Abstract 3823: Viral transcript and tumor immune microenvironment-based transcriptomic profiling of HPV-associated head and neck cancer identifies subtypes associated with prognosis

Human papillomavirus (HPV)-associated Head and Neck Squamous Cell Carcinoma (HPV+HNSCC) is now the most common HPV-associated malignancy in the United States. Current treatments can be associated with severe side-effects or lack of efficacy yet prognostic biomarkers are limited, slowing efforts to personalize treatment in HPV+HNSCC. Here, we describe the use of a transcriptomic-based analytical platform to analyze expression patterns of viral transcripts, the tumor microenvironment (TME), and viral genome integration, and associate these features with overall survival.

Functional gene expression signatures were analyzed on publicly available HPV+HNSCC expression data (n=266). Unsupervised clustering analysis revealed 5 distinct and novel TME types across patients (immune-enriched non-fibrotic, immune-enriched fibrotic, fibrotic, immune-desert, immune-enriched luminal). These microenvironment subtypes were highly correlated with both overall survival and patient prognosis. Tumors with an immune-enriched microenvironment showed the highest survival rates, whereas fibrotic TME types were associated with poor survival (p < 0.05). Unsupervised clustering of a HPV+HNSCC cohort from The Cancer Genome Atlas (TCGA) (n=53), based on HPV transcript expression, revealed 4 HPV-related subtypes. Each subtype was enriched for distinct viral transcripts: E2/E5, E6/E7, E1/E4 and L1/L2. We then validated TME and HPV transcript-related classifications on an independent HPV+HNSCC cohort (n=132). Utilizing both viral transcript and TME subtypes, we found that the E2/E5 HPV subtype was associated with an immune-enriched TME and had a higher overall survival compared to the other subtypes. The E2/E5 subtype was also enriched for samples without HPV-genome integration, suggesting that HPV episomal DNA status and E2/E5 expression pattern may drive an inflamed microenvironment and improved prognosis. In contrast, E6/E7 subtype samples were associated with the fibrotic and depleted TME types, with lower values of T-cell and B-cell gene expression signatures and a lower survival rate. Both E1/E4 and L1/L2 subtypes were associated with the immune-enriched luminal TME types.

These findings suggest that HPV-transcript expression patterns may drive modulation of the TME, and hence impact prognosis. Further validation of the relationships between viral gene expression, TME, and prognosis is warranted to understand if such subtypes could aid in the development of prognostic biomarkers for treatment selection.

Citation Format: Daria Kiriy, Dmitry Tychinin, Nikita Kotlov, Olga Kudryashova, Anastasia Nikitina, Andrey Tyshevich, Naira Samarina, Ksenia Demina, Sandrine Degryse, Susan Raju Paul, Mark Poznansky, Krystle Lang Kuhs, James S. Lewis, Robert L. Ferris, Xiaowei Wang, Alexander Bagaev, Nathan Fowler, Lori Wirth, Daniel Faden. Viral transcript and tumor immune microenvironment-based transcriptomic profiling of HPV-associated head and neck cancer identifies subtypes associated with prognosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3823.

Response to Severe Acute Respiratory Syndrome Coronavirus 2 Initial Series and Additional Dose Vaccine in Patients With Predominant Antibody Deficiency

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with predominant antibody deficiency (PAD) is associated with high morbidity, yet data regarding the response to SARS-CoV-2 immunization in PAD patients, including additional dose vaccine, are limited.

OBJECTIVE

To characterize antibody response to SARS-CoV-2 vaccine in PAD patients and define correlates of vaccine response.

METHODS

We assessed the levels and function of anti-SARS-CoV-2 antibodies in 62 PAD patients compared with matched healthy controls at baseline, at 4 to 6 weeks after the initial series of immunization (a single dose of Ad26.COV2.S [Janssen] or two doses of BNT162b2 [Pfizer-BioNTech] or mRNA-1273 [Moderna]), and at 4 to 6 weeks after an additional dose immunization, if received.

