A receptor-binding domain-based nanoparticle vaccine elicits durable neutralizing antibody responses against SARS-CoV-2 and variants of concern

Numerous vaccines have been developed to address the current COVID-19 pandemic, but safety, cross-neutralizing efficacy, and long-term protectivity of currently approved vaccines are still important issues. In this study, we developed a subunit vaccine, ASD254, by using a nanoparticle vaccine platform to encapsulate the SARS-CoV-2 spike receptor-binding domain (RBD) protein. As compared with the aluminum-adjuvant RBD vaccine, ASD254 induced higher titers of RBD-specific antibodies and generated 10- to 30-fold more neutralizing antibodies. Mice vaccinated with ASD254 showed protective immune responses against SARS-CoV-2 challenge, with undetectable infectious viral loads and reduced typical lesions in lung. Besides, neutralizing antibodies in vaccinated mice lasted for at least one year and were effective against various SARS-CoV-2 variants of concern, including B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta), and B.1.1.529 (Omicron). Furthermore, particle size, polydispersity index, and zeta-potential of ASD254 remained stable after 8-month storage at 4°C. Thus, ASD254 is a promising nanoparticle vaccine with good immunogenicity and stability to be developed as an effective vaccine option in controlling upcoming waves of COVID-19.

Development of AAV-delivered broadly neutralizing anti-human ACE2 antibodies against SARS-CoV-2 variants

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in the emergence of new variants that are resistant to existing vaccines and therapeutic antibodies, has raised the need for novel strategies to combat the persistent global COVID-19 epidemic. In this study, a monoclonal anti-human angiotensin-converting enzyme 2 (hACE2) antibody, ch2H2, was isolated and humanized to block the viral receptor-binding domain (RBD) binding to hACE2, the major entry receptor of SARS-CoV-2. This antibody targets the RBD-binding site on the N terminus of hACE2 and has a high binding affinity to outcompete the RBD. In vitro, ch2H2 antibody showed potent inhibitory activity against multiple SARS-CoV-2 variants, including the most antigenically drifted and immune-evading variant Omicron. In vivo, adeno-associated virus (AAV)-mediated delivery enabled a sustained expression of monoclonal antibody (mAb) ch2H2, generating a high concentration of antibodies in mice. A single administration of AAV-delivered mAb ch2H2 significantly reduced viral RNA load and infectious virions and mitigated pulmonary pathological changes in mice challenged with SARS-CoV-2 Omicron BA.5 subvariant. Collectively, the results suggest that AAV-delivered hACE2-blocking antibody provides a promising approach for developing broad-spectrum antivirals against SARS-CoV-2 and potentially other hACE2-dependent pathogens that may emerge in the future.

[Efficacy and safety of neoadjuvant chemotherapy combined with PD-1 antibody for esophageal squamous cell carcinoma in the real world]

Objective: To evaluate the efficacy and safety of neoadjuvant chemotherapy combined with programmed death-1 (PD-1) antibody in operable, borderline or potentially resectable locally advanced esophageal squamous cell carcinoma(ESCC) in the real world. Methods: The study retrospectively analyzed 28 patients with operable or potentially resectable locally advanced ESCC patients treated with preoperative chemotherapy combined with PD-1 inhibitor in Nanjing Drum Tower Hospital, Affiliated Hospital of Nanjing University Medical School from April 2020 to March 2021. According to the clinical TNM staging system of the 8th edition of the American Joint Committee on Cancer, there were 1, 15, 10, 1 and 1 case of stage Ⅱ, Ⅲ, ⅣA, ⅣB and unknown stage respectively. The treatment was two cycle of dual drug chemotherapy regimen including taxane plus platinum or fluorouracil combined with PD-1 antibody followed by tumor response assessment and surgery if the patient was eligible for resection. Results: Of the 28 patients, 1, 2, 3 and 4 cycles of chemotherapy combined with PD-1 antibody treatment completed in 1, 21, 5, and 1 patient, respectively. Objective response rate (ORR) was 71.4% (20/28), and disease control rate (DCR) was 100% (28/28). The incidence of adverse events exceeding grade 3 levels was 21.4% (6/28), including 3 neutropenia, 1 leukopenia, 1 thrombocytopenia and 1 immune hepatitis. There was no treatment-related death. Of the 23 patients underwent surgery, R0 resection rate was 87.0% (20/23), 13 patients had down staged to the T1-2N0M0 I stage, the pCR rate was 17.3% (4/23), and the pCR rate of primary tumor was 21.7% (5/23). Four patients received definitive chemoradiotherapy. One patient rejected surgery and other treatment after achieved PR response. Conclusion: Neoadjuvant chemotherapy combined PD-1 inhibitor is safe and has high efficacy in operable, borderline or potentially resectable locally advanced ESCC, and it is a promising regimen.

A booster dose of Delta × Omicron hybrid mRNA vaccine produced broadly neutralizing antibody against Omicron and other SARS-CoV-2 variants

BACKGROUND

With the continuous emergence of new SARS-CoV-2 variants that feature increased transmission and immune escape, there is an urgent demand for a better vaccine design that will provide broader neutralizing efficacy.

METHODS

We report an mRNA-based vaccine using an engineered "hybrid" receptor binding domain (RBD) that contains all 16 point-mutations shown in the currently prevailing Omicron and Delta variants.

RESULTS

A booster dose of hybrid vaccine in mice previously immunized with wild-type RBD vaccine induced high titers of broadly neutralizing antibodies against all tested SARS-CoV-2 variants of concern (VOCs). In naïve mice, hybrid vaccine generated strong Omicron-specific neutralizing antibodies as well as low but significant titers against other VOCs. Hybrid vaccine also elicited CD8+/IFN-γ+ T cell responses against a conserved T cell epitope present in wild type and all VOCs.

CONCLUSIONS

These results demonstrate that inclusion of different antigenic mutations from various SARS-CoV-2 variants is a feasible approach to develop cross-protective vaccines.

Structure-guided antibody cocktail for prevention and treatment of COVID-19

Development of effective therapeutics for mitigating the COVID-19 pandemic is a pressing global need. Neutralizing antibodies are known to be effective antivirals, as they can be rapidly deployed to prevent disease progression and can accelerate patient recovery without the need for fully developed host immunity. Here, we report the generation and characterization of a series of chimeric antibodies against the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Some of these antibodies exhibit exceptionally potent neutralization activities in vitro and in vivo, and the most potent of our antibodies target three distinct non-overlapping epitopes within the RBD. Cryo-electron microscopy analyses of two highly potent antibodies in complex with the SARS-CoV-2 spike protein suggested they may be particularly useful when combined in a cocktail therapy. The efficacy of this antibody cocktail was confirmed in SARS-CoV-2-infected mouse and hamster models as prophylactic and post-infection treatments. With the emergence of more contagious variants of SARS-CoV-2, cocktail antibody therapies hold great promise to control disease and prevent drug resistance.

Effective approaches to mitigate the COVID-19 pandemic are a pressing global need. One promising strategy is to combine neutralizing antibodies that can reduce viral load to prevent disease progression and accelerate patient recovery. However, the current supply of therapeutic antibodies for COVID-19 is insufficient to fill the enormous demand, and escape mutants may compromise the utility of existing drugs. Thus, there is an urgent worldwide need to develop highly potent neutralizing antibody cocktails. We generated a series of chimeric antibodies against the receptor-binding domain (RBD) of SARS-CoV-2 spike protein, which potently neutralize authentic SARS-CoV-2 infection according to the plaque reduction neutralization test (PRNT) and pseudovirus-based inhibition assay. These antibodies can be classified into three distinct groups based on their targets within the receptor-binding motif. Cryo-electron microscopy structural analyses of two representative receptor-binding domain-chimeric antibodies in complex with the SARS-CoV-2 spike protein further revealed two sets of non-overlapping epitopes, suggesting the potential for their combination in a therapeutic antibody cocktail. The prophylactic and therapeutic effects of these antibodies and their combination were demonstrated in SARS-CoV-2-infected mouse and hamster models. Thus, our potent neutralizing antibody cocktail has strong potential for development as an effective therapeutic drug to prevent and treat SARS-CoV-2 infection.

