Basic immunological toolbox for genus Peromsycus, infection tolerant reservoirs of zoonotic agents

Project Summary/Abstract
Peromyscus leucopus, the white-footed deermouse, is a natural host and major reservoir for the
agents of Lyme disease, anaplasmosis, and babesiosis among other zoonoses in North America.
The related species P. maniculatus is a reservoir for hantavirus as well as Lyme disease. While
mouse-like in appearance, these deermice are more closely related to hamsters and voles than to
Mus or Rattus. P. leucopus also has longevity 2-3 times that of the house mouse and has a more
restrained inflammatory response to TLR agonists and infection. While translational interest in
P. leucopus increases, including as a target for field vaccines and for genetic modification and then
environmental release, there are very limited tools besides genome-wide and targeted RNA-seq
for in-depth study of the immunology and host responses of these animals. Examples are reagents
and assays for flow cytometry and IgG subclasses. Antibodies for phenotyping white cells that are
developed for study of mice or humans seldom have sufficient cross-reactivity with deermouse
orthologous proteins to succeed. This application for a 2-year developmental project recognizes
this need for the field to advance and proposes to take the first steps to remedy the deficiency.
Using our access to a closed colony of P. leucopus that is representative of wild populations in
terms of genetic diversity, we will carry out work on the following specific aims:
Aim 1. Antibodies for phenotyping leukocytes of Peromyscus. First will be a pan-leukocyte
monoclonal antibody suitable for flow cytometry and sorting. The isolated leukocytes from
different outbred deermice will be subjected to multiplexed scRNA-seq, the results of which
provide either confirmation of provisional choices (i.e. CD14 and CD19) or guidance on
alternatives for marker antibodies of narrower specificity.
Aim 2. IgG subclasses of Peromyscus. Using the deduced amino acid sequences for constant
regions of heavy chains, we will characterize and measure subclasses by LC-MS/MS.
Discriminating peptides will be used for eliciting sub-class specific antibodies. The affinities of
different subclasses for Fc receptor ligands, like Protein A will be assessed.
Aim 3. Application of tools to models of systemic inflammation and of infection. The utility and
informativeness of the outcomes of Aims 1 and 2 will be assessed in our established P. leucopus
models of infection with B. burgdorferi or systemic inflammation from TLR agonists.

Grant Number: 1R21AI185311-01A1
NIH Institute/Center: NIH
Principal Investigator: Alan Barbour