Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026918 (Mycobacterium)
 52,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acid-fast staining is broadly used for the detection of mycobacteria in smears or pathological preparations, but it does not distinguish viable and non-viable bacteria. Enzymatic hydrolysis of fluorescein diacetate (FDA) was reported as a tool to detect viable mammalian cells or protozoa. We have applied this method to mycobacteria samples to detect viable or non-viable bacteria in the smear. Mycobacterium bovis BCG (Tokyo), 20 mg/ml suspension of standard vaccine, was used as the sample of viable bacteria. A part of the same suspension was heated at 100 degrees C for 30 min and used as the sample of non-viable bacteria. Three samples, viable, non-viable, and 1:1 mixture of the two, were stained with acid-fast staining and FDA-EB (ethidium bromide) mixture, respectively. For FDA/EB staining, stock solution of FDA (5 mg/ml acetone) was diluted 1:50 in PBS and 25 microliters of FDA and 25 microliters of EB (20 micrograms/ml PBS) were mixed with 50 microliters of bacterial suspension. Preparations were observed with either light or fluorescein microscope. Living bacteria were stained in yellow green in FDA/EB staining while non-viable bacteria were red. Mixed sample of live and dead bacilli showed differential staining with green or red in FDA/EB staining, but no difference was shown in acid-fast staining between viable and non-viable bacteria.
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PMID:[Detection of viable or non-viable mycobacteria by hydrolysis of fluorogenic substrate]. 169 50

Several methods of coating whole cells of Mycobacterium tuberculosis H37 RV to ELISA microtitre plates were compared with the aim of developing an ELISA screening assay for murine monoclonal antibodies in culture supernatants and human antibodies in patient sera. Undercoats of nylon or poly-L-lysine were compared to polystyrene as adsorptive surfaces for the bacteria, the effect of increased ionic strength and iclusion of SDS in the coating buffer measured, and methanol (70%) and glutaraldehyde (5%) investigated for their efficiency as fixatives of the bacterial monolayers. The results suggest PBS as a satisfactory coating buffer for the bacterial cells on polystyrene, and 70% methanol the preferred fixative for the dried antigen-coated plates.
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PMID:Polystyrene, poly-L-lysine and nylon as adsorptive surfaces for the binding of whole cells of Mycobacterium tuberculosis H37 RV to ELISA plates. 212 47

An antigen was purified from Mycobacterium tuberculosis H37Ra culture filtrate by immunoabsorbent affinity chromatography with CNBr-activated sepharose 4B column coupled with pooled gamma-globulin fraction from patients with active tuberculosis. The column was washed extensively with PBS and eluted with 3M sodium thiocyanate. Peak fractions were pooled and used as coating antigen in an ELISA. Sera from 86 normal subjects and 54 patients with active tuberculosis were tested against the immunoabsorbed antigen by ELISA with biotin-conjugated anti-human globulin and avidin-peroxidase reagents. At a selected "cut-off" dilution of 320, 49 (91%) of 54 sera from active cases and 8 (9.3%) of 86 sera from normal subjects gave positive test results--a sensitivity and specificity each of 91%, compared with our previous results of sensitivity 75% and specificity 83% with PPD as antigen.
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PMID:Improved ELISA with immunoabsorbent-purified mycobacterial antigen for serodiagnosis of tuberculosis. 250 85

Circulating immune complexes (CIC) were first measured in lepromatous patients (LL) by the 125I-C1q binding assay and the polyethylene glycol (PEG) precipitation test. High levels were found by both methods (95 and 90% of positives, respectively). LL-CIC were investigated for the presence of neural antigens. CIC were precipitated in 3.5% PEG, filtered through protein A-Sepharose affinity chromatography, eluted with glycine-HCl, pH 2.8, and washed with PBS; fractions after CIC dissociation were studied by SDS-PAGE and Western blotting. The LL-CIC PEG precipitates and the glycine-HCl eluates were positive in 76 and 71% respectively against anti-myelin basic proteins (MBP) monoclonal antibody, showing a single band at 15-25 kDa similar to the one obtained incubating MBP with anti-MBP. No reaction was detected with CIC-PBS fractions; strips were incubated with other anti-neural antibodies such as anti-glial fibrillary acidic proteins, anti-S-100, and anti-neurofilaments, without any reactivity. Our results demonstrate that LL-CIC contain MBP as an antigen; its significance could be related to the pathogenesis of leprosy since the liberation of MBP after Mycobacterium leprae nerve damage may elicit anti-MBP autoantibodies to myelin breakdown, which reacts with peripheral nerve MBP inducing CIC formation. This mechanism may be important in demyelination and destruction of nerve in leprosy.
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PMID:Identification of myelin basic proteins in circulating immune complexes associated with lepromatous leprosy. 751 Oct 83

