Interleukin-7 production by B lymphocytes affects the T cell-dependent osteoclast formation in an in vitro model derived from human periodontitis patients

Int J Immunopathol Pharmacol. 2005 Jul-Sep;18(3 Suppl):13-9.

Abstract

Periodontitis is characterized by irreversible destruction of alveolar bone and connective tissue attachment in the periodontium. We recently reported that T cells support the osteoclastogenesis by the overproduction of nuclear factor-kappa-B-ligand (RANKL) and Tumor Necrosis Factor-alpha (TNF-alpha) in an in vitro osteoclastogenesis model from periodontitis patients (Pp). It is known that IL-7 stimulates the production of osteoclastogenic factors by T cells and IL-6 potentiates IL-7 expression. Thus, we studied the involvement of IL-6 and IL-7 in the T cell regulation of osteoclast (OC) formation, in an in vitro osteoclastogenesis model from Pp. We demonstrated high levels of IL-7 in both the media collected from PBMC cultures of Pp and the sera of the same patients. We also demonstrated that freshly isolated B cells from PBMCs of Pp were the source of IL-7 in our model. B cells, in fact, overexpressed IL-7 at mRNA and protein levels, and this production was up-regulated by IL-6. Moreover, the OC formation decreased in the presence of anti-IL-6 and IL-7 functional antibodies in PBMC cultures from Pp. These data suggest that B cells could be responsible for the T cell-dependent osteoclastogenesis in periodontitis through the involvement of IL-6 and IL-7.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • B-Lymphocytes / immunology*
  • Cells, Cultured
  • Female
  • Humans
  • Interleukin-6 / pharmacology
  • Interleukin-7 / physiology*
  • Male
  • Middle Aged
  • Osteoclasts / physiology*
  • Periodontitis / immunology*

Substances

  • Interleukin-6
  • Interleukin-7