TREM2 is a receptor for non-glycosylated mycolic acids of mycobacteria that limits anti-mycobacterial macrophage activation.

Mycobacterial cell-wall glycolipids elicit an anti-mycobacterial immune response via FcRγ-associated C-type lectin receptors, including Mincle, and caspase-recruitment domain family member 9 (CARD9). Additionally, mycobacteria harbor immuno-evasive cell-wall lipids associated with virulence and latency; however, a mechanism of action is unclear. Here, we show that the DAP12-associated triggering receptor expressed on myeloid cells 2 (TREM2) recognizes mycobacterial cell-wall mycolic acid (MA)-containing lipids and suggest a mechanism by which mycobacteria control host immunity via TREM2.

The liposome of trehalose dimycolate extracted from M. bovis BCG induces antitumor immunity via the activation of dendritic cells and CD8 T cells.

Intravesical Bovis bacillus Calmette-Guérin (BCG) therapy is the most effective immunotherapy for bladder cancer, but it sometime causes serious side effects because of its inclusion of live bacteria. It is necessary to develop a more active but less toxic immunotherapeutic agent. Trehalose 6,6'-dimycolate (TDM), the most abundant hydrophobic glycolipid of the BCG cell wall, has been reported to show various immunostimulatory activities such as granulomagenesis and adjuvant activity.

The rough colony morphotype of exhibits high virulence in human macrophages and mice.

The incidence of complex (MAC) pulmonary disease (MAC PD), a refractory chronic respiratory tract infection, is increasing worldwide. MAC has three predominant colony morphotypes: smooth opaque (SmO), smooth transparent (SmT) and rough (Rg). To determine whether colony morphotypes can predict the prognosis of MAC PD, we evaluated the virulence of SmO, SmT and Rg in mice and in human macrophages.

Cationized liposomal keto-mycolic acids isolated from Mycobacterium bovis bacillus Calmette-Guérin induce antitumor immunity in a syngeneic murine bladder cancer model.

Intravesical therapy using Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the most established cancer immunotherapy for bladder cancer. However, its underlying mechanisms are unknown. Mycolic acid (MA), the most abundant lipid of the BCG cell wall, is suspected to be one of the essential active components of this immunogenicity.

Bacillus Calmette-Guérin strain differences as the basis for immunotherapies against bladder cancer.

In the past 40 years, intravesical immunotherapy with Mycobacterium bovis bacillus Calmette-Guérin has been carried out as the most effective treatment for preventing local recurrences and tumor progression of non-muscle-invasive bladder cancer. Bacillus Calmette-Guérin is a family of vaccines derived in 1921 by the in vitro attenuation of Mycobacterium bovis. Subsequently, bacillus Calmette-Guérin seed lots were spread around the world, and both phenotypic and genotypic differences among the strains have been compiled.

Anti-tumor immunity via the superoxide-eosinophil axis induced by a lipophilic component of Mycobacterium lipomannan.

Mycobacterium bovis Bacille Calmette-Guérin (BCG) has been shown to possess potent anti-tumor activity particularly in various animal models, while the cellular and molecular mechanisms underlying its activity are not well understood. We found that lipomannan (BCG-LM), a lipophilic component of the mycobacterial cell envelope, specifically inhibits tumor growth and induces the infiltration of eosinophils at local tumor invasion sites. In contrast, neither lipoarabinomannan (BCG-LAM) nor the cell wall of Mycobacterium bovis BCG (BCG-CW) exerted anti-tumor immunity.

C-Type Lectin Receptor DCAR Recognizes Mycobacterial Phosphatidyl-Inositol Mannosides to Promote a Th1 Response during Infection.

Phosphatidyl-inositol mannosides (PIM) are glycolipids unique to mycobacteria and other related bacteria that stimulate host immune responses and are implicated in mycobacteria pathogenicity. Here, we found that the FcRγ-coupled C-type lectin receptor DCAR (dendritic cell immunoactivating receptor; gene symbol Clec4b1) is a direct receptor for PIM. Mycobacteria activated reporter cells expressing DCAR, and delipidation of mycobacteria abolished this activity.

Middle-aged to elderly women have a higher asymptomatic infection rate with Mycobacterium avium complex, regardless of body habitus.

Mycobacterium avium complex (MAC) pulmonary disease is prevalent in middle-aged to elderly women with a thin body habitus. By comparing the rate of serologically diagnosed asymptomatic MAC infection and body mass index among 1033 healthy subjects, we find that middle-aged to elderly women became infected with MAC, regardless of their body habitus.

Recurrence of disseminated Mycobacterium avium complex disease in a patient with anti-gamma interferon autoantibodies by reinfection.

We report a case of recurrent disseminated Mycobacterium avium complex (DMAC) disease with anti-gamma interferon autoantibodies. To our knowledge, this is the first reported case caused by reinfection with a separate isolate of M. avium.

Mechanism responsible for the antitumor effect of BCG-CWS using the LEEL method in a mouse bladder cancer model.