RESULTS

After the initial series of SARS-CoV-2 vaccination, PAD patients had lower mean anti-spike antibody levels compared with matched healthy controls (140.1 vs 547.3 U/mL; P = .02). Patients with secondary PAD (eg, B-cell depletion therapy was used) and those with severe primary PAD (eg, common variable immunodeficiency with autoinflammatory complications) had the lowest mean anti-spike antibody levels. Immune correlates of a low anti-spike antibody response included low CD4+ T helper cells, low CD19+ total B cells, and low class-switched memory (CD27+IgD/M-) B cells. In addition, a low (<100 U/mL) anti-spike antibody response was associated with prior exposure to B-cell depletion therapy, both at any time in the past (odds ratio = 5.5; confidence interval, 1.5-20.4; P = .01) and proximal to vaccination (odds ratio = 36.4; confidence interval, 1.7-791.9; P = .02). Additional dose immunization with an mRNA vaccine in a subset of 31 PAD patients increased mean anti-spike antibody levels (76.3 U/mL before to 1065 U/mL after the additional dose; P < .0001).

CONCLUSIONS

Patients with secondary and severe primary PAD, characterized by low T helper cells, low B cells, and/or low class-switched memory B cells, were at risk for low antibody response to SARS-CoV-2 immunization, which improved after an additional dose vaccination in most patients.

Deep immune profiling of whole blood to identify early immune signatures that correlate to patient outcome after major trauma

BACKGROUND

Major injury results in an early cascade of immunologic responses that increase susceptibility to infection and multiorgan dysfunction. Detailed immune profiling by mass cytometry has the potential to identify immune signatures that correspond to patient outcomes. Our objective was to determine the prognostic value of immune signatures early after major trauma injury.

METHODS

Trauma patients (n = 17) were prospectively enrolled between September 2018 and December 2019. Serial whole blood samples were obtained from trauma patients (mean Injury Severity Score, 26.2; standard error of the mean, 3.7) at Days 1 and 3 after injury, and from age- and sex-matched uninjured controls using a standardized protocol for fixation, storage, and labeling. Computational analyses including K-nearest neighbor automated clustering of immune cells and Spearman's correlation analysis were used to identify correlations between cell populations, clinical measures, and patient outcomes.

RESULTS

Analysis revealed nine immune cell clusters that correlated with one or more clinical outcomes. On Days 1 and 3 postinjury, the abundance of immature neutrophil and classical monocytes exhibited a strong positive correlation with increased intensive care unit and hospital length of stay. Conversely, the abundance of CD4 T-cell subsets, namely Th17 cells, is associated with improved patient outcomes including decreased ventilator days (r = -0.76), hospital-acquired pneumonia (r = -0.69), and acute kidney injury (r = -0.73).

CONCLUSION

Here, we provide a comprehensive multitime point immunophenotyping analysis of whole blood from patients soon after traumatic injury to determine immune correlates of adverse outcomes. Our findings indicate that alterations in myeloid-origin cell types may contribute to immune dysfunction after injury. Conversely, the presence of effector T cell populations corresponds with decreased hospital length of stay and organ dysfunction. Overall, these data identify novel immune signatures following traumatic injury that support the view that monitoring of immune (sub)-populations may provide clinical decision-making support for at-risk patients early in their hospital course.

LEVEL OF EVIDENCE

Prognostic/Epidemiologic, Level IV.

Abstract 1633: Immunotherapy for malignant mesothelioma that combines a mesothelia-targeted immune-activating protein and CXCL12/CXCR4 blockade

Background and Purpose: There is a significant unmet need for new treatment strategies for malignant mesothelioma (MM). Despite relevant advances in many cancer treatment areas, including improvements in diagnosis, staging, and the clinical course of treated patients, MM remains a highly lethal disease. The purpose of this study is to develop a combination immunotherapy for MM, which involves a fusion protein to target and evoke a cellualr immune response to mesothelin (MSLN) and the blockade of CXCL12/CXCR4 pathway to mobilize cytotoxic effector cells into tumors.

