Checks and Balances

2018 ◽  
pp. 153-156
Author(s):  
Aaron E. Miller ◽  
Tracy M. DeAngelis ◽  
Michelle Fabian ◽  
Ilana Katz Sand
Keyword(s):  
T Cells ◽  
T Cell Activation ◽  
Immune Checkpoint ◽  
Cell Activation ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
Healthy Person ◽  
Checks And Balances ◽  
Autoimmune Conditions ◽  
Checkpoint Inhibitor Therapy

In recent years, immune checkpoint inhibitors have been shown to be effective tools in treating multiple types of cancer. In a healthy person, immune checkpoint molecules function to remove self-reactive T cells. However, cancer cells may also use these same pathways to suppress T cells. Checkpoint inhibition brings about non-specific T cell activation, which allows for a tumor-specific immune response. However, an infrequent, but potentially severe, complication of checkpoint inhibitor therapies is the formation of autoimmune conditions. Cases of new or worsened autoimmune conditions have been reported in many organ systems. In the nervous system, central and peripheral processes, as well as disorders of the neuro-muscular junction or muscle, have been identified. Treatment is targeted towards the acute episode. Chronic immunosuppression is usually not initiated because stopping the checkpoint inhibitor therapy will typically abort the autoimmune process. In the future, more of these drugs are likely to be used to treat cancer, and thus more must be known about the mechanisms that induce autoimmunity in this setting and the best strategies to treat them.

scholarly journals A review on immune checkpoint blockage therapy

2020 ◽  
Vol 2 (1) ◽  
pp. 12-17
Author(s):  
Thamrook s Shajahan ◽  
Shaiju S Dharan ◽  
Merlin Nj
Keyword(s):  
T Cells ◽  
Immune System ◽  
T Cell ◽  
Cancer Cells ◽  
T Cell Activation ◽  
Immune Checkpoint ◽  
Immune Cell ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
The Body

Activating the immune system to eliminate cancer cells and produce clinically relevant response has been a long standing goal of cancer research. Most promising therapeutic approaches of activating antitumor immunity include immune checkpoint inhibitors. Our immune system protect us from disease, killing bacteria and virus. One main type of immune cell called T-cells. T-cells have protein that turn it off. These are called checkpoint. Immune checkpoint are accessory molecules that either promote or inhibit T-cell activation. Checkpoint inhibitor are a type of immunotherapy. They block protein that stops the immune system from attacking the cancer cells. Checkpoint inhibitor are a type of monoclonal antibody or targeted treatment. Immune system cells, such as T-cells and Antigen presenting cells (APCs), defend and protect the body. Immune system play an important role in controlling and eradicating cancer. Cytotoxic T lymphocytes associated protein 4(CTLA-4) and Programmed cell dealth protein (PD-1) are checkpoint protein which is the negative regulation of T-cell immune function. Inhibition of the target, results in increased activation of immune system.

scholarly journals 643 Vasoactive intestinal peptide as a novel immune checkpoint molecule in activated T cells

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A672-A672
Author(s):  
Sruthi Ravindranathan ◽  
Tenzin Passang Fnu ◽  
Edmund Waller
Keyword(s):  
T Cells ◽  
T Cell ◽  
Vasoactive Intestinal Peptide ◽  
T Cell Activation ◽  
Cd8 T Cells ◽  
Immune Checkpoint ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Checkpoint Inhibitors ◽  
Activated T Cells

