Abstract
Severe infections during pregnancy are one of the major risk factors for cognitive brain impairment in offspring. It has been suggested that maternal inflammation leads to dysfunction of cortical GABAergic interneurons that in turn underlies cognitive impairment of the affected offspring. However, the evidence comes largely from studies of adult or mature brain and how impairment of inhibitory circuits arises upon maternal inflammation is unknown. Here we show that maternal inflammation affects multiple steps of cortical GABAergic interneuron development, i.e. proliferation of precursor cells, migration and positioning of neuroblasts as well as neuronal maturation. Importantly, the development of distinct subtypes of cortical GABAergic interneurons was discretely impaired as a result of maternal inflammation. This translated into a reduction in cell numbers and redistribution across cortical regions and layers. Furthermore, vulnerability of GABAergic interneuron subtypes was associated with varying impact of maternal inflammation on interneuron precursor pools that depends on the stage of brain development. Thus, differential effect of maternal inflammation on GABAergic interneuron subtypes and the time of insult might be key factors contributing to etiology of cognitive impairment in maternal inflammation-affected offspring.