cells and crucial mediators of immune defence and tolerance. Experimental evidence in vitro and in vivo has shown that tolerogenic DCs (tDCs) contribute to prevention of autoimmunity and allergic reactions but might also worsen the course of cancer and certain infectious diseases. The development of in vitro protocols for the generation of human tDCs has greatly improved the knowledge of basic principles for tolerance induction by tDCs and fosters approaches for the therapeutic manipulation of tDCs in conditions such as severe autoimmunity, allergy or transplantation.

Activation of MAP kinase p38 is critical for the cell-cycle-controlled suppressor function of regulatory T cells.

Regulatory T cells play an essential role in the control of self-tolerance and processes of adaptive immunity. Tolerogenic IL-10-modulated human dendritic cells (IL-10DCs) induce anergic T cells with strong suppressive properties (iTregs) that inhibit the activation of effector T cells. In this study, we evaluated the interaction between cell-cycle regulation and intracellular signaling in these iTregs.

Simian immunodeficiency viruses with defective nef genes show increased susceptibility to the noncytotoxic antiviral activity of CD8+ lymphocytes.

The noncytotoxic soluble factor produced by CD8+ T cells inhibits replication of HIV and SIV in vitro and is thought to play a crucial role in combatting infection in vivo. We determined the effect of human CD8+ lymphocytes on the in vitro replication potential of both wild-type and nef-defective mutants of the simian immunodeficiency virus SIVmac251. Although replication of wild-type SIVmac251 in unstimulated human PBMC supplemented with IL-2 was unaffected by the presence of CD8+ T cells, the nef mutants were susceptible to the inhibitory effects.