An acid-fast staining can detect mycobacteria in clinical specimens rapidly and specifically. It equally stains living and dead bacteria. It would be of more clinical use if the viability of mycobacteria in a sample was determined by the staining. In the present paper, the problems of FDA/EB staining, which detects live or dead bacteria, were solved by establishing a new technique, a slide-method. An air-dried smear of Mycobacterium bovis BCG (Tokyo 172) on a glass slide was covered by a filter paper fully soaked in the staining solution (500 micrograms FDA and 40 micrograms EB per ml PBS). This was kept in an incubator at 37 degrees C for 20 min. The filter paper was removed after incubation and the slide was examined using a fluorescent microscope with a blue filter. Live bacteria were stained greenish yellow taking the FDA stain in while dead bacteria were stained red with EB. This new slide technique eliminated the problems associated with FDA/EB staining. Moreover, stained smears appeared to be more stable compared with the conventional tube method. To overcome the biohazard problems in smear examination of tubercle bacilli, heating of the slides on a heat block at 100 degrees C for 20 min or passing air dried smears in a flame 5 to 30 times was tried to kill the bacteria. The heat-treated slides were stained with FDA/EB and the number of green and red bacteria were counted. Samples of the smeared bacteria were taken after heating and cultured on a solid medium to determine the presence of any colony-forming unit. It was found that no CFU was observed after heating and the morphology of the stained sample was the same to that before heating. These facts suggest that the above mentioned method is a simple, safe yet inexpensive diagnostic tool for mycobacterial clinical specimens.
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PMID:[Development of slide-method to distinguish alive and dead mycobacteria by fluorescent staining--a trial for solving the biohazard problem in TB laboratories]. 1048 28

The detection of pathogenic bacteria directly in human fecal specimens by PCR, requires removal of PCR-inhibitory substances. To investigate whether five different macroporous filters (polypropylene, nylon, polyester, polyethylene, fluorocarbon) could retain polysaccharides, major PCR inhibitors, an in vitro model and human fecal samples were used. The in vitro model consisted of Xanthum gum solutions (3 mg/ml PBS), a bacterial polysaccharide, to which Helicobacter pylori cells were added. Fecal samples from healthy volunteers were spiked with H. pylori and Mycobacterium paratuberculosis cells. Polysaccharide concentrations were significantly reduced only by the polypropylene but not by the other filters. Accordingly, both Xanthum gum solutions and spiked fecal specimens became PCR positive only after filtration with the polypropylene filter. We conclude that this filter can be used to prepare a bacterial DNA template suitable for PCR analysis from human feces.
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PMID:Use of macroporous polypropylene filter to allow identification of bacteria by PCR in human fecal samples. 1067 Jul 72

Effects of prostaglandin E2 (PGE2) and indomethacin, an inhibitor of PGE2 oxygenase, on primary and secondary antibody (Ab) responses to Mycobacterium butyricum protein or keyhole limpet hemocyanin (KLH) were studied in growing layer hens. Immunizations at 35 and 70 d of age were accompanied by immunomodulating treatments with PGE2, indomethacin, or PBS. In addition, we studied effects of various doses of indomethacin and PGE2 on mitogen-induced T-cell proliferation in vitro. Secondary Ab responses to KLH were enhanced by administration of indomethacin at secondary immunization and, to a lesser extent, by PGE2 administration at secondary immunization. Primary Ab responses to M. butyricum tended to decrease by administration of either PGE2 or indomethacin. Secondary Ab responses to M. butyricum were affected by administration of both PGE2 and indomethacin at primary immunization. Prostaglandin E2 increased phytohemagglutinin (PHA)-induced lymphocyte proliferation. Indomethacin decreased Concanavalin A (ConA)- and PHA-induced lymphocyte proliferation. The net effect of indomethacin on the Ab response could not be explained by inhibition of PGE2 oxygenase only. Our data rather suggest an inhibition by indomethacin of other immunosuppressing factors derived from arachidonic acid. We concluded that polyunsaturated fatty acid-derived products might especially affect secondary antibody responsiveness. This finding may depend on inhibition or enhancement of T-cell responsiveness. Consequently, immunomodulation by dietary polyunsaturated fatty acids may have profound effects at secondary rather than at primary exposure to pathogens.
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PMID:Immunomodulatory effects of indomethacin and prostaglandin E2 on primary and secondary antibody response in growing layer hens. 1090 Nov 92