First Determination of Glycidyl Ester Species in Edible Oils by Reverse-Phase Ultra-Performance Liquid Chromatography Coupled with an Evaporative Light-Scattering Detector

In this work, a new ultra-performance liquid chromatograph-evaporative light-scattering detector (UPLC-ELSD) method for quantitation of glycidyl esters (GE) contents in edible oils is presented. The method features complete separation of five GE species within 20 min by a C18 column and gradient elution with a mobile phase consisting of 85% and 2.5% methanol aqueous solutions. The coefficients of regression (R²) were all ≥0.9999 for the linear-quadratic regression curves of GE species in a concentration range of 5~80 μg/mL. The intraday and interday recoveries (%) of GE species in solvent were in a range of 81.3~107.3%, and the intraday and interday coefficients of variation (CVs, %) were all ≤8.6%. The average recovery (%) of GE species spiked in extra-virgin olive oil samples ranged from 88.3~107.8% and the intermediate precision (CV, %) of ≤14% indicated acceptable accuracy and precision. The method exhibited limit of quantification (LOQ) for each GE species (0.6 μg glycidol equivalents/g oil). The method was applied to determine GE concentrations of six commercial oil samples, and total glycidol equivalents were consistent with data obtained by GC-MS method. This UPLC-ELSD method could be adopted for precursory screening and research purposes to improve food safety when MS detectors are unavailable.

CpG-adjuvanted stable prefusion SARS-CoV-2 spike protein protected hamsters from SARS-CoV-2 challenge

The COVID-19 pandemic presents an unprecedented challenge to global public health. Rapid development and deployment of safe and effective vaccines are imperative to control the pandemic. In the current study, we applied our adjuvanted stable prefusion SARS-CoV-2 spike (S-2P)-based vaccine, MVC-COV1901, to hamster models to demonstrate immunogenicity and protection from virus challenge. Golden Syrian hamsters immunized intramuscularly with two injections of 1 µg or 5 µg of S-2P adjuvanted with CpG 1018 and aluminum hydroxide (alum) were challenged intranasally with SARS-CoV-2. Prior to virus challenge, the vaccine induced high levels of neutralizing antibodies with 10,000-fold higher IgG level and an average of 50-fold higher pseudovirus neutralizing titers in either dose groups than vehicle or adjuvant control groups. Six days after infection, vaccinated hamsters did not display any weight loss associated with infection and had significantly reduced lung pathology and most importantly, lung viral load levels were reduced to lower than detection limit compared to unvaccinated animals. Vaccination with either 1 μg or 5 μg of adjuvanted S-2P produced comparable immunogenicity and protection from infection. This study builds upon our previous results to support the clinical development of MVC-COV1901 as a safe, highly immunogenic, and protective COVID-19 vaccine.

Furin Inhibitors Block SARS-CoV-2 Spike Protein Cleavage to Suppress Virus Production and Cytopathic Effects

Development of specific antiviral agents is an urgent unmet need for SARS-coronavirus 2 (SARS-CoV-2) infection. This study focuses on host proteases that proteolytically activate the SARS-CoV-2 spike protein, critical for its fusion after binding to angiotensin-converting enzyme 2 (ACE2), as antiviral targets. We first validate cleavage at a putative furin substrate motif at SARS-CoV-2 spikes by expressing it in VeroE6 cells and find prominent syncytium formation. Cleavage and the syncytium are abolished by treatment with the furin inhibitors decanoyl-RVKR-chloromethylketone (CMK) and naphthofluorescein, but not by the transmembrane protease serine 2 (TMPRSS2) inhibitor camostat. CMK and naphthofluorescein show antiviral effects on SARS-CoV-2-infected cells by decreasing virus production and cytopathic effects. Further analysis reveals that, similar to camostat, CMK blocks virus entry, but it further suppresses cleavage of spikes and the syncytium. Naphthofluorescein acts primarily by suppressing viral RNA transcription. Therefore, furin inhibitors may be promising antiviral agents for prevention and treatment of SARS-CoV-2 infection.

•

The furin cleavage site in the SARS-CoV-2 spike protein mediates syncytium formation

•

The SARS-CoV-2 spike-mediated syncytium is suppressed by specific furin inhibitors

•

Furin inhibitors block SARS-CoV-2 virus entry and virus replication

•

Furin inhibitors are potential antiviral agents for SARS-CoV-2 infection and pathogenesis

Structure-activity relationship (SAR) studies of synthetic glycogen synthase kinase-3β inhibitors: A critical review

Glycogen Synthase Kinase-3 (GSK-3) is a constitutively dynamic, omnipresent serine/threonine protein kinase regularly called as a "multitasking kinase" due to its pliable function in diverse signaling pathways. It exists in two isoforms i.e., GSK-3α and GSK-3β. Inhibition of GSK-3 may be useful in curing various diseases such as Alzheimer's disease, type II diabetes, mood disorders, cancers, chronic inflammatory agents, stroke, bipolar disorders and so on, but the approach poses significant challenges. Lithium was the first GSK-3β inhibitor to be used for therapeutic outcome and has been effectively used for many years. In recent years, a large number of structurally diverse potent GSK-3β inhibitors are reported. The present review focuses on the recent developments in the area of medicinal chemistry to explore the diverse chemical structures of potent GSK-3β inhibitors and also describes its structure-activity relationships (SAR) and molecular binding interactions of favorable applicability in various diseases.

Combination of radiation and interleukin 12 eradicates large orthotopic hepatocellular carcinoma through immunomodulation of tumor microenvironment

Immunotherapies have shown promising results in certain cancer patients. For hepatocellular carcinoma (HCC), the multiplicity of an immunotolerant microenvironment within both the tumor, and the liver per se may limit the efficacy of cancer immunotherapies. Since radiation induces immunogenic cell death and inflammatory reactions within the tumor microenvironment, we hypothesized that a combination therapy of radiation and lasting local immunostimulating agents, achieved by intratumoral injection of an adenoviral vector encoding interleukin 12, may reverse the immunotolerant microenvironment within a well-established orthotopic HCC toward a state favorable for inducing antitumor immunities. Our data showed that radiation and IL-12 combination therapy (RT/IL-12) led to dramatic tumor regression in animals bearing large subcutaneous or orthotopic HCC, induced systemic effect against distant tumor, and significantly prolonged survival. Radiation monotherapy induced tumor regression at early times but afterwards most tumors regained exponential growth, while IL-12 monotherapy only delayed tumor growth. Mechanistic studies revealed that RT/IL-12 increased expression of MHC class II and co-stimulatory molecules CD40 and CD86 on tumor-infiltrating dendritic cells, suggesting an improvement of their antigen presentation activity. RT/IL-12 also significantly reduced accumulation of tumor-infiltrating myeloid-derived suppressor cells (MDSCs) and impaired their suppressive functions by reducing production of reactive oxygen species. Accordingly, tumor-infiltrating CD8⁺ T cells and NK cells were significantly activated toward the antitumor phenotype, as revealed by increased expression of CD107a and TNF-α. Together, our data showed that RT/IL-12 treatment could reset the intratumoral immunotolerant state and stimulate activation of antitumor cellular immunity that is capable of eliminating large established HCC tumors.

