Abstract
Regulatory T cells (Tregs) play crucial role in maintenance of peripheral tolerance. Recent clinical trials confirmed safety and efficacy of Treg treatment of deleterious immune responses. However, Tregs lose their characteristic phenotype and suppressive potential during expansion ex vivo. Therefore, multiple research teams have been studding Treg biology in aim to improve their stability in vitro. In the current paper, we demonstrate that mild hypothermia of 33 °C induces robust proliferation of Tregs, preserves expression of FoxP3, CD25 and Helios, and prevents TSDR methylation during culture in vitro. Tregs expanded at 33 °C have stronger immunosuppressive potential and remarkably anti-inflammatory phenotype demonstrated by the whole transcriptome sequencing. These observations shed new light on impact of temperature on regulation of immune response. We show that just a simple change in temperature can preserve Treg stability, function and accelerate their proliferation, responding to unanswered question- how to preserve Treg stability in vitro.
Highlights
Thymus derived, natural regulatory T cells (Tregs) constitute ≈1% of lymphocytes in peripheral blood, but they play a crucial role in maintenance of peripheral tolerance[1,2]
Temperature of 33 °C induces robust proliferation of Tregs. 14-day culture of Tregs at 33 °C resulted in 4.5-fold higher cell counts as compared with Tregs expanded at 37 °C
Analysis of size and granularity of Tregs expanded at 37 and 33 °C showed that cells cultured at mild hypothermia were slightly bigger and more granular at each time-point, than Tregs expanded at standard culture temperature
Summary
Natural regulatory T cells (Tregs) constitute ≈1% of lymphocytes in peripheral blood, but they play a crucial role in maintenance of peripheral tolerance[1,2]. For clinical purposes Tregs are used to be expanded for up to 14 days in presence of IL-2 and magnetic beads coated with anti-CD3 and anti-CD28 antibodies (Ab)[5,6,7,9,15] Even in these established culture conditions and in the same laboratory, the fold increase of Treg number may vary between the expansions from several to nearly 50 times[9,15]. Recent studies confirm that the drug preferentially inhibits proliferation of conventional T cells that can contaminate Treg culture[18], but does not prevent loss of FoxP3 expression in natural Tregs during the second week of expansion[13,19]. 5-10-fold reduction in Treg proliferation in presence of rapamycin was reported[16]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
