In vitro model for modulation of helper T cell differentiation and activation.

Influence of immunotoxicants on helper T cell reactivities can be investigated by assessing acquisition of IL-4- or IFN-γ-producing ability in vitro with antigen-primed naive or precursor helper T cells from the spleens of DO11.10 ovalbumin-specific transgenic mice. The in vitro differentiation model is believed to be close to the in vivo environmental conditions in which differentiation occurs. The effect of immunotoxicants on helper T cell activity can also be evaluated by antigen-specific activation of cloned type-1 or type-2 helper T cells in vitro, since the two subsets of helper T cells can be distinguished by patterns of cytokine secretion. This in vitro model will help investigators to examine the ability of toxicants to modulate helper T cell-mediated cellular or humoral immunity.