title: Effects of extracellular slime produced by Staphylococcus epidermidis on oxidative responses of rabbit alveolar macrophages.
abstract: Bacterial slime produced in mass cultures of the RP 12 strain of Staphylococcus epidermidis was extracted with 4 M guanidine-HCl plus 0.05 M sodium acetate and 0.5% CHAPS, concentrated, dialyzed, and subjected to separation on DEAE sephacel columns. Three fractions, I-2A, I-2B, and I-4, were eluted with linear gradients of NaCl. Fractions I-2A and I-2B were alcian blue positive, whereas I-4 was alcian blue negative but the most electronegative fraction. The crude polysaccharide fraction and the three purified fractions were incubated individually for 2.5 or 20 h with normal rabbit alveolar macrophages (AM) to determine their effect on a subsequent PMA-induced oxidative burst. The crude fraction (50-200 micrograms/mL) and I-2B (50-200 micrograms/mL) primed the AM to give approximately a threefold increase in the PMA-induced burst after 2.5 h incubation. In contrast, a 20-h incubation resulted in a 30-40% inhibition of the PMA-induced burst with AM incubated with the same concentrations of the crude, I-2A, or I-2B fractions. Fraction I-4 had no detectable effect. The fractions also were tested to determine if they could elicit an oxidative burst in BCG-immune AM. None of the fractions (up to 500 micrograms/mL) elicited a significant oxidative burst even though BCG-immune AM yielded a PMA-induced burst 100 times that observed with normal resident AM. These data suggest that slime from S. epidermidis can impair the PMA-induced oxidative burst of normal AM during a 20-h incubation period and could explain in part why host defenses are compromised by slime-producing S. epidermidis.
authors.affiliation: Department of Microbiology and Immunology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27103.
authors.forename: Q N
authors.initials: QN
authors.lastname: Myrvik
authors.forename: W
authors.initials: W
authors.lastname: Wagner
authors.forename: E
authors.initials: E
authors.lastname: Barth
authors.forename: P
authors.initials: P
authors.lastname: Wood
authors.forename: A G
authors.initials: AG
authors.lastname: Gristina
mesh_terms: D000818:Animals; D005260:Female; D008163:Luminescent Measurements; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009163:Mycobacterium bovis / Q000276:immunology; D010084:Oxidation-Reduction; D011135:Polysaccharides, Bacterial / Q000302:isolation & purification / Q000494:pharmacology*; D011650:Pulmonary Alveoli / Q000166:cytology; D011817:Rabbits; D013212:Staphylococcus epidermidis / Q000032:analysis / Q000502:physiology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D011135:Polysaccharides, Bacterial; D013755:Tetradecanoylphorbol Acetate