The nuocyte is a cell of the innate immune system that plays an important role in type 2 immune responses that are induced in response to helminth worm infection or in conditions such as asthma and atopic disease.[1] Nuocytes are amongst the first cells activated in type 2 immune responses and are thought to play important roles in activating and recruiting other cells types through their production of type 2 cytokinesinterleukin 4, 5 and 13.[1] Nuocytes have been observed to proliferate in the presence of interleukin 7 (IL-7) in vitro.[2] Nuocytes contribute to the expulsion of helminth worms [1] and to the pathology of colitis[3] and allergic airways disease.[4]
The nuocyte was identified at the same time as several other immune cells that play similar roles in type 2 immunity. These include Natural Helper Cells (NHCs),[5] Innate Helper 2 (Ih2) cells [6] and multi-potent progenitor (MPP) type 2 cells.[7] The exact relationship between these cell types remains contentious [8][9] but all share a type-2-inducing phenotype. MPP type 2 cells appear to differ from the other populations in that they have a myeloid, rather than lymphoid, origin.[7]
Nuocytes have been shown to have a lymphoid origin and a developmental pathway that is dependent upon the transcription factor RORα and Notch signalling.[10] Pro-T cell progenitors retain nuocyte developmental potential but, unlike T cells, the thymus is dispensable for their development.
^Mirchandani, A; Salmond, R; Liew, F (2012). "Interleukin-33 and the function of innate lymphoid cells". Trends in Immunology. 33 (8): 389–396. doi:10.1016/j.it.2012.04.005. PMID22609147.
^Neill, DR; McKenzie, AN (May 2011). "Nuocytes and beyond: new insights into helminth expulsion". Trends in Parasitology. 27 (5): 214–21. doi:10.1016/j.pt.2011.01.001. PMID21292555.
^Saenz, SA; Noti, M; Artis, D (Nov 2010). "Innate immune cell populations function as initiators and effectors in Th2 cytokine responses". Trends in Immunology. 31 (11): 407–13. doi:10.1016/j.it.2010.09.001. PMID20951092.