Complement evasion by Borrelia burgdorferi: it takes three to tango

Abstract

Complement evasion by Borrelia burgdorferi: it takes three to tango Steven W. de Taeye1,2, Lieselotte Kreuk1, Alje P. van Dam3, Joppe W. Hovius1,4, and Tim J. Schuijt1,4 1 Center for Experimental and Molecular Medicine, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands 2 Experimental Virology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands 3 Department of Medical Microbiology, Onze Lieve Vrouwe Gasthuis, Amsterdam, 1091 AC, The Netherlands 4 Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06420, USA The complement system is one of the major innate defense mechanisms Borrelia burgdorferi sensu lato has to overcome to establish an infection of mammalian hosts and to cause Lyme borreliosis in humans. Borrelia prevents complement-mediated killing during host col- onization through (i) recruitment of host complement regulators by Borrelia, (ii) evasion mechanisms by Bor- relia itself, and (iii) exploitation of tick proteins by Bor- relia. These interactions with complement can be host species-specific. This review provides an overview of interactions between Borrelia, tick, and host leading to evasion of complement-mediated killing. Borrelia and Lyme borreliosis Lyme disease or Lyme borreliosis has become the most common tick-borne disease in the USA and Europe [1]. In endemic areas, the prevalence of Lyme borreliosis has been estimated to range from 20 to 100/100 000 people in the USA and from 100 to 130/100 000 in Europe [2]. Lyme borreliosis is a zoonotic disease caused by spirochetes of the Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) complex [3]. In the USA, B. burgdorferi sensu stricto (s.s.) causes Lyme borre- liosis, whereas in Europe, in addition to B. burgdorferi s.s., other genospecies, for example, Borrelia afzelii, Borrelia garinii, Borrelia bavariensis, and Borrelia spielmanii, are the major Lyme borreliosis-causing sp