Interferon-alphacon-1 treatment of three patients with severe glucocorticoid-dependent asthma. Effect on disease control and systemic glucocorticosteroid dose.

We report herein the therapeutic effect of interferon (IFN)-alphacon in three patients with severe persistent asthma and long-term oral glucocorticoid treatment. IFN-alphacon (9 microg) administered subcutaneously thrice a week over a period of more than 24 months led to a substantial clinical improvement with regard to the number of daily asthma attacks, nighttime disturbance, emergency visits and hospitalizations. In addition, lung function and exercise capacity improved. At the same time, treatment with IFN allowed discontinuation of the daily glucocorticoid dose in all patients for the first time in more than 8 years. Our findings suggest that IFN-alphacon leads to a significant clinical improvement while at the same time allowing reduction and discontinuation of the glucocorticoid treatment in severe persistent glucocorticoid-dependent asthma.

Reactive nitrogen intermediates in giant cell arteritis: selective nitration of neocapillaries.

Arterial wall damage in giant cell arteritis (GCA) is mediated by several different macrophage effector functions, including the production of metalloproteinases and lipid peroxidation. Tissue-invading macrophages also express nitric oxide synthase (NOS)-2, but it is not known whether nitric oxide-related mechanisms contribute to the disease process. Nitric oxide can form nitrating agents, including peroxynitrite, a nitric oxide congener formed in the presence of reactive oxygen intermediates. Protein nitration selectively targets tyrosine residues and can result in a gain, as well as a loss, of protein function. Nitrated tyrosine residues in GCA arteries were detected almost exclusively on endothelial cells of newly formed microcapillaries in the media, whereas microvessels in the adventitia and the intima were spared. Nitration correlated with endothelial NOS-3 expression and not with NOS-2-producing macrophages, which preferentially homed to the hyperplastic intima. The restriction of nitration to the media coincided with the production of reactive oxygen intermediates as demonstrated by the presence of the toxic aldehyde, 4-hydroxynonenal. Depletion of tissue-infiltrating macrophages in human temporal artery-SCID mouse chimeras disrupted nitrotyrosine generation, demonstrating a critical role of macrophages in the nitration process that targeted medial microvessels. Thus, protein nitration in GCA is highly compartmentalized, reflecting the production of reactive oxygen and reactive nitrogen intermediates in the inflamed arterial wall. Heterogeneity of microvessels in NOS-3 regulation may be an additional determinant contributing to this compartmentalization and could explain the preferential targeting of newly generated capillary beds.

Might wasp venom desensitization induced Th2 to Th1 shift cause pregnancy failure?

The case of a 28-year-old woman under wasp venom desensitization having a premature birth in her 24th week of pregnancy 16 days after the last injection is described. To test the hypothesis that a special profile of immune cells in the decidua may trigger abortions, placental and decidual tissue sections were stained with antibodies against T cells (CD3), cytotoxic cells (CD8), natural killer cells (CD56), and mast cells, and an in-situ-hybridization was performed for tumor necrosis factor-alpha (TNF-alpha). CD56+ Natural killer cells were the dominating population. In earlier analyses of healthy first trimester decidua the percentage of NK cells and T cells was in a similar range, but the CD8:CD3 ratio was only 2.2% in contrast to 27% in the present case. Mast cells, which are known to be able to secrete abortogenic TNF-alpha, were only detectable in the decidua (10 cells/mm2) and decidua sections were TNF-alpha positive. Since SIT induces a shift of the interleukin and functional profile from a Th2 type towards a Th1 type, and pregnancy is dependent on a Th2 pronounced profile, SIT may trigger abortions or immature births. This is supported by the present results and might have happened in this case.