REGULATION OF DECIDUAL CELL CHEMOKINE PRODUCTION BY GROUP-B STREPTOCOCCI AND PURIFIED BACTERIAL-CELL WALL COMPONENTS

OBJECTIVE: Our purpose was to determine whether cultured human decidua l cells produce chemokines in response to different strains of group B streptococci and purified bacterial cell wall components. STUDY DESIG N: Human decidual cells were cultured from term placentas by standard techniques. Different strains of group B streptococci were isolated fr om neonates with early-onset group B streptococci sepsis. Confluent ce ll monolayers were incubated with these different strains of group B s treptococci and various concentrations of purified bacterial cell wall components (including lipoteichoic acid, sialic acid, lipopolysacchar ide, and lipid A) for 16 hours at 37 degrees C. Culture supernatants w ere collected and assayed for macrophage inflammatory protein-1 alpha and interleukin-8. Statistical analysis was by analysis of variance. R ESULTS: We found that cultured human decidual cells produced significa nt amounts of the two chemokines macrophage inflammatory protein-1 alp ha and interleukin-8 in a strain-specific fashion to the various diffe rent strains of group B streptococci tested, from 215% to 421% over ba seline production (p < 0.05 by analysis of variance). Also, we found t hat incubation of decidual cells with various concentrations of lipote ichoic acid, sialic acid, lipopolysaccharide, and lipid A resulted in significant concentration-dependent increases in decidual cell macroph age inflammatory protein-1 alpha and interleukin-8 production (p < 0.0 5.) CONCLUSIONS: Decidual cells produced significant amounts of the ch emokines macrophage inflammatory protein-1 alpha and interleukin-8 in response to intact group B streptococci in a strain-specific fashion a nd in response to various concentrations of different bacterial cell w all components, Because chemokines are important mediators signaling m igration of different immune effector cells into areas of inflammation , we suggest that decidual cell chemokine production in response to ba cteria and bacterial cell wall components may be a key early event in the pathogenesis of infection-associated preterm labor.