Current Pharmaceutical Design - Volume 22, Issue 41, 2016

The triggering receptor expressed on myeloid cells (TREM)-1 is a member of the Ig-like immunoregulatory receptor family and a major amplifier of innate immune responses. TREM- 1 has been implicated in the development and perpetuation of a number of inflammatory disorders, and soluble TREM-1 levels are a clinically valuable diagnostic and prognostic biomarker in patients with sepsis and other types of acute and chronic inflammation- associated diseases, easily detectable in biological fluids. High TREM-1 expression in macrophages infiltrating human tumors and increased concentrations of soluble TREM-1 also correlate with aggressive tumor behavior and recurrence and are a relevant independent predictor of poor patient survival. Pharmacological inhibition of TREM-1 has proven effective in preclinical mouse models of infectious and non-infectious inflammatory disorders and malignancies, conferring survival advantages and protecting from organ damage or tumor growth by attenuating inflammatory responses. This review aims at providing a comprehensive overview of the state of the art on TREM-1 research. We review the literature addressing TREM-1 role in the amplification of myeloid cell inflammatory responses at pathologic sites and its relevance in the development, severity, and progression of inflammatory diseases and cancer. Furthermore, we discuss recent advances in the pharmacological use of TREM-1 inhibitors in mouse preclinical models, emphasizing their potential in new strategies for the treatment of acute and chronic inflammatory conditions and for therapeutic intervention in cancer. This information will be of value to investigators in the field of pharmacology, drawing attention to novel therapeutic opportunities to complement current treatment approaches.

For more than a century, scientists have tried to exploit the anti-tumoral potential of the immune system to treat cancer. However, clinical success was traditionally limited. Consequently, classical anti-neoplastic treatments such as surgery, radiotherapy, and chemotherapy used to be the first line of treatment. Fortunately, this scenario is changing, particularly with the identification of immune checkpoint inhibitors. Now more than ever, it becomes essential to understand how cancer cells modulate the immune system. In this review, we summarize main mechanisms of antigen presentation in the tumor microenvironment, a main event in the establishment of anti-tumor immunity. Specifically, we focus on recent progress in mechanisms involved in tumor antigen presentation, as well as on strategies cancer cells develop to favor immune suppressive and immune tolerant enironments. In addition, we briefly discuss current therapeutic approaches to overcome tumor immune evasion.

Virulence capsular polysaccharide (Vi antigen) and Salmonella`s Pathogenicity Island type 1 and 2 TTSS (SPI-1 and SPI-2 TTSS) are important membrane virulence factors of human restricted pathogen S. Typhi. The Vi antigen modulates different proinflammatory signaling pathways in infected macrophages, microfold epithelial and dendritic cells. SPI-2 TTSS and its effectors are required for promoting bacterial intracellular survival, replication and apoptosis while SPI-1 and its effectors are associated with invasion of microfold epithelial cells. The purified Vi-antigen has been used as a vaccine against disease. It is a T cell independent antigen that induces moderate efficacy ( 55%) in adults and no efficacy in children bellow two years of age. Carrier protein conjugation of the Vi antigen has been successfully used to confer T cell dependency and to develop Vi conjugate vaccines with high efficacy, around 89% in three years, in all age groups. So far, the attenuated live vaccine with constitutive expression of Vi antigen and the SPI-2 TTSS mutant vaccine, progressed to phase 3 clinical tests. Particularly, the live attenuated vaccine with constitutive expression of Vi antigen might be also used to optimize the efficacies of other vaccines. The current preclinical studies consider also development of novel T cell independent vaccines from recombinant proteins and generalized modules for membrane antigens. An approach for future antivirulence therapy against disease might also consider the bioactive compounds with ability to inhibit TTSS secretions. It is concluded that combined approaches my successfully reduce S. Typhi infection in this new globalized era.

