Consistent with this result, we observed a significant increase in expression of COL1A1 in cocultured fibroblasts as measured by reverse transcription quantitative PCR (RT-qPCR); importantly, this phenotype was observed in both infections with C. trachomatis serovar L2 and serovar D (Fig. 5D), suggesting that infection-associated induction of fibroblast activity is conserved between anogenital and urogenital serovars of Chlamydia. Here, COL1A1 is linked to infection.