S Afr Med J
September 2014
Adults presenting with recurrent infections require an approach that allows exclusion of underlying immunodeficiency. While secondary causes of immunodeficiency are the most common, primary immunodeficiency disease (PID) may present for the first time in adults. Failure to consider this diagnosis in adults and children leads to a major diagnostic delay.
View Article and Find Full Text PDFBackground: While vaccination at birth with Mycobacterium bovis Bacilli Calmette-Guérin (BCG) protects against severe childhood tuberculosis, there is no consensus as to which components of the BCG-induced immune response mediate this protection. However, granulysin and perforin, found in the granules of cytotoxic T lymphocytes and Natural Killer (NK) cells, can kill intracellular mycobacteria and are implicated in protection against Mycobacterium tuberculosis.
Methods: We compared the cellular expression of granulysin and perforin cytolytic molecules in cord blood and peripheral blood from 10-week-old infants vaccinated at birth with either Japanese or Danish BCG, administered either intradermally or percutaneously.
Background: Current treatment regimens for pulmonary tuberculosis require at least 6 months of therapy. Immune adjuvant therapy with recombinant interferon-gamma1b (rIFN-gammab) may reduce pulmonary inflammation and reduce the period of infectivity by promoting earlier sputum clearance.
Methodology/principal Findings: We performed a randomized, controlled clinical trial of directly observed therapy (DOTS) versus DOTS supplemented with nebulized or subcutaneously administered rIFN-gamma1b over 4 months to 89 patients with cavitary pulmonary tuberculosis.
Despite routine vaccination with Mycobacterium bovis bacillus Calmette-Guérin (BCG) soon after birth, tuberculosis in babies and adults remains epidemic in South Africa. The immune responses of the naïve newborn child and how they are affected by vaccination with BCG are as yet not fully understood. Immunity during pregnancy and in healthy human newborns may be skewed toward type 2 cytokine production; however, it is type 1 cytokines that are required for protection against M.
View Article and Find Full Text PDFTuberculosis (Edinb)
January 2008
The host response to Mycobacterium tuberculosis includes macrophage activation, inflammation with increased immune effector cells, tissue necrosis, and cavity formation, and fibrosis, distortion, and bronchiectasis. To evaluate the molecular basis of the immune response in the lungs of patients with active pulmonary tuberculosis (TB), we used bronchoalveolar lavage to obtain cells at the site of infection. Affymetrix GeneChip microarrays and cDNA nylon filter microarrays interrogated gene expression in bronchoalveolar lavage (BAL) cells from 11 healthy controls and 17 patients with active pulmonary TB.
View Article and Find Full Text PDFFactors that relate to medium-term outcome in patients with pulmonary tuberculosis (PTB) who have completed the 2-month intensive phase of treatment are incompletely understood. The relationship between in vitro production of interferon-gamma (IFN-gamma), interleukins (ILs)-5 and -10 and drug levels determined after 2 months of drug therapy, to outcome at 24 months was studied prospectively. Cytokine concentrations were determined from culture supernatants after stimulation of whole blood with purified protein derivative (PPD) of Mycobacterium tuberculosis.
View Article and Find Full Text PDFIn 10-week-old infants vaccinated at birth with Japanese Mycobacterium bovis BCG, the number of dermal needle penetrations correlated positively with frequency of proliferating CD4(+) T cells in whole blood following BCG stimulation for 6 days but did not correlate with secreted cytokine levels after 7 h or interferon CD4(+) T-cell frequency after 12 h of BCG stimulation.
View Article and Find Full Text PDFVaccination with Mycobacterium bovis bacille Calmette-Guerin (BCG) has variable efficacy in preventing tuberculosis. Both BCG strain and route of administration have been implicated in determining efficacy; however, these variables are not considered in current clinical recommendations for vaccine choice. We evaluated antigen-specific immunity after percutaneous or intradermal administration of Japanese BCG or intradermal administration of Danish BCG.
View Article and Find Full Text PDFMicrowave vacuum drying is getting more and more popular thanks to its known advantageous and unique features, but its non-uniform electric field can cause nonhomogeneous temperature distribution in the workload. The origin and effect of a generated hot-spot is influenced by the electromagnetic and thermodynamic features of the microwave system and the workload. In the case of single/one pot technology, the geometry and the construction of the microwave cavity is primarily designed for high-shear granulation.
View Article and Find Full Text PDFGenetic defects in the IFN-gamma response pathway cause unique susceptibility to intracellular pathogens, particularly mycobacteria, but are rare and do not explain mycobacterial disease in the majority of affected patients. We postulated that acquired defects in macrophage activation by IFN-gamma may cause a similar immunological phenotype and thus explain the occurrence of disseminated intracellular infections in some patients without identifiable immune deficiency. Macrophage activation in response to IFN-gamma and IFN-gamma production were studied in whole blood and PBMCs of 3 patients with severe, unexplained nontuberculous mycobacterial infection.
View Article and Find Full Text PDFMicrowave assisted vacuum drying offers never questioned advantageous and it is getting more and more popular lately. In spite of its uniqueness there is a rightful resistance and mistrust because the temperature distribution of the workload is far from being homogeneous as a result of the existing inhomogeneous electromagnetic field. The aim of this study is to survey the heat thus field distribution in the workload to prevent local overheating that endangers the quality of the pharmaceutical product.
