Mycobacterium leprae are killed by myeloperoxidase (or eosinophil peroxidase), H2O2, and a halide, thus suggesting a mechanism for their destruction by peroxidase-containing phagocytes.

The immune response of mice to live, heat-killed, or autoclaved Mycobacterium leprae was investigated. After sensitization with 10(7) organisms in each group, recipient mice were transfused with the sensitized splenocytes 28 days later. A selected number of these mice were infected with 5 X 10(3) M. leprae, and the remaining animals were sacrificed at scheduled intervals for evidence of cell-me...

The genes for dihydropteroate synthase of Mycobacterium tuberculosis and Mycobacterium leprae were isolated by hybridization with probes amplified from the genomic DNA libraries. DNA sequencing revealed an open reading frame of 840 bp encoding a protein of 280 amino acids for M. tuberculosis dihydropteroate synthase and an open reading frame of 852 bp encoding a protein of 284 amino acids for M...

Mycobacterium lepromatosis is an uncultured human pathogen associated with diffuse lepromatous leprosy and a reactional state known as Lucio's phenomenon. By using deep sequencing with and without DNA enrichment, we obtained the near-complete genome sequence of M. lepromatosis present in a skin biopsy from a Mexican patient, and compared it with that of Mycobacterium leprae, which has undergone...

Guinea pigs immunized with intact or disrupted armadillo-grown human Mycobacterium leprae administered in aqueous or oil vehicles were tested with various dilutions of M. leprae suspended in saline, water-soluble M. leprae extract, purified protein derivative, and a water-soluble extract of normal armadillo tissue. The results demonstrated the following. (i) Under no conditions was any skin tes...

Mycobacterium leprae is an intracellular pathogen that is ingested by and proliferates within cells of the monocyte/macrophage series. Mechanisms by which intracellular pathogens resist destruction may involve failure to elicit a phagocyte "respiratory burst" or resistance to toxic oxygen derivatives and lysosomal enzymes. We have studied the ability of M. leprae and Mycobacterium bovis BCG to ...

We reported earlier the occurrence of a unique o-diphenoloxidase in Mycobacterium leprae recovered from lepromatous human tissues. No other source of M. leprae fro biochemical studies was available at the time. In the present report, properties of phenoloxidase in M. leprae separated from infected armadillo tissues are presented. The results show that the o-diphenoloxidase remains unaltered in ...

Leprosy, which is caused by Mycobacterium leprae (M. leprae) (see Chapter 5.1), is primarily a disease of peripheral nerves. It is the only mycobacterial disease affecting the peripheral nerves, which are otherwise highly resistant to bacterial invasion. The target of nerve invasion by M. leprae is the Schwann cell. Man is the natural host of this infection, but a similar illness is found in th...

Previously, pefloxacin and ofloxacin were found to be active against Mycobacterium leprae in vitro, in experimental animals, and in clinical trials of lepromatous leprosy patients. In this study, we compared certain more recently developed fluoroquinolones (lomefloxacin, PD 124816, WIN 57273, temafloxacin, and sparfloxacin) with pefloxacin and ofloxacin in M. leprae-infected mice at doses of 50...

Cellular immunity mediated by T cells plays a major role in protection against intracellular infections, including leprosy, a chronic disease caused by Mycobacterium leprae. In this work, we describe CD4+ T-cell clones, isolated from healthy humans immunized with M. leprae, which recognize a novel M. leprae protein antigen previously isolated from a lambda gt11 DNA expression library. On the ba...