Antigen presenting cells (APCs), especially dendritic cells (DCs), play a major role in the hierarchy of the induction of immune reactions. DCs are widely accepted as the most potent APCs capable of inducing protective adaptive immune responses in addition to tolerance to self-antigens. The role of DCs is currently being investigated in the context of many disease and therapeutic settings. In response to a variety of microbial and endogenous stimuli, resting DCs in peripheral tissues undergo a complex maturation process that might involve the regulation of genes that control distinct DC functions. The different functional properties of DCs are also linked to the existence of several subpopulations in humans and animals that differ in response to stimuli.

On the other hand, immune reactions can be controlled by the so-called regulatory T cells that can interact with APCs such as DCs. The most commonly known and explored regulatory T cells, namely, Tregs, are CD4⁺CD25^highFoxP3^highCD127^low in humans. They have been studied in different autoimmune diseases but also in the transplant setting. The invariant NKT (iNKT) lymphocytes represent another immunoregulatory T-cell population whose functions are being progressively deciphered.

In all, DCs and regulatory lymphocytes are currently being considered as attractive targets towards manipulation of the immune system for therapeutic purposes. With this background, this special issue will be focussed on topics addressing the role, functions, and pathophysiology of DCs and regulatory cells and their interactions with other immune effectors. We are interested in papers that explore aspects of DC and regulatory cells immunobiology in humans and also in animal models. Potential topics include, but are not limited to:

• Development and testing of novel and effective immunotherapeutic tools based on DCs and/or regulatory cells
• Development of pharmacologic strategies to manipulate DCs and/or regulatory cells
• Elucidating the role of DCs and/or regulatory cells in different physiological and pathological conditions
• Identifying biomarkers/correlates of immunity in response to DC and/or regulatory cells vaccines
• New cellular and animal models to test and understand the role of DCs and/or regulatory cells
• The influence of immunomodulatory and immunosuppressive drugs on DC and/or regulatory cells properties

Before submission authors should carefully read over the journal's Author Guidelines, which are located at http://www.hindawi.com/journals/jir/guidelines/. Prospective authors should submit an electronic copy of their complete manuscript through the journal Manuscript Tracking System at http://mts.hindawi.com/submit/journals/jir/drc/ according to the following timetable: