Jagged2-γδT17 is Regulated by Mycobacterium Vaccae in Asthmatic Mice

Background: Mycobacterium vaccae nebulization imparted protective effect against asthma in a mouse model. The Jagged2-γδT17 signal transduction pathway plays an important role in bronchial asthma. However, the effect of M. vaccae nebulization on the Jagged2-γδT17 signal transduction pathway in mouse models of asthma remains unclear. Methods: In total, 30 female C57 mice were randomized to normal control (group a), asthma control (group b), M. vaccae nebulization prevention,and M. vaccae nebulization treatment (group d) groups. Asthma mice models were created using ovalbumin (OVA). The Notch signaling pathway was blocked by DAPT inhibitors. Airway hyperreactivity (AHR) was measured by noninvasive lung function tests. Histopathological analyses using blue-periodic acid Schiff along with hematoxylin and eosin were performed. Immunohistochemistry, immunofluorescence, and a Western blotting assay allowed for the detection of lung protein expressions, while spleen expressions of IL-17+γδT+ cytokines were assessed with FLOW cytometry. One-way analysis of variance for within-group comparisons, the least significant difference t-test or Student-Newman-Keuls test for intergroup comparisons, and the nonparametric rank sum test for analysis of airway inflammation scores were used in the study. Results: Asthmatic mice models demonstrated downregulated Notch signaling pathway activation and decreased γδT cells and IL-17 cytokine secretion. There was also increased Jagged2 protein expression which correlated positively with γδT+IL-17+ secretion. In asthmatic mice, the expressions of Jagged2 and γδT17, along with airway inflammation and airway reactivity, were all decreased after M. vaccae exposure (p<0.05). Conclusion: The Notch signaling pathway contributed towards asthma initiation and progression by facilitating γδT cells and IL-17 cytokines production. Inhaled M. vaccae led to a significant decrease in Jagged2 and γδT17 expressions in asthmatic mice, indicating its utility in asthma prevention.

BIOLOGICAL PROPERTY OF THE ECOLOGICAL CULTURES MYCOBACTERIUM VACCAE

Prokaryotes of the genus Mycobacterium occupy an important evolutionary and historical place in the system of microorganisms of prokaryotic and eukaryotic organization in the Earth's biosphere. These are the most ancient microorganisms that have passed a long historical path of mutual adaptation with the evolving biosphere over billions of years. Antiquity of origin is very important in the process of developing a stable and at the same time adaptive genomic apparatus, which provides genetic information support for the very diverse physiological needs of a carrier of a given genotype in the constantly changing conditions of the environment of existence and creating competitive advantages over similar carriers of gene programs in the limited space of a specific ecosystem. A significant species diversity of prokaryotes of the genus Mycobacterium is a consequence of the wide divergence of the ancestral ancestor species of the sapronous type in the process of soil formation from lithotrophic forms to the highest degree of bioparasitism in the form of highly specialized infectious pathogens with pronounced pathogenicity, invasiveness and the potential ability to take root in an internal macroorganism and an extremely effective antagonist the immune system of supervision over the genetic homeostasis of a macroorganism with a paradigm of tolerance to its genetically own and categorical intolerance to carriers of geneticaly foreign information. Only a small number of mycobacterial species have adapted to the internal environment of eukaryotic macroorganisms as a result of the suppression of the protective mechanisms of the lymphoid system by pathogenic factors. The path of symbiotic relationships, mutually beneficial interpopulation, turned out to be much more effective. As a result, a dynamic microbial organ arose - the microbiota of the large intestine, inhabited by indigenous and transient microbionts, among which Mycobacterium vaccae occupy an important place. Ecological strains "K", "N", "Gk", "Gn" of Mycobacterium vaccae were isolated and identified by conventional bacteriological methods. Examined their basic properties. The strains possessed morpho-tinctorial, cultural and biochemical properties characteristic of the species, were apathogenic for laboratory animals when administered parenterally, caused short-term sensitization to mycobacterial antigens and induced antitilogenesis. In broiler chickens on fattening with oral feeding of live culture, they stimulated metabolism, increased weight gain and increased the protective properties of the nonspecific link of the immune reactivity of the macroorganism. Strains of atypical mycobacteria were isolated on the territory of one poultry farm and had similar biocharacteristics; they are suitable for use as probiotics to increase nonspecific resistance, stimulate the physiological functions of the macroorganism, increase weight gain and improve feed payment.

Effects of Immunization With the Soil-Derived Bacterium Mycobacterium vaccae on Stress Coping Behaviors and Cognitive Performance in a “Two Hit” Stressor Model