Experimental Procedures: The efficacy of the MSLN targeted immune activating fusion protein (scFv-MtbHsp70), FDA-approved small molecule CXCR4 antagonist AMD3100 (plerixafor), and the combination were evaluated in two syngeneic and orthotopic murine models of MM in immune competent C57BL/6 mice. Mice received 4 intraperitoneal (i.p.) treatments from 7 days post i.p. injection of luciferase-expressing 40L and AE17 cells. Tumor growth was monitored by in vivo imaging of luciferase activity with an IVIS Spectrum. Survival time was calculated as life span from the day of tumor inoculation. In immunological studies, mice were sacrificed 4 weeks after tumor cell inoculation. Immune cells from spleens and tumors were labeled with antibodies against CD3, CD4, CD8, CD25 and Foxp3 antibodies, and examined by flow cytometry. Splenocytes were stimulated with MSLN and assessed for intracellular IFN-γ production by flow cytometry.

Results: In both murine mesothelioma models, the fusion protein scFv-MtbHsp70 alone delayed tumor growth and prolonged mouse survival, which was associated with increased tumor infiltration by CD3+CD8+ T cells. Treatment enhanced the cytotoxic function of tumor-specific CD3+CD8+ T cells by evoking dendritic cell activation as well as antigen presentation and cross presentation. AMD3100 alone reduced the proportion of CD4+CD25+Foxp3+ Treg cells in tumors and decreased PD-1 expression on CD3+CD8+ T cells. The combination of the fusion protein and AMD3100 further significantly slowed tumor growth and enhanced mouse survival while augmenting tumor-specific CD8+ T-cell immune responses and abrogating intratumoral immunosuppression.

Conclusion: Our findings demonstrated for the first time the synergistic effect of combination of MSLN-targeted immune-activating fusion protein scFv-MtbHsp70 and AMD3100 in treatment of MM in mice. This is a new therapeutic strategy which may significantly prolong survival of patients with this disease.

Citation Format: Huabiao Chen, Binghao Li, Yang Zeng, Patrick Reeves, Qiuyan Liu, Ann Sluder, Jeffrey Gelfand, Timothy Brauns, Mark Poznansky. Immunotherapy for malignant mesothelioma that combines a mesothelia-targeted immune-activating protein and CXCL12/CXCR4 blockade [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1633. doi:10.1158/1538-7445.AM2017-1633

Abstract 3649: Combination of mesothelin-targeted immune-activating fusion protein and anti-PD-L1 augments antitumor immunity and prolongs survival in murine model of ovarian cancer

Background and Purpose: Although immunotherapy as an adjuvant to surgery and chemotherapy has been investigated in ovarian cancer (OC) as a means of reducing tumor recurrence and improving survival, there remains a significant unmet need for combinatorial strategies to enhance the antitumor immune response. The purpose of this study was to develop a novel combination immunotherapy for OC, utilizing our novel fusion protein to target and generate a cellular immune response to mesothelin (MSLN) in conjunction with blockade of the PD-1/PD-L1 checkpoint to restore the function of cytotoxic T cells in order to enhance cancer control and prolong survival.

Experimental Procedures: Luciferase-expressing ID8 cells were employed to establish an intraperitoneal ovarian tumor model in immunocompetent C57BL/6 mice. The efficacies of the MSLN-targeted immune-activating fusion protein (VIC-008), αPD-L1, and the combination were evaluated. Mice received 4 intraperitoneal (i.p.) treatments of VIC-008 from day 7 post tumor inoculation weekly, and 6 treatments of αPD-L1 i.p. every other day from 4 weeks post inoculation. Tumor growth was monitored by in vivo imaging of luciferase activity. Survival time was calculated as life span from the day of tumor inoculation. In immunological studies, mice were sacrificed 7 weeks after tumor cell inoculation. Immune cells from lymph nodes, ascites and tumors were stained with antibodies against multiple immune cell markers and profiled by flow cytometry.

