Work Package 8
Elucidating chicken γδ T cell functions and ligands via genetically engineered chicken models
γδ T cells play a critical role in the immune system of mammals, responding to diverse antigens, including CD1 and butyrophilin molecules. In chickens, however, the functions of γδ T cells and their ligands remain poorly understood. Our project aims to unravel the role of potential chicken γδ T cell ligands—CD1, butyrophilin, and BG molecules—in immune responses to pathogens and vaccines.
We hypothesize that these molecules are essential for γδ T cell function in chickens, either by recognizing pathogen molecules (e.g., Salmonella lipids presented by CD1) or influencing mucosal integrity (mediated by butyrophilin or BG molecules). To test this hypothesis, we will employ state-of-the-art biochemical and genetic approaches, including CRISPR/Cas9-mediated gene knockouts, to evaluate the role of these ligands in vivo.
Aim 1: Investigating CD1 Molecules
We will produce CD1 multimers and assess their ability to bind γδ T cells. Using CRISPR/Cas9, we will generate chickens lacking CD1 genes and evaluate phenotypic changes, alterations in γδ T cell populations, and immune responses to key pathogens and vaccines, including MDV, IBDV, AIV, and Salmonella.
Aim 2: Elucidating Butyrophilin Molecules
We will study two chicken butyrophilin genes, one located near the MHC and the other outside it. Multimers of these molecules will be tested for γδ T cell binding. Gene knockouts will be performed to determine the effects on receptor expression, γδ T cell repertoires, and immune responses to pathogens and vaccines.
Aim 3: Assessing BG Molecules
We will investigate BG molecules as potential γδ T cell ligands by producing homo- and heterodimers and testing their interaction with γδ T cells. Knockouts of the BG1 gene or the entire BG locus will help assess their role in immune regulation, γδ T cell functionality, and vaccine-induced immunity.
This study will not only shed light on the fundamental biology of chicken γδ T cells but also provide insights into immune responses in vertebrates. By addressing critical knowledge gaps, our research may pave the way for improved vaccine strategies and disease control in poultry.
Principal investigator:
Prof. Dr. med. vet. Benjamin Schusser
PhD-student:
tba