Seunghee Kim-Schulze

Local and Distant Immunity Induced by Intralesional Vaccination with an Oncolytic Herpes Virus Encoding GM-CSF in Patients with Stage IIIc and IV Melanoma

BackgroundAn oncolytic herpes simplex virus engineered to replicate selectively in tumor cells and to express granulocyte–macrophage colony-stimulating factor (GM-CSF) was tested as a direct intralesional vaccination in melanoma patients. The work reported herein was performed to better characterize the effect of vaccination on local and distant antitumor immunity.MethodsMetastatic melanoma patients with accessible lesions were enrolled in a multicenter 50-patient phase II clinical trial of an oncolytic herpesvirus encoding GM-CSF (OncovexGM-CSF). An initial priming dose of 106 pfu vaccine was given by intratumoral injection, followed by 108 pfu every 2xa0weeks to 24 total doses. Peripheral blood and tumor tissue were collected for analysis of effector T cells, CD4+FoxP3+ regulatory T cells (Treg), CD8+FoxP3+ suppressor T cells (Ts), and myeloid-derived suppressive cells (MDSC).ResultsPhenotypic analysis of T cells derived from tumor samples suggested distinct differences from peripheral blood T cells. There was an increase in melanoma-associated antigen recognized by T cells (MART-1)-specific T cells in tumors undergoing regression after vaccination compared with T cells derived from melanoma patients not treated with vaccine. There was also a significant decrease in Treg and Ts cells in injected lesions compared with noninjected lesions in the same and different melanoma patients. Similarly MDSC were increased in melanoma lesions but underwent a significant decrease only in vaccinated lesions.ConclusionsMelanoma patients present with elevated levels of Tregs, Ts, and MDSC within established tumors. Direct injection of OncovexGM-CSF induces local and systemic antigen-specific T cell responses and decreases Treg, Ts, and MDSC in patients exhibiting therapeutic responses.

Chemoradiotherapy-Induced Upregulation of PD-1 Antagonizes Immunity to HPV-Related Oropharyngeal Cancer

While viral antigens in human papillomavirus (HPV)-related oropharyngeal cancer (HPVOPC) are attractive targets for immunotherapy, the effects of existing standard-of-care therapies on immune responses to HPV are poorly understood. We serially sampled blood from patients with stage III-IV oropharyngeal cancer undergoing concomitant chemoradiotherapy with or without induction chemotherapy. Circulating immunocytes including CD4(+) and CD8(+) T cells, regulatory T cells (Treg), and myeloid-derived suppressor cells (MDSC) were profiled by flow cytometry. Antigen-specific T-cell responses were measured in response to HPV16 E6 and E7 peptide pools. The role of PD-1 signaling in treatment-related immunosuppression was functionally defined by performing HPV-specific T-cell assays in the presence of blocking antibody. While HPV-specific T-cell responses were present in 13 of 18 patients before treatment, 10 of 13 patients lost these responses within 3 months after chemoradiotherapy. Chemoradiotherapy decreased circulating T cells and markedly elevated MDSCs. PD-1 expression on CD4(+) T cells increased by nearly 2.5-fold after chemoradiotherapy, and ex vivo culture with PD-1-blocking antibody enhanced HPV-specific T-cell responses in 8 of 18 samples tested. Chemoradiotherapy suppresses circulating immune responses in patients with HPVOPC by unfavorably altering effector:suppressor immunocyte ratios and upregulating PD-1 expression on CD4(+) T cells. These data strongly support testing of PD-1-blocking agents in combination with standard-of-care chemoradiotherapy for HPVOPC.

Immunoglobulin-like transcript 2 (ILT2) is a biomarker of therapeutic response to oncolytic immunotherapy with vaccinia viruses

BackgroundOncolytic viruses represent a novel form of cancer immunotherapy. Vaccinia viruses encoding human T cell co-stimulatory molecules have demonstrated clinical activity in phase I clinical trials in patients with advanced melanoma. However, predictive biomarkers of therapeutic response have not yet been identified.MethodsA customized microarray was performed to identify changes in peripheral blood mononuclear cell (PBMC) gene expression upon exposure to recombinant oncolytic vaccinia viruses. Up-regulated and down-regulated genes were identified and selected for further analysis using PBMC samples from normal donors and oncolytic virus-treated patients before and after viral injection. Quantitative PCR and flow cytometry of defined T cell subsets was performed to evaluate expression patterns and clinical correlations.ResultsThe microarray identified 301 genes that were up-regulated and 960 genes that were down-regulated in T cells after exposure to oncolytic vaccinia virus. The B7.1 gene was highly up-regulated and the immunoglobulin-like transcript 2 (ILT2) gene was highly down-regulated by vaccinia-B7.1, which was consistent with the known inverse regulation of these two genes. We observed an inverse association between ILT2 expression in the tumor microenvironment and clinical response and further identified ILT2 as a marker of regulatory CD4+ and suppressor CD8+ T cell responses and whose down-regulation was predictive of therapeutic responses in patients treated with oncolytic virus immunotherapy.ConclusionsILT2 is a new putative biomarker of T cell and clinical response in patients treated with oncolytic vaccinia virus immunotherapy. Further confirmation of ILT2 as a biomarker requires prospective validation in a larger series of clinical trials.

