Modulation of anti-tumor lymphocyte function by neurotransmitter glutamate ========================================================================== * Thomas Hodo * Menaka Thounaojam * Anil Shanker * Multiple Sclerosis * Glutamate * Glutamate Receptor * Receptor AMPA * Neurotransmitter Glutamate Meeting abstracts Most research to date pertaining to neural influence on immune response involves immunosuppression via the anti-inflammatory pathway. However, there is emerging evidence indicating that neurotransmitters have the ability to promote immune activation. We are investigating whether neurotransmitters can modulate and/or activate T cell function in situations where immunosuppression is prevalent such as in the tumor microenvironment. Published work suggests that glutamate, serotonin, dopamine, and Substance P trigger immune responses such as cytokine secretion, integrin expression, and chemotaxis. We saw that both CD4 and CD8 T cells express high surface protein levels of glutamate receptor AMPA iGluR3, which is able to import Ca2+ and Na+. We also found that mGluR1 is significantly upregulated on lymphocytes upon activation. Our data further show that T cells in the tumor-draining LN and tumor-infiltrating lymphocytes have upregulated expression of iGluR3 and mGluR1. Treatment with glutamate or its receptor agonist augmented T cell proliferation following CD3-CD28-mediated TCR stimulation. Thus, modulation of glutamate receptor signaling can be useful for enhancing anti-tumor T cell immunity such as inhibition of AICD, enhancement of proliferation, and increased cytokine production [1, 2]. Indeed, overactivation of lymphocytes in multiple sclerosis is closely tied to the overexpression of AMPA GluR3 on T cells [3]. Experiments are under way to dissect in an adoptive transfer set up whether glutamate-modulated immune effector function involves specific activation of anti-tumor lymphocytes to elicit cytolytic response that is needed to cause tumor cell death. Our findings will help identify novel neuro-immune modulators that may serve to enhance anti-tumor T cell response. * © The Author(s). 2014 ## References 1. 1.Chiocchetti A, Miglio G, Mesturini R, Varsaldi F, Mocellin M, Orilieri E, Dianzani C, Fantozzi R, Dianzani U, Lombardi G. Group I mGlu receptor stimulation inhibits activation-induced cell death of human T lymphocytes. British journal of pharmacology. 2006;148:760–768. pmcid:1617076 [doi:10.1038/sj.bjp.0706746](http://dx.doi.org/10.1038/sj.bjp.0706746) [CrossRef](http://jitc.bmj.com/lookup/external-ref?access_num=10.1038/sj.bjp.0706746&link_type=DOI) [PubMed](http://jitc.bmj.com/lookup/external-ref?access_num=16751798&link_type=MED&atom=%2Fjitc%2F2%2FSuppl_3%2FP38.atom) 2. 2.Pacheco R, Oliva H, Martinez-Navio JM, Climent N, Ciruela F, Gatell JM, Gallart T, Mallol J, Lluis C, Franco R. Glutamate released by dendritic cells as a novel modulator of T cell activation. J Immunol. 2006;177:6695–6704. [doi:10.4049/jimmunol.177.10.6695](http://dx.doi.org/10.4049/jimmunol.177.10.6695) [Abstract/FREE Full Text](http://jitc.bmj.com/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6ODoiamltbXVub2wiO3M6NToicmVzaWQiO3M6MTE6IjE3Ny8xMC82Njk1IjtzOjQ6ImF0b20iO3M6MjQ6Ii9qaXRjLzIvU3VwcGxfMy9QMzguYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 3. 3.Sarchielli P, Di Filippo M, Candeliere A, Chiasserini D, Mattioni A, Tenaglia S, Bonucci M, Calabresi P. Expression of ionotropic glutamate receptor GLUR3 and effects of glutamate on MBP- and MOG-specific lymphocyte activation and chemotactic migration in multiple sclerosis patients. Journal of neuroimmunology. 2007;188:146–158. [doi:10.1016/j.jneuroim.2007.05.021](http://dx.doi.org/10.1016/j.jneuroim.2007.05.021) [CrossRef](http://jitc.bmj.com/lookup/external-ref?access_num=10.1016/j.jneuroim.2007.05.021&link_type=DOI) [PubMed](http://jitc.bmj.com/lookup/external-ref?access_num=17628700&link_type=MED&atom=%2Fjitc%2F2%2FSuppl_3%2FP38.atom)