A Single Latent Plant Growth-Promoting Endophyte BH46 Enhances Houttuynia cordata Thunb. Yield and Quality.

Plant growth-promoting endophytes (PGPE) can effectively regulate plant growth and metabolism. The regulation is modulated by metabolic signals, and the resulting metabolites can have considerable effects on the plant yield and quality. Here, tissue culture Houttuynia cordata Thunb., was inoculated with Rhizobium sp. (BH46) to determine the effect of BH46 on H. cordata growth and metabolism, and elucidate associated regulatory mechanisms. The results revealed that BH46 metabolized indole-3-acetic acid and induced 1-aminocyclopropane-1-carboxylate deaminase to decrease ethylene metabolism. Host peroxidase synthesis MPK3/MPK6 genes were significantly downregulated, whereas eight genes associated with auxins, cytokinins, abscisic acid, jasmonic acid, and antioxidant enzymes were significantly upregulated. Eight genes associated with flavonoid biosynthesis were significantly upregulated, with the CPY75B1 gene regulating the production of rutin and quercitrin and the HCT gene directly regulating the production of chlorogenic acid. Therefore, BH46 influences metabolic signals in H. cordata to modulate its growth and metabolism, in turn, enhancing yield and quality of H. cordata.

Diagnostic accuracy of abdominal contrast-enhanced multi-slice spiral CT after oral diluted iodide in a time segment for gastrointestinal fistula in patients with severe acute pancreatitis.

PURPOSE: To evaluate the diagnostic accuracy of abdominal contrast-enhanced multi-slice spiral CT after oral diluted iodide in a time segment (post-ODI ACE-MSCT) for gastrointestinal fistula (GIF) in severe acute pancreatitis (SAP). MATERIALS AND METHODS: Patients with SAP who underwent both post-ODI ACE-MSCT and endoscopy/surgery from 2017 to 2023 were continuously retrospectively involved. Their demographic information and clinical features were recorded prospectively in an in-hospital database. Using endoscopy/surgery results as the reference standard, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of post-ODI ACE-MSCT for diagnosing GIF in SAP were calculated by a four-cell table. The consistency of the two diagnostic methods was evaluated by the Kappa test and McNemar's test. RESULTS: Using endoscopy/surgery as the reference standard, a total of 86 cases were divided into the GIF group (N = 52) and the non-GIF group (N = 34). Among the 52 cases of GIF, 88.5% (46/52) cases had a positive result and 11.5% (5/52) cases had a negative result of post-ODI ACE-MSCT for GIF. Among the 34 cases of non-GIF, 2.9% (1/34) case had a positive result and 97.1% (33/34) cases had a negative result of post-ODI ACE-MSCT for GIF. Post-ODI ACE-MSCT had a sensitivity of 88.5% (95% CI 75.9%-95.2%), a specificity of 97.1% (95% CI 82.9%-99.8%), a positive predictive value of 97.9% (95% CI 87.3%-99.9%), a negative predictive value of 84.6% (95% CI 68.8%-93.6%), and an accuracy of 91.9% (83.4%-96.4%). The kappa value was 0.834, and P < 0.001 by McNemar's test. There were no significant differences in diagnostic test characteristics between the two modalities. CONCLUSION: Post-ODI ACE-MSCT can diagnose GIF in SAP in a simple, noninvasive, and accurate way, and can provide earlier imaging evidence for clinical diagnosis and treatment.

Preclinical Characterization of Relatlimab, a Human LAG-3-Blocking Antibody, Alone or in Combination with Nivolumab.

Novel therapeutic approaches combining immune-checkpoint inhibitors are needed to improve clinical outcomes for patients with cancer. Lymphocyte-activation gene 3 (LAG-3) is an immune-checkpoint molecule that inhibits T-cell activity and antitumor immune responses, acting through an independent mechanism from that of programmed death-1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4). Here, we describe the development and preclinical characterization of relatlimab, a human antibody that binds to human LAG-3 with high affinity and specificity to block the interaction of LAG-3 with the ligands MHC II and fibrinogen-like protein-1, and to reverse LAG-3-mediated inhibition of T-cell function in vitro. Consistent with previous reports, in mouse models, the combined blockade of LAG-3 and PD-1 with surrogate antibodies resulted in enhanced antitumor activity greater than the individual blockade of either receptor. In toxicity studies in cynomolgus monkeys, relatlimab was generally well tolerated when combined with nivolumab. These results are consistent with findings from the RELATIVITY-047 phase II/III trial showing that relatlimab combined with nivolumab is a well-tolerated regimen that demonstrates superior progression-free survival compared with nivolumab monotherapy in patients with unresectable or metastatic melanoma.

