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 cytokines interleukin 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.
Neill, DR; Wong, SH; Bellosi, A; Flynn, RJ; Daly, M; Langford, TK; Bucks, C; Kane, CM; Fallon, PG; Pannell, R; Jolin, HE; McKenzie, AN (2010). "Nuocytes represent a new innate effector leukocyte that mediates type-2 immunity". Nature. 464 (7293): 1367–70. Bibcode:2010Natur.464.1367N. doi:10.1038/nature08900. PMC 2862165. PMID 20200518. Camelo, A; Barlow, JL; Drynan, LF; Neill, DR; Ballantyne, SJ; Wong, SH; Pannell, R; Gao, W; Wrigley, K; Sprenkle, J; McKenzie, AN (2012-04-27). "Blocking IL-25 signalling protects against gut inflammation in a type-2 model of colitis by suppressing nuocyte and NKT derived IL-13". Journal of Gastroenterology. 47 (11): 1198–211. doi:10.1007/s00535-012-0591-2. PMC 3501170. PMID 22539101. Barlow, JL; Bellosi, A; Hardman, CS; Drynan, LF; Wong, SH; Cruickshank, JP; McKenzie, AN (Jan 2012). "Innate IL-13-producing nuocytes arise during allergic lung inflammation and contribute to airways hyperreactivity". The Journal of Allergy and Clinical Immunology. 129 (1): 191–8.e1–4. doi:10.1016/j.jaci.2011.09.041. PMID 22079492. Moro, K; Yamada, T; Tanabe, M; Takeuchi, T; Ikawa, T; Kawamoto, H; Furusawa, J; Ohtani, M; Fujii, H; Koyasu, S (2010-01-28). "Innate production of T(H)2 cytokines by adipose tissue-associated c-Kit(+)Sca-1(+) lymphoid cells". Nature. 463 (7280): 540–4. doi:10.1038/nature08636. PMID 20023630. S2CID 4420895. Saenz, SA; Siracusa, MC; Perrigoue, JG; Spencer, SP; Urban JF Jr; Tocker, JE; Budelsky, AL; Kleinschek, MA; Kastelein, RA; Kambayashi, T; Bhandoola, A; Artis, D (2010-04-29). "IL25 elicits a multipotent progenitor cell population that promotes T(H)2 cytokine responses". Nature. 464 (7293): 1362–6. Bibcode:2010Natur.464.1362S. doi:10.1038/nature08901. PMC 2861732. PMID 20200520. 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. PMID 20951092. Wong, SH; Walker, JA; Jolin, HE; Drynan, LF; Hams, E; Camelo, A; Barlow, JL; Neill, DR; Panova, V; Koch, U; Radtke, F; Hardman, CS; Hwang, YY; Fallon, PG; McKenzie, AN (2012-01-22). "Transcription factor RORα is critical for nuocyte development". Nature Immunology. 13 (3): 229–36. doi:10.1038/ni.2208. PMC 3343633. PMID 22267218.
