Abstract 5400
Background
Type 1 regulatory (Tr1) T cells, like every effector T cells, arise from stimulation of naïve T cell precursor and enter a long term memory pool. While they can adapt their function to specific environmental cues, sometimes called plasticity, their phenotype remains broadly fixed. Unlike natural T regulator cells that emerge from the thymus with a defined phenotype (CD4+CD25hiCD127loFoxP3+), there is uncertainty over the characterisation of inducible Tr1 cells.
Methods
In this study we stimulated human total CD4+ T cells with PMA/ Ionomycin and also demonstrated that these cells respond specifically to costimulation via CD97-CD55. Dual cell surface capture (CSA) was used to assay for IL-10 and IFN-γ and intracellular staining for Tr1 markers.
Results
A small (<5%) population were IL-10+ IL-4-, IFN-γ- and expressed other markers commonly associated with Tr1-like cells. These included; CD49b, LAG-3, CD226, PD-1, CTLA-4, and TIM-3. However they were negative for FoxP3 expression, and expressed Cmaf, which is thought to be responsible for the transcriptional events within this population. Furthermore, we show that these Tr1-like cells form part of the immunological memory and reside predominantly within the effector memory (CD62L- CD45RO+, TEM) pool. Unlike the majority of other studies where Tr1 is generated by chronic stimulation of PBMCs in the presence of recombinant IL-10 for several days, as far as we are aware, this is the first report characterising Tr1 directly ex vivo from human peripheral blood.
Conclusions
We have also demonstrated that these cells respond specifically to costimulation via CD97-CD55 to drive proliferation and maintain the IL-10 single positive, Tr1 phenotype outlined above. This supports the idea that once differentiated from naïve precursors, Tr1-like cells respond to CD55 costimulation to maintain a small (<5%) pool with a committed IL-10+ IL-4-IFN-γ- phenotype.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The University of Nottingham.
Funding
The Commonwealth Scholarships Commission, London.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5437 - Salivary cytokines and oral mucosa cells apoptosis in patients during hematopoietic cell transplantation: possible relationship with oral mucositis
Presenter: Luciana Corrêa
Session: Poster Display session 1
Resources:
Abstract
1483 - A randomized trial of sodium alginate prevention of radiation-induced esophagitis in patients with locally advanced NSCLC receiving concurrent chemoradiotherapy: OLCSG1401
Presenter: Toshihide Yokoyama
Session: Poster Display session 1
Resources:
Abstract
2047 - Taste and smell alterations (TSAs) in patients (pts) with stage II-III colon cancer (CC): a pilot within the PROTECT study
Presenter: Jeroen Derksen
Session: Poster Display session 1
Resources:
Abstract
5984 - Clinical characteristics are associated with acupuncture treatment response for xerostomia in cancer patients
Presenter: Wenli Liu
Session: Poster Display session 1
Resources:
Abstract
2845 - Psychosocial Distress of Adolescent and Young Adults with Cancer at Diagnosis: A Case-Matched Retrospective Cohort of 2045 Patients in British Columbia.
Presenter: Alannah Smrke
Session: Poster Display session 1
Resources:
Abstract
724 - Accuracy of distress thermometer to measure cancer-related mood disorders in Chinese patients with cancer
Presenter: Sudip Thapa
Session: Poster Display session 1
Resources:
Abstract
2357 - Modalities of biosimilar filgrastim use in clinical practice in >1000 patients receiving chemotherapy regimens with a rest period of ≤14 days: the TOPAZE study
Presenter: Jean Marc Phelip
Session: Poster Display session 1
Resources:
Abstract
1426 - The Effect of Increasing Doses of Pegfilgrastim (Peg) on Thrombocytopenia (T) in Breast Cancer (BC) Patients (pts) Receiving Taxotere (Doc), Doxorubicin, Cyclophosphamide (TAC) and Plinabulin (Plin)
Presenter: Douglas Blayney
Session: Poster Display session 1
Resources:
Abstract
712 - The use of intravenous ferric carboxymaltose without erythropoiesis-stimulating agents in the treatment of anemia in cancer patients undergoing chemotherapy with or without radiotherapy
Presenter: Hikmat Abdel-Razeq
Session: Poster Display session 1
Resources:
Abstract
1496 - Randomized, double-blind, cross-over Phase I study comparing pharmacokinetics, pharmacodynamics, safety and immunogenicity of a biosimilar pegfilgrastim with EU and US references
Presenter: Maria Velinova
Session: Poster Display session 1
Resources:
Abstract