Intrinsic Immunogenicity of Small Cell Lung Carcinoma Revealed by Its Cellular Plasticity.

Small cell lung carcinoma (SCLC) is highly mutated, yet durable response to immune checkpoint blockade (ICB) is rare. SCLC also exhibits cellular plasticity, which could influence its immunobiology. Here we discover that a distinct subset of SCLC uniquely upregulates MHC I, enriching for durable ICB benefit. In vitro modeling confirms epigenetic recovery of MHC I in SCLC following loss of neuroendocrine differentiation, which tracks with derepression of STING. Transient EZH2 inhibition expands these nonneuroendocrine cells, which display intrinsic innate immune signaling and basally restored antigen presentation. Consistent with these findings, murine nonneuroendocrine SCLC tumors are rejected in a syngeneic model, with clonal expansion of immunodominant effector CD8 T cells. Therapeutically, EZH2 inhibition followed by STING agonism enhances T-cell recognition and rejection of SCLC in mice. Together, these data identify MHC I as a novel biomarker of SCLC immune responsiveness and suggest novel immunotherapeutic approaches to co-opt SCLC's intrinsic immunogenicity. SIGNIFICANCE: SCLC is poorly immunogenic, displaying modest ICB responsiveness with rare durable activity. In profiling its plasticity, we uncover intrinsically immunogenic MHC Ihi subpopulations of nonneuroendocrine SCLC associated with durable ICB benefit. We also find that combined EZH2 inhibition and STING agonism uncovers this cell state, priming cells for immune rejection.This article is highlighted in the In This Issue feature, p. 1861.

A network pharmacology perspective for deciphering potential mechanisms of action of Solanum nigrum L. in bladder cancer.

BACKGROUND: Solanum nigrum L. decoction has been used as a folklore medicine in China to prevent the postoperative recurrence of bladder cancer (BC). However, there are no previous pharmacological studies on the protective mechanisms of this activity of the plant. Thus, this study aimed to perform a systematic analysis and to predict the potential action mechanisms underlying S. nigrum activity in BC based on network pharmacology. METHODS: Based on network pharmacology, the active ingredients of S. nigrum and the corresponding targets were identified using the Traditional Chinese Medicines for Systems Pharmacology Database and Analysis Platform database, and BC-related genes were screened using GeneCards and the Online Mendelian Inheritance in Man database. In addition, ingredient-target (I-T) and protein-protein interaction (PPI) networks were constructed using STRING and Cytoscape, Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted, and then the pathways directly related to BC were integrated manually to reveal the pharmacological mechanism underlying S. nigrum-medicated therapeutic effects in BC. RESULTS: Seven active herbal ingredients from 39 components of S. nigrum were identified, which shared 77 common target genes related to BC. I-T network analysis revealed that quercetin was associated with all targets and that NCOA2 was targeted by four ingredients. Besides, interleukin 6 had the highest degree value in the PPI network, indicating a hub role. A subsequent gene enrichment analysis yielded 86 significant GO terms and 89 significant pathways, implying that S. nigrum had therapeutic benefits in BC through multi-pathway effects, including the HIF-1, TNF, P53, MAPK, PI3K/Akt, apoptosis and bladder cancer pathway. CONCLUSIONS: S. nigrum may mediate pharmacological effects in BC through multi-target and various signaling pathways. Further validation is required experimentally. Network pharmacology approach provides a predicative novel strategy to reveal the holistic mechanism of action of herbs.

Antipeptide Immunocapture with In-Sample Calibration Curve Strategy for Sensitive and Robust LC-MS/MS Bioanalysis of Clinical Protein Biomarkers in Formalin-Fixed Paraffin-Embedded Tumor Tissues.