Previous studies demonstrate that Mycobacterium vaccae NCTC 11659 (M. vaccae), a soil-derived bacterium with anti-inflammatory and immunoregulatory properties, is a potentially useful countermeasure against negative outcomes to stressors. Here we used male C57BL/6NCrl mice to determine if repeated immunization with M. vaccae is an effective countermeasure in a “two hit” stress exposure model of chronic disruption of rhythms (CDR) followed by acute social defeat (SD). On day –28, mice received implants of biotelemetric recording devices to monitor 24-h rhythms of locomotor activity. Mice were subsequently treated with a heat-killed preparation of M. vaccae (0.1 mg, administered subcutaneously on days –21, –14, –7, and 27) or borate-buffered saline vehicle. Mice were then exposed to 8 consecutive weeks of either stable normal 12:12 h light:dark (LD) conditions or CDR, consisting of 12-h reversals of the LD cycle every 7 days (days 0–56). Finally, mice were exposed to either a 10-min SD or a home cage control condition on day 54. All mice were exposed to object location memory testing 24 h following SD. The gut microbiome and metabolome were assessed in fecal samples collected on days –1, 48, and 62 using 16S rRNA gene sequence and LC-MS/MS spectral data, respectively; the plasma metabolome was additionally measured on day 64. Among mice exposed to normal LD conditions, immunization with M. vaccae induced a shift toward a more proactive behavioral coping response to SD as measured by increases in scouting and avoiding an approaching male CD-1 aggressor, and decreases in submissive upright defensive postures. In the object location memory test, exposure to SD increased cognitive function in CDR mice previously immunized with M. vaccae. Immunization with M. vaccae stabilized the gut microbiome, attenuating CDR-induced reductions in alpha diversity and decreasing within-group measures of beta diversity. Immunization with M. vaccae also increased the relative abundance of 1-heptadecanoyl-sn-glycero-3-phosphocholine, a lysophospholipid, in plasma. Together, these data support the hypothesis that immunization with M. vaccae stabilizes the gut microbiome, induces a shift toward a more proactive response to stress exposure, and promotes stress resilience.

Immunization with a heat-killed bacterium, Mycobacterium vaccae NCTC 11659, prevents the development of cortical hyperarousal and a PTSD-like sleep phenotype after sleep disruption and acute stress in mice

Study Objectives Sleep deprivation induces systemic inflammation that may contribute to stress vulnerability and other pathologies. We tested the hypothesis that immunization with heat-killed Mycobacterium vaccae NCTC 11659 (MV), an environmental bacterium with immunoregulatory and anti-inflammatory properties, prevents the negative impacts of five days of sleep disruption on stress-induced changes in sleep, behavior, and physiology in mice. Methods In a 2x2x2 experimental design, male C57BL/6N mice were given injections of either MV or vehicle on days –17, –10, and –3. On days 1-5, mice were exposed to intermittent sleep disruption, whereby sleep was disrupted for 20 hours per day. Immediately following sleep disruption, mice were exposed to 1-hour social defeat stress or novel cage (control) conditions. Object location memory (OLM) testing was conducted 24 hours after social defeat, and tissues were collected six days later to measure inflammatory markers. Sleep was recorded using electroencephalography (EEG) and electromyography (EMG) throughout the experiment. Results In vehicle-treated mice, only the combination of sleep disruption followed by social defeat (double hit): 1) increased brief arousals and NREM beta (15-30Hz) EEG power in sleep immediately post-social defeat compared to baseline; 2) induced an increase in the proportion of rapid-eye-movement (REM) sleep and number of state shifts for at least 5 days post-social defeat; and 3) induced hyperlocomotion and lack of habituation in the OLM task. Immunization with MV prevented most of these sleep and behavioral changes. Conclusions Immunization with MV ameliorates a stress-induced sleep and behavioral phenotype that shares features with human posttraumatic stress disorder.

Alzheimer’s Disease: Protective Effects of Mycobacterium vaccae, a Soil-Derived Mycobacterium with Anti-Inflammatory and Anti-Tubercular Properties, on the Proteomic Profiles of Plasma and Cerebrospinal Fluid in Rats

Background: Alzheimer’s disease (AD) is an inflammatory neurodegenerative disease that may be associated with prior bacterial infections. Microbial “old friends” can suppress exaggerated inflammation in response to disease-causing infections or increase clearance of pathogens such as Mycobacterium tuberculosis, which causes tuberculosis (TB). One such “old friend” is Mycobacterium vaccae NCTC 11659, a soil-derived bacterium that has been proposed either as a vaccine for prevention of TB, or as immunotherapy for the treatment of TB when used alongside first line anti-TB drug treatment. Objective: The goal of this study was to use a hypothesis generating approach to explore the effects of M. vaccae on physiological changes in the plasma and cerebrospinal fluid (CSF). Methods: Liquid chromatography-tandem mass spectrometry-based proteomics were performed in plasma and CSF of adult male rats after immunization with a heat-killed preparation of M. vaccae NCTC 11659 or borate-buffered saline vehicle. Gene enrichment analysis and analysis of protein-protein interactions were performed to integrate physiological network changes in plasma and CSF. We used RT-qPCR to assess immune and metabolic gene expression changes in the hippocampus. Results: In both plasma and CSF, immunization with M. vaccae increased proteins associated with immune activation and downregulated proteins corresponding to lipid (including phospholipid and cholesterol) metabolism. Immunization with M. vaccae also increased hippocampal expression of interleukin-4 (IL-4) mRNA, implicating anti-inflammatory effects in the central nervous system. Conclusion: M. vaccae alters host immune activity and lipid metabolism. These data are consistent with the hypothesis that microbe-host interactions may protect against possible infection-induced, inflammation-related cognitive impairments.

The first case of Mycobacterium vaccae sepsis in a non-Hodgkin lymphoma patient: biological understandings and clinical consequencies

Mycobacterium vaccae is a rapidly growing nonpathogenic species of the Mycobacteriaceae family of bacteria that can cause pulmonary and disseminated disease in particular in immunocompromised individuals. Here we describe a first case of matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass-spectrometry (MS) identification of this pathogen in a patient with non-Hodgkin’s lymphoma during chemoimmunotherapy salvage treatment, and its impact on clinical decision making.