Effect of sonicated material from Fusobacterium nucleatum on the functional capacity of accessory cells derived from dental pulp

Abstract

Fusobacterium nucleatum-derived components were studied for their effect on the ability of accessory pulpal cells to induce T-lymphocyte proliferation. In initial experiments, spleen cells were used to establish concentration ranges at which testing of the effect of the bacterial components would be suitable. At low concentrations, bacterial substances induced a stimulatory effect on the proliferation rate of spleen cells, but not when purified T-lymphocytes were incubated in the presence of concanavalin A and pulpal accessory cells. At increasing concentrations, a dose-dependent reduction was observed. Pretreatment with the bacterial products for 4 h gave a stimulatory effect in the absence of concanavalin A for both spleen cells and T-lymphocytes. Removal of low-molecular weight components (<3.5 kDa) did not influence the inhibitory effect, whereas preheating the bacterial substances to 100 degrees C eliminated the observed inhibition. Findings show that heat-sensitive, high-molecular-weight components of F. nucleatum can evoke a concentration-dependent stimulatory or suppressive effect on the proliferation rate of T-lymphocytes in the presence of accessory cells derived from the dental pulp.

Effect of sonicated extracts ofEnterococcus faecalison the production of matrix metalloproteinase-8 by human polymorphonuclear neutrophils

“…For example, sonicated material of Fusobacterium nucleatum can evoke a concentrationdependent stimulatory or suppressive effect on the proliferation rate of accessory cell 14) . Sonicated extract of Actinobacillus actinomycetemcomitans suppressed interleukin-2 production of T-cells 15) .…”

The effect ofTreponema denticolaimmunoinhibitory protein on cytokine expression in T cells

“…There are accumulating evidences that pathogenic bacteria associated with endodontic infection and have been shown to alter the host defense system. For example, Yoshida et al 13) reported that sonicated material from Fusobacterium nucleatum can either suppress or stimulate T cell proliferation in the presence of dental pulp accessory cells. Likewise, Gentry-Weeks et al 21) reported that Enterococcus faecalis can survive in mouse peritoneal macrophages.…”

“…IL-2 stimulates T cells proliferation and involved in cell mediated immunity while IL-4 promotes the B cell to differentiate into plasma cell that produces antibodies and thus mediating humoral immunity 9) . Recent studies [10][11][12][13] have investigated that the suppression of lymphocyte proliferation by pathogenic bacteria related to endodontic treatment failures. Furthermore, Lee et al 14) clearly showed that immunoinhibitory protein extracted from T. denticola suppressed proliferative ability of lymphocytes by arresting cell cycle.…”

Effects ofEnterococcus faecalissonicated extracts on IL-2, IL-4 and TGF-β1 production from human lymphocytes

“…Bacterial fractions were prepared as previously described 7) . Briefly, bacterial cells harvested from 1-liter cultures were washed, suspended in 20 ㎖ of phosphate-buffered saline (PBS), to minimize the loss of protein, 1 mM of Phenylmethylsul-fonylfluoride (PMSF) were added.…”

“…In previous studies, sonic extracts from bacteria were studied for their effects on the immune response. For example, sonicated material of Fusobacterium nucleatum can evoke a concentration-dependent stimulatory or suppressive effect on the proliferation rate of accessory cell 7) . Sonicated extract of Actinobacillus actinomycetemcomitans suppressed interleukin-2 production of Tcells 8) .…”