Characterization of innate lymphoid cells in a non-mammalian host
Innate lymphoid cells (ILCs) are a relative new group of innate lymphocytes that have been extensively described in both mice and human. ILCs are highly abundant at mucosal sites where they have a diverse set of functions. ILCs can promote host defense against infections, regulate interactions with microbiota and aid in tissue healing and repair. In contrast, ILCs are also able to promote inflammation and tumor progression.1
ILCs lack expression of cell surface markers present on common hematopoietic cell lineages, antigen specific B and T cell receptors and they do not undergo clonal selection and expansion after stimulation. Interestingly, ILCs do mirror phenotypes and functions of T cells and may represent the innate counterparts of T helper cells (Th)2.
The family of ILCs is divided in three subgroups based on transcription factors controlling their development and their secretion of cytokines, namely ILC1, ILC2 and ILC3. The ILC1 group expresses the transcription factor T-bet and secretes Th type 1 cell‐associated cytokines such as IFNγ and TNFα. In addition, natural killer (NK) cells are part of the ILC1 group. The ILC2 group expresses GATA-3 as main transcription factor and secretes IL‐4 and IL‐5, which are Th type 2 associated cytokines. The ILC3 group expresses transcription factor RORγt and secretes cytokines IL-17A and IL-22, which are also secreted by Th17 and Th22 cells at mucosal barriers.3 In contrast to an abundance of literature on ILCs in human and mice, knowledge on ILCs in veterinary species such as cattle, swine and chickens is limited. NK cells and ILCs are part of the innate immune system, which is important during the first two to three weeks in chickens as the adaptive system is not fully matured yet. We hypothesize that ILCs are also present in chickens as they have profound functions in immunity. More knowledge on ILCs will enhance our understanding of the innate immune responses upon infections.
Research question
Can innate lymphoid cells be identified in chickens?
Experimental approach and anticipated results
ILCs will be isolated from the intestine of chickens. These cells will be characterized using chicken specific markers which resemble ILC markers used in humans, and subsequently analysed by flow cytometry. After staining the chicken ILCs, the different ILC groups will be sorted to collect cells for RNA analysis/qPCR. In this way, phenotype and functional aspects (such as expression of cytokine profiles) of each ILC group will be investigated.
Techniques
Flow cytometry, cell sorting, quantitative PCR (qPCR)
Contact
Nathalie Meijerink (n.meijerink@uu.nl, tel: +31 30 253 5836)
References
1. Artis D, Spits H. The biology of innate lymphoid cells. Nature. 2015;517(7534):293-301. Accessed 27 March 2019. doi: 10.1038/nature14189.
2. Eberl G, Colonna M, Santo JPD, McKenzie ANJ. Innate lymphoid cells: A new paradigm in immunology. Science. 2015;348(6237). Accessed 15 March 2019. doi: 10.1126/science.aaa6566.
3. Withers DR. Innate lymphoid cell regulation of adaptive immunity. Immunology. 2016;149(2):123-130. Accessed 15 March 2019. doi: 10.1111/imm.12639.