# IL-6 Inhibition Partially Ameliorates Maternal Immune Activation-Induced Autism-Like Behavioral Abnormalities in Mice

## TL;DR

This study shows that blocking IL-6 can reduce some autism-like behaviors in mice caused by maternal immune activation during pregnancy.

## Contribution

The study demonstrates that IL-6 inhibition partially reverses social and anxiety-related behavioral deficits in a mouse model of maternal immune activation.

## Key findings

- IL-6 inhibition reduced anxiety-like behaviors in MIA offspring.
- Social interaction deficits were partially restored by IL-6 inhibition.
- Core ASD-like features like social preference and repetitive behaviors remained unaffected.

## Abstract

Prenatal maternal immune activation (MIA) has been implicated in autism spectrum disorder (ASD) pathogenesis, with interleukin-6 (IL-6) identified as a key inflammatory mediator. We investigated the therapeutic potential of IL-6 inhibition in an MIA mouse model induced by Toxoplasma gondii soluble tachyzoite antigen (STAg). Adult MIA offspring received systemic administration of the IL-6-neutralizing antibody (MP5-20F3) or isotype control, followed by behavioral assessments one week later. Open field and elevated plus maze tests revealed heightened anxiety-like behaviors in the STAg offspring, which were largely reversed by IL-6 inhibition. Reciprocal social interaction tests showed diminished sociability in the STAg offspring, which was partially restored by IL-6 inhibition. However, core ASD-like features, including impaired social preference and recognition in the three-chamber test, as well as increased repetitive behaviors, remained resistant to IL-6 inhibition. These findings demonstrate that STAg-induced MIA elicits anxiety-like and ASD-like phenotypes in adult offspring, with IL-6 playing an important role in anxiety-like behaviors and social interaction deficits. Systemic IL-6 inhibition partially ameliorates behavioral abnormalities. This study suggests that IL-6-targeted therapies may address a subset of ASD-related symptoms, and comprehensive strategies are needed for broader efficacy.