(A) Schematic diagram of the experimental design. At E12.5, pregnant mothers were injected with PBS or poly(l:C) to induce MIA. Two days later (E14.5), the pregnant mothers were treated with isotype or anti-IL-17a blocking antibodies. At P7~P9, pups were separated from the mothers to measure USV calls. At ~8wks, male offspring were subjected to the social approach test and marble burying test. (B) Ultrasonic vocalization (USV) assay. The number of pup calls is plotted on the y-axis (n = 17 (PBS + Cont), n = 17 (Poly(l:C) + Cont), n = 27 (Poly(l:C) + anti-IL-17a; from 3–4 independent dams per treatment). (C) Social approach behavior. Graphed as a social preference index (% time spent investigating social or inanimate stimulus out of total object investigation time) (n = 12 (PBS + Cont), n = 10 (Poly(l:C) + Cont), n = 17 (Poly(l:C) + anti-IL-17a; from 3–4 independent dams per treatment). (D) Marble burying behavior. Percentage of the number of buried marbles is plotted on the y-axis (n = 12 (PBS + Cont), n = 10 (Poly(l:C) + Cont), n = 17 (Poly(l:C) + anti-IL-17a; from 3–4 independent dams per treatment). (E) Total distance traveled during social approach behavior. (B, D and E) One-way ANOVA with Tukey post-hoc tests. (C) Two-way ANOVA with Tukey post-hoc test. **P < 0.01 and *P < 0.05. Graphs show mean ± SEM.