Mark O. Lively

Pepsin and Carbonic Anhydrase Isoenzyme III as Diagnostic Markers for Laryngopharyngeal Reflux Disease

Objectives/Hypothesis: The objective was to investigate the potential use of pepsin and carbonic anhydrase isoenzyme III (CA‐III) as diagnostic markers for laryngopharyngeal reflux disease.

Activity/stability of human pepsin: Implications for reflux attributed laryngeal disease

Objectives/Hypothesis: Exposure of laryngeal epithelia to pepsin during extra‐esophageal reflux causes depletion of laryngeal protective proteins, carbonic anhydrase isoenzyme III (CAIII), and squamous epithelial stress protein Sep70. The first objective of this study was to determine whether pepsin has to be enzymatically active to deplete these proteins. The second objective was to investigate the effect of pH on the activity and stability of human pepsin 3b under conditions that might be found in the human esophagus and larynx.

Flagellin-F1-V Fusion Protein Is an Effective Plague Vaccine in Mice and Two Species of Nonhuman Primates

ABSTRACT A number of studies have clearly demonstrated that flagellin is a potent adjuvant that promotes robust immune responses when it is given with a protein antigen. In view of the potential biological and practical benefits of a recombinant protein vaccine composed of a single fusion protein containing flagellin and antigen, we have evaluated the efficacy of a fusion protein composed of flagellin and two protective antigens of Yersinia pestis (F1 and V) in eliciting protection against respiratory challenge with Y. pestis. Flagellin-F1-V was produced and purified in high yield under good manufacturing practices conditions. The fusion protein retains full Toll-like receptor 5-stimulating activity in vitro. Using a prime-boost immunization protocol, we found that flagellin-F1-V elicits robust antigen-specific humoral immunity in mice and two species of nonhuman primates. Immune mice were fully protected against intranasal challenge with 150 mean tolerated doses of Y. pestis CO92. In immune mice, the bacteria were completely cleared within 3 days after challenge. Flagellin-F1-V exhibited full stability for at least 297 days at 4°C and at least 168 days at 25°C. At between 29 and 84 days at 37°C, the protein exhibited a loss of biological activity that appeared to be associated with a substantial change in protein diameter, possibly due to oligomerization. On the basis of our results, we believe that flagellin-F1-V is an outstanding candidate for evaluation in studies with humans.

Activation and Deactivation of DNAzyme and Antisense Function with Light for the Photochemical Regulation of Gene Expression in Mammalian Cells

The photochemical regulation of biological systems represents a very precise means of achieving high-resolution control over gene expression in both a spatial and a temporal fashion. DNAzymes are enzymatically active deoxyoligonucleotides that enable the site-specific cleavage of RNA and have been used in a variety of in vitro applications. We have previously reported the photochemical activation of DNAzymes and antisense agents through the preparation of a caged DNA phosphoramidite and its site-specific incorporation into oligonucleotides. The presence of the caging group disrupts either DNA:RNA hybridization or catalytic activity until removed via a brief irradiation with UV light. Here, we are expanding this concept by investigating the photochemical deactivation of DNAzymes and antisense agents. Moreover, we report the application of light-activated and light-deactivated antisense agents to the regulation of gene function in mammalian cells. This represents the first example of gene silencing antisense agents that can be turned on and turned off in mammalian tissue culture.

Sensitive Pepsin Immunoassay for Detection of Laryngopharyngeal Reflux

Objectives/Hypothesis: To determine whether measurement of pepsin in throat sputum by immunoassay could be used as a sensitive and reliable method for detecting laryngopharyngeal reflux (LPR) compared with 24‐hour double‐probe (esophageal and pharyngeal) pH monitoring.

C60-Fullerenes: detection of intracellular photoluminescence and lack of cytotoxic effects

We have developed a new method of application of C60 to cultured cells that does not require water-solubilization techniques. Normal and malignant cells take-up C60 and the inherent photoluminescence of C60 is detected within multiple cell lines. Treatment of cells with up to 200 μg/ml (200 ppm) of C60 does not alter morphology, cytoskeletal organization, cell cycle dynamics nor does it inhibit cell proliferation. Our work shows that pristine C60 is non-toxic to the cells, and suggests that fullerene-based nanocarriers may be used for biomedical applications.

Effect of pepsin on laryngeal stress protein (Sep70, Sep53, and Hsp70) response: Role in laryngopharyngeal reflux disease

