Autism Spectrum Disorder: From molecular level to development

Autism spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communication and behavioral alterations. The ASD trigger is a complex interplay of both genetic and environmental risk factors, involving immune alterations and synaptic connection deficiency in early life. Since the first descriptions of autism in 1943-44, 70 years of investigation have passed, with great efforts mainly in the last decade, bringing important information related to the ASD. Nevertheless, even with these advances, the etiology of ASD remains largely unknown and we are still searching for specific clinical marker(s) able to improve early diagnosis. Also we are experiencing an increase in prevalence of ASD that can be attributed to advances in the knowledge of the symptoms and improvement in diagnostic criteria, but also due to environmental risk factors which may be related to changes in lifestyle of the society (drugs, pollutants, stress, etc.), especially during pregnancy. In any case, this high prevalence indicates that the subject requires emergency measures due to the high economic, social and family cost. We work on the hypothesis that an integrated maternal-embryo systems can contribute to the understanding of ASD. One possibility concerns neuroimmune interactions during ASD development. The presence of environmental risk factors during critical periods of embryonic/fetal development may influence the immune system in the mother, promoting localized or systemic inflammatory responses with the release of cytokines and hormonal molecules, which in turn, via neuroimmunomodulatory responses and crosstalk between circulatory and neural systems, may impair circuitry, plasticity and neuron-glial function in the embryo/fetus. In this context, the understanding of the neuroimmune changes that may underlie the pathophysiology of this disorder during development can have a large impact on the search for new clinical and therapeutic strategies to improve the quality of life of the individual with ASD.