[Prospects for leprosy treatment via complexation of rifampicin witH iodide and horse-radish root].

A model of leprosy was used to study the therapeutic effect of horse-radish root (HRR) containing peroxidase in combination with rifampicin (RFP) and potassium iodide (PI) as compared to routine combined therapy with RFP and diaminodiphenylsulfonum. Therapy with HRR and iodide showed the best antimicrobial effect than the routine combined therapy. A combination of RFP, HRR, and PI increased the activity of neutrophilic myeliperoxidase produced an anti-inflammatory activity and caused no persistent anemia or toxic effect on the murine liver.

Modulation of the catalytic activity of neutrophil collagenase MMP-8 on bovine collagen I. Role of the activation cleavage and of the hemopexin-like domain.

The cleavage of bovine collagen I by neutrophil collagenase MMP-8 has been followed at pH 7.4, 37 degrees C. The behavior of the whole enzyme molecule (whMMP-8), displaying both the catalytic domain and the hemopexin-like domain, has been compared under the same experimental conditions with that of the catalytic domain only. The main observation is that whMMP-8 cleaves bovine collagen I only at a single specific site, as already reported by many others (Mallya, S. K., Mookhtiar, K. A., Gao, Y., Brew, K., Dioszegi, M., Birkedal-Hansen, H., and van Wart, H. E. (1990) Biochemistry 29, 10628-10634; Knäuper, V., Osthues, A., DeClerk, Y. A., Langley, K. A., Bläser, J., and Tschesche, H. (1993) Biochem. J. 291, 847-854; Marini, S., Fasciglione, G. F., De Sanctis, G., D'Alessio, S., Politi, V., and Coletta, M. (2000) J. Biol. Chem. 275, 18657-18663), whereas the catalytic domain lacks this specificity and cleaves the collagen molecule at multiple sites. Furthermore, a meaningful difference is observed for the cleavage features displayed by two forms of the catalytic domain, which differ for the N terminus resulting from the activation process (i.e. the former Met(80) of the proenzyme (MetMMP-8) and the former Phe(79) of the proenzyme (PheMMP-8)). Thus, the PheMMP-8 species is characterized by a much faster k(cat)/K(m), fully attributable to a lower K(m), suggesting that the conformation of the catalytic domain, induced by the insertion of this N-terminal residue in a specific pocket (Reinemer, P., Grams, F., Huber, R., Kleine, T., Schnierer, S., Piper, M., Tschesche, H., and Bode, W. (1994) FEBS Lett. 338, 227-233), brings about a better, although less discriminatory, recognition process of cleavage site(s) on bovine collagen I.

Activation of human neutrophils by mycobacterial phenolic glycolipids.

The interaction between mycobacterial phenolic glycolipids (PGLs) and phagocytes was studied. Human neutrophils were allowed to interact with each of four purified mycobacterial PGLs and the neutrophil production of reactive oxygen metabolites was followed kinetically by luminol-/isoluminol-amplified chemiluminescence. The PGLs from Mycobacterium tuberculosis and Mycobacterium kansasii, respectively, were shown to stimulate the production of oxygen metabolites, while PGLs from Mycobacterium marinum and Mycobacterium bovis BCG, respectively, were unable to induce an oxidative response. Periodate treatment of the M. tuberculosis PGL decreased the production of oxygen radicals, showing the importance of the PGL carbohydrate moiety for the interaction. The activation, however, could not be inhibited by rhamnose or fucose, indicating a complex interaction which probably involves more than one saccharide unit. This is in line with the fact that the activating PGLs from M. tuberculosis and M. kansasii contain tri- and tetrasaccharides, respectively, while the nonactivating PGLs from M. marinum and M. bovis BCG each contain a monosaccharide. The complement receptor 3 (CR3) has earlier been shown to be of importance for the phagocyte binding of mycobacteria, but did not appear to be involved in the activation of neutrophils by PGLs. The subcellular localization of the reactive oxygen metabolites formed was related to the way in which the glycolipids were presented to the cells.