BackgroundOnly a fraction of cancer patients responds to current antibody-based immune checkpoint inhibitors.1 Our lab has identified vasoactive intestinal peptide-receptor (VIP-R) signaling as a targetable immune checkpoint pathway in cancer. VIP is a small neuropeptide with known immunosuppressive effects on T cells, in particular, CD4+ T cells.2–5 However, little is known about VIP-R signaling in CD8+ T cells. To define mechanisms by which VIP limits T cell activation and function, we studied the regulation of VIP and VIP receptors (VIP-R) in T cells following their activation in vitro and in mouse models of cancer.MethodsT cells from healthy human donors and murine splenocytes were activated using anti-CD3 coated plates. Western blots measured intracellular pre-pro-VIP, along with its cognate receptors; VPAC1 and VPAC2. Purified cultures of CD4+ and CD8+ T cells were used to interrogate the protein expression on specific T cell subsets. Activation and chemokine receptor expression was assessed by flow cytometry to evaluate T cell response to VIP-R antagonists in vitro and in tumor-bearing mice engrafted with pancreatic cancer cell lines.ResultsBoth murine and human T cells upregulate pre-pro-VIP following TCR stimulation with similar kinetics of VIP receptors between species. VIP expression is upregulated in vivo following treatment of tumor-bearing mice with anti-PD1 MoAb. VIP expression is temporally correlated with the upregulation of other co-inhibitory molecules. VPAC1 expression modestly increased in activated T cells while VPAC2 expression decreased. A non-canonical high molecular weight (HMW) form of VPAC2-related protein robustly and transiently increase in activated T cells. Expression of HMW form of VPAC2 is only detected in activated CD4+ T cells. Of note, activated CD4+ but not CD8+ T cells upregulate pre-pro-VIP. Pharmacological inhibition of VIP-R signaling significantly increased CD69+, OX40+, Lag3+, and PD1+ expression in CD4+ subsets compared to activated T cells without VIP-R antagonists (p < 0.05). In contrast, CD8+ T cells upregulate VPAC1 but not VPAC2 receptor following activation. VIP-R antagonist treatment of activated CD8+ T cells significantly decreased CXCR4+ expression (p < 0.05). CXCR3 and CXCR5 expression were not affected by VIP-R antagonist treatment.ConclusionsVIP-R signaling is a novel immune autocrine and paracrine checkpoint pathway in activated CD4+ T cells. Activated CD4+ and CD8+ T cells demonstrate different kinetics of VPAC1 and VPAC2 expression, suggesting different immune-regulatory responses to VIP-R antagonists. Understanding VIP-R signaling induced during T cell activation can lead to specific drugs that target VIP-R pathways to enhance cancer immunotherapy.AcknowledgementsWe thank healthy volunteers for blood samples. The authors also thank the shared resources at Emory University, namely, Emory Flow Cytometry Core (EFCC) and Integrated Cellular Imaging Core (ICI) and Yerkes Nonhuman Primate Genomics Core that provided services or instruments at subsidized cost to conduct some of the reported experiments. This work was supported in part by Katz Foundation funding, Georgia Research Alliance, and Emory School of Medicine Dean's Imagine, Innovate and Impact (I3) venture award to Edmund K. Waller.ReferencesDarvin P, Toor SM, Sasidharan Nair V, Elkord E. Immune checkpoint inhibitors: recent progress and potential biomarkers. Experimental and Molecular Medicine 2018.Wang HY, Jiang XM, Ganea D. The Neuropeptides VIP and PACAP Inhibit IL-2 Transcription by Decreasing c-Jun and Increasing JunB Expression in T Cells. J Neuroimmunol 2000;104(1):68–78.Delgado M. Vasoactive intestinal peptide generates CD4+CD25+ regulatory T Cells in Vivo. J Leukoc Biol 2005.Anderson P, Gonzalez-Rey E. Vasoactive intestinal peptide induces cell cycle arrest and regulatory functions in human T cells at multiple levels. Mol Cell Biol 2010.Delgado M, Ganea D. Vasoactive intestinal peptide: a neuropeptide with pleiotropic immune functions. Amino Acids. NIH Public Access July 2013, 25–39.Ethics ApprovalDe-identified blood samples from consented healthy volunteers (IRB 00046063) were obtained with approval from Institutional Review Boards.

scholarly journals 781 Validation of the combinatorial effect of blinatumomab and nivolumab in cancer therapy

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A831-A831
Author(s):  
Tienan Wang ◽  
Qing Lin ◽  
Jie Zhang
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cd8 T Cells ◽  
Immune Checkpoint ◽  
Culture System ◽  
Cell Activation ◽  
Checkpoint Inhibitors

