title: Bacterial endosymbionts of Onchocerca volvulus in the pathogenesis of posttreatment reactions.
abstract: Treatment of onchocerciasis with diethylcarbamazine (DEC) or ivermectin is associated with a posttreatment reaction characterized by fever, tachycardia, hypotension, lymphadenopathy, and pruritus. To investigate the role of the Wolbachia bacterial endosymbiont of Onchocerca volvulus in these reactions, serum samples collected before and after treatment with either anthelmintic were assessed for evidence of Wolbachia DNA. By use of real-time quantitative polymerase chain reaction, Wolbachia DNA was detected in both groups-with significantly higher levels in those who received DEC (P <.0001). In the ivermectin group, there was a significant correlation between levels of bacterial DNA and serum tumor necrosis factor-alpha (P =.013). Peak DNA levels correlated with reaction scores (P =.048). Significant correlations were also seen between Wolbachia DNA and the antibacterial peptides calprotectin (P =.021) and calgranulin B (P <.0001). These findings support a role for Wolbachia products in mediating the inflammatory responses seen following treatment of onchocerciasis and suggest new targets for modulating these reactions.
authors.affiliation: Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. pkeiser@niaid.nih.gov
authors.forename: Paul B
authors.initials: PB
authors.lastname: Keiser
authors.forename: Stacey M
authors.initials: SM
authors.lastname: Reynolds
authors.forename: Kwablah
authors.initials: K
authors.lastname: Awadzi
authors.forename: Eric A
authors.initials: EA
authors.lastname: Ottesen
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Taylor
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Nutman
mesh_terms: D000293:Adolescent; D000328:Adult; D002135:Calcium-Binding Proteins / Q000097:blood; D040502:Calgranulin B; D004269:DNA, Bacterial / Q000032:analysis; D004049:Diethylcarbamazine / Q000009:adverse effects*; D005369:Filaricides / Q000009:adverse effects*; D006801:Humans; D007559:Ivermectin / Q000009:adverse effects*; D039841:Leukocyte L1 Antigen Complex; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood; D019006:Neural Cell Adhesion Molecules / Q000097:blood; D009855:Onchocerciasis / Q000188:drug therapy* / Q000276:immunology; D013559:Symbiosis; D020577:Wolbachia / Q000472:pathogenicity*
chemical_list: D002135:Calcium-Binding Proteins; D040502:Calgranulin B; D004269:DNA, Bacterial; D005369:Filaricides; D039841:Leukocyte L1 Antigen Complex; D008562:Membrane Glycoproteins; D019006:Neural Cell Adhesion Molecules; D007559:Ivermectin; D004049:Diethylcarbamazine