Leucocytic alkaline phosphatase activity in leprosy: a possible guide in the follow-up of leprosy.

In order to investigate a possible involvement of phagocytic cells in the various types of leprosy, we undertook the study of enzymatic activities in circulating leucocytes. The activity of leucocytic alkaline phosphatase was studied by histochemical techniques on blood smears in 31 patients presenting with leprosy and aged between 4 and 73, and in 11 non infected people. The 31 patients suffering from leprosy were distributed as following: 14 lepromatous leprosy of which 6 had not yet been treated and 8 were under treatment, 9 cases of tuberculoid leprosy of which 7 had been treated and 2 had not yet, 3 cases of borderline leprosy which had all been treated, and 5 patients whose form of leprosy was indeterminate (before treatment). The distribution of the different values we obtain shows a very significant difference (p less than 0.001) between patients with and without leprosy (respectively 33.8 +/- 7.3 and 109.8 +/- 12.5). Moreover, the decrease of the alkaline phosphatase activity correlated with the severity of the disease (47.2 +/- 11.4 in tuberculoid leprosy and 20.6 +/- 9.3 in lepromatous leprosy) thus suggesting that the evaluation of leucocytic alkaline phosphatase activity should be advised as a possible prognosis guide in indeterminate leprosy.

Lysozyme as a measure of cellular dynamics in the lesions of leprosy.

The levels and distribution of lysozyme-positive cells and exudate were studied in leprosy lesions through the spectrum, in untreated and treated patients, in relapse and in reactions. Altogether 124 skin biopsies were examined by the immunoperoxidase technique. Monocytes, neutrophil-polymorphs and mast cells were the most conspicuous cells seen. Lysozyme proved to be a useful means of indexing renewal of these cells in the lesions. Peak numbers of monocytes were seen in lesions of active lepromatous leprosy (LL) and of tuberculoid leprosy (TT), at poles of opposite immunological performance. In TT the stimulus for recruitment was delayed hypersensitivity (DH). A decline in DH from TT towards the middle of the spectrum, mid-borderline, was accompanied by a fall in monocyte level. Furthermore, reacting lesions due to enhanced DH also had increased numbers of monocytes. On the other hand reactions associated with immunological deterioration were similar to active lepromatous leprosy (LL) and monocyte influx was raised in response to the stimulus of free multiplication of bacilli in both cases. In TT delayed hypersensitivity acted also to promote the rapid transformation of monocytes to epithelioid and giant cells all of which were strongly positive for lysozyme. This was in contrast to much lower levels in histologically similar macrophage-epithelioid cells of BT granulomas. Lysozyme synthesis was not seen in macrophages after ingestion of M. leprae. Early foamy change was made conspicuous by lysozyme deposited in phagocytic vacuoles, but old foam cells in regressing lepromas were negative. Lysozyme bound to dead extracellular M. leprae but not to viable or intracellular organisms. Dead bacilli or immune complexes appeared to be the stimulus for neutrophil-polymorph recruitment, mainly in reactions.

In vitro effect of Mycobacterium leprae suspensions on the polymorphonuclear neutrophiles function of hanseníasis patients to Candida albicans and Candida pseudotropicalis

The in vitro effect of Mycobacterium leprae suspensions on the PMN hability to phagocyting and killing Candida albicans and Candida pseudotropicalis was studied in forty-five patients of Hansen's disease and in fifteen healthy controls. Our results show no significative differences between the diferent studied groups, both for the phagocytosis and for the lysis of yeasts. There was no significant changes in the mean values of these functions after previous or simultaneously incubation with Mycobacterium leprae suspensions. Those observations confirmed that there are not alterations in the enzimatic battery of PMN in Hansen's disease patients and that the Mycobacterium leprae presence does not exert stimulating effect on this in vitro model