Macrophage nitric oxide synthase (NOS) activation by Nocardia opaca fractions and 15- and 56-kD isolated antigens

Abstract

SUMMARYThe Gram-positive bacterium, Nocardia opaca, is a source of substances with adjuvant effect, ability to stimulate macrophages and natural killer cells for enhanced cytotoxity and cytokine production and B lymphocytes for polyclonal immunoglobulin secretion. We determined the immunogenicity of isolated N. opaca fractions and prepared MoAbs against immunogenic water-soluble mitogen (NWSM). Two main proteins of molecular mass 15 and 56 kD were detected in Western blot analysis and isolated by affinity chromatography using anti-NWSM MoAb B7/7. Both these isolated nocardial antigens were found to stimulate mouse peritoneal macrophage NOS. The effect of 5 ¹ g NWSM was comparable to that of 5 ¹ g lipopolysaccharide (LPS) or 20 U of interferon-gamma (IFN-°) added to cell cultures. The MoAb B7/7 decreased NO 2 ÿ production induced by NWSM or by isolated nocardial antigens, but did not significantly influence the production elicited by LPS or IFN-°. On the other hand, NOS activation by NWSM was not affected by anti-IFN-°MoAb. The possible independent pathway for IFN-°and NWSM macrophage activation is discussed.

The Neurocognitive Outcome of Nocardia: A Brief, Longitudinal Case Study

“…Because of the nature and presence of the Nocardia bacteria, research has been performed to elucidate a correlation between certain neurocognitive disorders and infection. For example, Nocardia spp., a Nocardia bacteria subtype, has been linked to accumulation of nitric oxide-leading to apoptotic cell death, specifically in dopaminergic regions-suggesting a possible correlation between Parkinsonian movement symptoms and N. asteroides infection (Le et al, 2001;Tuckova, Zidek, Hanikyrova, Cukrowska, & Hogenova, 1996). Further research is warranted in this regard to establish other related correlations.…”