Effects of Prenatal Administration of Tetanus Toxoid on the Sociability and Explorative Behaviors of Rat Offspring: A Preliminary Study
Eda Sünnetçi *, Ferit Durankuş , Yakup Albayrak , Mümin Alper Erdoğan , Özüm Atasoy , Oytun Erbaş
1Istanbul Training and Education Hospital, Department of Pediatrics, İstanbul,Turkey, 2Istanbul Medeniyet University, Department of Pediatrics, İstanbul,Turkey, 3Tekirdağ Namık Kemal University, Faculty of Medicine, Department of Psychiatry, Tekirdağ, Turkey, 4Katip Çelebi University Medical School, Department of Physiology, İzmir Turkey, 5Kartal Education and Research Hospital, Department of Radiation Oncolgy, İstanbul, Turkey, 6Demiroğlu Bilim University Medical School, Department of Physiology, İstanbul, Turkey
Received: March 9, 2020; Revised: June 24, 2020; Accepted: June 24, 2020; Published online: June 24, 2020.
© The Korean College of Neuropsychopharmacology. All rights reserved.

Objective: Autism spectrum disorder (ASD) is a severely disabling psychiatric disease characterized by impairments in communication and social skills. Although efforts have been made to explore the etiology of ASD, its pathophysiology remains unclear. This issue is rendered more challenging by confounding data about the effects of vaccination on disease etiology. In this study, therefore, we investigated the neurodevelopmental effects of maternal tetanus toxoid administration on rat offspring. We hypothesized that the vaccine affects the sociability and preference for social novelty of rat offspring as well as the production of immunological and neurotrophic factors, including tumor necrosis factor alfa (TNFα), neuregulin-1 (NRG-1), neuron growth factor (NGF), and oxytocin.
Methods: The study involved 12 female and four male adult Sprague Dawley rats (238 ± 10 g), which were assigned to two groups. Group 1 (control group) was given 0.5 mL of normal saline (0.9% NaCl) on the 10th day of pregnancy, whereas group 2 (experimental group) was administered 0.5 mL of tetanus vaccine (tetanus toxoid, 40 IU).
Results: Maternal tetanus toxoid administration exerted beneficial effects on the sociability and explorative behaviors of the rats. The brain tissue levels of TNFα, NGF, NRG-1, and oxytocin were higher in the experimental group than among the controls.
Conclusion: This study is the first to demonstrate the advantages of tetanus toxoid administration in relation to the sociability and explorative behaviors of rat offspring. The results showed that the vaccine also influences NRG-1, neuregulin, and oxytocin production.
Keywords: autism, vaccination, tetanus, neuroinflammation, neurogenesis