Despite huge promises, bioanalysis of protein biomarkers in formalin-fixed paraffin-embedded (FFPE) tissues by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for clinical applications is still very challenging. Here, we describe a sensitive and robust LC-MS/MS assay to quantify clinical protein biomarkers in FFPE tumor sections using automated antipeptide antibody immunocapture followed by in-sample calibration curve (ISCC) strategy with multiple isotopologue reaction monitoring (MIRM) technique. ISCC approach with MIRM of stable isotopically labeled (SIL) peptides eliminated the need for authentic matrices for external calibration curves, overcame the matrix effects, and validated the quantification range in each individual sample. Specifically, after deparaffinization, rehydration, antigen retrieval, and homogenization, the protein analytes in FFPE tumor tissues were spiked with a known concentration of one SIL peptide for each analyte, followed by trypsin digestion and antipeptide immunocapture enrichment prior to MIRM-ISCC-based LC-MS/MS analysis. This approach has been successfully used for sensitive quantification of programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) in 15 representative FFPE tumor samples from lung, colorectal, and head and neck cancer patients. Except for one sample, PD-L1 and PD-1 in all samples were quantifiable using this assay with concentrations of 27.85-798.43 (amol/µg protein) for PD-L1 and 16.96-129.89 (amol/µg protein) for PD-1. These results were generally in agreement with the immunohistochemistry (IHC) data but with some exceptions. This approach demonstrated the feasibility to quantify low abundant protein biomarkers in FFPE tissues with improved sensitivity, specificity, and robustness and showed great potential as an orthogonal analytical approach to IHC for clinical applications.

A Novel, Fully Human Anti-fucosyl-GM1 Antibody Demonstrates Potent In Vitro and In Vivo Antitumor Activity in Preclinical Models of Small Cell Lung Cancer.

Purpose: The ganglioside fucosyl-GM1 (FucGM1) is a tumor-associated antigen expressed in a large percentage of human small cell lung cancer (SCLC) tumors, but absent in most normal adult tissues, making it a promising target in immuno-oncology. This study was undertaken to evaluate the preclinical efficacy of BMS-986012, a novel, nonfucosylated, fully human IgG1 antibody that binds specifically to FucGM1.Experimental Design: The antitumor activity of BMS-986012 was evaluated in in vitro assays using SCLC cells and in mouse xenograft and syngeneic tumor models, with and without chemotherapeutic agents and checkpoint inhibitors.Results: BMS-986012 showed a high binding affinity for FcγRIIIa (CD16), which resulted in enhanced antibody-dependent cellular cytotoxicity (ADCC) against FucGM1-expressing tumor cell lines. BMS-986012-mediated tumor cell killing was also observed in complement-dependent cytotoxicity (CDC) and antibody-dependent cellular phagocytosis (ADCP) assays. In several mouse SCLC models, BMS-986012 demonstrated efficacy and was well tolerated. In the DMS79 xenograft model, tumor regression was achieved with BMS-986012 doses of 0.3 mg/kg and greater; antitumor activity was enhanced when BMS-986012 was combined with standard-of-care cisplatin or etoposide. In a syngeneic model, tumors derived from a genetically engineered model of SCLC were treated with BMS-986012 or anti-FucGM1 with a mouse IgG2a Fc and their responses evaluated; when BMS-986012 was combined with anti-PD-1 or anti-CD137 antibody, therapeutic responses significantly improved.Conclusions: Single-agent BMS-986012 demonstrated robust antitumor activity, with the addition of chemotherapeutic or immunomodulatory agents further inhibiting SCLC growth in the same models. These preclinical data supported evaluation of BMS-986012 in a phase I clinical trial of patients with relapsed, refractory SCLC. Clin Cancer Res; 24(20); 5178-89. ©2018 AACR.

Synthesis and Biologic Evaluation of a Novel 18F-Labeled Adnectin as a PET Radioligand for Imaging PD-L1 Expression.

