Two studies published this month in the Journal of Neuroinflammation found that children with autism have altered regulatory T cells, immune components that act as "brakes" on inflammation, compared to typically developing children. In an animal model, Treg therapy reduced neuroinflammation, changed gene expression in brain regions tied to autism, and improved social and behavioral outcomes.

The research comes from the UC Davis MIND Institute and was led by Professor Paul Ashwood. It's one of the first studies to test whether increasing regulatory T cells (Tregs) can address both immune dysfunction and behavioral challenges in autism.

What the Studies Found

The first study characterized Tregs in 36 children with autism and 18 typically developing children. Researchers found that autistic children had altered Tregs both in number and in the genes those cells express.

Children with fewer Tregs showed more challenging behaviors. The study also identified distinct Treg patterns in autistic children with gastrointestinal problems compared to those without GI symptoms.

In the second study, researchers used a maternal immune activation (MIA) mouse model, in which offspring exhibit autism-like behaviors. They transferred Tregs from healthy mice into MIA offspring and examined tissues commonly affected in autism: blood, brain, and gut.

Male mice showed the most significant improvements after Treg treatment. Changes included increased helpful Treg cells, reduced pro-inflammatory cells in the spleen and gut, fewer inflammatory cytokines, and altered gene expression in the cerebellum, frontal cortex, and hippocampus. Males also showed behavioral improvements in self-grooming and socializing.

"These results suggest that Treg therapy could be a promising approach for reducing inflammation and related impacts in conditions linked to maternal immune activation and neurodevelopmental conditions such as autism," Ashwood said in a statement.

Why This Matters

Regulatory T cells act as the immune system's calming force. When they're reduced or dysfunctional, the body's inflammatory response becomes overactive. This study connects that immune imbalance to behavioral traits and GI issues that many autistic children experience.

The link between Tregs and gastrointestinal symptoms is notable. Many families report that behavioral challenges worsen when GI problems flare. This research suggests a shared immune mechanism may drive both.

The animal model results show that targeting Tregs changed not just immune markers but also gene expression in brain regions involved in social behavior, sensory processing, and motor control. That's a biological pathway, not just symptom management.

What This Means for Families

Treg therapy isn't available for children with autism yet, and it may be years before clinical trials begin. This is early-stage research.

But it represents a different research direction. Most autism interventions target behavior or development. This approach addresses a biological mechanism (immune dysfunction) that may contribute to both behavioral and physical symptoms.

If future studies confirm these findings in humans, Treg-based therapies could offer a treatment option for autistic individuals with documented immune dysregulation or chronic inflammation.

The Timing

This research arrives at a moment when federal autism research funding is shrinking. The National Institutes of Health announced cuts to autism-related grants in early 2026, and several research programs at university centers have scaled back.

The UC Davis MIND Institute has historically relied on a mix of federal, state, and private funding. The studies published this month were supported in part by private foundations and institutional funds.

What Families Can Do Now

• If your child has autism and chronic GI symptoms, discuss immune function with your child's doctor. Ask whether immune markers have been assessed.
• Monitor for clinical trial announcements from the UC Davis MIND Institute or other autism research centers. Trials testing Treg-related therapies may begin within the next few years.
• Understand that this research doesn't suggest that autism is caused by immune dysfunction alone. It identifies one biological pathway that may contribute to symptoms in some individuals.
• Keep managing existing symptoms with current evidence-based interventions. This research doesn't replace therapies that work now.

The full text of both studies is available on the Journal of Neuroinflammation website. The UC Davis MIND Institute maintains a research updates page for families interested in following this work.