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Oklahoma State University

Josh D. Ramsey

Dr. Josh RamseyAssociate Professor and Robert N. Maddox Professorship

josh.ramsey@okstate.edu

 

ACADEMIC BACKGROUND

PhRMA Foundation Fellow, University of Kansas, 2007

Ph.D., Chemical  & Biomolecular Engineering, University of Illinois, 2006

M. S.,  Chemical Engineering, University of Illinois, 2003

B. S.,  Chemical Engineering, Oklahoma State University, 2000

 

MAJOR AREAS OF RESEARCH

Novel Gene Delivery Vectors

Macromolecular (Genes and Proteins) Drug Delivery

Directed Evolution of Enzymes

Virtual Design and Screening of Therapeutic Compounds

 

RECENT RESEARCH ACTIVITIES

Engineering Novel Gene Delivery Vectors

Safe and efficient delivery of genetic material remains a serious challenge limiting the field of gene therapy.  Our group is interested in developing novel methods for gene delivery.  We are currently funded by the National Science Foundation to investigate hybrid viral/synthetic gene delivery vectors that may ultimately lead to the design of better biomaterials for gene therapy vectors.

Macromolecular Drug Delivery

Protein therapeutics, like genes, pose a unique set of challenges when it comes to drug delivery.  We have been working with a polyethylene glycol-grafted-polylyine copolymer to encapsulate and deliver a range of proteins that can be used for treating cancer or providing protection from chemical warfare agents.

Virtual Design and Screening

Using neural networks and large chemical databases (NCI 60) of growth inhibition, we have developed a virtual design and screening platform to predict (i) the likely mechanism of action of a potentially novel chemotherapy drug and (ii) the growth inhibition effects of the potential drug.  This approach may lead to discovery of novel drugs for treating cancer or allow for in silico prediction of the synergistic effects of combination therapy.

Improving Industrial Relevant Enzymes and Microorganisms

Directed evolution is a technique that has been used to successfully re-engineer enzymes for a variety of applications.  Such enzymes show enhanced or novel substrate activity, improved stability in organic solvents, or greater thermostability.  Our lab is interested in using this technique to produce novel enzymes and microorganisms.

 

RECENT PUBLICATIONS
M. Amer and J.D. Ramsey, “Multi-Chamber Single-Use Bioreactor – A Proof of Concept Prototype.” Biochemical Engineering Journal 130 (2018), 113-120, 2018.

K. Sahoo, S. Karumuri, R. Hikkaduwa Koralege, N.H. Flynn, S. Hartson, J. Liu, J.D. Ramsey, K. Kalkan, C. Pope, A. Ranjan, “Molecular and biocompatibility characterization of red blood cell membrane targeted and cell penetrating peptide-modified polymeric nanoparticles.” Molecular Pharmaceutics, 14 (7), 2224-2235, 2017.

K. Poindexter, J. Liu, N.H. Flynn, L. Sultatos, L. Geng, S. Brimijoin, J.D. Ramsey, S. Hartson, A. Ranjan, and C. Pope, “Polyionic Complexes of Butyrylcholinesterase and Poly-L-lysine-g-poly(ethylene glycol): Comparative Kinetics of Catalysis and Inhibition and in vitro Inactivation by Proteases and Heat.” Chemico-Biological Interactions 275 (2017), 86-94, 2017.

G. Kupgan, S.P. Choudhari, N.H. Flynn, A.N. Nigatu, S. Vupputuri, W.D. Picking, W.L. Picking, and J.D. Ramsey, “Identification of Excipients for Stabilizing Fiberless Adenovirus as Biopharmaceuticals.” Journal of Pharmaceutical Sciences, 106 (7), 1764 – 1771, 2017.

M. Rasoulianboroujeni, G. Kupgan, F. Moghadam, M. Tahriri, A. Boughdachi, P. Khoshkenar, J.J. Ambrose, N. Kiaie, D. Vashaee, J.D. Ramsey, and L. Tayebi, “Development of a DNA-Liposome Complex for Gene Delivery Applications.” Material Science and Engineering C, 75, 191-197, 2017.