The programmed death protein (PD-1) and its ligand (PD-L1) play critical roles in a checkpoint pathway cancer cells exploit to evade the immune system. A same-day PET imaging agent for measuring PD-L1 status in primary and metastatic lesions could be important for optimizing drug therapy. Herein, we have evaluated the tumor targeting of an anti-PD-L1 adnectin after 18F-fluorine labeling. Methods: An anti-PD-L1 adnectin was labeled with 18F in 2 steps. This synthesis featured fluorination of a novel prosthetic group, followed by a copper-free click conjugation to a modified adnectin to generate 18F-BMS-986192. 18F-BMS-986192 was evaluated in tumors using in vitro autoradiography and PET with mice bearing bilateral PD-L1-negative (PD-L1(-)) and PD-L1-positive (PD-L1(+)) subcutaneous tumors. 18F-BMS-986192 was evaluated for distribution, binding, and radiation dosimetry in a healthy cynomolgus monkey. Results:18F-BMS-986192 bound to human and cynomolgus PD-L1 with a dissociation constant of less than 35 pM, as measured by surface plasmon resonance. This adnectin was labeled with 18F to yield a PET radioligand for assessing PD-L1 expression in vivo. 18F-BMS-986192 bound to tumor tissues as a function of PD-L1 expression determined by immunohistochemistry. Radioligand binding was blocked in a dose-dependent manner. In vivo PET imaging clearly visualized PD-L1 expression in mice implanted with PD-L1(+), L2987 xenograft tumors. Two hours after dosing, a 3.5-fold-higher uptake (2.41 ± 0.29 vs. 0.82 ± 0.11 percentage injected dose per gram, P < 0.0001) was observed in L2987 than in control HT-29 (PD-L1(-)) tumors. Coadministration of 3 mg/kg ADX_5322_A02 anti-PD-L1 adnectin reduced tumor uptake at 2 h after injection by approximately 70%, whereas HT-29 uptake remained unchanged, demonstrating PD-L1-specific binding. Biodistribution in a nonhuman primate showed binding in the PD-L1-rich spleen, with rapid blood clearance through the kidneys and bladder. Binding in the PD-L1(+) spleen was reduced by coadministration of BMS-986192. Dosimetry estimates indicate that the kidney is the dose-limiting organ, with an estimated human absorbed dose of 2.20E-01 mSv/MBq. Conclusion:18F-BMS-986192 demonstrated the feasibility of noninvasively imaging the PD-L1 status of tumors by small-animal PET studies. Clinical studies with 18F-BMS-986192 are under way to measure PD-L1 expression in human tumors.

[Comparison of the Predictive Values of Eight Staging Systems for Primary Liver Cancer in Prognosis of Combined Hepatocellular-cholangiocellular Carcinoma Patients after Surgery].

OBJECTIVE: To compare the predictive values of eight staging systems for primary liver cancer in the prognosis of combined hepatocellular-cholangiocellular carcinoma (cHCC-CC) patients after surgery. METHODS: The clinical data of 54 cHCC-CC patients who underwent hepatectomy or liver transplantation from May 2005 to Augest 2013 in Chinese PLA General Hospital were collected. We evaluated the prognostic value of the Okuda staging system, Cancer of the Liver Italian Program (CLIP) score, French staging system, Barcelona Clinic Liver Cancer (BCLC) staging system, 7th edition of tumour-node-metastasis (TNM) staging system for hepatocellular carcinoma and intrahepatic cholangiocarcinoma (ICC), Japan Integrated Staging (JIS) score, and Chinese University Prognostic Index. The distribution, Kaplan-Meier method, Log-rank test, and area under a receiver operating characteristic curve were used to compare the prognosis-predicting ability of these different staging systems in 54 cHCC-CC patients after surgery. RESULTS: The TNM staging system for ICC and JIS score had a better distribution of cases. The 12-and 24-month survivals of the entire cohort were 65.5% and 56.3%, respectively. A Log-rank test showed that there was a significant difference existing in the cumulative survival rates of different stage patients when using TNM staging system for ICC (stage 1 vs. stage 2, P=0.012; stage 2 vs. stage 3-4, P=0.002), Okuda staging system (stage 1 vs. stage 2, P=0.025), and French staging system (stage A and stage B, P=0.045). The 12-and 24-month area under curve of TNM staging system for ICC, BCLC staging system, JIS score, and CLIP score were 0.836 and 0.847, 0.744 and 0.780, 0.723 and 0.764, and 0.710 and 0.786, respectively. CONCLUSION: The 7th edition of TNM staging system for ICC has superior prognostic value to other seven staging systems in cHCC-CC patients undergoing surgical treatment.

Auxiliary partial liver transplantation for acute liver failure using "high risk" grafts: Case report.

