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Jerrold J Ellner

Publications and source records attributed to Jerrold J Ellner.

At least 19 recordsLinked to original sources
PubMed2007

Low-cost rapid detection of rifampicin resistant tuberculosis using bacteriophage in Kampala, Uganda.

BACKGROUND: Resistance to anti-tuberculosis drugs is a serious public health problem. Multi-drug resistant tuberculosis (MDR-TB), defined as resistance to at least rifampicin and isoniazid, has been reported in all regions of the world. Current phenotypic methods of assessing drug susceptibility of M. tuberculosis are slow. Rapid molecular methods to detect resistance to rifampicin have been developed but they are not affordable in some high prevalence countries such as those in sub Saharan Africa. A simple multi-well plate assay using mycobacteriophage D29 has been developed to test M. tuberculosis isolates for resistance to rifampicin. The purpose of this study was to investigate the performance of this technology in Kampala, Uganda. METHODS: In a blinded study 149 M. tuberculosis isolates were tested for resistance to rifampicin by the phage assay and results compared to those from routine phenotypic testing in BACTEC 460. Three concentrations of drug were used 2, 4 and 10 microg/ml. Isolates found resistant by either assay were subjected to sequence analysis of a 81 bp fragment of the rpoB gene to identify mutations predictive of resistance. Four isolates with discrepant phage and BACTEC results were tested in a second phenotypic assay to determine minimal inhibitory concentrations. RESULTS: Initial analysis suggested a sensitivity and specificity of 100% and 96.5% respectively for the phage assay used at 4 and 10 microg/ml when compared to the BACTEC 460. However, further analysis revealed 4 false negative results from the BACTEC 460 and the phage assay proved the more sensitive and specific of the two tests. Of the 39 isolates found resistant by the phage assay 38 (97.4%) were found to have mutations predictive of resistance in the 81 bp region of the rpoB gene. When used at 2 mug/ml false resistant results were observed from the phage assay. The cost of reagents for testing each isolate was estimated to be 1.3 US dollars when testing a batch of 20 isolates on a single 96 well plate. Results were obtained in 48 hours. CONCLUSION: The phage assay can be used for screening of isolates for resistance to rifampicin, with high sensitivity and specificity in Uganda. The test may be useful in poorly resourced laboratories as a rapid screen to differentiate between rifampicin susceptible and potential MDR-TB cases.

Antibiotics, Antitubercular↗
PubMed2006

Delayed-type hypersensitivity skin test reactivity and survival in HIV-infected patients in Uganda: should anergy be a criterion to start antiretroviral therapy in low-income countries?

Access to antiretroviral (ARV) drugs is improving in sub-Saharan Africa but still constrained by several clinical and logistical obstacles. There is a need to develop affordable markers to guide initiation of treatment. We present a prospective cohort study of 779 patients participating in a TB prophylaxis trial. We performed separate analyses for anergic and nonanergic subjects. Prognostic factors for anergic and nonanergic subjects differed between groups. Individuals with anergy and constitutional symptoms were at the highest risk of death. Incident tuberculosis and CD4 < 200 cells/muL at enrollment were the strongest risk factors for death. HIV disease is associated with substantial morbidity and mortality in this population. The burden caused by tuberculosis is particularly high. Anergy is a strong and independent predictor of death. World Health Organization criteria to start ARV may be strengthened with the addition of DTH testing, an inexpensive and readily available tool in sub-Saharan Africa.

Adolescent↗
PubMed2005

Mycobacterium tuberculosis growth control by lung macrophages and CD8 cells from patient contacts.

RATIONALE: Healthy household contacts (HHCs) of patients with active pulmonary tuberculosis are exposed aerogenically to Mycobacterium tuberculosis (Mtb), thus permitting the study of protective local immunity. OBJECTIVES: To assess alveolar macrophage (AM) and autologous blood CD4 and CD8 T-cell-mediated Mtb growth control in HHCs and healthy, unexposed community control subjects (CCs). METHODS: AMs were infected with Mtb strains H(37)Ra and H(37)Rv at multiplicities of infection 0.1 and 1. Mtb colony-forming units were evaluated on Days 1, 4, and 7. MAIN RESULTS: CD8 T cells from HHCs in 1:1 cocultures with AMs significantly (p < 0.05) increased Mtb growth control by AMs. In CCs, no detectable contribution of CD8 T cells to Mtb growth control was observed. CD4 T cells did not increase Mtb growth control in HHCs or in CCs. IFN-gamma, nitric oxide, and tumor necrosis factor were determined as potential mediators of Mtb growth control in AMs and AM/CD8 and AM/CD4 cocultures. IFN-gamma production in AM/CD4 was twofold higher than that in AM/CD8 cocultures in both HHCs and CCs (p < 0.05). Nitric oxide production from AMs of HHCs increased on Days 4 and 7 and was undetectable in AMs from CCs. IFN-gamma and nitric acid concentrations and Mtb growth control were not correlated. Tumor necrosis factor levels were significantly increased in AM/CD8 cocultures from HHCs compared with AM/CD8 cocultures from CCs (p < 0.05). CONCLUSION: Aerogenic exposure to Mtb in HHCs leads to expansion of Mtb-specific effector CD8 T cells that limit Mtb growth in autologous AMs.

