Investigating the relationship between soil microbiome diversity and immune function in deer mice

Abstract

Soil microbiota impact every aspect of the Western deer mouse (Peromyscus sonoriensis) diet, including plants and arthropods as major food sources. Diet has been shown to influence immune function in similar species such as Mus musculus; however, research has not examined underlying factors such as soil microbial diversity, particularly in a wild setting. We employed a field-based approach to investigate the relationship between immune function and soil microbiome among a variety of urban and rural habitats in Spokane, Washington. Deer mice were live-trapped across 14 different sites during May 2025. White blood cell counts were estimated for 88 individual blood samples via hemacytometer. Soil samples were collected from each field site in triplicate, and 16S profiling was performed with Nanopore sequencing for diversity analyses. While Shannon diversity differed significantly between urban and rural soil samples, no direct correlation was found between soil microbiome diversity and deer mouse white blood cell counts. Ongoing analysis is investigating effects of intermediate factors linking soil microbial diversity with immune effects, such as arthropod diversity or mouse gut microbiome diversity. This study provides a better understanding of the complex relationship between wildlife health and urbanization-related dietary impacts, using the Western deer mouse as a model organism for translation to other mammalian populations.