Phase 2 Trial of Gemcitabine, Cisplatin, plus Ipilimumab in Patients with Metastatic Urothelial Cancer and Impact of DNA Damage Response Gene Mutations on Outcomes

BACKGROUNDnChemotherapy may exert immunomodulatory effects, thereby combining favorably with the immune checkpoint blockade. The pharmacodynamic effects of such combinations, and potential predictive biomarkers, remain unexplored.nnnOBJECTIVEnTo determine the safety, efficacy, and immunomodulatory effects of gemcitabine and cisplatin (GC) plus ipilimumab and explore the impact of somatic DNA damage response gene alterations on antitumor activity.nnnDESIGN, SETTING, AND PARTICIPANTSnMulticenter single arm phase 2 study enrolling 36 chemotherapy-naïve patients with metastatic urothelial cancer. Peripheral blood flow cytometry was performed serially on all patients and whole exome sequencing of archival tumor tissue was performed on 28/36 patients.nnnINTERVENTIONnTwo cycles of GC followed by four cycles of GC plus ipilimumab.nnnOUTCOME MEASUREMENTS AND STATISTICAL ANALYSISnThe primary endpoint was 1-yr overall survival (OS). Secondary endpoints included safety, objective response rate, and progression-free survival.nnnRESULTS AND LIMITATIONSnGrade ≥3 adverse events occurred in 81% of patients, the majority of which were hematologic. The objective response rate was 69% and 1-yr OS was 61% (lower bound 90% confidence interval: 51%). On exploratory analysis, there were no significant changes in the composition and frequency of circulating immune cells after GC alone. However, there was a significant expansion of circulating CD4 cells with the addition of ipilimumab which correlated with improved survival. The response rate was significantly higher in patients with deleterious somatic DNA damage response mutations (sensitivity=47.6%, specificity=100%, positive predictive value=100%, and negative predictive value=38.9%). Limitations are related to the sample size and single-arm design.nnnCONCLUSIONSnGC+ipilimumab did not achieve the primary endpoint of a lower bound of the 90% confidence interval for 1-yr OS of >60%. However, within the context of a small single-arm trial, the results may inform current approaches combining chemotherapy plus immunotherapy from the standpoint of feasibility, appropriate cytotoxic backbones, and potential predictive biomarkers.nnnTRIAL REGISTRATIONnClinicalTrials.gov NCT01524991.nnnPATIENT SUMMARYnCombining chemotherapy and immune checkpoint blockade in patients with metastatic urothelial cancer is feasible. Further studies are needed to refine optimal combinations and evaluate tests that might identify patients most likely to benefit.

Converting tumors into vaccine manufacturing factories: DC recruitment, activation and clinical responses with a flt3L-primed in situ vaccine for low-grade lymphoma [nct01976585]

Meeting abstractsnnLymphomas are the 5th most common cancer in the U.S. and the most prevalent amongst these, low-grade B cell lymphomas are incurable with standard therapy. Previously, we completed three trials combining low-dose radiotherapy (XRT) with intratumoral administration of a TLR9 agonist

Therapeutic HPV cancer vaccine targeted to CD40 elicits effective CD8+ T-cell immunity

