Immunolocalization of transforming growth factor-beta 3 in pregnant human myometrium

Transforming growth factor-beta 3 is a cytokine which is involved in cell growth regulation and differentiation, stimulation of extracellular matrix and modulation of immune responses. The goal of this study was to detect the presence of this cytokine in the myometrium of preterm and term, nonlaboring and laboring patients, and to measure serum levels of interleukin-1 beta (IL-1 beta), IL-6 and IL-8 before cesarean section.

In this prospective study, we obtained samples of myometrium from the lower uterine segment during elective and emergency cesarean sections (term non-laboring, n=8; term laboring, n=7; preterm non-laboring, n=3; and preterm laboring, n=19) and stained for transforming growth factor-beta 3. Blood was also sampled from the same patients to determine IL-1 beta, IL-6 and IL-8 levels.

Different intensities of staining were detected in preterm laboring, term nonlaboring and term laboring groups, but there was no staining in preterm nonlaboring group. We also found a statistically significant difference in IL-6 levels between laboring and nonlaboring groups (p=0.028).

Different intensities of TGF-beta 3 which appeared in different stages of myometrium made us consider that TGF-beta 3 might prepare myometrium to labor, and IL-6 was more important than the other interleukins in initiation of labor.