Intratumoural CD103+CD8+ T cells have been linked to prolonged survival in several malignancies. However, the clinical significance of CD103+CD8+ T cells in gastric cancer remains unexplored.
Gastric cancer tissues from Zhongshan Hospital and data from Gene Expression Omnibus were obtained and analysed. Immunohistochemistry and flow cytometry were performed to detect the number and phenotypical characteristics of CD103+CD8+ T cells. The effect of programmed cell death protein-1 (PD-1) blockade on CD103+CD8+ T cells was evaluated with the use of an in vitro study based on fresh tumour tissues.
CD103+CD8+ T cells predicted superior overall survival and provided better prognostic power than total CD8+ T cells in gastric cancer. Patients with high CD103+CD8+ T cell infiltration also gained more benefit from adjuvant chemotherapy. Flow cytometry analysis showed that CD103+CD8+ T cells exerted superior anti-tumour effects with stronger retention capacity and cytotoxicity. Moreover, an in vitro study showed that CD103+CD8+ T cells were more functionally restored after PD-1 blockade than CD103-CD8+ T cells.
CD103+CD8+ T cells might be a useful marker to predict prognosis and therapeutic efficacy for gastric cancer patients. Efforts to increase intratumoural CD103+CD8+ T cell frequency might be a novel therapeutic strategy in gastric cancer.

Co-stimulation regulates T cell activation, but it remains unclear whether co-stimulatory pathways also control T cell differentiation. We used mass cytometry to profile T cells generated in the genetic absence of the negative co-stimulatory molecules CTLA-4 and PD-1. Our data indicate that negative co-stimulation constrains the possible cell states that peripheral T cells can acquire. CTLA-4 imposes major boundaries on CD4+ T cell phenotypes, whereas PD-1 subtly limits CD8+ T cell phenotypes. By computationally reconstructing T cell differentiation paths, we identified protein expression changes that underlied the abnormal phenotypic expansion and pinpointed when lineage choice events occurred during differentiation. Similar alterations in T cell phenotypes were observed after anti-CTLA-4 and anti-PD-1 antibody blockade. These findings implicate negative co-stimulation as a key regulator and determinant of T cell differentiation and suggest that checkpoint blockade might work in part by altering the limits of T cell phenotypes.
Copyright © 2019 Elsevier Inc. All rights reserved.

The provirus integration site for Moloney murine leukemia virus (Pim) 1 kinase is an oncogenic serine/threonine kinase implicated in cytokine-induced cell signaling, whereas Runt-related transcription factor (Runx) has been implicated in the regulation of T-cell differentiation. The interaction of Pim1 kinase and Runx3 in the pathogenesis of peanut allergy has not been defined.
We sought to determine the effects of Pim1 kinase modulation on Runx3 expression and T(H)2 and T(H)17 cell function in an experimental model of peanut allergy.
A Pim1 kinase inhibitor was administered to peanut-sensitized and challenged wild-type and Runx3(+/-) mice. Symptoms, intestinal inflammation, and Pim1 kinase and Runx3 mRNA expression and protein levels were assessed. The effects of Pim1 kinase inhibition on T(H)1, T(H)2, and T(H)17 differentiation in vivo and in vitro were also determined.
Peanut sensitization and challenge resulted in accumulation of inflammatory cells and goblet cell metaplasia and increased levels of Pim1 kinase and T(H)2 and T(H)17 cytokine production but decreased levels of Runx3 mRNA and protein in the small intestines of wild-type mice. All of these findings were normalized with Pim1 kinase inhibition. In sensitized and challenged Runx3(+/-) mice, inhibition of Pim1 kinase had less effect on the development of the full spectrum of intestinal allergic responses. In vitro inhibition of Pim1 kinase attenuated T(H)2 and T(H)17 cell differentiation and expansion while maintaining Runx3 expression in T-cell cultures from wild-type mice; these effects were reduced in T-cell cultures from Runx3(+/-) mice.
These data support a novel regulatory axis involving Pim1 kinase and Runx3 in the control of food-induced allergic reactions through the regulation of T(H)2 and T(H)17 differentiation.
Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.