Acute liver failure (ALF) is a reversible disorder that is associated with an abrupt loss of hepatic mass, rapidly progressive encephalopathy and devastating complications. Despite its high mortality, an emergency liver transplantation nowadays forms an integral part in ALF management and has substantially improved the outcomes of ALF. Here, we report the case of a 32-year-old female patient who was admitted with grade IV hepatic encephalopathy (coma) following drug-induced ALF. We performed an emergency auxiliary partial orthotopic liver transplantation with a "high risk" graft (liver macrovesicular steatosis approximately 40%) from a living donor. The patient was discharged on postoperative day 57 with normal liver function. Weaning from immunosuppression was achieved 9 mo after transplantation. A follow-up using CT scan showed a remarkable increase in native liver volume and gradual loss of the graft. More than 6 years after the transplantation, the female now has a 4-year-old child and has returned to work full-time without any neurological sequelae.

Pure Laparoscopic Versus Open Liver Resection for Primary Liver Carcinoma in Elderly Patients: A Single-Center, Case-Matched Study.

Pure laparoscopic liver resection (PLLR) has been reported to be as safe and effective as open liver resection (OLR) for liver lesions, and it is associated with less intraoperative blood loss, shorter hospital stay, and lower complication rate. However, studies comparing PLLR with OLR in elderly patients were limited. The aim of this study was to analyze the short-term outcome of PLLR versus OLR for primary liver carcinoma (PLC) in elderly patients.Between January 2008 and October 2014, 30 consecutive elderly patients (≥70 years) who underwent PLLR for PLC were included into analysis. Sixty patients who received OLR for PLC during the same study period were also included as a case-matched control group. Patients were well matched in terms of age, sex, comorbid illness, Child Pugh class, American Society of Anesthesiologists grade, tumor size, tumor location, and extent of hepatectomy.No significant differences were observed with regard to patient preoperative baseline status, median tumor size (Group PLLR 4.0 cm vs Group OLR 5.0 cm, P = 0.125), tumor location, extent of hepatectomy, and operation time (Group PLLR 133 minutes vs Group OLR 170 minutes, P = 0.073). Compared with OLR, the PLLR group displayed a significantly less frequent Pringle maneuver application (10.0% vs 70.0%, P < 0.001), less blood loss (100 vs 300 mL; P < 0.001), shorter hospital stay (5 vs 10 days; P < 0.001), and lower total hospitalization cost ($9147.50 vs $10,867.10, P = 0.008). The postoperative complication rates were similar between groups (Group PLLR 10.0% vs Group OLR 16.7%; P = 0.532). There was no hospital mortality in both groups.PLLR for PLC is as safe and feasible as OLR, but with less blood loss, shorter hospital stay, and lower hospitalization cost for selected elderly patients.

Characterization of Organic Anion Transporter 2 (SLC22A7): A Highly Efficient Transporter for Creatinine and Species-Dependent Renal Tubular Expression.

The contribution of organic anion transporter OAT2 (SLC22A7) to the renal tubular secretion of creatinine and its exact localization in the kidney are reportedly controversial. In the present investigation, the transport of creatinine was assessed in human embryonic kidney (HEK) cells that stably expressed human OAT2 (OAT2-HEK) and isolated human renal proximal tubule cells (HRPTCs). The tubular localization of OAT2 in human, monkey, and rat kidney was characterized. The overexpression of OAT2 significantly enhanced the uptake of creatinine in OAT2-HEK cells. Under physiologic conditions (creatinine concentrations of 41.2 and 123.5 µM), the initial rate of OAT2-mediated creatinine transport was approximately 11-, 80-, and 80-fold higher than OCT2, multidrug and toxin extrusion protein (MATE)1, and MATE2K, respectively, resulting in approximately 37-, 1850-, and 80-fold increase of the intrinsic transport clearance when normalized to the transporter protein concentrations. Creatinine intracellular uptake and transcellular transport in HRPTCs were decreased in the presence of 50 µM bromosulfophthalein and 100 µM indomethacin, which inhibited OAT2 more potently than other known creatinine transporters, OCT2 and multidrug and toxin extrusion proteins MATE1 and MATE2K (IC50: 1.3 µM vs. > 100 µM and 2.1 µM vs. > 200 µM for bromosulfophthalein and indomethacin, respectively) Immunohistochemistry analysis showed that OAT2 protein was localized to both basolateral and apical membranes of human and cynomolgus monkey renal proximal tubules, but appeared only on the apical membrane of rat proximal tubules. Collectively, the findings revealed the important role of OAT2 in renal secretion and possible reabsorption of creatinine and suggested a molecular basis for potential species difference in the transporter handling of creatinine.

