Current challenges and opportunities for bacillus Calmette-Guérin replacement vaccine candidates.

Bacillus Calmette-Guérin (BCG) remains the only licensed vaccine against human tuberculosis (TB). BCG is a live-attenuated strain of Mycobacterium bovis, with limitations in efficacy against respiratory TB, the most common form of the disease responsible for transmission. However, continues to be used in the immunization programmes of different countries in the absence of another alternative.

Novel vaccination strategies and approaches against human tuberculosis.

Tuberculosis (TB) remains one of a major health problem worldwide. Tuberculosis vaccine research has made an extraordinary progress over the past few years. However, there is still no replacement for the Bacillus Calmette-Guérin vaccine, the only TB vaccine licensed for human use.

Development of tuberculosis vaccines in clinical trials: Current status.

Tuberculosis (TB) is an important infectious disease worldwide. Currently, Bacillus Calmette-Guérin (BCG) remains the only TB vaccine licensed for human use. This TB vaccine is effective in protecting children against severe military TB but offers variable protective efficacy in adults.

Molecular events by which dendritic cells promote Th2 immune protection in helmith infection.

Helminth parasites are a major cause of global infectious diseases, affecting nearly one quarter of the world's population. The common feature of helminth infections is to skew the immune system towards a T-helper 2 (Th2) response that helps to control disease. Dendritic cells (DCs), which are professional antigen-presenting cells, play a critical role for Th2 skewing against helminth parasites.

Peptidomimetics as a new generation of antimicrobial agents: current progress.

Antibiotic resistance is an increasing public health concern around the world. Rapid increase in the emergence of multidrug-resistant bacteria has been the target of extensive research efforts to develop a novel class of antibiotics. Antimicrobial peptides (AMPs) are small cationic amphiphilic peptides, which play an important role in the defense against bacterial infections through disruption of their membranes.

Isolation of IgG antibodies to Toxocara in ankylosing spondylitis patients with acute anterior uveitis.

Purpose: Since few reports had been published on the prevalence of toxocariasis in ankylosing spondylitis (AS) patients with acute non-granulomatous anterior uveitis (ANGAU), the aim of this work was to determine the presence of antibodies against Toxocara canis in AS patients with ANGAU.

Methods: Thirty-six patients (14 female and 22 male) with AS were enrolled in the study. The history of ANGAU was accepted only if diagnosed by an ophthalmologist.

Recent advances in the field of antimicrobial peptides in inflammatory diseases.

Antimicrobial peptides are cationic molecules, which participate in multiple aspects of the immune response including the control of inflammatory diseases, characteristic that make these molecules attractive as therapeutic tools. These peptides are produced in bacteria, insects, plants and vertebrates, and are classified together due to their capacity to directly inhibit the growth of microorganisms, and to regulate the immune response by inducing the secretion of chemokines and cytokines. Various families of antimicrobial peptides have been identified including the cathelicidins and defensins, the most investigated human antimicrobial peptides.

Immunological mechanisms by which concomitant helminth infections predispose to the development of human tuberculosis.

Helminthic infections afflict over 1.5 billion people worldwide, while Mycobacterium tuberculosis infects one third of the world's population, resulting in 2 million deaths per year. Although tuberculosis and helminthic infections coexist in many parts of the world, and it has been demonstrated that the T-helper 2 and T-regulatory cell responses elicited by helminths can affect the ability of the host to control mycobacterial infection, it is still unclear whether helminth infections in fact affect tuberculosis disease.

Reactive oxygen species-activated p38/ERK 1/2 MAPK signaling pathway in the Mycobacterium bovis bacillus Calmette Guérin (BCG)-induced CCL2 secretion in human monocytic cell line THP-1.

Background And Aims: CCL2 plays an important role in mycobacterial infection by inducing leukocyte recruitment and activation. Here we assess the role of reactive oxygen species (ROS) in the secretion of the CCL2 and the activation of mitogen-activated protein kinases (MAPKs) by human monocytic cells infected with Mycobacterium bovis bacillus Calmette Guérin (BCG).

Methods: CCL2 mRNA and protein expression were measured by reverse transcriptase polymerase chain reaction (RT-PCR), quantitative PCR and ELISA.

The human cathelicidin hCAP18/LL-37: a multifunctional peptide involved in mycobacterial infections.

Antimicrobial peptides are predominantly small cationic polypeptides that are classified together on the basis of these molecules to directly kill or inhibit the growth of microorganisms including mycobacteria, and to activate mechanisms of cellular and adaptive immunity. Various families of antimicrobial peptides have been identified, including the cathelicidins. The cathelicidin family is characterised by a conserved N-terminal cathelin domain and a variable C-terminal antimicrobial domain that can be released from the precursor protein after cleavage by proteinases.

Role of interleukin-12 family cytokines in the cellular response to mycobacterial disease.

Interleukin (IL)-12 is a multifunctional cytokine acting as a key regulator of cell-mediated immune responses through the differentiation of naïve CD4+ T cells into type 1 helper T cells (Th1) producing interferon-gamma. As our knowledge of IL-12 family members is rapidly growing, it will be important to specify their involvement in the regulation of mycobacterial infection. This article is a review of the current knowledge regarding the functions of the IL-12 family cytokines in the immune host defense system against mycobacteria.