Adolescent↗
PubMed2005

Immunoadjuvant prednisolone therapy for HIV-associated tuberculosis: a phase 2 clinical trial in Uganda.

Background. Human immunodeficiency virus (HIV)-infected patients with tuberculosis (TB) respond to effective antituberculous therapy, but their prognosis remains poor. Mounting evidence from clinical studies supports the concept of copathogenesis in which immune activation that is triggered by TB and mediated by cytokines stimulates viral replication and worsens HIV infection, especially when immune function is preserved.Methods. We performed a phase 2, randomized, double-blind, placebo-controlled clinical trial in Kampala, Uganda, to determine whether immunoadjuvant prednisolone therapy in HIV-infected patients with TB who have CD4(+) T cell counts >/=200 cells/ mu L is safe and effective at increasing CD4(+) T cell counts.Results. Short-term prednisolone therapy reduced levels of immune activation and tended to produce higher CD4(+) T cell counts. Although prednisolone therapy was associated with a more rapid clearance of Mycobacterium tuberculosis from the sputum, it was also associated with a transient increase in HIV RNA levels, which receded when prednisolone therapy was discontinued. The intervention worsened underlying hypertension and caused fluid retention and hyperglycemia.Conclusion. The benefits of prednisolone therapy on immune activation and CD4(+) T cell counts do not outweigh the risks of adverse events in HIV-infected patients with TB and preserved immune function.

AIDS-Related Opportunistic Infections↗
PubMed2005

Mechanisms of apoptosis of T-cells in human tuberculosis.

The role of TGF-beta TNF-alpha FasL and Bcl-2 in apoptosis of CD4 T-cells during active TB was studied. Coculture of PBMC from TB patients with neutralizing antibodies to TGF-beta or TNF-alpha decreased spontaneous (P < or = 0.05) and MTB-induced (P < or = 0.02) T-cell apoptosis by 50-90%, but effects were not additive. Interestingly, only levels of TGF-beta in supernatants correlated with rates of spontaneous and MTB-induced apoptosis. FasL surface and mRNA expression were higher in unstimulated and MTB-stimulated PBMC from patients than controls, and neutralization of FasL abrogated apoptosis of T-cells from patients only. Intracellular Bcl-2 protein was lower among unstimulated CD4 T-cells from patients than those from controls (P < or = 0.02), and MTB stimulation reduced intracellular Bcl-2 content in CD4 T-cells from patients only (P < or = 0.001). These findings may indicate that, during TB, predisposition of CD4 T-cells to apoptosis may involve both low expression of Bcl-2, and excessive expression of TGF-beta TNF-alpha and FasL.

Adolescent↗
PubMed2005

Human {beta}-defensin 2 is expressed and associated with Mycobacterium tuberculosis during infection of human alveolar epithelial cells.

To determine the role of human beta-defensin 2 (HBD-2) in human tuberculosis, we studied the in vitro induction of HBD-2 gene expression by Mycobacterium tuberculosis H37Rv infection in the human lung epithelial cell line A549, in alveolar macrophages (AM), and in blood monocytes (MN) by reverse transcription-PCR. We also studied the induction of HBD-2 gene expression by mannose lipoarabinomannan (manLAM) from M. tuberculosis. Intracellular production of HBD-2 peptide was detected by immunocytochemistry and electron microscopy. Our results demonstrated that there was induction of HBD-2 mRNA in A549 cells after infection with M. tuberculosis at various multiplicities of infection (MOI) and that there was stimulation with manLAM. AM expressed the HBD-2 gene only at a high MOI with M. tuberculosis. MN did not express HBD-2 at any of the experimental M. tuberculosis MOI. Immunostaining revealed the presence of intracellular HBD-2 peptide in A549 cells following infection with M. tuberculosis, and the staining was more intense in areas where there were M. tuberculosis clusters. By using electron microscopy we also demonstrated production of HBD-2 after M. tuberculosis infection and adherence of HBD-2 to the membranes of M. tuberculosis. Alveolar epithelial cells are among the first cells to encounter M. tuberculosis following aerogenic infection. As HBD-2 has been shown to control growth of M. tuberculosis and has chemotactic activity, our results suggest that HBD-2 induction by M. tuberculosis may have a role in the pathogenesis of human tuberculosis.