The effects of different preoperative biliary drainage methods on complications following pancreaticoduodenectomy.

The objective of this study was to investigate the effects of different preoperative biliary drainage (PBD) methods on complications in jaundiced patients following pancreaticoduodenectomy. We retrospectively analyzed 270 extrahepatic bile duct cancer patients who underwent pancreaticoduodenectomy. A total of 170 patients without PBD treatment were defined as the non-PBD group. According to different PBD methods, 45, 18, and 37 patients were classified into the percutaneous transhepatic biliary drainage (PTBD), endoscopic nasobiliary drainage (ENBD), and endoscopic retrograde biliary stent (ERBS) groups, respectively. Clinical characteristics and complications were compared among the 4 groups. Preoperative cholangitis occurred in 14 (8.2%) and 8 (21.6%) patients in the non-PBD and ERBS group, respectively (P = 0.04). Compared with the non-PBD group, delayed gastric emptying (DGE) and wound infection occurred significantly more often in the ERBS group. The incidence of severe complications was significantly lower in the PTBD group than the non-PBD group (P = 0.03). Postoperative hospital stay and complication rates were significantly higher in the ERBS group than the PTBD group. There were no significant differences in complications between ENBD and other groups. In conclusion, PTBD can improve surgical outcomes by reducing severe complication rate in jaundiced patients following pancreaticoduodenectomy. ERBS increased the rates of DGE and wound infection due to high incidence of cholangitis before operative intervention and should be avoided. ENBD carried no special effect on complications and needs further analysis.

Preoperative differential diagnosis between intrahepatic biliary cystadenoma and cystadenocarcinoma: a single-center experience.

AIM: To investigate preoperative differential diagnoses made between intrahepatic biliary cystadenoma and intrahepatic biliary cystadenocarcinoma. METHODS: A retrospective analysis of patient data was performed, which included 21 cases of intrahepatic biliary cystadenoma and 25 cases of intrahepatic biliary cystadenocarcinoma diagnosed between April 2003 and April 2013 at the General Hospital of PLA. Potential patients were excluded whose diagnoses were not confirmed pathologically. Basic information (including patient age and gender), clinical manifestation, duration of symptoms, serum assay results (including tumor markers and the results of liver function tests), radiological features and pathological results were collected. All patients were followed up. RESULTS: Preoperative levels of cancer antigen 125 (12.51 ± 9.31 vs 23.20 ± 21.86, P < 0.05) and carbohydrate antigen 19-9 (22.56 ± 26.30 vs 72.55 ± 115.99, P < 0.05) were higher in the cystadenocarcinoma subgroup than in the cystadenoma subgroup. There were no statistically significant differences in age or gender between the two groups, or in pre- or post-operative levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin (TBIL), and direct bilirubin (DBIL) between the two groups. However, eight of the 21 patients with cystadenoma and six of the 25 patients with cystadenocarcinoma had elevated levels of TBIL and DBIL. There were three cases in the cystadenoma subgroup and six cases in the cystadenocarcinoma subgroup with postoperative complications. CONCLUSION: Preoperative differential diagnosis relies on the integration of information, including clinical symptoms, laboratory findings and imaging results.

In vitro characterization of the anti-PD-1 antibody nivolumab, BMS-936558, and in vivo toxicology in non-human primates.

The programmed death-1 (PD-1) receptor serves as an immunologic checkpoint, limiting bystander tissue damage and preventing the development of autoimmunity during inflammatory responses. PD-1 is expressed by activated T cells and downmodulates T-cell effector functions upon binding to its ligands, PD-L1 and PD-L2, on antigen-presenting cells. In patients with cancer, the expression of PD-1 on tumor-infiltrating lymphocytes and its interaction with the ligands on tumor and immune cells in the tumor microenvironment undermine antitumor immunity and support its rationale for PD-1 blockade in cancer immunotherapy. This report details the development and characterization of nivolumab, a fully human IgG4 (S228P) anti-PD-1 receptor-blocking monoclonal antibody. Nivolumab binds to PD-1 with high affinity and specificity, and effectively inhibits the interaction between PD-1 and its ligands. In vitro assays demonstrated the ability of nivolumab to potently enhance T-cell responses and cytokine production in the mixed lymphocyte reaction and superantigen or cytomegalovirus stimulation assays. No in vitro antibody-dependent cell-mediated or complement-dependent cytotoxicity was observed with the use of nivolumab and activated T cells as targets. Nivolumab treatment did not induce adverse immune-related events when given to cynomolgus macaques at high concentrations, independent of circulating anti-nivolumab antibodies where observed. These data provide a comprehensive preclinical characterization of nivolumab, for which antitumor activity and safety have been demonstrated in human clinical trials in various solid tumors.

