title: Calprotectin, an abundant cytosolic protein from human polymorphonuclear leukocytes, inhibits the growth of Borrelia burgdorferi.
abstract: We previously showed that numerous polymorphonuclear leukocyte (PMN) granule components efficiently kill Borrelia burgdorferi, the agent of Lyme disease. In addition, motile, granule-poor cytoplasts (U-Cyt) from human blood PMN can exert anti-Borrelia activity against opsonized B. burgdorferi independently of oxidative mechanisms. Here we show that lysates of U-Cyt also possess anti-Borrelia activity, a portion of which comes from the abundant cytosolic protein calprotectin. The anti-Borrelia activity of U-Cyt lysates and recombinant calprotectin was partially or completely reversed by specific antibody to calprotectin and by Zn(2+), a cation essential for the growth of B. burgdorferi and known to inhibit the antimicrobial activity of calprotectin. Quantitative microscopic and regrowth assays revealed that calprotectin acted in a bacteriostatic fashion against B. burgdorferi. We conclude that calprotectin, a potent bacteriostatic agent from a cell primarily recognized for its oxidative and granular antibacterial mechanisms, may play a modulatory role in infection by the Lyme spirochete, particularly at sites of acute inflammation.
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
authors.forename: Denise
authors.initials: D
authors.lastname: Lusitani
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Malawista
authors.forename: Ruth R
authors.initials: RR
authors.lastname: Montgomery
mesh_terms: D000900:Anti-Bacterial Agents / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D025065:Borrelia burgdorferi / Q000187:drug effects* / Q000254:growth & development / Q000276:immunology / Q000472:pathogenicity; D003600:Cytosol / Q000276:immunology; D006801:Humans; D066298:In Vitro Techniques; D039841:Leukocyte L1 Antigen Complex / Q000276:immunology / Q000302:isolation & purification / Q000494:pharmacology*; D009504:Neutrophils / Q000276:immunology* / Q000382:microbiology*; D015032:Zinc / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D000911:Antibodies, Monoclonal; D039841:Leukocyte L1 Antigen Complex; D015032:Zinc