CGB - Universidad Mayor

18 noviembre 2019

Inhibitory effect of serotype a of Aggregatibacter actinomycetemcomitans on the increased destructive potential of serotype b.

DOI : 10.1111/odi.13237


OBJECTIVE: The serotype b of Aggregatibacter actinomycetemcomitans (A.

actinomycetemcomitans) induces higher cytokine production in dendritic cells

(DCs) compared with the other serotypes. However, this increased

immunostimulatory potential was modified when DCs were co-infected with the

other A. actinomycetemcomitans serotypes. This study aimed to analyze whether

the production of interferon gamma (IFN-γ), C-reactive protein (CRP), matrix

metalloproteinase (MMP)-2, and MMP-9, as well as the activity of osteoclasts,

also varies when DCs are co-infected with the A. actinomycetemcomitans


MATERIALS AND METHODS: Human DCs were stimulated with the A.

actinomycetemcomitans serotypes using the following stimulatory conditions:

serotype a/b/c/a+b/a+c/b+c/a+b+c. The IFN-γ, CRP, and MMP-2 levels were

quantified by ELISA. The active form of MMP-9 was quantified using fluorescent

functional assays. The MMP-2 gelatinolytic activity was identified by zymogram.

The osteoclast activity was determined by quantifying the TRAP expression and

resorption-pit formation using cytochemistry and osteoassays.

RESULTS: Higher levels of IFN-γ, CRP, MMP-2, MMP-9, and osteoclast activity were

detected when DCs were stimulated with the serotype b of A.

actinomycetemcomitans compared with the others. This increased immunostimulatory

potential attributed to serotype b diminished when DCs were co-infected with the

serotype a.

CONCLUSIONS: This study provides new insights into the virulence of A.

actinomycetemcomitans and reveals important differences in the immunostimulatory

and pro-destructive potential among its serotypes.

Investigadores Participantes del Centro



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