Results: VIC-008, αPD-L1 or combination treatment delayed tumor growth. The combination treatment resulted in the greatest prolongation in survival, followed by αPD-L1 treatment and then VIC-008 treatment. Improved survival was associated with increased levels of intratumoral CD3+CD8+ T cells (P&lt;0.0001). The combination treatment also reduced the proportion of CD4+CD25+Foxp3+ Treg cells (P&lt;0.0001) in the lymph nodes. An increased number of CD8+CD27+CD44+ memory T cells (P=0.0134) were observed in ascites in the combination treatment group. CD11b+CD11c+ dendritic cells were enriched in ascites in VIC-008 treatment (P=0.0019) and combination treatment groups (P=0.0010). More CD11c+CD38+ (M1) (P=0.0361) and fewer CD206+CD106+ (M2) (P=0.0285) macrophages were found in the tumors of the combination treatment group.

Conclusion: Our results suggest that, through activating dendritic cells and enhancing antigen presentation and cross-presentation, VIC-008 augments antitumor CD8+ T cell responses and facilitates generation of memory T cells when combined with PD-1/PD-L1 blockade, providing long-term antitumor effects. Our findings demonstrate for the first time a mechanistic rationale for combining VIC-008 and αPD-L1 in treatment of OC in mice, positioning this combination therapy as a potential promising new immunotherapeutic approach for OC.

Citation Format: Yang Zeng, Binghao Li, Qiuyan Liu, Patrick Reeves, Ann Sluder, Jeffrey Gelfand, Timothy Brauns, Mark Poznansky, Huabiao Chen. Combination of mesothelin-targeted immune-activating fusion protein and anti-PD-L1 augments antitumor immunity and prolongs survival in murine model of ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3649. doi:10.1158/1538-7445.AM2017-3649

VaxCelerate: the use of MTBhsp70-avidin as an adjuvant to rapidly generate self-assembling vaccines with biotinylated, antigen-specific peptides targeting emerging pathogens. (VAC6P.941)

Development of effective vaccines against emerging infectious diseases can take years to progress from pathogen isolation/identification to clinical approval. As a result, conventional approaches fail to produce field-ready vaccines before the EID has spread extensively. The VaxCelerate Project’s goal is to create a platform capable of generating and pre-clinically testing a new vaccine against specific pathogen targets in less than 120 days. A self-assembling vaccine, consisting of a fusion protein M. tuberculosis MTBhsp70 and avidin (MAV), is at the core of the approach. Mixing the MAV with biotinylated pathogen specific immunogenic peptides yields a self-assembled vaccine (SAV). To minimize the time required, we used a distributed R&D model involving experts in protein engineering, bioinformatics, peptide synthesis/design and GMP/GLP manufacturing and testing. This approach was first tested using ovalbumin in C57Bl/6 mice, Flu (H1N1) specific peptides, and ultimately a Lassa fever virus (LFV) specific vaccine in transgenic HLA DR3 mice. Using a GLP validated assay we demonstrated that the MAV assembled LFV induced significantly increased class II peptide specific interferon-CD4+ T cell responses in transgenic mice compared to peptide or MAV alone controls. The use of an identical design for each vaccine may facilitate accelerated regulatory review and by developing safety assessment tools that are more relevant to human vaccine responses than current preclinical models.

Safety of intramyocardial injection of autologous bone marrow cells to treat myocardial ischemia in pigs

OBJECTIVE

The purpose of this study is to determine the potential adverse consequences of intracardiac injections of bone marrow mononuclear cells (BMCs) to facilitate the revascularization of ischemic myocardium.

BACKGROUND

Bone marrow mononuclear cells are used to treat heart failure, though there are few studies that evaluated the safety of BMC transplantation for chronic myocardial ischemia.

METHODS

The pigs received coronary ameroid constrictors to induce chronic myocardial ischemia and left ventricular dysfunction. At 4 weeks, autologous BMCs were injected intramyocardially by Boston Scientific Stiletto catheter with low-dose (10(7) cells) or high-dose BMC (10(8)). Control animals received saline. Blood samples were collected for hematological and chemical indices, including cardiac enzyme levels at regular time intervals postinfarction. At 7 weeks, animals underwent electrophysiological study to evaluate the arrhythmic potential of transplanted BMC, followed by necropsy and histopathology.

