Analysis of the immune response against tetanus toxoid: enumeration of specific T helper cells by the Elispot assay

Immunobiology. 2002 Jul;205(3):282-9. doi: 10.1078/0171-2985-00131.


Tetanus toxoid (TT) is an antigen known to induce strong T cell specific immune responses in humans after vaccination. Here we have used the Elispot assay to assess the number of TT-specific Interferon-gamma (IFN-gamma) secreting T cells present in individuals and monitored the number of TT specific T cells present in the donors for more than two years. In each of the 22 healthy volunteers tested, TT-specific T cells could be detected. Six out of 7 repetitively tested donors showed a remarkably constant number of TT-specific IFN-gamma secreting T cells over several months, whereas one donor demonstrated a transient increase during a flu-like infection. Three healthy donors received TT booster-immunizations and showed significant increases in the number of TT-specific IFN-gamma secreting T cells which reached peak levels by 4 weeks after vaccination. Depletion of either CD4+ T cells, CD8+ T cells or CD16+/CD56+ T cells by immunomagnetic separation demonstrated that TT-specific IFN-gamma secretion is mediated exclusively by CD4+ T cells. In addition, HLA class-I and -II blocking studies showed that IFN-gamma production is performed by HLA class-II restricted cells. Our data show that the Elispot assay can be reliably used to assess the number of TT-specific CD4+ IFN-gamma producing cells (i.e. probably T helper cells) and therefore maybe also useful for the assessment of reactions to other helper antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Assay*
  • CD4-Positive T-Lymphocytes / immunology
  • Humans
  • Interferon-gamma / metabolism
  • T-Lymphocytes, Helper-Inducer / immunology*
  • Tetanus Toxoid / immunology*


  • Tetanus Toxoid
  • Interferon-gamma