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)

The sensitivity and specificity of an ELISA for the detection of bovine IgG anti-Mycobacterium bovis antibodies were 73.6% and 94.1%, respectively, as determined in 53 bacteriologically confirmed tuberculous cattle and 101 healthy cattle from a tuberculosis-free area. In addition, the results of ELISA and tuberculin tests in 149 cattle were compared with those of subsequent necropsy studies. Both tests failed to detect 2 animals with tuberculous lesions and positive culture; 3/12 cattle with M. bovis isolation and no lesions, and 2/7 with atypical mycobacterial infection reacted to tuberculin, but none had antibodies; in 128 cattle with neither lesions nor mycobacterial isolation, 6 were tuberculin reactors and 7 others had antibodies. Negative results were obtained by ELISA in 21/22 paratuberculous cattle. Antibodies were not detected in 88.9% to 96.4% of 697 cattle from two tuberculin negative herds of an endemic area. In a herd with proved M. bovis infection, distribution of seropositive animals in tuberculin and non-tuberculin reactors was similar. Antibody responses to cutaneous tuberculin stimuli were observed in 4 experimentally infected cattle, but only in 2/10 healthy controls after repeated PPD stimuli. Nine controls which had either received a single tuberculin dose or none showed no increase in antibody levels. The low sensitivity of this ELISA limits its usefulness as a diagnostic tool for bovine tuberculosis eradication campaigns. However, it could be helpful in epidemiological surveillance if its efficiency to identify infected herds is demonstrated.
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PMID:Further evaluation of an indirect enzyme-linked immunosorbent assay for the diagnosis of bovine tuberculosis. 218 79

A group of 52 untreated leprosy patients were examined to determine the relationship between local and systemic immunological parameters across the clinico-pathological spectrum. The Ridley-Jopling classification, bacterial index (BI), and granuloma fraction (GF) were assessed in biopsies from 40 cases. The densities of apoptoses, mitoses, and plasma cells were also measured. Systemic immunity to mycobacteria was assessed by skin tests with leprosin A and PPD, and by measurement of the serum antibody responses to Mycobacterium leprae, M. tuberculosis, and M. scrofulaceum. The serum responses to phenolic glycolipid-I (PGL-I) of M. leprae was assessed using a glycoconjugate which mimics an immunodominant epitope. The serum antibody levels and skin test results showed the expected inverse relationship. The BI within lesions showed an inverse correlation with the skin test results, but none of the other histological parameters studied showed a significant relationship with the other measurements of systemic immunity. Our findings suggest that the inverse relationship between delayed-type hypersensitivity and humoral immunity in leprosy patients, which is strong in groups of patients across the leprosy spectrum, is less strong in individual patients than is often thought. The lack of correlation of many histological and systemic parameters suggests that local factors modulate systemic immunity in the pathogenesis of leprosy lesions.
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PMID:A quantitative study of the relationship between systemic and histological parameters of immunity in individual leprosy patients. 219 17

Mycobacterium avium Mino grows well in the lung, spleen or liver of susceptible mice, such as C57BL/6, C57BL/10, and B10 congenics. Infection with Mino inhibited the induction of delayed-type hypersensitivity (DTH) to BCG in the mouse receiving subcutaneous injection of BCG 2 weeks later. Post-infection with Mino did not affect DTH to BCG already established. Preceding infection with avirulent strains of atypical mycobacteria weakly suppressed the induction of DTH by BCG. On the other hand, Mino infection did not affect DTH to SRBC. DTH to Mino and DTH to BCG detected by PPD-I and PPDs hardly showed cross-reactivity. These results suggest that tuberculin skin reaction after BCG vaccination could be suppressed by the infection with atypical mycobacteria in humans, especially where these bacterial infections are prevailing.
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PMID:[Effect of atypical mycobacterial infection on the cell-mediated immunity induced by Mycobacterium bovis BCG in mice. I. Suppression of delayed-type hypersensitivity]. 223 36

