Influence of pediatric vaccines on amygdala growth and opioid ligand binding in rhesus macaque infants: A pilot study.

Author: Hewitson L, Lopresti BJ, Stott C, Mason NS, Tomko J.

Source: Acta Neurobiol Exp (Wars).

Year: 2010

Comment:

This primate study examines the impact of the vaccination schedule on the brain and notes, "In this pilot study, infant macaques receiving the recommended  pediatric vaccine regimen from the 1990’s displayed a different pattern of maturational changes in amygdala volume and differences in amygdala-binding of [11C]DPN following the MMR/DTaP/Hib vaccinations between T1 and T2 compared with non-exposed animals. There was also evidence of greater total brain volume in the exposed group prior to these vaccinations suggesting a possible effect of previous vaccinations to which these animals had been exposed."

Abstract / Excerpt:

"This longitudinal, case-control pilot study examined amygdala growth in rhesus macaque infants receiving the complete US childhood vaccine schedule (1994-1999). Longitudinal structural and functional neuroimaging was undertaken to examine central effects of the vaccine regimen on the developing brain. Vaccine-exposed and saline-injected control infants underwent MRI and PET imaging at approximately 4 and 6 months of age, representing two specific timeframes within the vaccination schedule. Volumetric analyses showed that exposed animals did not undergo the maturational changes over time in amygdala volume that was observed in unexposed animals. After controlling for left amygdala volume, the binding of the opioid antagonist [(11)C]diprenorphine (DPN) in exposed animals remained relatively constant over time, compared with unexposed animals, in which a significant decrease in [(11)C]DPN binding occurred. These results suggest that maturational changes in amygdala volume and the binding capacity of [(11)C]DPN in the amygdala was significantly altered in infant macaques receiving the vaccine schedule. The macaque infant is a relevant animal model in which to investigate specific environmental exposures and structural/functional neuroimaging during neurodevelopment."

Citation:

Hewitson L, Lopresti BJ, Stott C, Mason NS, Tomko J. Influence of pediatric vaccines on amygdala growth and opioid ligand binding in rhesus macaque infants: A pilot study. Acta Neurobiol Exp (Wars). 2010; 70(2):147-64.