Fig 4.

Induction of CRACC protein on NK cell surfaces is mediated by DCs. (A) Primary human NK cells were incubated (24 h) with or without washed primary human DCs previously challenged with either A. actinomycetemcomitans (A.a.) or P. gingivalis (P.g.) or left uninfected (multiplicity of infection [MOI], 100). Coculture of NK cells with infected DCs resulted in induction of CRACC protein on NK cell surfaces. However, the induction was far more pronounced in response to A. actinomycetemcomitans than P. gingivalis challenge. (B) Dose-dependent induction of CRACC in response to coculture with different numbers of DCs previously infected with A. actinomycetemcomitans. NK cells were incubated with or without A. actinomycetemcomitans at an MOI of 100 and in coculture with or without DC in different cell ratios. n = 4; 1-way repeated-measures analysis of variance with post hoc Dunnett test. *, P < 0.05; ***, P < 0.001.