The standard tuberculin skin test has been known as the prototype of delayed type hypersensitivity testing which is mediated by T cells and macrophages and plays an important role in the pathogenesis of tuberculosis. Tuberculosis is indeed a chronic infectious disease, but variation in the host immune responses to tubercle bacilli results in the various clinical manifestations of the disease ranging from an immunologically hyperreactive state observed in pleural fluid lymphocytes in tuberculous pleurisy to an almost totally unresponsive state observed in those severely ill with refractory tuberculosis. In tuberculous pleurisy, T cells in pleural fluid respond remarkably in vitro to PPD tuberculin whereas T cells in peripheral blood responded poorly to PPD stimulation. Compartmentalization of PPD-reactive T cells in the pleural fluid and immunosuppression by T cells and/or macrophages in the peripheral blood were responsible for this immunological difference observed between the lymphocytes in pleural fluid and those in peripheral blood of tuberculous pleurisy. In advanced, drug-resistant tuberculosis as well as in nontuberculous mycobacterial infection, the proliferative responses of T cells in vitro to PPD stimulation were impaired. This depressed T cell response was due to depressed interleukin-2 (IL-2) production and not due to depressed IL-2 responsiveness. Therefore, the addition of exogenous IL-2, returned the depressed PPD-induced lymphocyte proliferation in vitro in these patients to the level of the response observed in lymphocytes from patients with newly-diagnosed tuberculosis. Our results suggest that recombinant IL-2 offers a novel approach to the therapy of advanced, drug-resistant tuberculosis and nontuberculous mycobacterial infection. Preliminary clinical trials of immunotherapy with recombinant IL-2 reveals the effectiveness of this therapy and encourages us to extend the trial to a larger scale. Tubercle bacilli have various biological activities. Research on tuberculosis and tubercle bacilli have contributed much to the progress of biochemistry, pathology and immunology. Mycobacterium is a fascinating organism, which now presents another big appeal to those studying immunology: Study of immunological interaction between gamma delta T cells and the highly conserved protein in mycobacteria, HSP, heat shock protein will contribute to the elucidation of the mechanism of immunological surveillance and the mechanism of autoimmune diseases. In addition, it will also contribute to the development of a new mycobacterial vaccine which will give direct, protective immunity against tuberculosis.
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PMID:[Clinical immunology of tuberculosis]. 223 38

Ten bull-calves were infected with 10(8) viable cells of Mycobacterium paratuberculosis per os. During the 400-day period of observation faecal and blood samples were taken from animals at 30-day intervals. Faecal samples were examined microscopically, blood samples by the CFT, AGID and LST tests. Intradermal allergic tests were carried out at PI (post infection) days 92, 217, 336, using mammalian, avian and johnin PPD. In the period of study, these efficiency indices showed fluctuations characteristic of the given tests. In the period between PI day 160 and 400 fifteen biochemical parameters were measured monthly, TRP, ALP, TRIG and CHOL were reduced by day 400, pointing to disorders of digestion and absorption. Increased activities of CK, ALD, LDH, alpha-HBDH and ALT indicated skeletal muscle and/or liver damage in the first place. Serum CK, ALD activities and TRIG and TRP concentrations may serve as useful complementary values to the specific diagnosis of paratuberculosis, particularly in the advanced stage of the disease.
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PMID:Some diagnostic features of the pathogenesis of bovine paratuberculosis (Johne's disease) and serum biochemical changes after oral reinfection. 238 84

A positive Mitsuda skin test for delayed type hypersensitivity to Mycobacterium leprae is associated with a high level of protection against lepromatous leprosy, while the value of tuberculin sensitivity in leprosy is less pronounced. Cutaneous lymphocytes, isolated from the Mitsuda reaction of a PPD-positive individual not previously exposed to M. leprae, were cloned with Dharmendra lepromin and analysed for antigen specificity. Thirteen lepromin-responsive cell lines were derived, with greater than 95% certainty that the number of true clones was at least five and the number of functionally monoclonal lines at least seven. All lepromin-responsive clones proliferated in response to PPD as well, implying that PPD-responsive cells can fulfill the helper T cell function required for the in vivo Mitsuda reaction.
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PMID:Evidence that the Mitsuda reaction to Mycobacterium leprae can be mediated by lymphocytes responsive to Mycobacterium tuberculosis. 245 70