Asthma is an allergic disease that affects approximately 300 million people worldwide. Two of its phenotypes routinely assessed at the clinic include airway hyperresponsiveness and IgE production. They can be measured in a non-invasive manner and have been used for genetic studies. The genetic complexity of asthma and its phenotypes makes it difficult to map their genetic contributors. Human studies require large sample sizes and proper segregation of the population to control for potential confounding factors. As an alternative, asthma genetics can be studied in mice due to the high degree of homology in the genome and immune response between mice and humans. The variety of mouse strains and allergic asthma protocols allow to study different aspects of the disease while controlling for the genetic background. Studying the genetic basis of asthma phenotypes has helped gain a better understanding of the disease mechanism. Candidate genes identified from genetic studies have served as targets for the development of new and specialized treatments. New treatments are high in demand as the symptoms of a large number of asthmatics are not properly controlled with the existing treatment guidelines involving corticosteroids, β2-adrenoreceptor agonists, and anti-leukotrienes or leukotriene modifiers. Promising findings have been obtained from studies exploring new treatments targeting specific immune cell mediators, which were identified as candidates in genetic studies, and cell adhesion molecules. In addition to targeting members of the Th1/Th2 inflammatory profile, mediators of the omega-3 fatty acid pathway are also emerging as novel targets of drug intervention for allergic asthma.

Background: Although some patients with obstructive lung disease (OLD) have features of both asthma and chronic obstructive pulmonary disease (COPD), the term "asthma-COPD overlap syndrome (ACOS)" was coined only relatively recently. However, there are gaps in our knowledge of the clinical features, pathogenesis, prognosis, and management of ACOS patients. Objectives: To review the literature on ACOS to determine the extent to which the clinical features, pathologic mechanisms, clinical outcomes, and current therapeutic approaches for ACOS differ from those in patients with asthma alone or COPD alone. Methods: PUBMED searches were conducted to review the demographic and clinical features, comorbidities, lung imaging characteristics, prognoses, pathologic mechanisms, and current therapeutic approaches for patients with ACOS versus asthma alone or COPD alone. Results: Criteria that are used to diagnose ACOS vary considerably. Overall, ACOS patients have higher symptom burdens (especially dyspnea), poorer quality of life scores, and more frequent and severe exacerbations than patients with COPD alone or asthma alone. However, there are conflicting reports on the prognosis of ACOS patients. Imaging studies indicate that ACOS is predominantly an airway disease. ACOS has been linked to the presence of Th2-type immune responses in COPD airways and Th1-type immune responses in asthmatic airways. Current therapeutic options for ACOS patients include inhaled corticosteroids and bronchodilators. However, randomized clinical trials have not yet been conducted to optimize the management of ACOS patients. Conclusion: ACOS patients have clinical features that are now well defined, but additional studies are needed to provide novel insights into ACOS pathogenesis, and to optimize the treatment of these patients.

A main focus in healthcare is the active search for alternative strategies to antibiotics, both for prophylactic and therapeutical interventions, due to the accelerated and widespread increase in antibiotic resistance. This problem is more marked for patients with recurrent infections, in which the risk for antibiotic resistance and adverse effects is higher and can be life-threatening. Although antibiotics remain the mainstay of treatment for infectious diseases, prophylactic vaccines via the mucosal route in defined populations of patients with recurrent infections has gained use in recent years. Concomitantly, relevant advances in the formulation and administration of these vaccines driven by an increased knowledge of mucosal immunity have expanded their use, although still in its infancy. These drugs target both the innate and adaptive immune systems, at the actual point of entry of most pathogens. A fascinating new application of the concepts of trained immunity may open novel studies in their potential uses, given the paradoxically simultaneous pro-tolerogenic and boosting effector effects on diverse immune cells for different antigens. Here we delineate an updated review on the immunomodulatory mechanisms of mucosal polybacterial vaccines.

The need for the improvement of vaccine potency as well as reducing toxicity in healthy recipients has motivated studies of the formulation of vaccines regarding control of how, when, and where antigens and adjuvants encounter immune cells and other cells/tissues following vaccine administration. Immunostimulatory complexes (ISCOMs) and ISCOMATRIXTM adjuvants are versatile and flexible systems with various phospholipids and saponin components. They are being used in novel vaccines for either infectious diseases or cancer. This article presents a brief review of the latest developments using such adjuvants and possible new applications.

