Oral Lactobacillus strains reduce cytotoxicity and cytokine release from peripheral blood mononuclear cells exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro

• Background This study evaluated the effect of oral lactobacilli on the cytotoxicity and cytokine release from peripheral blood mononuclear cells (PBMCs) when exposed toAggregatibacter actinomycetemcomitanssubtypes in vitro.The supernatants and cell wall extracts (CWEs) of eightA. actinomycetemcomitansstrains, representing different subtypes, and threeLactobacillusstrains were used. The PBMCs from six blood donors were exposed to supernatants and CWEs ofA. actinomycetemcomitansorLactobacillusstrains alone or combinations and untreated cells as control. The cytotoxicity was determined by trypan blue exclusion method and IL-1 beta secretion by ELISA. TNF-alpha, IL-6, and IL-8 secretions were measured using Bioplex Multiplex Immunoassay. Results Supernatants or CWEs from all bacterial strains showed cytotoxicity and IL-1 beta secretion and the subtypes ofA. actinomycetemcomitansshowed generally a significantly higher effect on PBMCs than that of theLactobacillusstrains. Two highly toxicA. actinomycetemcomitansstrains (JP2 and JP2-like) induced a higher response than all other strains. When combined,Lactobacillussignificantly reduced the toxicity and the IL-1 beta secretion induced byA. acinomycetemcomitans. The effect varied between the subtypes and the reduction was highest for the JP2 and JP2-like strains. TheLactobacillus paracaseistrain SD1 had a higher reducing effect than the otherLactobacillusstrains. This strain had a consistent reducing effect on all subtypes ofA. actinomycetemcomitanscytotoxicity, and release of IL-1 beta, IL-6, IL-8, and TNF-alpha from PBMCs of the blood donors. A strong and significant variation in cytokine release between the six blood donors was noticed. Conclusions Lactobacillusspp. andL. paracaseiSD1 in particular, showed a limited but statistically significant reducing interaction withA. actinomycetemcomitanstoxicity and release of cytokines in vitro.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Odontologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Dentistry (hsv//eng)

Keyword

Microbial interaction

Oral lactobacilli

Aggregatibacter

actinomycetemcomitans

Bacterial toxicity

Cytokine release

Peripheral

blood mononuclear cells

actinobacillus-actinomycetemcomitans

dgge subtypes

aggregatibacter

periodontitis

serotypes

clone

Microbiology

Publication and Content Type

ref (subject category)

art (subject category)