In the U.S., HPV is responsible for more than 26,000 new cancer cases annually. A novel and effective immunotherapeutic vaccine against many types of HPV16-associated cancers was developed that supports targeting vaccines to dendritic cells via CD40. Human papillomavirus (HPV), particularly HPV16 and HPV18, can cause cancers in diverse anatomical sites, including the anogenital and oropharyngeal (throat) regions. Therefore, development of safe and clinically effective therapeutic vaccines is an important goal. Herein, we show that a recombinant fusion protein of a humanized antibody to CD40 fused to HPV16.E6/7 (αCD40-HPV16.E6/7) can evoke HPV16.E6/7-specific CD8+ and CD4+ T-cell responses in head-and-neck cancer patients in vitro and in human CD40 transgenic (hCD40Tg) mice in vivo. The combination of αCD40-HPV16.E6/7 and poly(I:C) efficiently primed HPV16.E6/7-specific T cells, particularly CD8+ T cells, in hCD40Tg mice. Inclusion of montanide enhanced HPV16.E6/7-specific CD4+, but not CD8+, T-cell responses. Poly(I:C) plus αCD40-HPV16.E6/7 was sufficient to mount both preventative and therapeutic immunity against TC-1 tumors in hCD40Tg mice, significantly increasing the frequency of HPV16-specific CD8+ CTLs in the tumors, but not in peripheral blood. In line with this, tumor volume inversely correlated with the frequency of HPV16.E6/7-specific CD8+ T cells in tumors, but not in blood. These data suggest that CD40-targeting vaccines for HPV-associated malignancies can provide a highly immunogenic platform with a strong likelihood of clinical benefit. Data from this study offer strong support for the development of CD40-targeting vaccines for other cancers in the future. Cancer Immunol Res; 4(10); 823–34. ©2016 AACR.

Impact of chemotherapy alone, and chemotherapy plus ipilimumab, on circulating immune cells in patients with metastatic bladder cancer

Meeting abstractsnnMetastatic bladder cancer (MBC) is a relatively chemosensitive neoplasm yet response durations are generally short-lived. Recently, immune checkpoint blockade has demonstrated unparalleled activity in heavily pre-treated patients (pts) with MBC. The role of standard chemotherapy

Gut microbiota density influences host physiology and is shaped by host and microbial factors

To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohn’s disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics.

Abstract LB-095: HPV E7 antigen-expressing Listeria-based immunotherapy (ADXS11-001) prior to robotic surgery for HPV-positive oropharyngeal cancer enhances HPV-specific T cell immunity

Human papilloma virus-associated oropharyngeal cancer (HPVOPC), which accounts for almost 75% of newly diagnosed OPC, is an appealing target for immunotherapy due to the expression of viral antigens. ADXS11-001, a live attenuated Listeria monocytogenes listeriolysin O (LLO) immunotherapeutic agent expressing an HPV16-E7 fusion protein, has been shown to induce HPV-specific T cell responses in animal models, and to have clinical activity in cervical cancer. A phase II “window of opportunity” trial was designed to evaluate the effect of ADXS11-001 on anti-tumor immunity in peripheral blood and the tumor immune microenvironment (TIME) of patients with HPVOPC. Previously untreated, surgically resectable, stage II-IV, HPVOPC patients received two doses of ADXS11-001 over 5 weeks prior to transoral robotic surgery. Formalin-fixed paraffin embedded (FFPE) pre-treatment biopsies and post-treatment surgical resection specimens were banked for studies of the TIME. Peripheral blood samples were collected at multiple time points before, during and after ADXS11-001 administration and after surgery. The TIME was profiled by quantitative multiplex immunofluorescence (qIF) microscopy and conventional HE 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-095.

Anhedonia as a clinical correlate of inflammation in adolescents across psychiatric conditions

Abstract Objectives: Peripheral inflammation has been associated with multiple psychiatric disorders, particularly with depression. However, findings remain inconsistent and unreproducible, most likely due to the disorder’s heterogeneity in phenotypic presentation. Therefore, in the present study, in an effort to account for inter-individual differences in symptom severity, we utilised a dimensional approach to assess the relationships between a broad panel of inflammatory cytokines and key psychiatric symptoms (i.e. depression, anhedonia, anxiety, fatigue and suicidality) in adolescents across psychiatric disorders. We hypothesised that only anhedonia (reflecting deficits of reward function) will be associated with inflammation. Methods: Participants were 54 psychotropic medication-free adolescents with diverse psychiatric conditions and 22 healthy control (HC) adolescents, aged 12–20. We measured 41 cytokines after in vitro lipopolysaccharide stimulation. Mann-Whitney U and Spearman correlation tests examined group comparison and associations, respectively, while accounting for multiple comparisons and confounds, including depression severity adolescent. Results: There were no group differences in cytokine levels. However, as hypothesised, within the psychiatric group, only anhedonia was associated with 19 cytokines, including haematopoietic growth factors, chemokines, pro-inflammatory cytokines, and anti-inflammatory cytokines. Conclusions: Our findings suggest that general inflammation may induce reward dysfunction, which plays a salient role across psychiatric conditions, rather than be specific to one categorical psychiatric disorder.