View Article and Find Full Text PDFWe optimized a whole blood intracellular cytokine assay to quantitate the frequency of specific CD4+ and CD8+ T cells in small volumes of whole blood from infants from developing countries. The assay is performed in two steps. First, whole blood is stimulated in the presence of specific antigens for 6-18 h, ending with cryopreservation of fixed white cells.
View Article and Find Full Text PDFThis study evaluated whether different bacillus Calmette-Guérin (BCG) strains, routes of administration, vaccination age and percutaneous tools influenced immune responses to BCG vaccination in infants. Proliferative responses, cytokine production and cell-mediated cytotoxicity obtained in post-vaccinated children were compared to baseline cord bloods and unvaccinated 10-week-old infants. BCG vaccination generally induced strong lymphoproliferative and T helper type 1 (Th1)-type cytokine responses.
View Article and Find Full Text PDFOne of the most important effector functions of activated gammadelta+ T cells in tuberculosis is their strong cytolytic activity against a variety of target cells, including M. tuberculosis-infected macrophages. In the present study, we investigated the relationship between the mechanism of cytolysis utilized by gammadelta+ CTL and intracellular M.
View Article and Find Full Text PDFDespite strong evidence for CD8+ T-cell function in murine mycobacterial infections, their corresponding role in human tuberculosis has proven more difficult to demonstrate. We have evaluated the human macrophage (Mphi) cell line U937 as an in vitro model for human leucocyte antigen (HLA) class I-restricted presentation of mycobacterial antigens, as HLA class I is constitutively expressed at high levels by U937 cells in the absence of detectable HLA class II or CD1 molecules. U937 cells were evaluated for their ability to phagocytose Mycobacterium tuberculosis and for their ability to present mycobacterial antigens to human HLA class I-matched cytotoxic T lymphocytes (CTLs).
View Article and Find Full Text PDFProteins which are secreted or associated with the cell envelope of Mycobacterium tuberculosis may contain protective T-cell epitopes. Prior to this study, a recombinant clone bank of enzymatically active M. tuberculosis-alkaline phosphatase fusions, were screened for immunogenicity in a murine T-cell model.
View Article and Find Full Text PDFNovartis Found Symp
March 1999
Multidrug-resistant tuberculosis patients respond poorly to antituberculosis therapy and therefore require new modalities of treatment to overcome the infection. Administration of low dose recombinant human interleukin 2 (rhuIL-2) in combination with chemotherapy to multidrug-resistant tuberculosis patients resulted in reduced or cleared sputum acid-fast bacilli in about 60% of the patients in association with enhanced activation of the immune system. Daily rhuIL-2 administration for 30 days induced increases in CD25+ and CD56+ cells in the blood.
View Article and Find Full Text PDFAdministration of low-dose recombinant human interleukin 2 (rhuIL-2) in combination with multidrug chemotherapy to patients with multidrug-resistant tuberculosis (MDR TB) induces measurable changes in in vitro immune response parameters which are associated with changes in the clinical and bacteriologic status of the patients. To determine the molecular basis of these changes, we have used semiquantitative reverse transcriptase-initiated PCR (RT-PCR) and differential display technology. During rhuIL-2 treatment of MDR TB patients, decreased levels of gamma interferon (IFN-gamma) mRNA in peripheral blood mononuclear cells (PBMC) relative to baseline levels were observed.
View Article and Find Full Text PDFMononuclear leucocytes from the blood (PBML) and effusion (EML) of patients undergoing pericardiocentesis were assayed for proliferative response to purified protein derivative of Mycobacterium tuberculosis (PPD). Of the 23 patients tested, 10 had culture-positive tuberculous effusions, while 13 had non-tuberculous aetiologies. Three different kinetic responses were identified: (i) accelerated responses (found in 70% of EML from patients with culture-positive tuberculous effusions); (ii) 'flat' responses (found in 10% of EML from patients with culture-positive tuberculous effusions); and (iii) normal kinetic responses.
View Article and Find Full Text PDFSetting: Low-dose recombinant human interleukin 2 (rhuIL-2) adjunctive immunotherapy in multidrug resistant tuberculosis (MDR-TB) patients.
Objective: Evaluation of the effects of daily versus pulse-administered rhuIL-2 compared to placebo.
Design: MDR-TB patients on best available antituberculous chemotherapy received rhuIL-2 for 30 consecutive days (daily therapy), or for 5 days followed by a 9-day 'rest', for three cycles (pulse therapy).
Accelerated PPD-specific proliferation and generation of CD4+ cytotoxic effectors by mononuclear leucocytes (MNL) from tuberculous effusions (EMNL) has been previously reported by our laboratory. In order to explore the contribution of the state of activation of MNL to accelerated reactivity, EMNL and peripheral blood (PB)MNL from seven patients with tuberculosis were assessed both ex vivo and after PPD stimulation. Flow cytometry revealed no difference in the activation state (IL-2 receptor and HLA-DR expression) or cell cycle progression ex vivo.
View Article and Find Full Text PDFCytokines Mol Ther
September 1995
The immune response to infection with M. tuberculosis depends on cytokine activation of effector cells. We therefore conducted a pilot study of recombinant human interleukin-2 (rhuIL-2) as an adjunct to multidrug therapy (MDT) to evaluate the safety of this approach and to determine whether IL-2 can enhance the cellular immune response in patients with pulmonary tuberculosis (TB).
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