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05 mg/kg cRGD-ZW800-1 for the intraoperative visualization of colon cancer. RESULTS cRGD-ZW800-1 appears safe, and exhibited rapid elimination into urine after a single low intravenous dose. Minimal invasive intraoperative visualization of colon cancer through full-thickness bowel wall was possible after an intravenous bolus injection of 0.05 mg/kg at least 2 h prior to surgery. Longer intervals between injection and imaging improved the tumor-to-background ratio. CONCLUSIONS cRGD-ZW800-1 enabled fluorescence imaging of colon cancer in both open and minimal invasive surgeries. read more Further development of cRGD-ZW800-1 for widespread use in cancer surgery may be warranted given the ubiquitous overexpression of various integrins on different types of tumors and their vasculature. Copyright ©2020, American Association for Cancer Research.PURPOSE Resistance to anti-PD1 based immune checkpoint blockade (ICB) remains a problem for the treatment of metastatic melanoma. Tumor cells as well as host myeloid cells can express the immune checkpoint ligand CD155 to regulate immune cell function. However, the effect of tumor CD155 on the immune context of human melanoma has not been well described. This observational study characterizes tumor CD155 ligand expression by metastatic melanoma tumors and correlates results with differences in immune cell features and response to ICB. EXPERIMENTAL DESIGN Pre-treatment tumor specimens, from 155 metastatic melanoma patients treated with ICB and from 50 patients treated with BRAF/MEK-directed-targeted therapy, were assessed for CD155 expression by immunohistochemistry. Intratumor T cell features were analysed using multiplex-immunohistofluorescence for CD8, PD1 and SOX10. Correlations were made between CD155 tumor level and bulk tumor RNA-seq results, as well as clinical RECIST response and progression-free survival. RESULTS High pretreatment CD155 tumor levels correlated with high parenchymal PD1+CD8+/CD8+ T cell ratios (PD1tR) and poor response to anti-PD1 therapy. In PD-L1 negative tumors, high CD155 tumor expression was associated with patients who had poor response to combination anti-PD1/CTLA4 therapy. CONCLUSIONS Our findings are the first to suggest that tumor CD155 supports an increase in the fraction of PD1+CD8+ T cells in anti-PD1 refractory melanoma tumors and, further, that targeting the CD155 pathway might improve response to anti-PD1 therapy for metastatic melanoma patients. Copyright ©2020, American Association for Cancer Research.PURPOSE With the increased prevalence in checkpoint therapy resistance, there remains a significant unmet need for additional therapies for relapsing or refractory cancer patients. We have developed FS222, a bispecific tetravalent antibody targeting CD137 and PD-L1 to induce T cell activation to eradicate tumours without the current toxicity and efficacy limitations seen clinically. EXPERIMENTAL DESIGN A bispecific antibody (FS222) was developed by engineering CD137 binding sites into the Fc region of a PD-L1 IgG1 mAb. T cell activation by FS222 was investigated using multiple in vitro assays. The anti-tumour efficacy, survival benefit, pharmacodynamics and liver pharmacology of a murine surrogate molecule were assessed in syngeneic mouse tumour models. Toxicology and the pharmacokinetic/pharmacodynamic profile of FS222 was investigated in a non-human primate dose-range finding study. RESULTS We demonstrated simultaneous binding of CD137 and PD-L1 and showed potent T cell activation across CD8+ T cell activation assays in a PD-L1-dependent manner with FS222. FS222 also activated T cells in a human primary mixed lymphocyte reaction assay, with greater potency than the monospecific mAb combination. FS222 showed no signs of liver toxicity up to 30 mg/kg in a non-human primate dose-range finding study. A surrogate molecule caused significant tumour growth inhibition and survival benefit, concomitant with CD8+ T cell activation, in CT26 and MC38 syngeneic mouse tumour models. CONCLUSIONS By targeting CD137 agonism to areas of PD-L1 expression, predominantly found in the tumour microenvironment, FS222 has the potential to leverage a focused, potent and safe immune response augmenting the PD-(L)1 axis blockade. Copyright ©2020, American Association for Cancer Research.As the SARS-CoV-2 (COVID19) pandemic spreads and the number of Bruton’s tyrosine kinase inhibitor (BTKi)-treated COVID19 affected patients grows, we must consider the pros and cons of BTKi discontinuation for our patients. In favor of BTKi continuation, BTK plays an active role in macrophage polarization. By modulating key transcription factors, BTK may regulate macrophage polarization downstream of classic M1 and M2 polarizing stimuli and mitigate the hyperinflammatory state associated with COVID19. In favor of BTKi discontinuation, we note a potentially increased risk of secondary infections or impaired humoral immunity. We hypothesize that the potential benefit of blunting a hyper-inflammatory response to SARS-CoV-2 through attenuation of M1 polarization outweighs the potential risk of impaired humoral immunity, not to mention the risk of rapid progression of B-cell malignancy following BTKi interruption. Based on this, we suggest continuing BTKi in patients with COVID19. Copyright ©2020, American Association for Cancer Research.Urinary tract infections (UTI) affect half of all women at least once during their lifetime. The rise in the numbers of extended-spectrum beta-lactamase-producing strains and the potential for carbapenem resistance within uropathogenic Escherichia coli (UPEC), the most common causative agent of UTI, create an urgent need for vaccine development. Intranasal immunization of mice with UPEC outer membrane iron receptors FyuA, Hma, IreA, and IutA, conjugated to cholera toxin, provides protection in the bladder or kidneys under conditions of challenge with UPEC strain CFT073 or strain 536. On the basis of these data, we sought to optimize the vaccination route (intramuscular, intranasal, or subcutaneous) in combination with adjuvants suitable for human use, including aluminum hydroxide gel (alum), monophosphoryl lipid A (MPLA), unmethylated CpG synthetic oligodeoxynucleotides (CpG), polyinosinicpolycytidylic acid (polyIC), and mutated heat-labile E. coli enterotoxin (dmLT). Mice intranasally vaccinated with dmLT-IutA and dmLT-Hma displayed significant reductions in bladder colonization (86-fold and 32-fold, respectively), with 40% to 42% of mice having no detectable CFU.