Abstract 609: Neutrophils play a critical role in mediating antitumor activity of a combination therapy of radiation and immunotherapy

The goal of cancer immunotherapy is to elicit robust tumor-specific immune responses that can generate durable tumor regression and/or eradication. Recent clinical trials using immune checkpoint blockades specific to programmed cell death-1/ligand-1 (PD-1/PD-L1) have shown durable clinical responses in various cancer types but benefit only a small portion of patients. We previously demonstrated that combination of radiation and immunotherapy of interleukin 12 (IL-12) and granulocyte macrophage colony-stimulator factor (GM-CSF) greatly improved the therapeutic efficacy than either single therapy alone. In analysis of the tumor-infiltrating leukocytes post combination therapy, we found that the number of CD11b+F4/80-/Ly6G+ neutrophils were greatly increased. In this study, we characterized these tumor-associated neutrophils (TANs) before and after treatment and investigated their role in mediating the antitumor activity of the combination therapy. We isolated TANs from the regressing tumors and demonstrated that these TANs were impaired in their immunosuppressive activities. Flowcytometric analysis revealed that several co-stimulatory molecules, including class II major histocompatibility complex, CD40 and CD86, were increased on these TANs. Accordingly, these TANs gained the ability to stimulate T cell proliferation. Antibody-depletion experiments showed that TANs were required for tumor regression in RT/12GM combination therapy. Together, our data demonstrate that combination of radiotherapy and IL-12/GM-CSF improved antitumor immunity through enhancing antigen presentation activity and reduced immunosuppressive functions of TANs.

Citation Format: Mi-Hua Tao, Chia-Jen Wu, Yi-Ting Tsai, Ping-Yi Wu. Neutrophils play a critical role in mediating antitumor activity of a combination therapy of radiation and immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 609.

The Roles of Tumor-associated Neutrophils in Colorectal Cancer Treated with Different Combinatorial Immunotherapies

Cancer immunotherapy can elicit robust tumor-specific immune responses that can generate durable tumor regression or eradication. Immune checkpoint blockade specific to programmed death-1/ligand-1 (PD1/PDL1) have shown durable clinical responses in various cancer types but benefit only a small portion of patients. Interleukin 12 (IL-12) and granulocyte macrophage colony-stimulator factor (GM-CSF) have shown potent antitumor activities through activating innate and adaptive immunities, and reprogramming tumor-promoting myeloid cells from immune-suppressive to immune-active phenotypes. In this study, we showed the effect of radiation, which increased release of tumor antigens so that augment the efficacy of immunotherapy, in combination with IL-12/GM-CSF (RT/12GM) or anti-PDL1 antibody (RT/PDL1) on TAN in advanced 14-day-CT26 colorectoral cancer. We found that both combination treatment significantly suppressed tumor growth, only RT/12GM but not RT/PDL1 can cure mice; radiation or immunotherapy alone single therapies were much less effective. Mechanistic analysis showed that RT/12GM, but not RT/PDL1, greatly increased accumulation of TAN. These TANs were not only impaired in their suppressive activities, but also able to induce T cell proliferation, in accordance with their increased expressions of MHC class I and II, CD40 and CD86, indicating they presented in a status with higher Ag presentation ability. Antibody depletion experiments showed that TAN was required for tumor regression in RT/12GM therapy. Together, our data demonstrate that combination of radiotherapy and IL-12/GM-CSF improved antitumor immunity through enhancing Ag presentation activity and reducing immunosuppressive functions of TAN.

Induction of Virus-specific Immune Tolerance in A Chronic Hepatitis B Virus Mouse Model

Hepatitis B virus (HBV) infection causes severe public health problem. There are estimated 250 million people being chronically infected by HBV and are at an increased risk of developing end-stage liver diseases, such as cirrhosis and hepatocellular carcinoma. It is well recognized that the chronicity of HBV infection is due to the impaired immune responses to HBV and thus not able to eliminate HBV from the infected hepatocytes. However, the immune mechanisms that lead to immune tolerance and HBV persistence have not been understood. A challenging question for HBV studies is lack of appropriate animal models due to the narrow host range of HBV. To address this challenge, we created a chronic HBV infection model in immunocompetent mice by transduction of adeno-associated virus serotype 8 (AAV8) vector which carries and these mice was transduced with carrying a replication-defective HBV genome with two point mutations in the polymerase(AAV/HBVp−). We showed that mice transduced with AAV/HBVp− produced HBV RNA and proteins, including serum HBV surface antigen and HBV e antigen as well as HBV core protein. The high levels of HBV RNA and proteins sustained for at least 1 year post AAV transduction. Viral transcripts and proteins were detected in the livers of the AAV-injected mice but not in other organs. DNA immunization of these AAV/HBVp− transduced mice failed to induce HBV-specific humoral and cellular immune responses, suggesting these mice developed immune tolerance toward HBV. Thus, the AAV/HBVp− transduced mouse model recapitulates many virological and immunological characteristics of chronic HBV in humans. This animal model could be useful for the development of new treatments and immune-based therapies for chronic HBV infections.

Efficacy of combining radiotherapy and immunotherapy for metastatic colorectal cancer and the modulation of tumor microenvironment

Immune checkpoint blockade antibodies specific to programed death-1/ligand-1 (PD-1/PD-L1) shows durable clinical responses in various cancers but benefit only to a small portion of patients. The failure of immunotherapy is likely due to the complex network of immunosuppressive mechanisms present in advanced tumors. Radiation (RT) modifies tumor microenvironment and causes tumor antigen release, and thus augment efficacy of immunotherapy. Interleukin 12 (IL-12) and granulocyte macrophage colony-stimulator factor (GM-CSF) have shown potent antitumor activities through activating innate and adaptive immunities, as well as reprogramming myeloid cells to a phenotype that favors immune activation. The aim of this project is to compare the therapeutic efficacy of two types of combination therapy: RT combined with IL-12/GM-CSF (RT/12GM) versus RT combined with anti-PD-L1 antibody (RT/PD-L1), and to dissect the molecular mechanisms of the antitumor responses. Our data showed that RT/12GM led to tumor regression in a majority of mice with large established tumors and suppressed liver metastasis, while RT/PD-L1 could only suppress primary tumors but not metastatic tumor. Mechanistic analysis showed that RT/12GM was superior to RT/PD-L1 in inducing accumulation of CD8+ T cells in tumor and in augmenting both NK and CD8+ T cells cytotoxicity in tumor and liver. Interestingly, RT/12GM also induced infiltration of tumor-associated neutrophils (TAN) and impaired their immunosuppressive functions. Depletion experiments showed that both CD8+ T cell and TAN were required for tumor regression in RT/12GM. Together, our results demonstrate that RT/12GM represent a powerful alternative therapy against both primary and metastatic tumors.

Radiation improved IL-21 cancer immunotherapy

Interleukin-21 is a pleiotropic cytokine which has shown promising antitumor activities in several preclinical models but the response rate in phase I–II clinical studies has been disappointing. Therefore, the optimal usage of IL-21 as an effective therapy against cancers remains to be studied. Radiotherapy, a well establish treatment modality for cancers, has shown its potential in immunogenic modulation by stimulating immune cell phagocytosis and inducing local tumor-associated antigens releasing. We hypothesize that a synergistic antitumor effect could be achieved by combining IL-21 with radiation through releasing neoantigens and amplifying adaptive antitumor immune responses against both primary and metastatic tumors. We treated mice bearing large established tumors with radiation, IL-21 or a combination of radiation and IL-21. Mice treated with radiation alone showed delayed tumor growth, while IL-21 treatment had very little effect. In contrast, a synergistic antitumor effect was achieved in the combination group, which not only led to complete tumor regression of primary tumors, but also significantly suppressed the growth of distant, untreated metastatic tumors. Mechanistic analysis revealed that combination therapy increased accumulation of tumor-infiltrating CD8+ T cells which showed enhanced functional activities, marked by increased expression of CD107a, IFN-γ and TNF-α. Moreover, mice that had been cured by the combination therapy developed memory responses against the subsequent tumor re-challenge. Our results demonstrate that combination of IL-21 and radiation has potent antitumor activity against both primary and metastatic tumors and could open a new perspective for cancer therapy.

