Are there common triggers of preterm deliveries?
Coitus during the last few weeks of pregnancy appears to increase the risk of preterm delivery, while a possible detrimental effect of physical exertion seems more limited. Stressful events should not receive undue attention as possible causes of preterm delivery.
Our results seem to be a reflection of the unique properties of the 242B58 Ab, which does not antagonize B7 binding to CTLA-4 and affect its ability to out-compete CD28 for B7 binding. It does, however, seem to interfere with CTLA-4 signaling, suggesting that competition for B7 may be important in induction of tolerance, but signaling through CTLA-4 is more important in maintaining a tolerant phenotype.