TLR2 agonists inhibit fibrocyte differentiation. Human PBMCs were cultured in different concentrations of the TLR2 agonists Pam3CSK4, HKLM, lipomannans from Mycobacterium smegmatis (LM-MS), LTA, PG-LPS and FSL-1. After 5 days, the cells were air-dried, fixed and stained, and the number of fibrocytes was counted. The results are means ± SEM of fibrocytes per 2.5 × 105 PBMCs (n = 6 separate experiments for Pam3CSK4 and n = 3 separate experiments for the rest of the TLR2 agonists). The absence of error bars indicates that the error was smaller than the plot symbol. Statistical significance was analyzed by ANOVA using Dunnett's test to compare values against the no-agonist control for all the agonists except LM-MS, which was analyzed by t-test. *P < 0.05, **P < 0.01, and ***P < 0.001 compared to no-agonist control. Arrows indicate the concentration of TLR2 agonists used by other workers (Table 1).