FIG. 4.

HMSCs secreted IL1β and IL6 to regulate cell aggregation structure formation potentially through regulating NF-κB in HUVECs. (A, B) Relative mRNA expressions of IL1β and IL6 in HMSCs and HUVECs after coculture within 24 h. (C, D) Secretion levels of IL1β and IL6 in culture medium after coculture within 24 h. (E, F) Effect of siRNA targeting IL1β and IL6 on secretion of IL1β and IL6 in culture medium. MSCs and ECs were pretreated with siRNA targeting IL1β, IL6, or negative scramble siRNA as indicated. (G) Effect of neutralizing IL1β, IL6, and both on coculture-induced NF-kB activation in co-HUVECs. Left: representative western blot analysis of p65 (RelA) nucleus translocation in co-HUVEC at 24 h after treatment of scramble IgG, Anti-IL1β, Anti-IL6, or both; right: quantification of nucleus/cytoplasmic ratio of p65 via signal intensity. (H) Left: representative images of coculture-induced cell aggregation structure formation at 24 h after neutralizing IL1β, IL6, or both in medium. Right: cell aggregation structure trends were quantified for each indicated groups. * Indicates P-value <0.05, ** indicates P-value <0.01. IL, interleukin.