Expression levels of allergen genes during co-culture with macrophages. Aspergillus was co-cultured with macrophages at two different MOI - 1:200 and 1:2000 spores/macrophage for 48 h. RNA was extracted after 24 h and 48 h and qRT-PCR was used to determine allergen expression levels. Expression levels were calculated for Aspergillus exposed to macrophages (+M) and Aspergillus only samples for both time points. Expression levels are given as units relative to the comparator, β-tubulin (T) and this is shown for each gene tested to give an indication of level of expression. Error bars represent standard error of mean of biological replicates calculated using GraphPad PRISM 4.0.