Search

Hepatitis C virus (HCV) is a blood-borne pathogen which has chronically infected people worldwide. Therefore, it is of utmost importance to design prophylactic and therapeutic vaccine in order to control HCV infection. To date, several researchers have attempted to improve the efficiency of HCV vaccine by using different adjuvants. However, a few studies have focused on the synthetic immunomodulatory drugs as adjuvants for HCV vaccine. Recently, researchers have shown that lenalidomide, which is used to treat the patients with multiple myeloma, is capable of improving the immune system factors. In this paper, two doses of lenalidomide along with pcDNA3.1 + NS3 as HCV DNA vaccine were administrated in mice models and the percentage of regulatory T cells (Treg cells) and the cells with PD-1 + expression in spleen of mice model were investigated by flow cytometry method. Additionally, activities of CTL cells and NK cells were evaluated in spleen of prophylactic and therapeutic mice models via LDH method. Results of the Treg and PD-1 analysis showed that low dose of lenalidomide along with pcDNA3.1 + NS3 can noticeably decrease the percentage of Treg cells and the cells with PD-1 + expression, while lenalidomide can significantly increase the CTL and NK activity in mice models. Also, results of the therapeutic mice model, in which SP2/0 cells- challenged mice were treated with 5 mg/kg lenalidomide in combination with pcDNA3.1 + NS3, reasonably agreed with those of the prophylactic model. Finally, it was found that lenalidomide can reduce the level of Treg cells which results in lower the cells with PD-1 + expression and subsequently higher CTL and NK cell activities. This study concluded that lenalidomide possess the characteristics of an ideal adjuvant candidate for use in combination with HCV DNA vaccine in order to promote the immune response and vaccine efficiency. [ABSTRACT FROM AUTHOR]

Abstract: The generation of both antibody and CD8+ T cell responses against pathogens is considered important for many advanced vaccines for diseases including tuberculosis, HIV and malaria. However, most current vaccines are delivered into muscle by the needle and syringe method and induce protection via humoral (antibody) immune responses. In this paper, we test the hypothesis that delivering a model subunit protein antigen (ovalbumin) to the skin''s abundant immune cell population using a densely packed microprojection array (Nanopatch) enhances CD8+ T cell responses. We found that the Nanopatch significantly enhanced the CD8+ T cell responses when compared to intramuscular delivery of both antigen-only and adjuvanted cases (Quil-A and CpG; separately). To our knowledge, this is the first published study demonstrating significantly improved CD8+ T cell responses achieved by delivering subunit vaccines to the skin''s abundant immune cell population. Successfully replicating these findings in humans could significantly advance the reach of vaccines. [Copyright &y& Elsevier]

Most mammalian immune systems and parasites have co-evolved over the millennia, interacting within a common environment and communicating through a common language. This language is comprised of copious dialects in which a variety of host innate and acquired immune pathways actively interact with a multitude of parasite-specific survival strategies. Nonetheless, a simplified language is likely present since the same basic molecular and cellular mechanisms are associated with resistance or susceptibility to parasite infection. Protective immunity against protozoa within the phylum Apicomplexa (e.g. Cryptosporidia, Eimeria, Neospora, Plasmodia and Toxoplasma) is generally CD4+ T cell-dependent and elicited along the IL-12/IFN-γ/iNOS effector axis. This simplified language can be decoded in part by significant advances in understanding naı¨ve T cell activation, differentiation and generation of immunologic memory. Vaccine adjuvants and new immunisation strategies for generation of more potent immunity can also be viewed through this common language lens. The aim of this paper is to summarise recently published fundamental immunology studies, their relevance through examples in specific coccidian-host immune dialects, and how this simplified language can be used for the more rationale design of parasite vaccine control strategies. [Copyright &y& Elsevier]

Dendritic cells (DCs) are recognized as the sole professional antigen-presenting cells capable of priming naive T cells of the helper and cytotoxic phenotypes. This property is presently exploited with success in vaccinal strategies against pathogens or tumor cells that otherwise escape immune recognition, but the repeated infusions of ex vivo expanded and sensitized DCs are usually required to achieve protection. In this paper, we demonstrate that liposomal antigens can efficiently relay and propagate the action of DCs, inducing a strong long-term response against their associated antigen. Their effect is mainly achieved by improving the ex vivo loading of DCs and by efficiently channeling the activation stimulus into the induction of effector function. This is demonstrated by the sustained immunoglobulin production as well as by the sustained lymphoproliferation and the increased cytokine secretion that can be achieved upon restimulation of DC-primed immune cells with limited amount of liposomal antigenic material. Being well-tolerated and easily prepared, liposomal antigens could therefore be expected to significantly contribute to the efficiency and to a more general utilization of the highly promising but rather cumbersome DC-based immunotherapies. [ABSTRACT FROM AUTHOR]