Polyclonal human T-cell activation by silicate in vitro

Immunology. 1994 Jun;82(2):332-5.


Silica (SiO2) or related substances such as silicone ([-R2Si-O-]n), which is used in plastic surgery, or asbestos (e.g. chrysotile; 3MgO.2SiO2.H2O) have 'adjuvant effects'. In a study of scleroderma patients in Germany more than 78% had experienced exposure to silicate dust. T-cell receptor (TcR) V beta gene analysis on CD4- CD8- double-negative alpha beta T cells from scleroderma patients, using polymerase chain reaction (PCR), showed that certain V beta genes, V beta 5, V beta 7 and V beta 17, were predominantly expressed in the cells. We found that certain V beta repertoires, V beta 5.3 and V beta 6.7, were predominantly expressed on fractionated T cells with a high Ca2+ level that had been stimulated by chrysotile in vitro. The intracellular Ca2+ level in human peripheral blood mononuclear cells (PBMC) increased after incubation with silica or chrysotile. Interleukin-2 (IL-2) release from PMBC also rose significantly with chrysotile stimulation, but no change was observed when major histocompatibility complex (MHC) class II DP/DR positive cells were depleted. Therefore, our results support the possibility that silicate acts as a superantigen.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asbestos, Serpentine / immunology*
  • Calcium / blood
  • Cells, Cultured
  • Female
  • Humans
  • Interleukin-2 / blood
  • Lymphocyte Activation / immunology*
  • Male
  • Receptors, Antigen, T-Cell, alpha-beta / analysis
  • Receptors, Antigen, T-Cell, alpha-beta / genetics
  • Silicon Dioxide / immunology*
  • Superantigens / immunology
  • T-Lymphocytes / immunology*


  • Asbestos, Serpentine
  • Interleukin-2
  • Receptors, Antigen, T-Cell, alpha-beta
  • Superantigens
  • Silicon Dioxide
  • Calcium