C1QC and tuberculosis: Similarly, our data also showed upregulated expression of C1QB and C1QC genes and C1QA was less frequently observed in active TB, also in the analysis from Cai et al. the extend of increase in the expression of C1QA was less pronounced as compared to the increase in expression of C1QB and C1QC. Since C1q protein production requires equal ratios of all three chains, the detected increase in C1q protein levels in TB patients indicates that all chains are expressed.