Combination of IL-12 and radiotherapy induced regression of large orthotopic liver cancers through modulation of immune cells in tumor microenvironment

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide with few therapeutic options. Radiation is wildly used for cancer treatment, but local relapse often occurs. Interleukin 12 (IL-12) has potent antitumor activities by activating natural killer cells (NK) and CD8+ T cells, reprogramming myeloid cells to an immune active phenotype, and inhibiting new blood vessel formation. We hypothesized that combined radiation and IL-12 treatment may change tumor suppressive microenvironment and induce antitumor immune responses. Our data showed that only combination of radiation and intratumoral injection of adenovirus encoding IL-12 (Ad/IL-12) led to tumor regression in mice with large subcutaneous or orthotopic HCC, and significantly prolonged their survival. Mechanistic studies revealed that combination therapy enhanced antigen (Ag) presentation ability of DCs by increasing MHC class II, CD40 and CD86 expression. Combination therapy also significantly reduced numbers of tumor-infiltrating myeloid-derived suppressor cells (MDSCs) and impaired their suppressive functions by reducing reactive oxygen species (ROS) production. Accordingly, combination therapy significantly increased the cell numbers of tumor-infiltrating CD8+ T cells and their expressions of CD107a and TNF-α. The cell numbers of tumor-infiltrating NK cells was not affected, but the expression of activation markers was significantly increased after treatment. Together, our results demonstrate that combination therapy effectively against advanced HCC through activating tumor-infiltrating NK cells and tumor-specific CD8+ T cells, enhancing Ag presentation ability of DCs while reducing the suppressive functions of MDSCs.

Combination therapy of radiation and interleukin 12 induced regression of large orthotopic liver cancers by modulation of tumor microenvironment (VAC12P.1111)

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide with few therapeutic options. Radiation is one of the mainstay cancer therapies. We hypothesize that combination of radiation and local interleukin 12 (IL-12) immunotherapy may change the suppressive tumor microenvironment to a proinflammatory condition favorable in induction of antitumor immune responses. IL-12 has potent antitumor activities through activation of CD8+ T cells and natural killer cells, reprogramming several types of myeloid-derived suppressor cells to a phenotype that favors immune activation, and inhibiting new blood vessel formation within tumors. Our data showed that combination of radiation and intratumoral injection of an adenoviral vector encoding IL-12 (Ad/IL-12) led to tumor regression in the majority of animals bearing large orthotopic hepatocellular carcinoma and significantly prolonged their survival. Single treatment of radiation or Ad/IL-12 delayed tumor growth but did not result in tumor regression. Mechanistic studies revealed that combination therapy greatly increased the cell numbers and activities of tumor-infiltrating CD8+ T cells, while the cell numbers and suppressive functions of MDSC and tumor-associated macrophages (TAM) were significantly decreased. Our results strongly suggest that a combinatorial treatment of radiation and IL-12 may represent an alternative therapy for advanced HCC.

Abstract 721: Suppression of orthotopic liver cancers by a combinatorial therapy of radiation and adenoviral vectors expressing interleukin 12

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. Because of difficulty in early diagnosis, only a minority of HCC patients are candidates for resection or transplantation, the traditional curative treatments. Recent development of image-guided radiotherapy and stereotactic radiotherapy offer an alternative therapeutic option for HCC patients with advanced diseases. In addition to eradicate tumor cells via DNA double-strand breaks or induction of apoptosis, radiotherapy also induces immunogenic tumor cell death, releasing a variety of danger-signaling molecules, which may help induce adaptive immune responses against the irradiated local tumors as well as the non-irradiated metastatic tumors. To further increase the therapeutic effect and enhance the antitumor immune responses, we proposed to combine radiation therapy with interleukin 12 (IL-12), a cytokine which has the ability to sensitize suppressive tumor-associated bone marrow-derived stromal cells, enhancing their ability to stimulate CD4+ and CD8+ T cell responses. BALB/c mice were injected at the left liver lobe of 3 x 105 BNL cells, a murine HCC cell line. At day 10, when the tumor volume reaching about 50 mm3, the hepatic tumors were receiving the following treatment: (1) a single dose of radiation of 10 Gy delivering at a mean dose rate of 6.72 Gy/min, (2) a single intratumoral injection of 108 p.f.u. of adenoviral vectors encoding a single-chain murine IL-12 (Ad/IL-12), (3) a combination therapy of 10 Gy radiation and 108 p.f.u. Ad/IL-12, and (4) no treatment. At day 30, mice were sacrificed and the tumor volume was measured by a caliper. The tumors in the control none treated group grew progressively with a mean tumor volume of 2,797 ± 304 mm3. The single treatment of radiation or Ad/IL-12 resulted in objective tumor growth suppression, reducing the mean tumor volume to 367 ± 203 mm3 and 241 ± 204 mm3, respectively, but none of the tumors were regressed after the single agent treatment. In contrast, the combinatorial treatment of radiation and Ad/IL-12 led to a partial (> 50% regression) or complete tumor regression in 80% (8 of 10) of tumors and substantially delayed tumor growth in the tumor-bearing mice. Our preliminary data also showed that the combinatorial treatment of radiation and Ad/IL-12 induced antitumor immune responses and suppressed systemic metastasis. Mechanistic studies of the combinatorial treatment of radiation and Ad/IL-12 are under investigation. Our results suggest that a combinatorial treatment of radiation and IL-12 may represent an alternative therapy for advanced HCC.

Citation Format: Mi-Hua Tao, Wen-Shan Tsao, Ping-Yi Wu. Suppression of orthotopic liver cancers by a combinatorial therapy of radiation and adenoviral vectors expressing interleukin 12. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 721. doi:10.1158/1538-7445.AM2014-721

Studies of efficacy and liver toxicity related to adeno-associated virus-mediated RNA interference

Adeno-associated virus (AAV)-mediated RNA interference shows promise as a therapy for chronic hepatitis B virus (HBV) infection, but its low efficacy and hepatotoxicity pose major challenges. We have generated AAV vectors containing different promoters and a panel of HBV-specific short hairpin RNAs (shRNAs) to investigate factors that contribute to the efficacy and pathogenesis of AAV-mediated RNA interference. HBV transgenic mice injected with high doses of AAV vectors containing the U6 promoter produced abundant shRNAs, transiently inhibited HBV, but induced severe hepatotoxicity. Sustained HBV suppression without liver toxicity can be achieved by lowering the dose of AAV-U6 vectors. AAVs containing the weaker H1 promoter did not cause liver injury, but their therapeutic efficacy was highly dependent on the sequence of the shRNA. Mice treated with the toxic U6-promoter-driven shRNA showed little change in hepatic microRNA levels, but a dramatic increase in hepatic leukocytes and inflammatory cytokines and chemokines. Hepatotoxicity was completely absent in immunodeficient mice and significantly alleviated in wild-type mice depleted of macrophages and granulocytes, suggesting that host inflammatory responses are the major cause of liver injury induced by the overexpressed shRNAs from AAV-U6 vectors. Our results demonstrate that selection of a highly potent shRNA and control its expression level is critical to achieve sustained HBV suppression without inducing inflammatory side effects.

A murine model of hepatitis B-associated hepatocellular carcinoma generated by adeno-associated virus-mediated gene delivery

A relevant animal model is critical for investigating the pathogenic mechanisms underlying hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC). Mice are not naturally infected by HBV, presumably due to the lack of HBV receptors on mouse hepatocytes. To bypass this entry step of HBV infection, we report generation of a novel HBV model in immunocompetent mice by hepatic delivery of the HBV genome using trans-splicing adeno-associated viral vectors (AAV/HBV). We confirmed production of HBV virions and proteins in the liver and circulation in all AAV/HBV-transduced mice in all four immunocompetent mouse strains tested. These mice produced antigen and antibody profiles similar to that observed in chronic HBV patients. Importantly, 12-16 months later, all 12 AAV/HBV-transduced mice developed macroscopically visible liver-tumor nodules. Ten of the twelve tumors were characterized with typical HCC features. This AAV/HBV-transduced murine HCC model provides a useful instrument for studying the pathogenesis of HBV-associated HCC and the development of HCC therapeutic interventions.

Differential antitumor effect of interleukin-12 family cytokines on orthotopic hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most difficult cancers to treat. The interleukin (IL)-12 family cytokines, including IL-12, IL-23 and IL-27, display overlapping, but not redundant, roles in regulating lymphocyte subpopulations. IL-12 is known as a potent antitumor cytokine, whereas the results of the antitumor effect of IL-23 and IL-27 are inconsistent. The present study aimed to directly compare the relative antitumor efficacy of these three IL-12 family cytokines on HCC.