The effects of linoleic (LA)- and linolenic acid (LNA)-enriched diets on humoral and in vivo cellular immune responses to keyhole limpet hemocyanin (KLH)-dinitrophenyl (DNP) and Mycobacterium butyricum were studied in growing layer hens. Pullets were fed one of three diets: a control, LA enriched, or LNA enriched. Pullets were assigned to one of three immunization treatments: KLH-DNP, M. butyricum, or PBS. The LA-enriched diet enhanced the antibody response to KLH in pullets immunized with KLH-DNP. On the other hand, the antibody response to M. butyricum in M. butyricum-immunized birds was decreased by feeding an LA-enriched diet. In vitro lymphocyte proliferation in the presence of Concanavalin A was affected by the interaction between diet and immunization. Neither cutaneous hypersensitivity to KLH nor to M. butyricum was affected by the diet. The BW gain before immunization was not affected by the diet, but after immunization, the LA-enriched diet enhanced growth in birds immunized with M. butyricum. Diets had various effects on organ weights. We concluded that dietary linoleic acid enrichment of the diet has an antigen-dependent divergent effect on the antibody response. The dietary LNA effect on the antibody response is less pronounced and is opposite to that of the LA effect.
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PMID:Dietary linoleic acid divergently affects immune responsiveness of growing layer hens. 1094 78

IL-18 is an important cytokine in autoimmune and inflammatory diseases through the induction of IFN-gamma, TNF-alpha, and IL-1. We report herein that collagen-induced arthritis (CIA) in mice is inhibited by treatment with murine IL-18 binding protein (mIL-18BP). CIA was induced in DBA/1J mice by the injection of bovine type II collagen (CII) in IFA with added Mycobacterium tuberculosis on days 0 and 21. The mice were then treated for 3 wk with PBS or with two doses of mIL-18BP (0.5 and 3 mg/kg) as a fusion protein with the Fc portion of murine IgG1. Both the clinical disease activity scores and the histological scores of joint damage were reduced 50% in mice treated with either dose of mIL-18BP. Proliferation of CII-stimulated spleen and lymph node cells as well as the change in serum levels of IgG1 and IgG2a Ab to collagen between days 21 and 42 were decreased in mice treated with mIL-18BP. The production of IFN-gamma, TNF-alpha, and IL-1beta in cultured spleen cells was reduced by in vivo treatment with low dose, but not high dose, mIL-18BP. FACS analysis showed a slight decrease in NK cells and an increase in CD4(+) T cells in spleens of mice treated with mIL-18BP. The steady state mRNA levels of IFN-gamma, TNF-alpha, and IL-1beta in isolated joints were all decreased in mice treated with both doses of mIL-18BP. The mechanisms of mIL-18BP inhibition of CIA include reductions in cell-mediated and humoral immunity to collagen as well as decreases in production of proinflammatory cytokines in the spleen and joints.
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PMID:Mechanisms of inhibition of collagen-induced arthritis by murine IL-18 binding protein. 1257 81

Inflammation occurring consequent to vessel injury is thought to play an important role in atherosclerosis and restenosis. Autoimmunity to HSP65 has been shown to accelerate early atherogenesis in rabbits and mice, whereas in humans epidemiological data support this contention. In the current study, we explored the possibility of HSP65 influencing the extent of neointimal growth in the rat carotid injury model. Rats were either immunized with recombinant mycobacterial HSP65, heat killed preparation of Mycobacterium tuberculosis (MT), or with PBS, all emulsified in incomplete Freund's adjuvant. Animals were boosted with a similar protocol 3 weeks following the primary immunization and 2 weeks later carotid injury was applied in all animals by balloon inflation. Upon sacrifice 2 weeks later, sera were obtained for measurement of anti-HSP65 antibodies by ELISA, splenocytes were assessed for proliferative response to in vitro priming with HSP65, and carotid arteries were removed for evaluation of neointimal growth. Rats immunized with HSP65 exhibited a brisk and sustained humoral immune response to HSP65, and cellular immunity was also evident by thymidine uptake to splenocytes primed with the respective protein. Neointimal/medial ratio was significantly increased in HSP65 immunized rats, in comparison with MT injected and control animals. In conclusion, immunity to HSP65 can play a role in accelerating restenosis following arterial injury. These results should be further investigated in humans as they may provide a possible link between infections and restenosis/accelerated arteriosclerosis.
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PMID:Immunity to heat shock protein 65--an additional determinant in intimal thickening. 1273 84


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