We previously reported on the development of a water soluble formulation of the cell wall skeleton of BCG (BCG-CWS), a major immune active center of BCG, by encapsulating it into a nanoparticle (CWS-NP). The CWS-NP allowed us to clarify the machinery associated with the BCG mediated anti-bladder tumor effect, especially the roles of bladder cancer cells and dendritic cells (DCs) in the initial step, which remains poorly understood. We show herein that the internalization of BCG-CWS by bladder cancer cells, but not DCs, is indispensable for the induction of an antitumor effect against bladder cancer.

Nanoparticulation of BCG-CWS for application to bladder cancer therapy.

The Mycobacterium bovis Bacille Calmette-Guerin cell wall skeleton (BCG-CWS) could be used to replace live BCG as a bladder cancer drug. However, because BCG-CWS is poorly soluble, has a strong-negative charge, very high molecular weight and heterogeneity in size of tens of μm, it cannot be used in such an application. We report herein on the development of a novel packaging method that permits BCG-CWS to be encapsulated into 166nm-sized lipid particles.

Bacterial sphingophospholipids containing non-hydroxy fatty acid activate murine macrophages via Toll-like receptor 4 and stimulate bacterial clearance.

Sphingobacterium spiritivorum has five unusual sphingophospholipids (SPLs). Our previous study determined the complete chemical structures of these SPLs. The compositions of the long-chain bases/fatty acids in the ceramide portion, isoheptadecasphingosine/isopentadecanoate or isoheptadecasphingosine/2-hydroxy isopentadecanoate, are characteristic.

Tonsilliphilus suis gen. nov., sp. nov., causing tonsil infections in pigs.

A micro-organism resembling members of the genus Dermatophilus, strain W254(T), which was isolated from the submandibular lymph node of a pig, and an additional 16 strains isolated from swine tonsils, were studied to establish their taxonomic status. Although all 17 strains were isolated anaerobically under an atmosphere of 100 % CO2, all of them were aerotolerant anaerobes. The micro-organisms showed at least five cellular morphologies: (i) a radially protrusive thallus, which proliferated into tuber-like cells; (ii) segmentation in both tubers and thallus followed by multilocule formation, (iii) development of coccoid forms in the locules; (iv) a change from the coccoid forms to zoospores; (v) resting cells, which were able to develop into protrusive thalli again.

Pulmonary TCR γδ T cells induce the early inflammation of granuloma formation by a glycolipid trehalose 6,6'-dimycolate (TDM) isolated from Mycobacterium tuberculosis.

We previously showed that formation of pulmonary granulomas in mice in response to a mycobacterial glycolipid, trehalose 6,6'-dimycolate (TDM) is due to the action of TNF-α and not of IFN-γ. However, the mechanisms of formation and maintenance of pulmonary granulomas are not yet clear. The purpose of the present study is to evaluate the mechanisms of granuloma formation by TDM at the early phase.

The effect of passages during Japanese BCG vaccine production on genetic stability and protective efficacy.

Many genetic differences have been found among currently available BCG vaccines. To avoid continued accumulation of phenotypic or genotypic changes in the strains, WHO and most national regulatory authorities request that the vaccine should not be prepared by more than 12 passages from the master seed lot. However, it has recently been reported that genetic changes occur even during the passage for vaccine production.

Lipid phenotype of two distinct subpopulations of Mycobacterium bovis Bacillus Calmette-Guerin Tokyo 172 substrain.

Bacillus Calmette-Guérin (BCG) Tokyo 172 is a predominant World Health Organization Reference Reagent for the BCG vaccine. Recently, the BCG Tokyo 172 substrain was reported to consist of two subpopulations with different colony morphologies, smooth and rough. Smooth colonies had a characteristic 22-bp deletion in Rv3405c of the region of difference (RD) 16 (type I), and rough colonies were complete in this region (type II).

The therapeutic effects of R8-liposome-BCG-CWS on BBN-induced rat urinary bladder carcinoma.

Background: The present gold standard for bladder cancer is Mycobacterium bovis bacillus Calmette-Guérin (BCG) immunotherapy, but serious side-effects are common. We previously reported that C3H/HeN mice vaccinated with a mixture of MBT-2 cells and artificial BCG, octaarginine-modified liposomes incorporating the cell wall of BCG (R8-liposome-BCG-CW), significantly inhibited growth of R8-liposome-BCG-CW pretreated MBT-2 cells. Our aim was to determine if a non-live bacterial agent could be as efficacious as live BCG in a model of bladder cancer.

The liposome-incorporating cell wall skeleton of Mycobacterium bovis bacillus Calmette-Guéin can directly enhance the susceptibility of cancer cells to lymphokine-activated killer cells through up-regulation of natural-killer group 2, member D ligands.

Objective: • To conduct a preclinical evaluation of the ability of natural killer cells to cytolyze bladder cancer cells that were modified to show enhanced expression of natural-killer group 2, member D (NKG2D) ligands by R8-liposome-bacillus Calmette-Guéin (BCG)-cell wall skeleton (CWS) treatment.

