Mycobacterium leprae replicates within mononuclear phagocytes, reaching enormous numbers in the macrophage-rich granulomas of lepromatous leprosy. To examine the capability of macrophages to digest M. leprae, we studied the intracellular fate of M. leprae organisms in normal and activated mouse macrophages by using the electron-dense secondary lysosome tracer Thoria Sol. Intracellular M. leprae...

A phenolic glycolipid was obtained in high amounts (2% of dry weight) from Mycobacterium leprae isolated from infected armadillo liver. Infrared and nuclear magnetic resonance spectroscopy showed that it is closely related to "mycoside A" from Mycobacterium kansasii and is therefore a glycosylphenolic phthiocerol diester. The crucial difference between the two products is in the composition of ...

Little is known of the direct microbicidal activity of T cells in leprosy, so a lipopeptide consisting of the N-terminal 13 amino acids lipopeptide (LipoK) of a 33-kD lipoprotein of Mycobacterium leprae, was synthesized. LipoK activated M. leprae infected human dendritic cells (DCs) to induce the production of IL-12. These activated DCs stimulated autologous CD4+ or CD8+ T cells towards type 1 ...

BACKGROUND Leprosy is a contagious and chronic systemic granulomatous disease caused by Mycobacterium leprae. In the pathogenesis of leprosy, granulomas play a key role, however, the mechanisms of the formation and maintenance of M. leprae granulomas are still not clearly understood. METHODS To better understand the molecular physiology of M. leprae granulomas and the interaction between the ...

The significance of Hansen disease, or leprosy, is underscored by fact that detection of this disease has remained stable over the past 10 yr, even though disease prevalence is reduced. Due to the long incubation time of the organism, health experts predict that leprosy will be with us for decades to come. Despite the fact that Mycobacterium leprae, the causative agent of leprosy, cannot be cul...

A panel of nine monoclonal antibodies to Mycobacterium leprae were used to characterize a protein antigen of the bacillus. Two monoclonal antibodies (IVD8 and IIIE9) were specific for M. leprae and reacted with an epitope (CWPa) present on a protein molecule associated with the cell wall fraction of M. leprae. This protein, designated cell wall-associated protein (CWP), lost its immunoreactivit...

The pathological changes, bacterial load, and viability of Mycobacterium leprae in the skin and nerves of nine lepromatous leprosy patients who had undergone 2 years of multidrug therapy (MDT) were studied. M. leprae and varying amounts of their remnants were present in the nerves and skin of all but one patient. M. leprae isolated from skin biopsies of six patients and nerve biopsies of nine p...

OBJECTIVE Establish a typing system for Mycobacterium leprae based on polymorphic DNA structures known as short tandem repeats (STR). DESIGN Assess 16 polymorphic STR for sensitivity, specificity and reproducibility in standard assays using reference strains of M. leprae. RESULTS Primers for 16 STR loci were selected based on PCR product size and for their ability to sequence each STR locus...

In this study, we compared the level of TNF-alpha secretion induced in monocytic THP-1 cells after phagocytosis of Mycobacterium leprae, the causative agent of leprosy, and M. bovis BCG, an attenuated strain used as a vaccine against leprosy and tuberculosis. The presence of M. leprae and BCG was observed in more than 80% of the cells after 24 h of exposure. However, BCG but not M. leprae was a...

Evidence is accumulating that Mycobacterium leprae is probably a microbe­ dependent microbe. l O1 3 The first report that multiplication of M. leprae was promoted by a growth factor of mycobacterial origin was proposed by Twort l 9 in 1 9 1 0 , two years before the discovery of the cultivation of 'lohne's bacilli' in media enriched with heat-killed mycobacteria . 2o The growth factor was identi...