Antigenic targeting of the human mannose receptor induces tumor immunity.

Pattern recognition receptors are preferentially expressed on APCs allowing selective uptake of pathogens for the initiation of antimicrobial immunity. In particular, C-type lectin receptors, including the mannose receptor (MR), facilitate APC-mediated adsorptive endocytosis of microbial glyconjugates. We have investigated the potential of antigenic targeting to the MR as a means to induce Ag-specific humoral and cellular immunity. hMR transgenic (hMR Tg) mice were generated to allow specific targeting with the anti-hMR Ab, B11. We show that hMR targeting induced both humoral and cellular antigenic specific immunity. Immunization of hMR Tg mice with B11 mAbs induced potent humoral responses independent of adjuvant. Injection of hMR Tg mice with mouse anti-hMR Ab clone 19.2 elicited anti-Id-specific humoral immunity while non-Tg mice were unresponsive. B11-OVA fusion proteins (B11-OVA) were efficiently presented to OVA-specific CD4 and CD8 T cells in MR Tg, but not in non-Tg, mice. Effector differentiation of responding T cells in MR Tg mice was significantly enhanced with concomitant immunization with the TLR agonist, CpG. Administration of both CpG and B11-OVA to hMR Tg mice induced OVA-specific tumor immunity while WT mice remained unprotected. These studies support the clinical development of immunotherapeutic approaches in cancer using pattern recognition receptor targeting systems for the selective delivery of tumor Ags to APCs.

Characterization of endogenous betaine gamma-amino-n-butyric acid cotransporter glycoform and its hyperosmotic regulation in MDCK cells.

Increase in mRNA expression and transport activity of the betaine gamma-amino-n-butyric acid cotransporter (BGAT) in response to hyperosmolality has been previously shown in MDCK cells. However, the hyperosmolality-induced response of endogenous BGAT protein expression was not investigated in detail. We show two forms of endogenous BGAT immunoreactivity that are expressed in MDCK II cells. Both are sensitive to Peptide N-Glycosidase F (PNGase F), suggesting that they are N-glycosylated proteins. One band, about 75 kDa, is resistant to Endo H, while the other 55 kDa band is sensitive to it, suggesting that they are fully N-glycosylated mature form in the post-Golgi compartment and core-glycosylated immature form in the endoplasmic reticulum (ER), respectively. When treated with hyperosmolality, they are significantly increased. But the rate of BGAT processing, as assessed by the ratio of mature to immature form, is not increased, suggesting that hyperosmolality does not facilitate the export of BGAT from the ER to the secretory pathway. Surface biotinylation and confocal microscopy show that hyperosmolality significantly increases the amount of the mature form of BGAT on the basolateral membrane with a very small fraction on the apical membrane. We conclude that BGAT is an N-glycosylated protein with two glycoforms and endogenous BGAT synthesis rather than processing is involved in the adaptation to the hyperosmotic stress.

A novel human cancer vaccine elicits cellular responses to the tumor-associated antigen, human chorionic gonadotropin beta.