Gene Expression Regulation↗
PubMed2004

A randomized, double-blind, placebo-controlled trial of the use of prednisolone as an adjunct to treatment in HIV-1-associated pleural tuberculosis.

BACKGROUND: Active tuberculosis may accelerate progression of human immunodeficiency virus (HIV) infection by promoting viral replication in activated lymphocytes. Glucocorticoids are used in pleural tuberculosis to reduce inflammation-induced pathology, and their use also might reduce progression of HIV by suppressing immune activation. We examined the effect that prednisolone has on survival in HIV-1-associated pleural tuberculosis. METHODS: We conducted a randomized, double-blind, placebo-controlled trial of prednisolone as an adjunct to tuberculosis treatment, in adults with HIV-1-associated pleural tuberculosis. The primary outcome was death. Analysis was by intention to treat. RESULTS: Of 197 participants, 99 were assigned to the prednisolone group and 98 to the placebo group. The mortality rate was 21 deaths/100 person-years (pyr) in the prednisolone group and 25 deaths/100 pyr in the placebo group (age-, sex-, and initial CD4+ T cell count-adjusted mortality rate ratio, 0.99 [95% confidence interval, 0.62-1.56] [P =.95]). Resolution of tuberculosis was faster in the prednisolone group, but recurrence rates were slightly (though not significantly) higher, and use of prednisolone was associated with a significantly higher incidence of Kaposi sarcoma (4.2 cases/100 pyr, compared with 0 cases/100 pyr [P =.02]). CONCLUSIONS: In view of the lack of survival benefit and the increased risk of Kaposi sarcoma, the use of prednisolone in HIV-associated tuberculous pleurisy is not recommended.

AIDS-Related Opportunistic Infections↗
PubMed2004

Airborne infection with Bacillus anthracis--from mills to mail.

The lack of identified exposures in 2 of the 11 cases of bioterrorism-related inhalation anthrax in 2001 raised uncertainty about the infectious dose and transmission of Bacillus anthracis. We used the Wells-Riley mathematical model of airborne infection to estimate 1) the exposure concentrations in postal facilities where cases of inhalation anthrax occurred and 2) the risk for infection in various hypothetical scenarios of exposure to B. anthracis aerosolized from contaminated mail in residential settings. These models suggest that a small number of cases of inhalation anthrax can be expected when large numbers of persons are exposed to low concentrations of B. anthracis. The risk for inhalation anthrax is determined not only by bacillary virulence factors but also by infectious aerosol production and removal rates and by host factors.

Air Microbiology↗
PubMed2003

Randomized trial of adjunctive interleukin-2 in adults with pulmonary tuberculosis.

Interleukin (IL)-2 has a central role in regulating T cell responses to Mycobacterium tuberculosis. Adjunctive immunotherapy with recombinant human IL-2 was studied in a randomized, placebo-controlled, double-blinded trial in 110 human immunodeficiency virus-seronegative adults in whom smear-positive, drug-susceptible pulmonary tuberculosis was newly diagnosed. Patients were randomly assigned to receive twice-daily injections of 225, 000 IU of IL-2 or placebo for the first 30 days of treatment in addition to standard chemotherapy. Subjects were followed for 1 year. The primary endpoint was the proportion of patients with sputum culture conversion after 1 and 2 months of treatment. After 1 month, the proportion of patients for whom sputum culture converted to negative was 17% for the IL-2 group compared with 30% in the control group (p = 0.14; chi2). After 2 months, 77% in the IL-2 group were culture negative compared with 85% of those receiving placebo (p = 0.29, chi2). Results were similar when patients with isoniazid monoresistance were included in the analysis. There were no differences in weight gain and no improvement in fever, cough, and chest pain between groups. One patient in each arm relapsed. IL-2 did not enhance bacillary clearance or improvement in symptoms in human immunodeficiency virus-seronegative adults with drug-susceptible tuberculosis.

Adult↗
PubMed2003

Whole blood bactericidal activity during treatment of pulmonary tuberculosis.

The timely evaluation of new drugs that can be used to shorten tuberculosis (TB) treatment will require surrogate markers for relapse. This study examined bactericidal activity against intracellular Mycobacterium tuberculosis in whole blood culture (whole blood bactericidal activity; WBA) during TB treatment. In the absence of chemotherapy, immune mechanisms in patient blood resulted in bacteriostasis, whereas administration of oral chemotherapy resulted in bacillary killing. Total WBA per dose was greater during the intensive phase of treatment than during the continuation phase (mean, -2.32 vs. -1.67 log(10) cfu-days, respectively; P<.001). Cumulative WBA throughout treatment was greater in subjects whose sputum cultures converted to negative by the eighth week of treatment than in those for whom conversion was delayed (mean, -365 vs. -250 log(10) cfu-days; P=.04) and correlated with the rate of decrease of sputum colony-forming unit counts during the first 4 weeks of treatment (P=.018), both of which are indicative of prognosis. These findings indicate that measurement of WBA may have a role in assessing the sterilizing activity of new anti-TB drugs.

