A comparison of the pulmonary defenses against streptococcal infection in rats and mice following O3 exposure: Differences in disease susceptibility and neutrophil recruitment

Journal Article · Wed Dec 01 00:00:00 EST 1993 · Toxicology and Applied Pharmacology; (United States)

DOI:https://doi.org/10.1006/taap.1993.1239· OSTI ID:5603785

Gilmour, M I; Selgrade, M K ^[1]

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1. Univ. of North Carolina, Chapel Hill (United States)

Ozone (O3) exposure reduces alveolar macrophage (AM) phagocytosis in mice and increases their susceptibility to Streptococcus zooepidemicus. O3 exposure also decreases AM phagocytosis in rats but does not result in mortality to infection. To investigate the mechanism of disease protection in rats, antibacterial defenses of two strains of mice and F344 rats were compared. O3 exposure (3 hr, 0.4 or 0.8 ppm) and infection with S. zooepidemicus resulted in a dose-dependent proliferation of bacteria in the lungs of mice and high mortality. Polymorphonuclear leukocytes (PMNs) were observed in severely affected individuals 2 or more days postinfection and did not alter the fatal infection. In contrast, microbial inactivation was only impaired in O3-exposed rat lungs during the first 48 hr after infection. In these animals PMNs could be isolated from bronchoalveolar lavage fluid between 6 and 48 hr postinfection with the peak response occurring at 24 hr. Pretreatment with anti-PMN serum eliminated the neutrophil influx and impaired further the bactericidal activity in ozone-exposed rats. The results suggest that inhaled streptococci are cleared normally from the mouse lung by AMs. Following exposure to O3, AM phagocytosis is reduced and the mice develop a fatal infection. The persistence of bacteria in the lungs of O3-exposed rats triggers a transient influx of PMNs whose appearance corresponds with elimination of the bacteria. Differences in antimicrobial defenses between various experimental species and humans need to be better understood in order to predict effects of air pollutants on susceptibility to infection in man.

• OSTI ID: 5603785
• Journal Information: Toxicology and Applied Pharmacology; (United States), Vol. 123:2; ISSN 0041-008X
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
OZONE
BIOLOGICAL EFFECTS
RESPIRATORY SYSTEM
DISEASE RESISTANCE
PHAGOCYTOSIS
ANTIMICROBIAL AGENTS
COMPARATIVE EVALUATIONS
DYNAMIC FUNCTION STUDIES
NEUTROPHILS
RESPONSE MODIFYING FACTORS
ANTI-INFECTIVE AGENTS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
DRUGS
EVALUATION
LEUKOCYTES
MATERIALS
560300* - Chemicals Metabolism & Toxicology
550900 - Pathology