qPCR analysis of rabbit genes involved in the Th1 and Th2 type immune response. cDNA was synthesized from the total lung RNA from pooled, uninfected (n = 3) and three independent biological replicates of Mtb-infected rabbits at each time point (2, 4, 8 and 12 weeks post-infection) and used in the qPCR experiments. Genes involved in Th1 (A) and Th2 (B) type immune response were selected from published literature. Gene-specific oligonucleotide primers were used to amplify the test genes. Levels of GAPDH in each sample were used to normalize the expression of test genes. Relative gene expression was calculated from the expression levels of each test gene in the uninfected (naïve) and Mtb-infected samples after normalization against GAPDH levels. The experiments were repeated at least three times with lung total RNA from three biological replicates. Values plotted are median ± standard error.