Objectives: The objectives of this study were to define the conditions that give rise to a stress protein response in laryngeal epithelium and to investigate whether and how stress protein dysfunction contributes to reflux-related laryngeal disease. Methods: Western analysis was used to measure stress protein (squamous epithelial proteins Sep70 and Sep53 and heat shock protein Hsp70) and pepsin levels in esophageal and laryngeal tissue specimens taken from both normal control subjects and patients with pH-documented laryngopharyngeal reflux (LPR) who had documented lesions, some of whom had laryngeal cancer. A porcine organ culture model was used to examine the effects of low pH and pepsin (0.1% porcine pepsin A) on stress protein levels. A laryngeal squamous carcinoma (FaDu) cell line was used to examine uptake of human pepsin 3b-tetramethyl-5 and -6 isothiocyanate. Results: Sep70, Sep53, and Hsp70 were found to be expressed at high levels, and pepsin was not detected, in esophageal and laryngeal specimens taken from normal control subjects and in esophageal specimens taken from LPR patients. The patients with LPR were found to have significantly less laryngeal Sep70 (p = .027) and marginally less laryngeal Sep53 (p = .056) than the normal control subjects. Laryngeal Hsp70 was expressed at high levels in the LPR patients. The patients with laryngeal cancer had significantly lower levels of Sep70, Sep53 (p < .01), and Hsp70 (p < .05) than the normal control subjects. A significant association was found between the presence of pepsin in laryngeal epithelium from LPR patients and depletion of laryngeal Sep70 (p < .001). Using the organ culture model, we demonstrated that laryngeal Sep70 and Sep53 proteins are induced after exposure to low pH. However, in the presence of pepsin, Sep70 and Sep53 levels are depleted. Confocal microscopy analysis of cultured cells exposed to labeled pepsin revealed that uptake is by receptor-mediated endocytosis. Conclusions: These findings suggest that receptor-mediated uptake of pepsin by laryngeal epithelial cells, as may occur in LPR, causes a change in the normal acid-mediated stress protein response. This altered stress protein response may lead to cellular injury and thus play a role in the development of disease.

Gene Silencing in Mammalian Cells with Light-Activated Antisense Agents

Detailed knowledge of the external regulation of gene func-tion is a fundamental necessity in order to annotate sequencedgenomes and to understand biological processes in single cellsand multicellular organisms. One of the most widely used ap-proaches for the down-regulation of specific genes is the ap-plication of antisense agents. Antisense agents are oligomersthat have the ability to hybridize sequence specificslly tomRNAs, inhibiting translation and potentially leading to mRNAdegradation through RNAse H recruitment.

Conserved and Variant Molecular and Functional Features of Multiple Egg Yolk Precursor Proteins (Vitellogenins) in White Perch (Morone americana) and other Teleosts

Three complete cDNAs encoding different forms of vitellogenin (Vtg) were isolated from a white perch (Morone americana) liver cDNA library and characterized with respect to immunobiochemical and functional features of the three Vtgs and their product yolk proteins (YPs) in this species and in the congeneric striped bass (Morone saxatilis). The two longest cDNAs encoded Vtgs with a complete suite of yolk protein domains that, based on comparisons with vtg sequences from other species, were categorized as VtgAa and VtgAb using the current nomenclature for multiple teleost Vtgs. The shorter cDNA encoded a Vtg that lacked a phosvitin domain, had a shortened C-terminus, and was categorized as VtgC. Mapping of peptide sequences from the purified Vtgs and their derived YPs to Vtg sequences deduced from the cDNAs definitively identified the white perch VtgAa, VtgAb, and VtgC proteins. Detailed comparisons of the primary structures of each Vtg with partial or complete sequences of Morone yolk proteins or of Vtgs from other fishes revealed conserved and variant structural elements of teleost Vtgs with functional significance, including, as examples, signal peptide cleavage sites, dimerization sites, cathepsin D protease recognition sites, and receptor-binding domains. These comparisons also yielded an interim revision of the classification scheme for multiple teleost Vtgs.

Induction of Robust Type-I CD8+ T-cell Responses in WHO Grade 2 Low-Grade Glioma Patients Receiving Peptide-Based Vaccines in Combination with Poly-ICLC

Purpose: WHO grade 2 low-grade gliomas (LGG) with high risk factors for recurrence are mostly lethal despite current treatments. We conducted a phase I study to evaluate the safety and immunogenicity of subcutaneous vaccinations with synthetic peptides for glioma-associated antigen (GAA) epitopes in HLA-A2+ adults with high-risk LGGs in the following three cohorts: (i) patients without prior progression, chemotherapy, or radiotherapy (RT); (ii) patients without prior progression or chemotherapy but with prior RT; and (iii) recurrent patients. Experimental Design: GAAs were IL13Rα2, EphA2, WT1, and Survivin. Synthetic peptides were emulsified in Montanide-ISA-51 and given every 3 weeks for eight courses with intramuscular injections of poly-ICLC, followed by q12 week booster vaccines. Results: Cohorts 1, 2, and 3 enrolled 12, 1, and 10 patients, respectively. No regimen-limiting toxicity was encountered except for one case with grade 3 fever, fatigue, and mood disturbance (cohort 1). ELISPOT assays demonstrated robust IFNγ responses against at least three of the four GAA epitopes in 10 and 4 cases of cohorts 1 and 3, respectively. Cohort 1 patients demonstrated significantly higher IFNγ responses than cohort 3 patients. Median progression-free survival (PFS) periods since the first vaccine are 17 months in cohort 1 (range, 10–47+) and 12 months in cohort 3 (range, 3–41+). The only patient with large astrocytoma in cohort 2 has been progression-free for more than 67 months since diagnosis. Conclusion: The current regimen is well tolerated and induces robust GAA-specific responses in WHO grade 2 glioma patients. These results warrant further evaluations of this approach. Clin Cancer Res; 21(2); 286–94. ©2014 AACR.