SFARI

Inflammatory mechanisms have been implicated in autism. Treatments that modulate the immune system and inflammatory response, such as Trichuris suis ova (TSO), a parasitic worm called whipworm helminth, may be an experimental therapeutic option. Individuals with autism may have an increased immune response due to excess type 1 T-helper cells, which increases chronic inflammation. Individuals with autism may also have less of anti-inflammatory cytokines released by type 2 T-helper cells, which decreases chronic inflammation. It has been noted that some individuals with autism have improvements in behavioral symptoms when they have a fever, which further suggests that factors that influence the immune system and inflammation may have a role in autism etiology and potential treatments.

There is growing support for the idea that both genetic and environmental risk factors contribute to autism. One environmental risk is maternal infection, as validated by large epidemiological studies showing links between infection during pregnancy and autism in the child. Similar associations were found with elevated immune responses in maternal serum or amniotic fluid. Also consistent with an immune pathophysiology are findings of activated microglia — immune cells within the brain — in people with autism, as well as dysregulation of immune-related genes in the brain, cerebral spinal fluid and periphery.

Crabtree and Gleeson will focus on rare high-impact genetic mutations for factors in the BAF complex to test how links between neuronal activity and the epigenome may be interrupted in ASD.

Rebecca Saxe will test whether midbrain dopaminergic signals of social cravings, previously observed in mice, are similarly observed in humans. As impairments in social motivation have been postulated to be a core social deficit in autism spectrum disorder (ASD), these results will improve the value of the mouse model for testing mechanisms of altered social motivation in ASD.

SFARI is helping to make mouse models of high-risk autism genes and copy number variants available to the research community.

Clinical Research Associates, L.L.C., an affiliate of the Simons Foundation, has recently launched a randomized controlled trial to test the safety, tolerability and efficacy of arbaclofen in 16p11.2 BP4-BP5 deletion syndrome.

Because of the coronavirus pandemic, SFARI ran the fall 2020 science meeting virtually in a series of six weekly webinars, beginning on October 2, 2020. SFARI investigators presented their latest findings in autism research, ranging from autism genetics, through molecular mechanisms and neural circuits, to clinical insights.

A number of studies have lead to the suggestion that disruptions to chloride homeostasis play a role in a variety of neurological and neurodevelopmental disorders. The neuron-specific potassium chloride co-transporter, KCC2, is the major chloride exporter in neuronal cells, and mutations in SLC12A5 (the gene encoding KCC2) have been reported in individuals with some neurodevelopmental disorders, such as autism spectrum disorder (ASD), epilepsy and schizophrenia. Further, results from KCC2 knockout and knockdown mice highlight the importance of this protein in proper neuronal function.

Genetic studies of ASD implicate alterations in synaptic development and signaling, with the synaptic protein neurexin-1 playing a pivotal role. Ann Marie Craig aims to develop new approaches to overcome neurexin-1-linked synaptic deficits in ASD by modulating the remaining NRXN1 allele to boost neurexin-1 function and restore synaptic structure and function.