The Influence of Mineral Trioxide Aggregate on Adaptive Immune Responses to Endodontic Pathogens in Mice

Abstract

This study assessed the influence of mineral trioxide aggregate (MTA) on adaptive immune responses. BALB/c mice were immunized with heat-killed Fusobacterium nucleatum (Fn) in MTA or other control adjuvants, and serum IgG responses to Fn were measured. Either Fn-or Peptostreptococcus anaerobius (Pa)-reactive memory T cells (Tm) were pre-incubated in vitro with/ without MTA and restimulated with Fn or Pa. Tm proliferation and cytokine production were assessed. Compared to control groups, IgG-antibody responses were upregulated in mice immunized with Fn in MTA in a similar manner to animals immunized with Fn in Freund's adjuvant or aluminum hydroxide adjuvant. While MTA did not affect the upregulated expression of IL-10, TNF-α or RANKL by Tm, it suppressed the proliferation of Pa-or Fn-Tm and inhibited their production of Th1-or Th2-signature cytokines. MTA upregulated the adaptive humoral immune responses, but had little or no effect on pro-or anti-inflammatory cytokine production by Tm.

Effect of Mineral Trioxide Aggregates and Portland Cements on Inflammatory Cells

“…MTA induces inflammation via a transcription factor nuclear factor-kappa B signaling system (25). MTA up-regulates the adaptive humoral immune response (26). Accorinte et al (27) showed that although pulp healing with calcium hydroxide is slower than with MTA, both materials are good for pulp capping in human teeth.…”

Influence of Selective Immunosuppressive Drugs on the Healing of Exposed Dogs' Dental Pulp Capped with Mineral Trioxide Aggregate

“…This could explain the worse results of groups that received mycophenolate mofetil, sirolimus, and cyclosporine A. MTA is biocompatible material that does not interfere with the normal reparative mechanism for pulp healing. Some authors (7,41) stated that it might promote healing and allow cytokine release. Immunosuppressive drugs (mycophenolate mofetil, sirolimus, cyclosporine A) might interfere with repair mechanism through their negative effect on cytokine release.…”

Bacteria-reactive Immune Response May Induce RANKL-expressing T Cells in the Mouse Periapical Bone Loss Lesion

“…C57BL/6j mice (8-week-old males, n=5/group) were immunized with or without heat-killed Pasteurella pneumotropica (P. pneumotropica) or Enterococcus saccharolyticus ( E. saccharolyticus ) (3×10 8 CFU/mouse, subcutaneous [s.c.] injection) in Freund’s adjuvant following the method previously published (17). Four days after booster injection (s.c.) of bacteria in PBS, lymph nodes and blood serum were isolated.…”

“…Sera isolated from mice were reacted to heat-killed bacteria (10 7 /ml) coated on ELISA plates, and the reacted serum IgG antibodies were measured by ELISA (17). …”

“…T-cells (2×10 5 cells/well) isolated from the lymph nodes of mice immunized with or without P. pneumotropica or E. saccharolyticus were co-cultured in vitro with Mitomycin C (20 µg/ml, Sigma)-treated DCs (2×10 4 cells/well) in the presence or absence of fixed P. pneumotropica or E. saccharolyticus (10 7 CFU/well) in RPMI 1640 medium containing 10% FBS for 3 days (17). The proliferation of T-cells was evaluated by the [ 3 H] thymidine incorporation assay (18).…”