Autoimmune thyroid diseases feature prominent cellular infiltration of the
thyroid gland as well as autoantibody production to thyroid antigens. The m
ost common assay to evaluate cell-mediated immunity is based on incorporati
on of tritiated thymidine into proliferating T cells after stimulation by t
he test antigens. In the past, cell proliferation assays of thyroglobulin (
Tg) using peripheral blood mononuclear cells (PBMC) of individuals with aut
oimmune thyroid diseases required large quantities of blood and specialized
separation techniques, and have not yielded high counts or high stimulatio
n indices. We therefore developed a proliferation assay using less than 5 m
L of whole blood and compared proliferation of cells in whole blood to that
using PBMCs separated by density gradient centrifugation. We also determin
ed if responses could be enhanced by addition of interleukin-2 (IL-2) to th
e cultures. We found that an IL-2-stimulated proliferation assay to Tg usin
g diluted whole blood is superior to the separated cell assay in detecting
Tg-specific T-cell proliferation in autoimmune thyroid disease patients. Fu
rther refinement of this technique and larger trials may confirm its value
for clinical investigation and special diagnostic applications.