Therefore, despite the association between the ELISA and ELISpot results, there is no absolute
correlation, as demonstrated by our results and those of others.27
Leyten et al have proposed that the two tests appear to differ in
their sensitivity for detecting cells producing low levels of IFNc,
which may partly explain these observed discrepancies.28
Bennekov et al demonstrated that, in an ELISA-based assay,
most of the IFNc produced came from a subset of cells and that
samples with similar ELISpot results could therefore have
different ELISA results. In animal models this observation was
also associated with different disease outcomes.29 Further
studies are therefore needed to assess the clinical relevance of
these findings.