Cumulative recent evidence from clinical trials, observational studies and case reports has shown that subcutaneous administration of immunoglobulin (SCIg) exerts similar immunomodulatory capacity than intravenous immunoglobulin (IVIg) in autoimmune neurological diseases. Besides the beneficial clinical effects, the profile of safety and autonomy for the patient is higher for SCIg, while it is cost-saving in terms of the health resources used. However, there are still very few approved indications for SCIg and a certain resistance to choose SCIg for other autoimmune conditions even despite patients’ interests. Here we present an updated review of the known immunomodulatory mechanisms of action of Ig and the current hypothesis supporting the clinical and immunological advantages of SCIg over IVIg that derive from their specific pharmacokinetic features.

There have been few changes over the last 50 years in the treatment of Systemic lupus erythematosus (SLE), using non-specific anti-inflammatory agents such as: nonsteroidal anti-inflammatory drugs along with the immune cell modulating agent hydroxychloroquine for mild disease, and broad spectrum immunosuppressants plus antiinflammatories such as corticosteroids, azathioprine, cyclophosphamide, or mycophenolate during flares or severe disease with organ involvement. In some patients, the response is inadequate and side effects appear from mild unpleasant up to severe toxicity. Drug metabolism and clearance may be severely compromised. Therefore, it is a priority to develop better treatments with fewer adverse events that can be used at different stages of disease activity. In recent years, a member of the tumor necrosis factor (TNF) family, soluble human B Lymphocyte Stimulator protein (BLyS), also referred to as B-cell activating factor (BAFF) and TNFSF13B has been studied extensively. This protein is synthesized by myeloid cell lines, specifically interacts with B lymphocytes and increases their life-span. BlyS plays a key role in the selection, maturation and survival of B cells and it has a significant role in the pathogenesis of SLE. In this review, we analyzed the role of BLyS as a diagnostic/prognostic marker and/or therapeutic target for lupus patients, and the different clinical studies published using belimumab.

The purpose of each dosage form is to provide an optimal therapeutic effect with a minimum dose and with minimal side effects. This is particularly relevant for drugs that require systemic administration, higher dosing and/or show lower bioavailability. Тhe eye as an anatomical structure is an extremely protected organ. In this regard, providing an optimal bioavailability in the eye tissues, resulting in the desired therapeutic effect represents a major challenge. This is especially true for the treatment of diseases, affecting the posterior segment after topically administered drug formulations. The use of nano- and microcarriers of drug substances may be an appropriate technological approach, to provide a high bioavailability of the drug substance for a certain interval of time at the right place. The purpose of this review is to indicate how nano- and microcarriers of drug substances can solve the problems with the drug delivery in the ocular tissues, to indicate the possible hazards and side effects, depending on the polymer nature and route of administration, and to visualize the future potential of these carriers in the pharmaceutical practice.

Peroxisome proliferator-activated receptor γ (PPARγ) has been considered as the master regulator for adipogenesis of bone marrow stromal cells (BMSCs). However, there are few reports regarding the effect of PPARγ gene silencing on osteogenic and adipogenic differentiation in rat BMSCs, and no reports about tissue targeting and conditional knockdown of PPARγ gene. In this study, we construct rat PPARγ gene shRNA Tet-on lentiviral vector, the lentiviral vector facilitated tetracycline (which has the characteristics of bone targeting)-inducible knockdown specific to PPARγ gene, and transfect it into BMSCs, the silencing effects induced by tetracycline is significant. The expression of the adipogenic factors adipocyte determination and differentiation-dependent factor 1 (ADD1) and recombinant CCAAT/enhancer binding protein alpha (C/EBPα) were decreased as measured by RT-PCR and Western blot assay following PPARγ silencing. In contrast, expression of the osteogenic genes encoding collagen I and Cbfa1/Runx2 were increased. In adipogenic medium, PPARγ-shRNA transfection reduced the lipid droplet count as measured by Oil red O staining when compared to the control groups. In osteogenic medium, PPARγ-shRNA increased the activity of alkaline phosphatase and the amount of calcium deposition as measured by Alizarin red S staining. These results suggest that the rat PPARγ gene shRNA Teton lentiviral vector decreases adipogenic differentiation and promotes osteogenic differentiation in BMSCs induced by tetracycline.