PURPOSE: The oncofetal antigen, human chorionic gonadotropin beta subunit (hCGbeta), is expressed by a number of carcinomas and is a prognostic indicator in renal, colorectal, bladder, and pancreatic cancers. We describe the development of a novel antibody-based dendritic cell (DC)-targeted cancer vaccine capable of eliciting cellular immune responses directed against hCGbeta. EXPERIMENTAL DESIGN: The tumor-associated antigen hCGbeta was coupled genetically to a human anti-DC antibody (B11). The resulting fusion protein (B11-hCGbeta) was evaluated for its ability to promote tumor antigen-specific cellular immune responses in a human in vitro model. Monocyte-derived human DCs from normal donors were exposed to purified B11-hCGbeta, activated with CD40 ligand, mixed with autologous lymphocytes, and tested for their ability to promote hCGbeta-specific proliferative and cytotoxic T-lymphocyte responses. RESULTS: B11-hCGbeta was found to be a soluble, well-defined, and readily purified product that specifically recognized the human mannose receptor via the B11 antibody portion of the fusion protein. B11-hCGbeta functionally promoted the uptake and processing of tumor antigen by DCs, which led to the generation of tumor-specific HLA class I and class II-restricted T-cell responses, including CTLs capable of killing human cancer cell lines expressing hCGbeta. CONCLUSIONS: Although other hCG vaccines have been shown to be capable of eliciting antibody responses to hCGbeta, this is the first time that cellular immune responses to hCGbeta have been induced by a vaccine in a human system. This DC-targeted hCGbeta vaccine holds promise for the management of a number of cancers and merits additional clinical development.

Organic solutes rescue the functional defect in delta F508 cystic fibrosis transmembrane conductance regulator.

The most common defect in cystic fibrosis, deletion of phenylalanine from position 508 of the cystic fibrosis transmembrane conductance regulator (Delta F508 CFTR), decreases the trafficking of this protein to the cell surface membrane. Previous studies have shown that low temperature and high concentrations of glycerol or trimethylamine N-oxide can partially counteract the processing defect of Delta F508 CFTR. The present study investigates whether physiologically relevant concentrations of organic solutes, accumulated by cotransporter proteins, can rescue the misprocessing of Delta F508 CFTR. Myoinositol alone or myoinositol, betaine, and taurine given sequentially increased the processing of core-glycosylated, endoplasmic reticulum-arrested Delta F508 CFTR into the fully glycosylated form of CFTR in IB3 cells or NIH 3T3 cells stably expressing Delta F508 CFTR. Pulse-chase experiments using transiently transfected COS7 cells demonstrated that organic solutes also increased the processing of the core-glycosylated form of green fluorescent protein-Delta F508 CFTR. Moreover, the prolonged half-life of the complex-glycosylated form of GFP-Delta F508 CFTR suggests that this treatment stabilized the mature form of the protein. In vitro studies of purified NBD1 stability and aggregation showed that myoinositol stabilized both the Delta F508 and wild type CFTR and inhibited Delta F508 misfolding. Most significantly, treatment of CF bronchial airway cells with these transportable organic solutes restores cAMP-stimulated single channel activity of both CFTR and outwardly rectifying chloride channel in the cell surface membrane and also restores a forskolin-stimulated macroscopic 36Cl- efflux. We conclude that organic solutes can repair CFTR functions by enhancing the processing of Delta F508 CFTR to the plasma membrane by stabilizing the complex-glycosylated form of Delta F508 CFTR.

The ClC-5 knockout mouse model of Dent's disease has renal hypercalciuria and increased bone turnover.

Dent's disease is a nephrolithiasis disorder associated with hypercalciuria and low molecular weight proteinuria that is caused by mutations in the voltage-gated chloride channel ClC-5. Because the exact cause of hypercalciuria in this disease is unknown and could come from a renal, intestinal, or bone origin, we have investigated overall calcium handling in the ClC-5 knockout mouse (ClC-5 KO). On a high calcium diet, ClC-5 KO mice had elevated serum 1alpha,25-dihydroxyvitamin D3 (1alpha,25D3), alkaline phosphatase (AP), osteocalcin (OC), and urinary deoxypyridinoline (DPD), but serum parathyroid hormone (PTH), calcium, and intestinal calcium uptake was similar to that of wild-type (WT) mice. A 30-fold decrease in dietary calcium intake caused elevation of serum PTH and urinary cyclic adenosine monophosphate in ClC-5 KO mice and decreased the renal calcium excretion, which still remained 2-fold above that of WT mice. On this low calcium diet, both groups of mice had the same serum 1alpha,25D3, with similar increments in intestinal calcium absorption, serum AP, OC, and urinary DPD. These data indicate that the hypercalciuria in the ClC-5 KO mice on low and high calcium diets is of bone and renal origin and is not caused by increased intestinal calcium absorption, despite an elevated serum 1alpha,25D3. These mice data suggest that young patients with this disease may have a propensity for altered bone homeostasis that should be monitored clinically.