METHODS

A murine orthotopic BNL HCC model, in which the tumor is located in an environment heavily populated with different lymphocyte subsets, was established. The hepatotropic adeno-associated virus serotype 8 (AAV8) vector was used to deliver the cytokine genes aiming to achieve sustained cytokine expression in the liver.

RESULTS

AAV8/IL-12 treatment significantly reduced hepatic metastases and prolonged survival time, whereas treatment with AAV8/IL-23 or AAV8/IL-27 had only moderate antitumor effects at a high dose. The antitumor efficacy of these cytokines was positively correlated with their ability to regulate hepatic T cells, natural killer cells and natural killer T cells, with IL-12 greatly increasing the number and activation status of these cells, whereas IL-27 had no effect and IL-23 had a negative effect. AAV8/IL-12 treatment also resulted in a marked decrease in tumor vessel density, which was not observed with AAV8/IL-23 and AAV8/IL-27 treatment.

CONCLUSIONS

The data obtained in the present study highlight the importance of local lymphocytes and anti-angiogenesis for influencing the antitumor activity of these three IL-12 family cytokines and suggest that IL-12 is the best candidate for treating HCC.

Treatment of hepatocellular carcinoma with adeno-associated virus encoding interleukin-15 superagonist

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, but effective therapies are still needed. The liver has been identified as an important immune organ and is heavily populated with various lymphocyte subsets known to play important roles in cancer immunosurveillance. We hypothesized that activation of hepatic lymphocytes by interleukin (IL)-15, a cytokine known for its ability to trigger proliferation and activation of natural killer (NK) cells, natural killer T cells, and memory CD8(+) T cells, might offer an alternative therapy for HCC. We employed hepatotropic adeno-associated virus serotype 8 (AAV8) to deliver an IL-15 superagonist (IL-15-IL-15RalphaS), consisting of IL-15 covalently linked to the N-terminal sushi domain of the IL-15 receptor alpha chain, to achieve local sustained cytokine expression in the liver environment. We observed that a single injection of AAV8 expressing IL-15-IL-15RalphaS, but not IL-15 alone, greatly expanded the number of hepatic mononuclear cells, mainly NK cells, for at least 21 days. AAV8/IL-15-IL-15RalphaS treatment generated potent antitumor activity in a liver metastatic murine HCC model (BNL cells), and significantly prolonged the survival time of treated animals. The antitumor effect depended mainly on NK cells, not on CD8(+) and CD4(+) T cells, because AAV8/IL-15-IL-15RalphaS treatment greatly enhanced the cytolytic activity of hepatic NK cells and depletion of NK cells abrogated the therapeutic effect. Importantly, no apparent liver toxicity was observed during AAV8/IL-15-IL-15RalphaS treatment. Together, our data demonstrate that AAV8-delivered IL-15-IL-15RalphaS provides an effective and safe therapy against metastatic HCC.

Development and validation of gene therapies in autoimmune diseases: Epidemiology to animal models

Recent advancement in immunology, molecular biology, and bioinformatics has yielded extensive information on the pathophysiological mechanisms of autoimmunity, which has greatly facilitated the identification of potential therapeutic targets and the development of gene therapy in the treatment of autoimmune disease. Preclinical studies were carried out in animal models. This phenomenon is well illustrated in two prototypic animal models of autoimmune disease: the autoimmune encephalomyelitis (EAE) model of multiple sclerosis (MS) and collagen-induced arthritis (CIA) model in rheumatoid arthritis (RA). Here we discuss the current data on the development and validation of gene therapy in autoimmunity in these two models. The success in preclinical animal model studies provides the proof-of-concept of gene therapy for potential future applications in the treatment of autoimmune diseases. Furthermore, the identification of risk factors from epidemiological studies reveals further potential therapeutic targets to be examined in animal models.

Gene therapy in autoimmune diseases: challenges and opportunities

Clinical treatment of autoimmune disorders presents a special challenge. For decades, most clinical regimens in autoimmunity has been largely symptomatic and non-disease specific. Although data from vigorous research has lead to accumulating knowledge on the pathogenic and immunological mechanisms of many autoimmune diseases, their direct clinical applications have been sparse. Advances in biotechnology have laid the groundwork for potent and specific molecular targeting therapies by gene therapy, and have just begun to be investigated in the treatment of autoimmune disorders. Such work has been largely based on the availability of well-established animal models of common autoimmune disorders, and the efficacy of strategic approaches initially investigated and validated in these models. Although these preclinical animal model studies have provided the proof-of-concept for multiple potential applications, human clinical trials on gene therapy in autoimmunity are still at its infancy. The recent success of Phase I/II clinical trials of gene therapy in rheumatoid arthritis and multiple sclerosis, development of cutting edge technology in target identification, as well as gene delivery systems have now set the stage for a more thorough and vigorous pace in the near future to advance this exciting field.

Improved immunogenicity of a self tumor antigen by covalent linkage to CD40 ligand

The interaction between the CD40 ligand (CD40L) and CD40 on antigen-presenting cells (APCs) is critical in promoting humoral and cellular immune responses. Agonistic anti-CD40 monoclonal antibody and soluble CD40L can act as powerful adjuvants to promote vaccination, but usually require repeated high-dose treatment. In this study, we demonstrate that the adjuvant effect of CD40L can be greatly improved by directly linking the antigen to CD40L. We constructed a fusion protein (Id-CD40L) consisting of the extracellular domain of CD40L and the idiotype (Id) protein, a weakly immunogenic tumor-specific antigen derived from the murine 38C13 B-cell lymphoma. The soluble Id-CD40L fusion protein retained CD40 binding activity and stimulated CD80 and CD86 upregulation and interleukin (IL)-12 production by macrophages. Immunization of mice with Id-CD40L without adjuvants resulted in high titers of anti-Id Abs dominated by the IgG1 isotype and protected the mice from subsequent lethal tumor challenge. In a dose-response study, we demonstrated that Id-CD40L elicited anti-Id antibody (Ab) responses in all immunized animals, even at a dose as low as 0.5 microg. Immunization with free Id and an IgG-CD40L fusion protein, which was identical in structure to Id-CD40L but lost the Id determinant, resulted in significant lower anti-Id responses, indicating that physical linkage between the tumor antigen and CD40L was required for the optimal immune response. These results demonstrate that fusing CD40L to a candidate antigen can greatly improve the adjuvant activity of CD40L. This approach may be useful in developing vaccines for a variety of malignant and infectious diseases.

Growth of preterm infants fed nutrient-enriched or term formula after hospital discharge

OBJECTIVE

At hospital discharge, preterm infants may have low body stores of nutrients, deficient bone mineralization, and an accumulated energy deficit. This double-blind, randomized study evaluated the growth of premature infants with birth weights <1800 g who were fed a 22 kcal/fl oz nutrient-enriched postdischarge formula (PDF) or a 20 kcal/fl oz term-infant formula (TF) from hospital discharge to 12 months' corrected age (CA).

METHODS

Infants were randomized to PDF or TF a few days before hospital discharge with stratification by gender and birth weight (<1250 g or >/=1250 g). The formulas were fed to 12 months' CA. Growth was evaluated using analysis of variance controlling for site, feeding, gender, and birth weight group. Interaction effects were also assessed. Secondary analyses included a repeated measures analysis and growth modeling.

RESULTS

One hundred twenty-five infants were randomized; 74 completed to 6 months' CA and 53 to 12 months' CA. PDF-fed infants weighed more than TF-fed infants at 1 and 2 months' CA, gained more weight from study day 1 to 1 and 2 months' CA, and were longer at 3 months' CA. There were significant interactions between feeding and birth weight group-among infants with birth weights <1250 g, those fed PDF weighed more at 6 months' CA, were longer at 6 months' CA, had larger head circumferences at term 1, 3, 6, and 12 months' CA, and gained more in head circumference from study day 1 to term and to 1 month CA. The repeated measures and growth modeling analyses confirmed the analysis of variance results. The PDF formula seemed to be of particular benefit for the growth of male infants. Infants fed the PDF consumed less formula and had higher protein intakes at several time points. Energy intakes, however, were not different.