Materials And Methods: • The T24 cells and RT-112 cells were co-cultured with R8-liposome-BCG-CWS and BCG for 2, 4, or 6 h, and then the surface expression of NKG2D ligands was analyzed using TaqMan real-time quantitative RT-PCR. • Peripheral blood mononuclear cells were obtained with a conventional preparation kit, and then lymphokine-activated killer (LAK) cells were generated from these purified peripheral blood mononuclear cells via interleukin-2 stimulation.

Bacillus Calmette-Guerin and BCG cell wall skeleton suppressed viability of bladder cancer cells in vitro.

Aim: Bacillus Calmette-Guerin (BCG) is one of therapeutic options for urothelial carcinoma (UC). The objectives of this study were to determine the direct effect of viable or heat-killed BCG and BCG cell wall skeleton (BCG-CWS) on UC cells in vitro.

Materials And Methods: UC cell lines were co-cultured with viable or heat-killed BCG Immunobladder® (Tokyo 172 strain) and BCG-CWS.

Novel rhamnosyltransferase involved in biosynthesis of serovar 4-specific glycopeptidolipid from Mycobacterium avium complex.

Glycopeptidolipids (GPLs) are one of the major glycolipid components present on the surface of Mycobacterium avium complex (MAC) that belong to opportunistic pathogens distributed in the natural environment. The serovars of MAC, up to around 30 types, are defined by the variable oligosaccharide portions of the GPLs. Epidemiological studies show that serovar 4 is the most prevalent type, and the prognosis of pulmonary disease caused by serovar 4 is significantly worse than that caused by other serovars.

Effectiveness of BCG vaccination to aged mice.

Background: The tuberculosis (TB) still increases in the number of new cases, which is estimated to approach 10 million in 2010. The number of aged people has been growing all over the world. Ageing is one of risk factors in tuberculosis because of decreased immune responses in aged people.

Biochemical characteristics among Mycobacterium bovis BCG substrains.

In order to evaluate the biochemical characteristics of 14 substrains of Mycobacterium bovis bacillus Calmette Guérin (BCG) - Russia, Moreau, Japan, Sweden, Birkhaug, Danish, Glaxo, Mexico, Tice, Connaught, Montreal, Phipps, Australia and Pasteur - we performed eight different biochemical tests, including those for nitrate reduction, catalase, niacin accumulation, urease, Tween 80 hydrolysis, pyrazinamidase, p-amino salicylate degradation and resistance to thiophene 2-carboxylic acid hydrazide. Catalase activities of the substrains were all low. Data for nitrate reduction, niacin accumulation, Tween 80 hydrolysis, susceptibility to hydrogen peroxide and nitrate, and optimal pH for growth were all variable among these substrains.

Isolation and identification of arabinose mycolates of Cell Wall Skeleton (CWS) derived from Mycobacterium bovis BCG Tokyo 172 (SMP-105).

A unique hydrolysis method using a two-layer solution, consisting of diluted hydrochloric acid and toluene was developed to isolate whole arabinose mycolates from the cell wall skeleton of Mycobacterium bovis BCG Tokyo 172 (SMP-105) in order to reveal its pivotal role in enhancing immune responses against tumors.

Serodiagnostic contributions of antibody titers against mycobacterial lipid antigens in Mycobacterium avium complex pulmonary disease.

Background: Although the incidence of pulmonary tuberculosis is decreasing, the number of immunocompetent patients with Mycobacterium avium complex (MAC) pulmonary disease is steadily increasing. Therefore, albeit not contagious, MAC pulmonary disease needs to be diagnosed rapidly and accurately. We examined the serodiagnostic contributions of serum immunoglobulin G antibody titers against the species-specific and -common mycobacterial lipid antigens in the diagnosis of MAC pulmonary disease.

Comparable studies of immunostimulating activities in vitro among Mycobacterium bovis bacillus Calmette-Guérin (BCG) substrains.

During the serial passage of Mycobacterium bovis bacillus Calmette-Guérin (BCG) in different countries after initial seed distribution from the Pasteur Institute, specific insertions and deletions in the genome among BCG substrains were observed and speculated to result in differences in immunological activities. 'Early-shared strains' of BCG (Russia, Moreau, Japan, Sweden, Birkhaug), distributed by the Pasteur Institute, which conserve three types of mycolate (alpha, methoxy, keto) in cell wall, exhibited stronger activities of induction of nitric oxide, interleukin-1beta (IL-1beta), IL-6, IL-8, IL-12 and tumor necrosis factor (TNF)-alpha, from human epithelial cell line A549, human myelomonocytic cell line THP-1 and mouse bone marrow cells in the presence of interferon-gamma (IFN-gamma) than did 'late-shared strains' of BCG (Danish, Glaxo, Mexico, Tice, Connaught, Montreal, Phipps, Australia, Pasteur). The stronger induction of IL-12 and TNF-alpha in the presence of IFN-gamma was also observed by trehalose 6,6'-dimycolate (TDM) extracted from BCG-Japan than by TDM from BCG-Connaught, which lacks the methoxymycolate residue.