Systemic antibodies to the leukotoxin of the oral pathogen Actinobacillus actinomycetemcomitans correlate negatively with stroke in women

• Background: Chronic infections and associated inflammatory markers are suggested risk factors for cardiovascular diseases (CVD) and stroke. The proinflammatory cytokine interleukin (IL)-1β is suggested to play a role in the regulation of local inflammatory responses in both CVD and periodontitis. The leukotoxin from the periodontal pathogen Actinobacillus actinomycetemcomitans has recently been shown to cause abundant secretion of IL-1β  from macrophages. The aim of the present study was to compare the prevalence of systemic antibodies to A. actinomycetemcomitansleukotoxin in stroke cases (n = 273) and matched controls (n = 546) in an incident case-control study nested within the Northern Sweden MONICA and Västerbotten Intervention cohorts. Methods: Antibodies to A. actinomycetemcomitans leukotoxin were analyzed in a bioassay with HL-60 cells (leukocytes), purified A. actinomycetemcomitans leukotoxin, and plasma. Plasma samples which inhibited lactate dehydrogenase release from leukotoxin-lysed cells by ≥50% were classified as antibody positive. Results: Antibodies to A. actinomycetemcomitans leukotoxin were detected in 18.8% of the women and 15.2% of the men. Women with those antibodies had a significantly decreased risk for stroke (OR = 0.28, 95% CI: 0.13–0.59), but not men (OR = 0.88, 95% CI: 0.52–1.51). Conclusion: The immunoreactivity to A. actinomycetemcomitans leukotoxin correlates negatively with a future stroke in woman, but not in men. Further studies are needed to explain the underlying mechanisms, as well as the biological relevance of this finding.

Nyckelord

Actinobacillus Infections/*epidemiology/*immunology

Actinobacillus actinomycetemcomitans/*immunology

Antibodies; Bacterial/blood

Case-Control Studies

Cerebrovascular Accident/*epidemiology/*immunology

Exotoxins/*immunology

Female

Humans

Male

Middle Aged

Periodontitis/immunology/microbiology

Risk Factors

Seroepidemiologic Studies

Sex Distribution

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)