CONCLUSIONS

Growth was improved in preterm infants fed a nutrient-enriched postdischarge formula after hospital discharge to 12 months' CA. Beneficial effects were most evident among infants with birth weights <1250 g, particularly for head circumference measurements.

Enhanced antitumor immunity by fusion of CTLA-4 to a self tumor antigen

The idiotypic determinant (Id) of the immunoglobulin expressed by a B-cell malignancy can serve as an effective tumor-specific antigen but is only weakly immunogenic. This study demonstrates that the immunogenicity of the tumor Id protein can be dramatically increased by directing it to antigen-presenting cells (APCs). Cytotoxic T-lymphocyte antigen 4 (CTLA-4) present on activated T cells has a strong binding affinity to both B7-1 and B7-2 molecules, which are primarily expressed on APCs. After construction of a fusion protein consisting of Id and CTLA-4 (Id-CTLA4), mice immunized with the fusion protein induced high titers of Id-specific antibody and T-cell proliferative responses without adjuvants and were protected from lethal tumor challenge. The Id-CTLA4 fusion protein was so potent that even low doses (down to 0.1 microg) of the immunogen were able to elicit strong antibody responses. By using an Id-CTLA4 mutant protein, the ability to bind B7 molecules on APCs was shown to be required for the enhanced immunogenicity of Id-CTLA4. These findings demonstrate that fusing CTLA-4 to a potential tumor antigen represents an effective approach to prime antitumor immunities in vivo and may be applicable to the design of vaccines for a variety of other diseases. (Blood. 2000;96:3663-3670)

Accelerated clearance of polyethylene glycol-modified proteins by anti-polyethylene glycol IgM

Tumor therapy by the preferential activation of a prodrug at tumor cells targeted with an antibody-enzyme conjugate may allow improved treatment efficacy with reduced side effects. We examined antibody-mediated clearance of poly(ethylene glycol)-modified beta-glucuronidase (betaG-sPEG) as a method to reduce serum concentrations of enzyme and minimize systemic prodrug activation. Enzyme-linked immunosorbent assay and immunoblot analysis of two monoclonal antibodies generated by immunization of BALB/c mice with an antibody-betaG-sPEG conjugate showed that mAb 1E8 (IgG1) bound betaG and betaG-sPEG whereas mAb AGP3 (IgM) bound poly(ethylene glycol). Neither antibody affected the betaG activity. mAb 1E8 and AGP3 were modified with 36 and 208 galactose residues (1E8-36G and AGP3-208G) with retention of 72 and 48% antigen-binding activity, respectively, to target immune complexes to the asialoglycoprotein receptor on liver cells. mAb 1E8 and AGP3 cleared betaG-PEG from the circulation of mice as effectively as 1E8-36G and AGP3-208G, respectively. mAb AGP3, however, cleared betaG-sPEG more completely and rapidly than 1E8, reducing the serum concentration of betaG-sPEG by 38-fold in 8 h. AGP3 also reduced the concentration of an antibody-betaG-sPEG conjugate in blood by 280-fold in 2 h and 940-fold in 24 h. AGP3-mediated clearance did not produce obvious damage to liver, spleen, or kidney tissues. In addition, AGP3 clearance of betaG-sPEG before administration of BHAMG, a glucuronide prodrug of p-hydroxyaniline mustard, prevented toxicity associated with systemic activation of the prodrug based on mouse weight and blood cell numbers. AGP3 should be generally useful for accelerating the clearance of PEG-modified proteins as well as for improving the tumor/blood ratios of antibody-betaG-PEG conjugates for glucuronide prodrug therapy of cancer.

Glutamine supplementation for low-birth-weight and very low-birth-weight infants

Glutamine is a conditionally essential amino acid for low-birth-weight (LBW) and very low-birth-weight (VLBW) infants by virtue of its ability to serve as a primary respiratory fuel for proliferating cells, a carrier of nitrogen between tissues, maintain acid-base balance, promote the growth and integrity of the gastrointestinal tract and promote immunologic responses. While adults can synthesize glutamine in the muscles and brain to meet essential requirements under normal state of health, the LBW and VLBW infants may not be able to do so since the enzymes (glutamine synthetase and glutaminase) activities are low. In addition, these infants are under stress due to conditions like the respiratory distress syndrome, acid-base imbalances, infections, and inadequate immunologic responses. Current amino acid mixtures and formula preparations are inadequate to meet the needs of these infants for this amino acid. Thus supplementation of parenteral and enteral nutrition with glutamine would be beneficial.

The management of patients with advanced motor neuron disease

BACKGROUND

There is no specific treatment for motor neuron disease (MND) except hospice or palliative care to improve patients' quality of life and decrease complications. This topic is seldom discussed in Taiwan.

METHODS

A retrospective study was conducted of patients with terminal MND who were treated and died at the Veterans General Hospital-Taipei from March 1986 through April 1996. Patients' characteristics, management, length of survival and cause of death were analyzed.

RESULTS

Twenty-three patients (M/F, 17/6) were included. The median age of onset was 59 years (range, 24-69). The median interval from onset of symptoms to diagnosis was nine months (range, 2-36). Seventeen patients received mechanical ventilation for an average median of six months. Nineteen patients had dysphagia, 17 received long-term nasogastric tube feeding, one had gastrostomy and one was treated with cricopharyngeal myotomy. Pain over the neck, trunk or limbs was reported by 18 patients; none received narcotics. Only two patients received respiratory exercise training and two had a cervical collar for stabilization. Electronic communication aids were not available. The median survival from onset of symptoms was 36 months (range, 7-99). The causes of death included sepsis (n = 13), respiratory failure (n = 7), heart disease (n = 2) and MND-related cachexia (n = 1). Cardiopulmonary resuscitation was performed for 12 patients.

CONCLUSIONS

In Taiwan, management of patients with advanced MND is mainly hospital-based and most of the effort is focused on life-sustaining. More attention needs to be paid to improvement of the quality of life and dignity of the patient.

Poly(ethylene glycol) modification of beta-glucuronidase-antibody conjugates for solid-tumor therapy by targeted activation of glucuronide prodrugs

Methoxypoly(ethylene glycol) (PEG) modification of Escherichia coli beta-glucuronidase (betaG) was examined as a method to improve the stability and pharmacokinetics of antibody-betaG conjugates for the targeted activation of glucuronide prodrugs at tumor cells. Introduction of 3 PEG molecules did not affect betaG activity whereas higher degrees of PEG modification produced progressively greater loss of enzymatic activity. The enzyme was found to be stable in serum regardless of PEG modification. PEG-modified betaG was coupled via a thioether bond to mAb RH1, an IgG2a antibody that binds to the surface of AS-30D hepatoma cells, to produce conjugates with 3 (RH1-betaG-3PEG), 5.2 (RH1-betaG-5PEG) or 9.8 (RH1-betaG-10PEG) PEG molecules per betaG with retention of 75%, 45% and 40% of the combined antigen-binding and enzymatic activity of the unmodified conjugate RH1-betaG. In contrast to the rapid serum clearance of RH1-betaG observed in mice, the PEG-modified conjugates displayed extended serum half-lives. RH1-betaG-3PEG and RH1-betaG-5PEG also exhibited reduced spleen uptake and greater tumor accumulation than RH1-betaG. BHAMG, the glucuronide prodrug of p-hydroxyaniline mustard (pHAM), was relatively nontoxic in vivo. Injection of 6 mg/kg or 12 mg/kg pHAM i.v. depressed white blood cell numbers by 46% and 71% whereas 80 mg/kg BHAMG reduced these levels by 22%. Although the tumor/blood ratio of RH1-betaG-5PEG was adversely affected by slow clearance from serum, combined therapy of small solid hepatoma tumors with this conjugate, followed 4 and 5 days later with i.v. injections of BHAMG, cured all of seven mice with severe combined immunodeficiency. Combined treatment with a control antibody-betaG conjugate and BHAMG delayed tumor growth and cured two of six mice while treatment with pHAM or BHAMG alone was ineffective.

