Effects of lipopolysaccharide-loaded PLGA nanoparticles in mice model of asthma by sublingual immunotherapy

Implications of IL-21 in solid tumor therapy

Cancer, the most deadly disease, is known as a recent dilemma worldwide. Presently different treatments are used for curing cancers, especially solid cancers. Because of the immune-enhancing functions of cytokine, IL-21 as a cytokine may have new possibilities to manipulate the immune system in disease conditions, as it stimulates NK and CTL functions and drives IgG antibody production. Indeed, IL-21 has been revealed to elicit antitumor-immune responses in several tumor models. Combining IL-21 with other agents, which target tumor cells, immune-regulatory circuits, or other immune-enhancing molecules enhances this activity. The exciting breakthrough in the results obtained in pre-clinical situations has led to the early outset of present developing clinical trials in cancer patients. In the paper, we have reviewed the function of IL-21 in solid tumor immunotherapy.

The role of indoleamine 2,3-dioxygenase in allergic disorders

The amino acid tryptophan (TRP) is critical for the expansion and survival of cells. During the past few years, the manipulation of tryptophan metabolism via indoleamine 2,3 dioxygenase (IDO) has been presented as a significant regulatory mechanism for tolerance stimulation and the regulation of immune responses. Currently, a considerable number of studies suggest that the role of IDO in T helper 2 (Th2) cell regulation may be different from that of T helper 1 (Th1) immune responses. IDO acts as an immunosuppressive tolerogenic enzyme to decrease allergic responses through the stimulation of the Kynurenine-IDO pathway, the subsequent reduction of TRP, and the promotion of Kynurenine products. Kynurenine products motivate T-cell apoptosis and anergy, the propagation of Treg and Th17 cells, and the aberration of the Th1/Th2 response. We suggest that the IDO-kynurenine pathway can function as a negative reaction round for Th1 cells; however, it may play a different role in upregulating principal Th2 immune responses. In this review, we intend to integrate novel results on this pathway in correlation with allergic diseases.

Nanoparticle-based immunotherapy: state of the art and future perspectives

INTRODUCTION

For several years now, medicine has been benefiting from the contribution of nanoparticles (NPs) technology for both diagnosis and therapy. They can be used as adjuvants, being capable per se of immune-modulating activity, or as carriers for molecules to be transported to a specific target, eventually loaded with specific ligands favoring specific uptake.

AREAS COVERED

The review focuses on experimental use of NPs as adjuvants/carriers for allergen immunotherapy (AIT). Human clinical trials conducted so far are discussed.

EXPERT OPINION

Results of experimental studies and recent clinical trials support the use of NPs as carrier/adjuvant in AIT. Comparisons between NP-based and classical AIT are needed, to show the usefulness of the NP-based approach. However, there are still unsolved problems: the persistence of non-degradable NPs with possible toxicological consequences, and the formation of the protein corona around the NPs, which could alter their activity and fate. Virus-like particles seem the most promising NPs for allergy treatment, as for other vaccines. Over the next decade, NP-based AIT will be largely used to treat allergic disorders.