BackgroundCancer immunotherapies, including immune checkpoint inhibitors, CAR-T, cancer vaccines and bispecific antibodies, have been brought to spot light in recent years as several therapeutic strategies targeting the immune system have produced exciting clinical results. Bispecific antibody typically play dual roles in blocking the immune checkpoint and redirecting/re-boosting the function of the immune effector cells. Blinatumomab belongs to CD3 bispecific T cell engager (CD3 BiTE), which was engineered to harbor two arms binding with CD3 and CD19 simultaneously and direct CD8+ T cells to specifically recognize CD19 positive lymphoma cells to execute cytotoxicity. Approval of Blinatumomab for patients with relapse/refractory B cell acute lymphoblastic leukemia (ALL) has driven remarkable increase in combination studies of Blinatumomab with other immunotherapies such as checkpoint inhibitors.MethodsIn this study, we developed CD8+ T cytotoxic system targeting different B lymphoma cell line and fully validated the function of Blinatumomab in promoting target tumor cell lysis by primary CD8+ T cells (figure 1). In addition, we established a mixed lymphocyte and tumor system to mimic physiological TME to dissect the combinational role of Nivolumab and Blinatumomab (figure 2).ResultsThe result suggest that combinatory therapy is highly depend on the dosage of Blinatumomab and also T cell number in the TME, which might give an instruction for ongoing clinical trial design. Finally, we have employed humanized mouse models bearing Raji or Daudi tumor cells to further validate this combination treatment in vivo. Both In-vivo and In-vitro data support that Blinatumomab is dominant in activing T cell and Nivolumab can only exhibit synergistic effect under suboptimal dosage of Blinatumomab.Abstract 781 Figure 1Establishment of In vitro co-culture system for CD3 BiTEestablish in vitro human PBMC based system to validate CD3 BiTE functionAbstract 781 Figure 2Opdivo and CD3 BiTE CombinationOpdivo could further promote T cell activation under the treatment of CD3 BiTEConclusionsSuccessfully establish in vitro system to evaluate the function of CD3 BiTE and also take advantage of MLR/tumor co-culture system to demonstrate PD1 antibody could further promote T cell activation under appropriate dosage of CD3 BiTE.

scholarly journals CNS demyelination associated with immune dysregulation and a novel CTLA-4 variant

2021 ◽  
pp. 135245852096389
Author(s):  
Stefania Kaninia ◽  
Alexandros Grammatikos ◽  
Kathryn Urankar ◽  
Shelley A Renowden ◽  
Nikunj K Patel ◽  
...  
Keyword(s):  
T Cell Activation ◽  
Cell Activation ◽  
Cytotoxic T Lymphocyte ◽  
Checkpoint Inhibitors ◽  
Novel Treatments ◽  
First Case ◽  
Self Tolerance ◽  
Autoimmune Conditions ◽  
History Of ◽  
Cns Demyelination

Background: The cytotoxic T-lymphocyte antigen-4 (CTLA-4) pathway acts as a negative immune regulator of T-cell activation and promotes self-tolerance. Case: We report the first case of biopsy-proven central nervous system inflammatory demyelination in the context of primary immunodeficiency and a novel CTLA-4 variant. Conclusion: This case has significant implications for the development of novel treatments for autoimmune conditions including multiple sclerosis and further emphasises the need for caution with clinical use of CTLA-4 immune checkpoint inhibitors in those with a history of inflammatory demyelination.

scholarly journals Enterococcus peptidoglycan remodeling promotes immune checkpoint inhibitor therapy

2020 ◽  
Author(s):  
Matthew E. Griffin ◽  
Juliel Espinosa ◽  
Jessica L. Becker ◽  
Jyoti K. Jha ◽  
Gary R. Fanger ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Immune Checkpoint ◽  
Molecular Mechanisms ◽  
Immune Checkpoint Inhibitor ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
Mouse Tumor ◽  
Peptidoglycan Hydrolases ◽  
Checkpoint Inhibitor Therapy ◽  
Specific Species