Infant of diabetic mother: a continuing challenge for perinatal-neonatal medicine

Current increase in the incidence of diabetes mellitus complicating pregnancy is of concern since it is associated with an increase in mortality and morbidity of the fetus and neonate. Pregnancy itself is diabetogenic caused by increased insulin resistance due to the production of hormones like estrogen, progesterone, cortisol, human chorionic somatomammotropin (hCS) and human placental lactogen (hPL). The latter increases lypolysis which provides free fatty acids and ketones as fuels for energy for the pregnant mother. This spares maternal blood glucose, amino acids and ketones which cross the placenta to the fetus. The influx of nutrients increases fetal insulin production which together with hPL induce somatogenesis. Maternal hyperglycemia and fetal hypoxemia are shown to be responsible for structural congenital anomalies of the rapidly developing organs of the fetus during the early weeks of gestation while continuing hyperglycemia and hypoxemia in the second and third trimester are factors related to the production of macrosomia, including cardiomyopathy, delay in lung maturation, and polycythemia. Metabolic problems such as hypoglycemia, hypocalcemia, hypomagnesemia and hyperbilirubinemia are common neonatal morbidities. Follow-up of the infants of diabetic mothers indicates that these infants have a 20 fold increase in acquiring diabetes. Early identification of maternal diabetes with strict metabolic control prior to conception as well as throughout pregnancy together with careful fetal monitoring can reduce the incidence of congenital anomalies and morbidities in the fetus and neonate.

Effects of the callipyge phenotype on serum creatinine, total cholesterol, low-density lipoproteins, very-low-density lipoproteins, high-density lipoproteins, and triacylglycerol in growing lambs

The goals of this study were to investigate the effects of the callipyge (CLPG) phenotype on serum creatinine and lipid profiles of growing lambs. Preliminary studies in our laboratories indicated that creatinine may have utility in distinguishing the CLPG phenotype and that expression of the CLPG gene altered concentrations of serum total cholesterol (TC). As a result, in this study, we examined the influence of the CLPG gene on concentrations of creatinine, TC, very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL), high-density lipoproteins (HDL), and triacylglycerol (TG) at varying stages of maturity in lambs. Ten homozygous (c/c) Polypay ewes were crossed with Dorset rams heterozygous for the CLPG gene (C/c). From this cross, 20 lambs (13 females and 7 males) were born, of which 11 were homozygotic (c/c) and 9 were heterozygotic (C/c; CLPG) based on muscle weights and longissimus dorsi (LD) area at slaughter. Blood samples were taken at monthly intervals and serum lipid constituents were assayed. At 1 mo of age, no differences (P > .05) in plasma lipids were detectable between phenotypes. However, at 2 mo age, CLPG lambs had higher (P < .01) concentration of TG, TC, HDL, and VLDL compared to homozygotic (c/c) lambs. Triglycerides and VLDL were elevated (P < .05) in CLPG lambs at 3 mo of age. By slaughter, no differences (P > .05) in serum lipid constituents were detectable between genotypes. Hence, the increase in serum TC is due to elevated levels of HDL and VLDL. These observations indicate that creatinine may be used to distinguish CLPG lambs and that the CLPG gene alters serum lipid profiles during the postnatal period.

[Ultrasonography of hips in neonates]

For evaluation of the development of the hip joints in young infants, between Jun., 1988 and Oct., 1991, 522 hips of the infants under 4 months of age were studied by ultrasonography based on the method well described by Graf. The results revealed only 48% of the hips of neonatal group was type I (stable type). But this percentage increased with age: 90% in the group under 2 months of age; 97% in the group under 4 months of age. Compared with the findings of other studies in Europe, the development and the stability of the hips of our neonatal group seemed poorer. But this condition improved much within 2 months after birth. So we concluded that, except the high risk group, the ultrasonographic screening approach should be performed after 2 months of age, but not in neonatal period under considering the cost-benefit.

Use of fetal ultrasound to select metabolic therapy for pregnancies complicated by mild gestational diabetes

OBJECTIVE

To determine whether fetal ultrasound early in the third trimester can identify Latina with mild gestational diabetes mellitus (GDM) whose fetuses are at risk for macrosomia and, if so, whether maternal insulin therapy can reduce that risk.

RESEARCH DESIGN AND METHODS

Study subjects included 303 consecutive women with GDM and a fasting serum glucose level < 5.8 mM on diet therapy who had a fetal ultrasound between 29 and 33 weeks gestation. Of the women, 98 (32%) had a fetal AC > or = 75th percentile for gestational age, and 59 women completed a randomized trial of diet therapy (n = 29) or diet plus twice daily insulin (n = 30). Maternal nutrient levels were assessed by meal tolerance testing (MTT) before and during therapy and by capillary glucose monitoring four to seven times a day. Birth weights corrected for gestational age and neonatal glycemia and skin folds were the primary outcome variables compared between treatment groups.

RESULTS

Diet and diet-plus-insulin groups were well matched for maternal age, prepregnancy relative weight, weight gain during pregnancy, and glycemia at entry. Insulin therapy reduced maternal capillary (P < 0.005) and MTT (P < 0.001) glucose levels and prevented a diet-associated rise in MTT triglyceride levels (P < 0.002). Gestational age at delivery was similar in insulin- and diet-treated groups (39.6 +/- 0.2 vs. 39.5 +/- 0.2 weeks). Birth weights (3,647 +/- 67 vs. 3,878 +/- 84 g; P < 0.02), the prevalence of large-for-gestational age infants (13 vs. 45%, P < 0.02), and neonatal skin-fold measurements at three sites (P < 0.005) were reduced in the insulin-treated group. Rates of transient neonatal hypoglycemia were low in both treatment groups (14 and 18%, respectively) and did not differ significantly between groups.

CONCLUSIONS

Fetal ultrasound early in the third trimester identified women with mild GDM whose infants were at high risk for fetal macrosomia in the absence of standard glycemic criteria for insulin therapy. Insulin treatment reduced the macrosomia, indicating that fetal ultrasound can be used to guide metabolic therapy in pregnancies complicated by mild GDM.

Testing for drugs of abuse in meconium of newborn infants

A reliable and sensitive screening procedure has been developed for drugs of abuse (amphetamines, cocaine metabolites, opiates, and phencyclidine [PCP]) in meconium from infants. The substances in meconium were extracted with chloroform-isopropanol (3:1) and screened by enzyme multiplied immunoassay technique (EMIT). The lower detection limits of the EMIT for benzoylecgonine, d-methamphetamine, morphine, and PCP were 250 ng/g, 730 ng/g, 110 ng/g, and 100 ng/g, respectively. This method was applied to meconium from 50 infants born to mothers suspected of using the drugs of abuse during pregnancy. Of the 50, 12 were positive for benzoylecgonine, seven for opiates, and one for PCP. The presence of benzoylecgonine and PCP in meconium was confirmed by gas chromatography/mass spectrometry and that of opiates by thin-layer chromatography. The routine analysis of meconium for drugs of abuse is recommended in cases where (A) urine can not be obtained or (B) urinalysis is negative for the substances despite a strong suspicion of maternal use of the substances during pregnancy.

