Singer's work explores the mechanisms with which a body identifies what is self and what is not self. At a time when many researchers understood that T cells recognize self through identification of the major histocompatibility complex (MHC) it was not understood how T cells acquire that capability. Using a unique approach to thymus transplantation, Singer showed that it is the thymus that educates self-recognition specificity in T cells.[3] A series of later studies in Singer's lab demonstrated that the property of self-recognition in T cells is acquired during development in the thymus rather than predetermined prior to development or genetically encoded in the genome.[4]
Singer A, Hathcock KS, Hodes RJ: Self recognition in allogeneic thymic chimeras. Self recognition by T helper cells from thymus-engrafted nude mice is restricted to the thymic H-2 haplotype. The Journal of Experimental Medicine. 155 (1): 339–344, 1982[3]
Mu J, Tai X, Iyer SS, Wiessman JD, Singer A, Singer DS: Regulation of MHC class I expression by Foxp3 and its effect on regulatory T cell function. Journal of Immunology. 192: 2892–903, 2014.[5]
Tai X, Erman B, Alag A, Mu J, Kimura M, Katz G, Guinter T, McCaughtry T, Etzensperger R, Feigenbaum L, Singer DS, Singer A: Foxp3 transcription factor is proapoptotic and lethal to developing regulatory T cells unless counterbalanced by cytokine survival signals. Immunity. 38: 1116–28, 2013.[6]
Kimura MY, Pobezinsky LA, Guinter TI, Thomas J, Adams A, Park JH, Tai X, Singer A: IL-7 signaling must be intermittent, not continuous, during CD8+ T cell homeostasis to promote cell survival instead of cell death. Nature Immunology. 14: 143–51, 2013.[7]
Van Laethem F, Tikhonova AN, Pobezinsky LA, Tai X, Kimura MY, Le Saout C, Guinter TI, Adams A, Sharrow SO, Bernhardt G, Feigenbaum L, Singer A: Lck availability during thymic selection determines the recognition specificity of the T cell repertoire. Cell. 154: 1326–41, 2013.[4]
SInger A, Adoro S, Park JH: Lineage fate and intense debate: myths, models and mechanisms of CD4- versus CD8-lineage choice. Nature Reviews Immunology. 2008 Oct; 8(10): 788–801. doi 10.1038/nri2416.[8]