AbstractThe antitumor efficacy of cancer immunotherapy has been correlated with specific species within the gut microbiota. However, molecular mechanisms by which these microbes affect host response to immunotherapy remain elusive. Here we show that specific members of the bacterial genus Enterococcus can promote anti-PD-L1 immunotherapy in mouse tumor models. The active enterococci express and secrete orthologs of the NlpC/p60 peptidoglycan hydrolase SagA that generate immune-active muropeptides. Expression of SagA in non-protective E. faecalis was sufficient to promote antitumor activity of clinically approved checkpoint targets, and its activity required the peptidoglycan sensor Nod2. Notably, SagA-engineered probiotics or synthetic muropeptides also promoted checkpoint inhibitor antitumor activity. Our data suggest that microbiota species with unique peptidoglycan remodeling activity may enhance immunotherapy and could be leveraged for next-generation adjuvants.One Sentence SummaryA conserved family of secreted NlpC/p60 peptidoglycan hydrolases from Enterococcus promote antitumor activity of immune checkpoint inhibitors.

EP.WE.805From bench to bedside; A rationale for Immunotherapy in the adjuvant setting for Oesophageal cancer

2021 ◽  
Vol 108 (Supplement_7) ◽  
Author(s):  
Noel Donlon ◽  
Maria Davern ◽  
Andrew Sheppard ◽  
John Reynolds ◽  
Joanne Lysaght
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Immune Checkpoint ◽  
Cell Activation ◽  
Single Agent ◽  
T Cell Subsets ◽  
Effector Memory ◽  
Post Surgery ◽  
Post Operative Period

Abstract Background Immunotherapy is being intensively investigated for its utilisation in the curative setting as a single agent and in the multimodal setting, however, the most appropriate time to incorporate ICIs remains unknown. Our study profiles systemic anti-tumour immunity perioperatively to provide a rationale for adjuvant immunotherapy. Methods Systemic immunity was immunophenotyped pre and post-oesophagectomy on days 0, 1, 3, 7 and week 6 by flow cytometry (n = 14). The frequency of circulating lymphocytes, T cells, cytotoxic and helper T lymphocytes was profiled longitudinally including the proportion of T cell subsets in circulation. This study also profiled immune checkpoint expression on circulating T cells including: PD-1, CTLA-4, TIGIT, TIM-3, LAG-3, PD-L1 and PD-L2. Markers of immunogenicity (calreticulin, HMGB1 and MIC-A/B) were also assessed. Results The frequency of circulating CD27 + T cells increases sequentially in the immediate post-operative period peaking on day 7 in OAC patients. (p &lt; 0.01) There is a sequential decrease in the percentage of effector memory and central memory T cells in circulation and an increase in the percentage of naïve T cells in peripheral circulation of OAC patients in the immediate post-operative period. The expression of CTLA-4 on the surface of circulating CD4 + T cells decreases 6 weeks post-operatively in OAC patients. Conclusions We observed increased T cell activation and immune checkpoints immediately post-surgery with returns to baseline by week 6. These results suggest that immune checkpoint inhibitors such as anti-PD-1 may be beneficial immediately post-surgery to maintain T cell activation and prevent exhaustion of this increased population of activated T cells observed immediately post-surgery.

Peritoneal melanosis associated with metastatic melanoma previously treated with targeted and immune checkpoint inhibitor therapy

2021 ◽  
Vol 14 (1) ◽  
pp. e238235
Author(s):  
Kwang Kiat Sim ◽  
Katie Connell ◽  
Mayank Bhandari ◽  
David Paton
Keyword(s):  
Metastatic Melanoma ◽  
Immune Checkpoint ◽  
Immune Checkpoint Inhibitor ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
Inhibitor Therapy ◽  
Tumour Regression ◽  
Benign Condition ◽  
Checkpoint Inhibitor Therapy ◽  
Previously Treated