Gastrointestinal tolerance, fat absorption, plasma ketone and urinary dicarboxylic acid levels in low-birth-weight infants fed different amounts of medium-chain triglycerides in formula

This study was conducted to evaluate the effect of medium-chain triglycerides (MCT) in a formula for low-birth-weight (LBW) infants on gastrointestinal tolerance, fat absorption, plasma ketone levels, and urinary dicarboxylic acid (DCA) excretion. At the start of enteral feedings, 64 LBW infants (< or = 1500 g) were randomly assigned to one of four experimental formulas. The formulas contained either 0, 17, 34, or 50% of the total fat as MCT oil. The nonfat constituents of all four formulas were the same and identical to Similac Special Care 24 (SCF). Infants were studied from the start of enteral feeding until approximately 7 days after reaching full feeds. Growth and tolerance were assessed in all infants over the entire feeding period. A 48-h balance study was conducted after enteral intake exceeded 100 kcal/kg/day for 3 days. Stool fat, plasma D-(-)-3-hydroxybutyrate (3HB) and carnitine, serum glucose, and urinary DCA levels were determined. Groups did not differ in growth, formula intake, fat absorption (76-84%), serum glucose, or plasma carnitine levels. Gastrointestinal tolerance was excellent and did not differ among groups. Plasma 3HB was significantly different (p < 0.05) only between the 0 and 50% MCT groups, 50 +/- 10 versus 120 +/- 20 microM, respectively. The excretion of urinary DCAs increased with increasing amounts of MCT in the formula. In conclusion, fat absorption and gastrointestinal tolerance were not affected by different MCT levels (0 to 50% of the total fat), but higher levels of plasma 3HB and urinary DCAs were associated with higher levels of MCT in the LBW formulas studied.

A comparison of rat brain amino acid and monoamine content in diazepam withdrawal and after exposure to a phobic stimulus

1. The content of amino acids (taurine, glycine, glutamic acid, gamma-aminobutyric acid (GABA) and aspartic acid) and monoamines (5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and noradrenaline) in homogenates of rat cortical and hippocampal tissue were measured by high performance liquid chromatography (h.p.l.c.) with fluorescent and electrochemical detection respectively, after two anxiogenic treatments: exposure to a phobic stimulus (cat odour) and withdrawal from chronic diazepam treatment. 2. In neither of the two anxiogenic situations was there a significant change in any amino acid content, in either brain area. 3. In the group withdrawn from chronic diazepam, cortical 5-HT and 5-HIAA levels and hippocampal 5-HT levels were significantly increased. Noradrenaline content was significantly decreased in the hippocampus. 4. The changes in 5-HT and 5-HIAA levels following cat odour exposure were area-specific in that they decreased in the hippocampus, but increased in the cortex. 5. Following cat odour exposure, noradrenaline levels appeared not to change in either area studied. However during exposure to cat odour, it was found that half the animals avoided the odour source and half were indifferent. The animals showing marked avoidance had significantly higher cortical noradrenaline content and this was significantly different from control, whereas hippocampal noradrenaline levels were not dependent upon the differences in avoidance of the odour source. 6. The results show clearly different neurochemical changes in the rat following exposure to a phobic stimulus and withdrawal from diazepam. It is hoped comparative studies such as this will enable better understanding of anxiety states in the rat which could parallel the different classes of anxiety recognised in the clinic

Benzodiazepines increase preprocholecystokinin messenger RNA levels in rat brain

Using in situ hybridisation, the effects of acute and chronic diazepam administration and diazepam withdrawal on preprocholecystokinin (CCK) mRNA levels in discrete regions of rat brain were determined. In cerebral cortex and a subpopulation of hippocampal neurones, CCK mRNA levels were increased after a single injection of diazepam and 24 h after withdrawal from chronic diazepam treatment, but not after chronic diazepam treatment. These results show that, in some neuronal groups, CCK mRNA expression is regulated by benzodiazepines, although there is no clear link between CCK mRNA levels and anxiety state.

Transient and sustained components of the pupillary responses evoked by luminance and color

That the pupil reacts to changes in luminance and color, as well as to spatial features in the retinal image raises questions about whether phasic and tonic and/or color and luminance visual pathways project to the pretectal pupillomotor neurons. The present study compares pupillary responses evoked by heterochromatic and achromatic luminance increments to investigate whether the pupillary responses evoked by color and by luminance are independent of one another. Principal component analysis is used to examine the constituents of the pupil responses. The results support the belief that the visual input to the pupillomotor system is organized into phasic and tonic (but not necessarily independent color and luminance) pathways.

An object-based approach to medical process automation

The medical events of providers rendering services for patient care are necessarily interrelated. A clinical information system must reliably record these events and relate the information about their inter-dependency. The quality of clinical information therefore depends crucially on the proper coordination and tracking of these events according to established protocols. We introduce an object-based approach to define medical processes for their automation. For each medical process, we capture in one logical unit, an event-driven mechanism to coordinate of inter-dependent medical events of the process, and the data relevant to the process. We call the encapsulated unit a form object. Moreover, the form object may contain sub-objects each of which also encapsulates its own protocol knowledge and relevant information. In contrast to other approaches, the form object facilitates for administering medical processes due to its locality of definition, and its event-driven paradigm reflects medical events more naturally.

The role of 5-HT in the anxiogenic effects of acute ethanol withdrawal and in the long-lasting cognitive deficits

There was a significant increase in potassium-stimulated release of 3H-[5-HT] from hippocampal slices taken from rats withdrawn from chronic ethanol treatment, compared with control-treated rats. The anxiogenic behaviour observed 12 h after ethanol withdrawal was inhibited by the 5-HT1A partial agonist, buspirone (200 micrograms/kg s.c.), indicating that the increased 5-HT release might underlie the anxiogenic response. The ex-ethanol treated rats showed impaired habituation of motor activity in the holeboard and a reduced exploratory response. The latter, but not the former, were reversed by the 5-HT3 receptor antagonist, ondansetron (0.01 microgram/kg i.p.). Ondansetron was without effect on working memory errors, but significantly increased the number of reference memory errors made by the ex-ethanol group. It also had a significantly anxiogenic effect in this group. These results suggest that the chronic ethanol treatment changes the 5-HT system and has long-lasting effects on the function of 5-HT3 receptors.

Modification of chlordiazepoxide's behavioural and neurochemical effects by handling and plus-maze experience

The purpose of the present experiment was to determine how a rat's prior history (of repeated gentle handling and/or of the elevated plus-maze apparatus) modified the behavioural and neurochemical response to chlordiazepoxide. In handled animals one previous exposure to the plus-maze rendered the rats insensitive to the anxiolytic effects of chlordiazepoxide in this test. This phenomenon of 'one-trial tolerance' was not seen in unhandled rats and thus both prior handling and prior maze experience were necessary to abolish the behavioural response to chlordiazepoxide. The effects of chlordiazepoxide on K(+)-evoked [14C]GABA (gamma-aminobutyric acid) release were also modified by the rat's past history. The drug-induced reduction of GABA release in the cortex was abolished by prior plus-maze experience; whereas handling modified chlordiazepoxide's effects on GABA release in the hippocampus (the drug decreased release in unhandled rats and increased release in those given repeated gentle handling). Thus an anxiolytic response to chlordiazepoxide in the plus-maze was accompanied by reduced GABA release in both cortex and hippocampus. The 5-HT system (5-hydroxytryptamine) also proved sensitive to the rats' past history. The effects of chlordiazepoxide on K(+)-evoked [3H]5-HT release from the hippocampus depended on both prior handling and plus-maze experience and could be predicted from the undrugged level of evoked release; when this was low, chlordiazepoxide increased it, when it was high, chlordiazepoxide reduced it. These results raise the possibility that the beneficial effects of a benzodiazepine may depend on the baseline condition of the animals.

[The interrelationship between the O2-dependent bactericidal mechanism and hyperbilirubinemia of newborn]

In order to investigate the influence of indirect bilirubin to O2-dependent bactericidal mechanism in adult and newborn phagocytes we use the NBT reduction activity of granulocytes and monocytes as index, by infiltrated granulocytes and monocytes in different concentration of indirect bilirubin with or without latex stimulator. The NBT reduction activity of granulocytes infiltrated in 20 mg/dl indirect bilirubin will increase slightly, compared to uninfiltrated; but with latex stimulator, the increment will decrease significantly, this change is reversible, when indirect bilirubin be washed, the stimulating capacity by latex stimulator in granulocyte will be stronger; there were no such change pattern in monocytes. Since there were a big difference in NBT reduction activity of granulocytes and monocytes between newborns, with or without latex stimulator, we can't get a satisfied result. Indirect bilirubin in cells will increase NBT reduction activity of monocytes, but not in granulocytes.