Borrelia burgdorferi & Macrophages

Klemen Strle,1
Elise E. Drouin,1
Shiqian Shen,1
Joseph El Khoury,1,2
Gail McHugh,1
Eva Ruzic‐Sabljic,3
Franc Strle,4 and
Allen C. Steere1

Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, 2Infectious Diseases Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts; and 3Institute of Microbiology and Immunology, University of Ljubljana, 4Department of Infectious Diseases, University Medical Center Ljubljana, Ljubljana, Slovenia

To delineate the inflammatory potential of the 3 pathogenic species of Borrelia burgdorferi sensu lato, we stimulated monocyte‐derived macrophages from healthy human donors with 10 isolates each of B. burgdorferi, Borrelia afzelii, or Borrelia garinii recovered from erythema migrans skin lesions of patients with Lyme borreliosis from the United States or Slovenia. B. burgdorferi isolates from the United States induced macrophages to secrete significantly higher levels of interleukin (IL)‐8, CCL3, CCL4, IL‐6, IL‐10, and tumor necrosis factor than B. garinii or B. afzelii isolates. Consistent with this response in cultured macrophages, chemokine and cytokine levels in serum samples of patients from whom the isolates were obtained were significantly greater in B. burgdorferi–infected patients than in B. afzelii– or B. garinii–infected patients.

These results demonstrate in vitro and in vivo that B. burgdorferi has greater inflammatory potential than B. afzelii and B. garinii, which may account in part for variations in the clinical manifestations of Lyme borreliosis.

Received 28 April 2009; accepted 6 July 2009; electronically published 12 November 2009.

Reprints or correspondence: Klemen Strle, Massachusetts General Hospital, 55 Fruit St, CNY149/8301, Boston, MA 02114 (kstrle@partners.org).

http://www.journals.uchicago.edu/doi/abs/10.1086/648091