No abstract

Cells containing immunoglobulin E (IgE) were enumerated and their location in mouse lungs was determined by direct immunofluorescence. Lungs were studied from mice that had been immunized with aerosolized ovalbumin as well as from normal mice and from mice that were exposed to ozone (0.5 or 0.8 ppm) prior to receiving aerosolized antigen. In addition, some mice were immunized intraperitoneally with ovalbumin precipitated in alum. IgE-containing cells were primarily airway-related in normal mice and in mice immunized by the intraperitoneal route. Lungs from aerosol-immunized, and aerosol-immunized and ozone-exposed mice showed a more disseminated distribution of IgE-containing cells. Fluorescent cells were counted and numbers were expressed as total cells per square millimeter of lung tissue and as airway-associated cells per millimeter of airway. Total IgE cells increased 9.4-fold in mice that received aerosolized ovalbumin as compared to normal mice. When ozone exposure was added to the effects from aerosolized ovalbumin, the increase of IgE cells over normal was 34.2-fold. IgE cell counts correlated well with anaphylactic sensitivity to intravenous challenge with ovalbumin. The observed enhancement of allergic sensitization by ozone exposure has important implications for human health.

Inhaled ozone was found to exert an enhancing effect for allergic lung sensitization when mice contacted an aerosolized allergen. The animals were exposed to ozone concentrations of 0.24, 0.16, 0.13, and 0.10 ppm. After 4 days of continuous ozone exposure, the mice had allergen contact from an aerosolized solution of ovalbumin. The animals were then maintained in ambient air for several days before the cycle of ozone and aerosolized allergen was repeated over four allergen contact cycles. Mice were rested in ambient air for a week after the last allergen contact, and they were then tested for allergic sensitization by the intravenous injection of 2 mg of ovalbumin to induce anaphylactic shock in allergic individuals. The control groups of mice were maintained in ambient air throughout the experiment, but they experienced identical allergen contact with the ozone-exposed mice. The phenomenon of allergic enhancement from ozone inhalation was detected at 0.24, 0.16, and 0.13 ppm of ozone. The enhancing effect disappeared at 0.10 ppm of ozone. The study indicated a potential for increasing the number of allergically sensitized individuals when various allergens are inhaled during periods of high ozone exposure with the consequent adverse changes on respiratory membranes. The significance to human health of the allergic enhancement phenomenon by Ozone needs investigation.

Ozone was added to the air of the environmental chambers containing specific pathogen-free mice. At levels of 0.5 and 0.8 ppm the oxidant was seen to have inflammatory effects, as shown by rising serum albumin levels in lung lavage fluid. Fluorescein conjugated anti-heavy chain sera were used to detect cells containing IgM, IgG, and IgA in measured lung areas termed Pulmonary Units. Antigenic stimuli occurred along the airways, with significant increases of IgA-containing cells in the bronchus-associated lymphoid tissue. The numbers of IgM- and IgG-containing cells did not increase. Immunodiffusion analyses for immunoglobulins in lung lavage fluid indicated increases of IgG1, IgG2, and IgA in lung secretions. The calculation of changing Ig/Alb ratios suggested that the IgA present was largely the result of local synthesis, while IgG molecules were mainly of serum origin. Possible sources of antigenic stimuli to ozone-exposed lungs are discussed.

patterns of mice injected with ATS and AMS and inoculated with Listeria monocytogenes were determined. The immunosuppressive qualities of the antisera were compared with their leukocytotoxicity titers. MATERIALS AND METHODSAnimals. Mice used in the experiments were the progeny of brother-sister matings from a colony of the inbred Balb/c strain. All antisera were produced in young adult New Zealand white rabbits.Bacteria. Stock cultures of L. monocytogenes strain 3-54 (serotype 4b) were maintained on tryptose agar slants at -20 C. Suspensions for animal inoctulations were prepared by growing the bacteria in Trypticase soy broth for 18 to 24 h at 37 C. The bacteria were washed twice in Zobell solution (40), and the optical density of the suspension was then adjusted to the desired value. The number of viable bacteria in the suspension was determined by a drop-plate method (31). All inoculations of L. monocytogenes and injections of sera were given by the intraperitoneal route (26). 479on August 5, 2020 by guest http://iai.asm.org/ Downloaded from