Peritoneal melanosis is an uncommon benign condition, the pathophysiology of which is unclear. Macroscopically, it appears as diffuse dark brown or black pigmentation within the peritoneum, mimicking more sinister conditions such as metastatic melanoma. It has been described in a variety of contexts, but only exceedingly rarely in association with metastatic melanoma, with only two previous published case reports. We present a case of peritoneal melanosis associated with metastatic melanoma involving the spleen, previously treated with targeted and immune checkpoint inhibitor therapy. With increasing reports of melanoma regression manifesting as cutaneous tumorous melanosis in patients treated with immune checkpoint inhibitors, we postulate that, similarly, immunotherapy and tumour regression might have a role to play in the pathogenesis of the peritoneal pigmentation in this case.

scholarly journals Immune Checkpoint Inhibitor Therapy in Patients With Preexisting Inflammatory Bowel Disease

2020 ◽  
Vol 38 (6) ◽  
pp. 576-583 ◽  
Author(s):  
Hamzah Abu-Sbeih ◽  
David M. Faleck ◽  
Biagio Ricciuti ◽  
Robin B. Mendelsohn ◽  
Abdul R. Naqash ◽  
...  
Keyword(s):  
Adverse Events ◽  
T Lymphocyte ◽  
Immune Checkpoint ◽  
Immune Checkpoint Inhibitor ◽  
Cytotoxic T Lymphocyte ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
Inhibitor Therapy ◽  
Checkpoint Inhibitor Therapy ◽  
Inflammatory Bowel

PURPOSE The risk of immune checkpoint inhibitor therapy–related GI adverse events in patients with cancer and inflammatory bowel disease (IBD) has not been well described. We characterized GI adverse events in patients with underlying IBD who received immune checkpoint inhibitors. PATIENTS AND METHODS We performed a multicenter, retrospective study of patients with documented IBD who received immune checkpoint inhibitor therapy between January 2010 and February 2019. Backward selection and multivariate logistic regression were conducted to assess risk of GI adverse events. RESULTS Of the 102 included patients, 17 received therapy targeting cytotoxic T-lymphocyte antigen-4, and 85 received monotherapy targeting programmed cell death 1 or its ligand. Half of the patients had Crohn’s disease, and half had ulcerative colitis. The median time from last active IBD episode to immunotherapy initiation was 5 years (interquartile range, 3-12 years). Forty-three patients were not receiving treatment of IBD. GI adverse events occurred in 42 patients (41%) after a median of 62 days (interquartile range, 33-123 days), a rate higher than that among similar patients without underlying IBD who were treated at centers participating in the study (11%; P < .001). GI events among patients with IBD included grade 3 or 4 diarrhea in 21 patients (21%). Four patients experienced colonic perforation, 2 of whom required surgery. No GI adverse event–related deaths were recorded. Anti–cytotoxic T-lymphocyte antigen-4 therapy was associated with increased risk of GI adverse events on univariable but not multivariable analysis (odds ratio, 3.19; 95% CI, 1.8 to 9.48; P = .037; and odds ratio, 4.72; 95% CI, 0.95 to 23.53; P = .058, respectively). CONCLUSION Preexisting IBD increases the risk of severe GI adverse events in patients treated with immune checkpoint inhibitors.

scholarly journals Releasing the brakes: a case report of pulmonary arterial hypertension induced by immune checkpoint inhibitor therapy

2020 ◽  
Vol 10 (4) ◽  
pp. 204589402096096 ◽  
Author(s):  
Matthew Glick ◽  
Chase Baxter ◽  
David Lopez ◽  
Kashif Mufti ◽  
Stephen Sawada ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Lupus Erythematosus ◽  
Immune Checkpoint ◽  
Immune Checkpoint Inhibitors ◽  
Immune Checkpoint Inhibitor ◽  
Checkpoint Inhibitor ◽  
Checkpoint Inhibitors ◽  
Checkpoint Inhibitor Therapy ◽  
Pulmonary Arterial

Immune checkpoint inhibitors successfully treat various malignancies by inducing an immune response to tumor cells. However, their use has been associated with a variety of autoimmune disorders, such as diabetes, hepatitis, and pneumonitis. Pulmonary arterial hypertension due to checkpoint inhibitor use has not yet been described. We present a novel case of pulmonary arterial hypertension associated with systemic lupus erythematosus and Sjogren’s syndrome overlap that was induced by therapy with the checkpoint inhibitor durvalumab.

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