RESULTS

No mortalities were associated with intramyocardial delivery of BMC or saline. At Day 0, the total creatine phosphokinase (CPK) was in the normal range in all groups. All groups had significant elevations in CPK after ameroid placement, with no significant differences between groups. At 7 weeks, CPK in all groups had returned to pretreatment levels. Electrophysiological assessment revealed that one control animal had an inducible arrhythmia. No arrhythmias were induced in low- or high-dose BMC-treated pigs. There were no histopathological changes associated with BMC injection.

CONCLUSION

This study showed, in a clinically relevant large-animal model, that catheter-based intramyocardial injection of autologous BMC into ischemic myocardium is safe.

Experience of HIV disease in a London District General Hospital

The aim of this paper is to describe and discuss the experience of HIV disease in Central Middlesex Hospital, London up to June 1993. A retrospective study of the total number of HIV-positive patients cared for was performed. In addition, prospectively collected data as part of local epidemiological surveillance from January 1987 to June 1993 on all HIV test requests was analysed. Between January 1987 and June 1993 3695 individuals were tested for HIV-1 antibody at Central Middlesex Hospital. Of these, 101 HIV-1 seropositive individuals were identified and have attended this District General Hospital. Seven HIV-1 seropositive individuals were identified from before December 1986. Sixty (56%) had acquired their infection heterosexually. Thirty-eight (35%) originated from the UK and 47 (44%) from sub-Saharan Africa; the remaining 23 (21%) originated from the rest of Europe, South America and the Caribbean. Thirty-four (31%) of the patient group developed AIDS during follow-up at the hospital and in 26 individuals AIDs developed within 2 months of their first positive HIV result. The mean survival of 20 patients after AIDS-defining diagnoses was 7 months 18 days. This unselected group of HIV-1 seropositive patients present late in the course of their HIV disease and survival following AIDS is poor.

Characterization and functional studies of rheumatoid synovial mast cells. Activation by secretagogues, anti-IgE, and a histamine-releasing lymphokine

Microscopic analysis of synovial specimens from 35 patients with rheumatoid arthritis (RA) and 7 patients with osteoarthritis revealed mast cell hyperplasia in perivascular regions, in fibrous interstitial areas, and clustered around the periphery of lymphoid aggregates. Metachromatic staining, immunofluorescence studies, and ultrastructural analysis revealed a single population of connective tissue-type mast cells with surface IgE receptors. Total extractable histamine of synovial tissue was 4.15 +/- 2.30 micrograms/gm (n = 8) for RA synovium and 0.53 +/- 0.23 microgram/gm (n = 7) for OA synovium. Mast cell secretion was assessed and specific release of histamine from RA synovial mast cells was observed following stimulation with anti-IgE (32.3%), compound 48/80 (40.1%), calcium ionophore A23187 (25.2%), and a partially purified lymphokine with histamine-releasing activity (23.9%).

Nonelectrolyte diffusion across lipid bilayer systems

The permeability coefficients of a homologous series of amides from formamide through valeramide have been measured in spherical bilayers prepared by the method described by Jung. They do not depend directly on the water:ether partition coefficient which increases regularly with chain length. Instead there is a minimum at acetamide. This has been ascribed to the effect of steric hindrance on diffusion within the bilayer which increases with solute molar volume. This factor is of the same magnitude, though opposite in sign to the effect of lipid solubility, thus accounting for the minimum. The resistance to passage across the interface has been compared to the resistance to diffusion within the membrane. As the solute chain length increases the interface becomes more important, until for valeramide it comprises about 90% of the total resistance. Interface resistance is also important in urea permeation, causing urea to permeate much more slowly than an amide of comparable size, after allowance is made for the difference in the water:ether partition coefficient. Amide permeation coefficients have been compared with relative liposome permeation data measured by the rate of liposome swelling. The ratios of the two measures of permeation vary between 3 and 16 for the homologous amides. The apparent enthalpy of liposome permeation has been measured and found to be in the neighborhood of 12 kcal mol-1 essentially independent of chain length. Comparison of the bilayer permeability coefficients with those of red cells shows that red cell permeation by the lipophilic solutes resembles that of the bilayers, whereas permeation by the hydrophilic solutes differs significantly.