Journal of Molecular Medicine

, Volume 88, Issue 6, pp 577–588

Reciprocal granzyme/perforin-mediated death of human regulatory and responder T cells is regulated by interleukin-2 (IL-2)

  • Malgorzata Czystowska
  • Laura Strauss
  • Christoph Bergmann
  • Marta Szajnik
  • Hannah Rabinowich
  • Theresa L. Whiteside
Original article

DOI: 10.1007/s00109-010-0602-9

Cite this article as:
Czystowska, M., Strauss, L., Bergmann, C. et al. J Mol Med (2010) 88: 577. doi:10.1007/s00109-010-0602-9
  • 161 Downloads

Abstract

Human CD4+CD25highFOXP3+ T regulatory cells (Treg) can suppress responder T cell (RC) functions by various mechanisms. In co-cultures of Treg and autologous activated RC, both cell subsets up-regulate the expression of granzymes and perforin, which might contribute to Treg-mediated suppression. Here, we investigate the sensitivity and resistance of Treg and RC to granzyme/perforin-mediated death. CD4+CD25neg RC were single cell-sorted from the peripheral blood of 25 cancer patients and 15 normal controls. These RC were carboxyfluorescein diacetate succinimidyl ester (CFSE) labeled and co-cultured with autologous CD4+CD25highFOXP3+ Treg ± 150 or ±1,000 IU/mL of interleukin-2 (IL-2) to evaluate suppression of RC proliferation. In addition, survival of the cells co-cultured for 24 h and 5 days was measured using a flow-based cytotoxicity assay. Freshly isolated Treg and RC expressed granzyme A (GrA), granzyme B (GrB), and perforin. Percentages of positive cells were higher in cancer patients than controls (p < 0.01) and increased upon OKT3 and IL-2 stimulation. Treg, co-cultured with RC at 150 IU/mL of IL-2, no longer expressed cytotoxins and became susceptible to RC-mediated, granzyme/perforin-dependent death. However, in co-cultures with 1,000 IU/mL of IL-2, Treg became resistant to apoptosis and induced GrB-dependent, perforin-independent death of RC. When the GrB inhibitor I or GrB-specific and GrA-specific small inhibitory ribonucleic acids were used to block the granzyme pathway in Treg, RC death, and Treg-mediated suppression of RC, proliferation were significantly inhibited. Human CD4+CD25high Treg and CD4+CD25neg RC reciprocally regulate death/growth arrest by differentially utilizing the granzyme–perforin pathway depending on IL-2 concentrations.

Keywords

Human CD4+CD25high TregCell deathGranzymesPerforinInterleukin-2

Supplementary material

109_2010_602_MOESM1_ESM.pdf (2.3 mb)
ESM 1(PDF 2341 kb)

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Malgorzata Czystowska
    • 1
  • Laura Strauss
    • 1
  • Christoph Bergmann
    • 1
  • Marta Szajnik
    • 1
  • Hannah Rabinowich
    • 1
  • Theresa L. Whiteside
    • 2
  1. 1.Department of PathologyUniversity of Pittsburgh School of Medicine and University of Pittsburgh Cancer InstitutePittsburghUSA
  2. 2.Departments of Pathology, Immunology and Otolaryngology, Suite L1.27 at the Hillman Cancer CenterUniversity of Pittsburgh Cancer InstitutePittsburghUSA