Investigation of Vocalization and Play Behavior in Juvenile Offspring of Maternal Immune Activated Female Mice

Background: Activation of the maternal immune system is associated with an increased risk for autism and schizophrenia. While animal models have increasingly been used to investigate the behavioral and biological consequences of maternal immune activation in adult offspring, few findings have demonstrated alterations in juvenile behaviors. Moreover, differences in genetic background may confer increased sensitivity to the developmental effects of maternal immune activation. Therefore it is important to consider how various mouse strains may respond uniquely to the effects of maternal immune activation

Objectives: Investigate whether maternal immune activation alters ultrasonic vocalizations and juvenile play behavior in offspring of two mouse strains.

Methods: Pregnant female mice were exposed to a single injection of polyinosinic-polycytidylic acid [Poly(I:C)], or vehicle control, on gestational day 12.5 and offspring were measured for differences in ultrasonic vocalizations and juvenile play behaviors

Results: Offspring of females exposed to Poly(I:C) exhibited increased frequency of vocalizations on postnatal day 10 of development. Interestingly, pups from immune activated females displayed alterations in social interaction during juvenile play with a novel mouse.  

Conclusions: Maternal immune activation on gestational day 12.5 results in altered patterns of ultrasonic vocalizations and juvenile interactions in offspring. These findings support the link between maternal infection and increased prevalence of autism.