Adolescent↗
PubMed2002

Investigation of the relationships between immune-mediated inhibition of mycobacterial growth and other potential surrogate markers of protective Mycobacterium tuberculosis immunity.

Tuberculosis (TB) vaccine development is hindered by the lack of clear surrogate markers of protective human immunity to Mycobacterium tuberculosis. This study evaluated the hypothesis that immune-mediated inhibition of mycobacterial growth would more directly correlate with protective TB immunity than other immunologic responses. Bacille Calmette-Guérin (BCG) vaccination, known to induce partial protection against TB, was used as a model system to investigate mechanistic relationships among different parameters of antigen-specific immunity. Effects of primary and booster intradermal BCG vaccinations were assessed in 3 distinct assays of mycobacterial inhibition. Correlations between vaccine-induced growth inhibition and other immune responses were analyzed. BCG significantly enhanced all antigen-specific responses. Peak responses occurred at 2 months after boosting. Statistical analyses suggested that each assay measured unique aspects of mycobacterial immunity. Despite previous evidence that type 1 immune responses are essential for TB immunity, interferon-gamma production did not correlate with mycobacterial inhibition. These results have important implications for TB vaccine development.

BCG Vaccine↗
PubMed2002

Gender and HIV-associated pulmonary tuberculosis: presentation and outcome at one year after beginning antituberculosis treatment in Uganda.

BACKGROUND: Tuberculosis is responsible for more female deaths around the earth than any other infectious disease. Reports have suggested that responses to tuberculosis may differ between men and women. We investigated gender related differences in the presentation and one year outcomes of HIV-infected adults with initial episodes of pulmonary tuberculosis in Uganda. METHODS: We enrolled and followed up a cohort of 105 male and 109 female HIV-infected adults on treatment for initial episodes of culture-confirmed pulmonary tuberculosis between March 1993 and March 1995. A favorable outcome was defined as being cured and alive at one year while an unfavorable outcome was not being cured or dead. Subjects were followed-up by serial medical examinations, complete blood counts, serum beta2 microglobulin, CD4+ cell counts, sputum examinations, and chest x-rays. RESULTS: Male patients were older, had higher body mass indices, and lower serum beta2 microglobulin levels than female patients at presentation. At one year, there was no difference between male and female patients in the likelihood of experiencing a favorable outcome (RR 1.02, 95% CI 0.89-1.17). This effect persisted after controlling for symptoms, serum beta2 microglobulin, CD4+ cell count, and severity of disease on chest x-ray (OR 1.07, 95% CI 0.54-2.13) with a repeated measures model. CONCLUSIONS: While differences existed between males and females with HIV-associated pulmonary tuberculosis at presentation, the outcomes at one year after the initiation of tuberculosis treatment were similar in Uganda. Women in areas with a high HIV and tuberculosis prevalence should be encouraged to present for screening at the first sign of tuberculosis symptoms.

Journal Article↗
PubMed2002

Sputum cytokine levels in patients with pulmonary tuberculosis as early markers of mycobacterial clearance.

Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-gamma) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-gamma levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-gamma levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-gamma immunoreactivities in serum followed kinetics in sputum. TNF-alpha, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-gamma, however, TNF-alpha and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy.

Adolescent↗
PubMed2002

Bactericidal activity in whole blood as a potential surrogate marker of immunity after vaccination against tuberculosis.

The development of new tuberculosis (TB) vaccines will require the identification of correlates of human protection. This study examined the balance between immunity and virulence in a whole blood infection model in which intracellular mycobacterial survival was measured using BACTEC. In the blood of tuberculin-negative donors, counts of Mycobacterium tuberculosis H(37)Ra organisms fell by 0.14 log(10) CFU during 96 h of whole blood culture, whereas counts of Mycobacterium bovis BCG, M. tuberculosis H(37)Rv, and a clinical TB isolate's organisms increased by 0.13, 0.43, and 1.04 log(10) CFU, respectively (P < 0.001), consistent with their relative virulence. Inhibition of tumor necrosis factor alpha by the addition of methylprednisolone or pentoxifylline or removal of CD4(+) or CD8(+) T cells by magnetic beads had deleterious effects on immune control of intracellular growth only in the blood of tuberculin-positive donors. Repeated vaccination of eight tuberculin-negative volunteers with M. bovis BCG resulted in a 0.3 log (50%) reduction in BCG CFU counts in the model compared to baseline values (P < 0.05). Three of the volunteers responded only after the second vaccination. These experiments indicate that whole blood culture may be used to measure immunity to M. tuberculosis and that further studies of repeated BCG vaccination are warranted.

Adult↗