Role of reactive oxygen species (ROS) in Mycobacterium bovis bacillus Calmette Guérin-mediated up-regulation of the human cathelicidin LL-37 in A549 cells.

The human cathelicidin LL-37 is one of the major antimicrobial peptides of the non-specific innate immune system in Mycobacterium tuberculosis infection. Its expression has been reported in epithelial cells infected with mycobacteria. However, the underlying molecular mechanisms by which Mycobacterium bovis bacillus Calmette-Guérin (BCG) triggers gene transcription of cathelicidin have not been elucidated.

Mycobacterium bovis Bacillus Calmette-Guérin (BCG)-induced activation of PI3K/Akt and NF-kB signaling pathways regulates expression of CXCL10 in epithelial cells.

CXCL10 production is a critical step in limiting mycobacterial infection. Although induction of this chemokine by mycobacteria in epithelial cells has been reported, it is still unclear how CXCL10 is regulated in Mycobacterium bovis BCG-infected epithelial cells. In this study, we demonstrate that phosphatidylinoditol 3-kinase (PI3K)/Akt and the nuclear factor kB (NF-kB) signaling pathways play an important role in CXCL10 expression at the protein and mRNA level in A549 cells.

Expression and regulation of chemokines in mycobacterial infection.

Chemokines are the key molecules that recruit immune cells by chemotaxis and act in leukocyte activation during mycobacterial diseases. Currently, tuberculosis is a leading infectious disease affecting millions of people worldwide. The purpose of this review is to describe a series of recent scientific evidence concerning to the protective role of some members of the CC- and the CXC chemokine subfamilies for the control of mycobacterial infection.

Regulation of human beta-defensin-2 by Mycobacterium bovis bacillus Calmette-Guérin (BCG): involvement of PKC, JNK, and PI3K in human lung epithelial cell line (A549).

Human beta-defensin (HBD)-2 is an inducible antimicrobial peptide that plays an important role in innate immunity. Induction of this peptide by mycobacteria in epithelial cells has been reported. However, the mechanism(s) by which Mycobacterium bovis bacillus Calmette-Guérin (BCG) triggers gene transcription of HBD-2 remains poorly understood.

Role of antimicrobial peptides in host defense against mycobacterial infections.

Worldwide, tuberculosis remains the most important infectious disease causing morbidity and death. Currently, at least one-third of the world's population is infected with Mycobacterium tuberculosis. In addition, the World Health Organization estimates that about 8-10 million new tuberculosis cases occur annually worldwide and this incidence is currently increasing.

Expression and secretion of cathelicidin LL-37 in human epithelial cells after infection by Mycobacterium bovis Bacillus Calmette-Guérin.

The antimicrobial cathelicidin LL-37 is considered to play an important role in the innate immune response to tuberculosis infection. However, little is known about the induction and secretion of this antimicrobial peptide in A549 epithelial cells after infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG), the world's most widely used tuberculosis vaccine. In this study, we investigated the effect of M.

Mycobacterium bovis Bacillus Calmette-Guérin (BCG) stimulates IL-10 production via the PI3K/Akt and p38 MAPK pathways in human lung epithelial cells.

Infection of human cells with mycobacteria has been shown to result in the production of anti-inflammatory cytokines. However, the signaling pathways that regulate the Mycobacterium bovis BCG-induced interleukin (IL)-10 production are currently unknown. In the present study, we investigated the involvement of phosphatidylinoditol 3-kinase (PI3K)/Akt and the p38 MAPK signaling pathways in the secretion of IL-10 in human lung epithelial cells (A549) after infection with M.

Sphingosine kinase, phosphatidylinositol 3-kinase, Akt, NF-kappaB, and p300 are required for CCL5 production in Mycobacterium bovis Bacillus Calmette-Guérin (BCG)-infected epithelial cells.

CCL5 is a key in limiting mycobacterial infection. Although NF-kappaB has been implicated, signaling cascades involved in CCL5 production by epithelial cells following infection with Mycobacterium bovis BCG are still not defined. Here we show that using pharmacological inhibition of sphingosine kinase (SPK), striking inhibition of M.

Mycobacterium bovis BCG Toll-like receptors 2 and 4 cooperation increases the innate epithelial immune response.

Background: Although CXCL8 is known to be important both in enhancing local antimycobacterial activity and in driving recruitment of leukocyte subsets during inflammatory processes, little information is known about the relationship between transcriptional upregulation of the Mycobacterium bovis BCG-induced CXCL8 secretion and TLR signaling.

Methods: Phosphorylation of ERK1/2 was analyzed by immunoblot analysis. The levels of immunoreactive CXCL8 were measured with cytokine-specific commercial ELISA kits.

Mycobacterium bovis bacillus Calmette-Guerin induces CCL5 secretion via the Toll-like receptor 2-NF-kappaB and -Jun N-terminal kinase signaling pathways.

In response to Mycobacterium bovis bacillus Calmette-Guérin (BCG), CC chemokines are secreted from host cells to attract components of the innate and adaptive immune systems to the site of infection. Toll-like receptor 2 (TLR2) has been shown to recognize M. bovis BCG and to initiate signaling pathways that result in enhanced secretion of CC chemokines.