A high molecular weight protein from Mycobacterium tuberculosis (M. tuberculosis) has been identified, that is recognized by peripheral blood mononuclear cells from several tuberculous patients and by a T cell clone derived from a patient with tuberculous pleurisy. Purification of this fraction demonstrated biological activity to reside in a 180-kDa protein component. This mycobacterial protein appears to exist in some, but not all mycobacteria as the clone reacts to M. tuberculosis, BCG M. kansasii, M. flavescens and M. fortuitum, but not to M. intracellulare, M. scrofulaceum or a variety of gram-positive or gram-negative bacteria, or to PPD. Specific anti-genic challenge of the T cell clone in the presence of irradiated antigen presenting cells results in proliferation and interleukin-2 (IL-2) production. Proliferation is restricted to HLA Class II antigens as antigenic recognition occurs only in the presence of either one of the two parental DR haplotypes. Peripheral blood mononuclear cells from several other patients with pulmonary tuberculosis also proliferate in response to this antigen, emphasizing the relevance of T cell cloning techniques in identifying important mycobacterial antigens.
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PMID:A 180-kilodalton protein from Mycobacterium tuberculosis defined by a human T cell clone. 248 13

Dendritic cell (DC)-enriched cell populations from anergic lepromatous leprosy (LL) patients were found to be several-hundred-fold more efficient than monocytes (MO) in promoting antigen-induced T cell responses in autologous accessory + T cell cultures. Whereas, the use of autologous monocytes over a wide concentration range failed to stimulate Mycobacterium leprae-induced T cell proliferation, DC at concentrations as low as 0.1% induced significant proliferation in 9/15 and interferon gamma production in 14/15 LL patients. Four of the LL patients who failed to show proliferation were, however, able to secrete interferon gamma in the same T cell + DC co-cultures. DC were able to present particulate leprae antigens to autologous T cells. This preference for DC as an accessory cell was not shown when the cross-reacting antigen PPD was used in parallel co-cultures. Though tuberculoid leprosy patients showed some improvement in T cell proliferation with DC as compared to MO constituted co-cultures, this was not statistically significant. These results suggest that there is a heterogeneity in accessory cell requirement across the leprosy spectrum and that many lepromatous patients possess M. leprae-reactive functional T cells.
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PMID:Accessory cell heterogeneity in lepromatous leprosy; dendritic cells and not monocytes support T cell responses. 250 76

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

The ELISA has been extensively evaluated as a serodiagnostic method for tuberculosis. However, there is scarce information about its application to cases that cannot be diagnosed by microscopic examination: those with closed lesions or undergoing early stages of the disease. Since a reliable serological test might substantially contribute to their prompt detection, the objective of the present study was to determine the diagnostic value of an ELISA applied to adult smear-negative cases of tuberculosis. Sera from 235 patients with active tuberculosis--176 pulmonary and 59 extrapulmonary cases--and 181 control subjects were tested for IgG antibodies to PPD by ELISA. Eleven cases of non tuberculous mycobacterial (MOTT) disease and 33 cases of mycosis were also included in this group. With the adopted cut-off value, 73.9% (105/142) of smear positive and 52.7% (49/93) of smear negative tuberculosis cases, were correctly classified. Particularly in the latter, the test was positive in 55.2% (32/58) of patients with positive cultures for Mycobacterium tuberculosis and in 48.6% (17/35) of patients diagnosed by clinical, radiological and or histopathological findings. No antibody activity was demonstrated in 92.7% of sera from the control population which included 92 healthy volunteers, 32 non tuberculous diseased subjects and 13 household contacts of smear-positive cases. Among those control subjects who were skin tested, ELISA results were not related to the tuberculin reactivity: 93.7% (30/32) of tuberculin negative and 95.2% (40/42) of tuberculin positive healthy individuals had no detectable antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Evaluation of an enzyme immunoassay for the rapid diagnosis of paucibacillary tuberculosis in adults]. 251 43


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