Abstract 5650
Background
Up to 44% of patients receiving combination ipilimumab and nivolumab develop checkpoint-inhibitor-(CI) colitis, however its molecular pathogenesis is poorly understood. We aimed to characterise peripheral blood and gut mononuclear cells (PBMC; GMNC) in patients with CI-colitis and controls to gain insights into disease aetiology. We were particularly interested in activated, memory, gut-homing CD8+ T-cells and also the innate-like mucosal-associated invariant T (MAIT) cells that play important roles in mucosal immunity.
Methods
In Cohort I PBMC from patients with CI-colitis (N = 9) were compared with those from patients who received CI with no adverse-events (CI-controls; N = 11), patients with active ulcerative colitis (UC; N = 6) and Healthy Volunteers (N = 16). PBMC findings were tested in a second cohort (Cohort II; IN-Colitis N = 15; IN-NAE=9). GMNC were isolated in Cohort III (IN-colitis N = 5; IN-controls N = 5; UC N = 6; Healthy Volunteers N = 6). Flow-cytometric analysis was used throughout.
Results
CI-colitis patients had low circulating MAIT cells compared with CI-controls at baseline in Cohort I. Low levels of circulating MAIT cells in both CI-colitis and CI-controls (compared to Healthy Volunteers) were found in Cohort II. CI-treated patients had high levels of activated-memory T-cells in peripheral blood (CD8 + >CD4+) that included a gut-homing population, regardless of the development of colitis. However, activation of circulating MAIT cells was not evident. In gut tissue there was elevation of activated, granzyme-B+ MAIT cells in CI-colitis compared with CI-controls. CI-colitis was characterised by an activated-memory CD8+ lymphocytosis.
Conclusions
Melanoma patients can have low baseline circulating MAIT cells. In one cohort this associated with CI-colitis. In tissue, activated MAIT cells were elevated in CI-colitis. Further work is needed to determine which immune populations are useful for the prediction and prognostication of CI-colitis, and if MAIT cells contribute to tissue damage or repair.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Celgene.
Disclosure
S.C. Sasson: Research grant / Funding (institution): Celgene. V.T.F. Cheung: Speaker Bureau / Expert testimony: Janssen. G.V. Long: Advisory / Consultancy: Aduro; Advisory / Consultancy: Amgen; Advisory / Consultancy: BMS; Advisory / Consultancy: Merck MSD; Advisory / Consultancy: Mass-Array; Advisory / Consultancy: Novartis; Advisory / Consultancy: Pierre Fabre; Advisory / Consultancy: Roche. M.R. Middleton: Advisory / Consultancy: Amgen; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: BMS; Advisory / Consultancy: Eisai; Advisory / Consultancy: Lilli; Advisory / Consultancy: Merck; Advisory / Consultancy: Millenium; Advisory / Consultancy: Novartis; Advisory / Consultancy: Physiomics; Advisory / Consultancy: Rignotec; Advisory / Consultancy: Roche. O. Brain: Speaker Bureau / Expert testimony: BMS; Research grant / Funding (institution): Celgene. All other authors have declared no conflicts of interest.
Resources from the same session
3628 - Predictive model for survival in advanced non-small-cell lung cancer (NSCLC) treated with frontline pembrolizumab
Presenter: Xabier Mielgo Rubio
Session: Poster Display session 3
Resources:
Abstract
5705 - External validation and longitudinal extension of the LIPI (Lung Immune Prognostic Index) for immunotherapy outcomes in advanced non-small cell lung cancer.
Presenter: Jakob Riedl
Session: Poster Display session 3
Resources:
Abstract
5758 - Changes of TCR Repertoire in Metastatic Renal Cell Carcinoma and Metastatic Melanoma Patients Treated with Nivolumab
Presenter: Martin Klabusay
Session: Poster Display session 3
Resources:
Abstract
1743 - Expression of MHC class I, HLA-A and HLA-B identifies immune activated breast tumors with favorable outcome
Presenter: María Del Mar Noblejas López
Session: Poster Display session 3
Resources:
Abstract
2219 - Prognostic Significance of Tumor Tissue NeuGcGM3 Ganglioside Expression and Predictive Value of Circulating Tumor Cell Count Monitoring in Patients Receiving Racotumomab Immunotherapy
Presenter: Necdet Üskent
Session: Poster Display session 3
Resources:
Abstract
2996 - Evolution of Myeloid-Derived Suppressor Cells and Objective Response Rate in Relapsed/Refractory Diffuse Large B Cell Lymphoma (R/R DLBCL) patients after receiving immunotherapy
Presenter: Carlos Jiménez Cortegana
Session: Poster Display session 3
Resources:
Abstract
2110 - A Phase Ia/Ib trial of the anti-programmed death-ligand 1 (PD-L1) human monoclonal antibody (mAb), CS1001, in patients (pts) with advanced solid tumors or lymphomas
Presenter: Lin Shen
Session: Poster Display session 3
Resources:
Abstract
3515 - Results from a randomised Phase 1/2 trial evaluating the safety and antitumour activity of anti-PD-1 (MEDI0680)/anti-PD-L1 (durvalumab) vs anti-PD-1 (nivolumab) alone in metastatic clear cell renal cell carcinoma (ccRCC)
Presenter: Martin Voss
Session: Poster Display session 3
Resources:
Abstract
3566 - Pembrolizumab in Advanced Rare Cancers
Presenter: Aung Naing
Session: Poster Display session 3
Resources:
Abstract
3567 - High clinical benefit rates of pembrolizumab in very rare sarcoma histotypes: first results of the AcSé Pembrolizumab study
Presenter: Jean-Yves Blay
Session: Poster Display session 3
Resources:
Abstract