Poppers: More Evidence of Suppressed Immunity

Four months ago AIDS Treatment News noted a toxicology study finding increased cancer in mice exposed to isobutyl nitrite, in concentrations approximating social use of the drug--apparently due to suppression of immune responses that would normally control the cancer, not direct stimulation of cancer cells1 ("Poppers: Large Cancer Increase and Immune Suppression in Animal Tests," AIDS Treatment News #317, April 16, 1999). Now another study2 has found increased bacterial growth, and further evidence of immune suppression. At a recent meeting in Amsterdam, researchers reported that isobutyl nitrite inhalation "results in increased bacterial growth in the lungs and livers of infected mice, suppresses the ability of mediastinal lymph nodes to respond to antigen-specific stimulation, and may reduce the CD4+ and CD8+ T cell populations in the mediastinal lymph nodes after pulmonary infection with Listeria monocytogenes."

This study was supported by the U.S. National Institutes of Health.


References
1. Soderberg LSF. Increased tumor growth in mice exposed to inhaled isobutyl nitrite. Toxicology Letters, 1999; volume 104, pages 35-41.

2. Schafer R, Barnett J, Soderberg L, and Damiani C. Pulmonary exposure to isobutyl nitrite reduces resistance to a respiratory infection. 10th International Congress of Mucosal Immunology, Amsterdam, June 27 to July 1, 1999.