A heatmap depicting the top 100 modulated genes that were differentially expressed between DBA/2 and C57BL/6 mice. Fold changes were calculated between mice strains prior to (day 0) and following infection (days 10, 14, and 16) with C. immitis. For each gene, the absolute peak log2 fold change (FC) was identified across time points and the top 100 included in the heatmap. The log2 fold change scale is indicated at the bottom of the heatmap, where red shading indicates greater expression in DBA/2 compared to C57BL/6 mice and blue shading represents lesser expression. For example, red shading will result if a gene is expressed to a greater extent in DBA/2 compared to C57BL/6 mice or if a constitutively expressed gene is downregulated in DBA/2 to a lesser extent compared to C57BL/6. Therefore, the direction of gene expression changes for each of the top 100 modulated genes is presented in Additional file 1: Figure S1 by dividing expression levels at post-infection time points (day 10, 14, and 16) by those in the uninfected control (day 0). Hierarchical clustering of genes based on their expression profiles over the time course is reflected in the dendogram to the right of the heatmap and was performed by calculating distances using the Pearson correlation metric and then clustering distances using the average linkage method. The expression of genes marked with an asterisk (*) was confirmed by RT-qPCR. Annotation columns are as follows: FC, peak log2 fold change; GS, gene symbol; FGN, full gene name.