D anti-CD28. This could infer that the exosomes carry with them information from the cells that secrete them, which can stimulate a proliferative response in resting T cells. It has previously been described that modified exosomes from APCs could induce a CD8+ T cell response in an antigenspecific manner [36]. Here we get a CD8+ T cell response probably not related to antigenic stimuli since the exosomes derive from autologous stimulated CD3+ T cells. When examining the level of cytokines and chemokines present in the supernatant from the T cell cultures, we note significant changes when exosomes are present. Exosomes together with IL-generate secretion of more cytokines and at higher levels than exosomes or IL-2 alone. The cytokine analysis also shows that T cells stimulated with IL-2 together with exosomes secrete CCL4. This chemokine is not present in IL-2 alone or exosome alone stimulated cells but is found in the supernatant from which the exosomes are derived. This may indicate that the exosomes carry information that together with IL-2 can induce resting T cells to respond similar to the cells that secreted them. The chemokine CCL4, also known as macrophage inflammatory protein 1b, has previously been shown to be secreted by CD8+ T cells [37?8] which supports the notion of a preferential stimulation of cytotoxic T cells as also indicated by the shift in CD4/CD8 ratio. The cytokine profile of cells stimulated with exosomes+IL-2 reveals a high level of IL-5 and IL-13, which may indicate a Th2 skewing of the 
activated cells [39]. In addition the exosomes seem to carry with them large amounts of CCL5 (RANTES), since the addition of exosomes to the culture media makes this cytokine immediately readily detectable (Fig. 3, 0 h). MedChemExpress 4 IBP Interestingly (-)-Calyculin A chemical information RANTES has been shown to be secreted by activated CD8+ T cells from a specific storage compartment with exosome properties [40] and exosomes carrying RANTES can actively inhibit HIV infection [25]. There is also a previous report demonstrating that RANTES is present in CD8+ cytotoxic cell granules and that it can act as a mitogen upon cell surface aggregation followed by secretion of MIP-1b [41]. These results correspond well with our observations. In summary, our result show that exosomes secreted from simulated CD3+ T cells can dramatically change the response of resting autologous T cells to IL-2. The exosomes carry RANTES and seem to favor a cytotoxic response, which could be of potential interest in anti-viral and anti-tumor treatment.AcknowledgmentsWe gratefully acknowledge Professor Johan Bergenholz and Dr. Moheb Nayeri at Chalmers technical university for the help with the Zetasizer Nano. We also thank Professor Kristina Eriksson and Professor Maria Bokarewa for their valuable help with comments about the manuscript. In addition we acknowledge IngaBritt and Arne Lundbergs forskningsstiftelse for the use of Beckman Optima L-100 XP and the FACSCantoII (Becton Dickinson).Author ContributionsConceived and designed the experiments: HV JW. Performed the experiments: JW TK PG HV. Analyzed the data: HV JW ET. Contributed reagents/materials/analysis tools: HV. Wrote the paper: JW ET HV PG TK.
During development, organisms must coordinate growth, proliferation and differentiation. The TORC1 complex is an evolutionarily conserved central node in coordination of cell growth by driving protein synthesis in response to growth factor signals and the availability of amino acids [1]. At the cellular level, i.D anti-CD28. This could infer that the exosomes carry with them information from the cells that secrete them, which can stimulate a proliferative response in resting T cells. It has previously been described that modified exosomes from APCs could induce a CD8+ T cell response in an antigenspecific manner [36]. Here we get a CD8+ T cell response probably not related to antigenic stimuli since the exosomes derive from autologous stimulated CD3+ T cells. When examining the level of cytokines and chemokines present in the supernatant from the T cell cultures, we note significant changes when exosomes are present. Exosomes together with IL-generate secretion of more cytokines and at higher levels than exosomes or IL-2 alone. The cytokine analysis also shows that T cells stimulated with IL-2 together with exosomes secrete CCL4. This chemokine is not present in IL-2 alone or exosome alone stimulated cells but is found in the supernatant from which the exosomes are derived. This may indicate that the exosomes carry information that together with IL-2 can induce resting T cells to respond similar to the cells that secreted them. The chemokine CCL4, also known as macrophage inflammatory protein 1b, has previously been shown to be secreted by CD8+ T cells [37?8] which supports the notion of a preferential stimulation of cytotoxic T cells as also indicated by the shift in CD4/CD8 ratio. The cytokine profile of cells stimulated with exosomes+IL-2 reveals a high level of IL-5 and IL-13, which may indicate a Th2 skewing of the activated cells [39]. In addition the exosomes seem to carry with them large amounts of CCL5 (RANTES), since the addition of exosomes to the culture media makes this cytokine immediately readily detectable (Fig. 3, 0 h). Interestingly RANTES has been shown to be secreted by activated CD8+ T cells from a specific storage compartment with exosome properties [40] and exosomes carrying RANTES can actively inhibit HIV infection [25]. There is also a previous report demonstrating that RANTES is present in CD8+ cytotoxic cell granules and that it can act as a mitogen upon 
cell surface aggregation followed by secretion of MIP-1b [41]. These results correspond well with our observations. In summary, our result show that exosomes secreted from simulated CD3+ T cells can dramatically change the response of resting autologous T cells to IL-2. The exosomes carry RANTES and seem to favor a cytotoxic response, which could be of potential interest in anti-viral and anti-tumor treatment.AcknowledgmentsWe gratefully acknowledge Professor Johan Bergenholz and Dr. Moheb Nayeri at Chalmers technical university for the help with the Zetasizer Nano. We also thank Professor Kristina Eriksson and Professor Maria Bokarewa for their valuable help with comments about the manuscript. In addition we acknowledge IngaBritt and Arne Lundbergs forskningsstiftelse for the use of Beckman Optima L-100 XP and the FACSCantoII (Becton Dickinson).Author ContributionsConceived and designed the experiments: HV JW. Performed the experiments: JW TK PG HV. Analyzed the data: HV JW ET. Contributed reagents/materials/analysis tools: HV. Wrote the paper: JW ET HV PG TK.
During development, organisms must coordinate growth, proliferation and differentiation. The TORC1 complex is an evolutionarily conserved central node in coordination of cell growth by driving protein synthesis in response to growth factor signals and the availability of amino acids [1]. At the cellular level, i.