S. Koteeswaran, J.C. Pashin, J.D. Ramsey, and P.E. Clark, “Quantitative Characterization of Polyacrylamide-Shale Interaction under Various Saline Conditions.” Petroleum Sciences. 14, 586-596, 2017.

N.H. Flynn, Ç. Ö. Topal, R.S. Hikkaduwa Koralege, S. Hartson, A. Ranjan, J. Liu, C. Pope, and J.D. Ramsey, “Effect of Cationic Grafted Copolymer Structure on the Encapsulation of Bovine Serum Albumin.” Material Science and Engineering C, 62, 524-531, 2016.

K. Sahoo, R. Hikkaduwa Koralege, N. Flynn, S. Koteeswaran, P. Clark, S. Hartson, J. Liu, J.D. Ramsey, C. Pope, and A. Ranjan, “Nanoparticle Attachment to Erythrocyte via the Glycophorin A Targeted Ery1 Ligand Enhances Binding without Impacting Cellular Function.” Pharmaceutical Research, 33 (5), 1191-1203, 2016.

G. Premaratne, R. Nerimetia, R. Matlock, L. Sunday. R. Hikkaduwa Koralege, J.D. Ramsey, and S. Krishnan, “Stability, Scalability, and Reusability of a Volume Efficient Biocatalytic System Constructed on Magnetic Nanoparticles.” Catalysis Science & Technology, 2016 (6), 2361-2369, 2016.

S. Nasrazadani, R. Eghtesad, E. Sudoi, S. Vupputuri, J.D. Ramsey, and T. Ley, “Application of Fourier Transform Infrared Spectroscopy to Study Concrete Degradation Induced by Biogenic Sulfuric Acid.” Materials and Structures. 5 (49), 2025-2034, 2016.

C. Pope, C. Uchea, N.H. Flynn, K. Poindexter, L. Geng, W.S. Brimijoin, S. Hartson, A. Ranjan, J.D. Ramsey, and J. Liu, “In Vitro Characterization of Cationic Copolymer-Complexed Nanoparticles of Human Butyrylcholinesterase.” Biochemical Pharmacology, 98 (3), 531-539, 2015.

J.D. Ramseyand N.H. Flynn, “Cell-Penetrating Peptides Transport Therapeutics into Cells.” Invited Review, Pharmacology & Therapeutics, 154, 78-86, 2015.

N. Flynn and J.D. Ramsey. Virus-Like Particles in Gene, Vaccine, and Therapeutic Delivery. In Nanoparticles for Biotherapeutic Delivery (Vol. 1). London, UK: Future Science Ltd. 38-48, 2015.

A.S. Nigatu, N. Flynn, S. Vupputuri, and J.D. Ramsey, “Effects of Cell-Penetrating Peptides on Transduction Efficiency of PEGylated Adenovirus.” Biomedicine and Pharmacotherapy, 71 (2015), 153-160, 2015.  

S. Vupputuri, B. Fathepure, G. Wilber, S. Nasrazadani, T. Ley, J.D. Ramsey, “Characterization of an Acid-Producing Microorganism Collected from a Deteriorating Bridge Site.” International Biodeterioration & Biodegradation, 97 (Jan.-Feb.), 128-134, 2015.

G. Kupgan, D. Hentges, N. Muschinske, W.D. Picking, W.L. Picking and J.D. Ramsey, “The Effect of Fiber Truncations on the Stability of Adenovirus Type 5.” Molecular Biotechnology, 56 (11), 979 – 991, 2014. 

S.P. Choudhari, K. Pendleton, J.D. Ramsey, T. Blanchard and W.D. Picking, “A Systematic Approach Toward Stabilization of CagL, a Protein Antigen from Helicobacter pylori that is a Candidate Subunit Vaccine.” Journal of Pharmaceutical Sciences, 102 (8), 2508 – 2519, 2013. 

N.A. Alhakamy, A.S. Nigatu, C.J. Berkland and J.D. Ramsey, “Gene Delivery Applications of Noncovalently Associated Cell-Penetrating Peptides.” Therapeutic Delivery, 4 (6), 741 – 575, 2013.

E. Whitebay, B. Neely, K.G. Gasem and J.D. Ramsey, “In Silico Prediction of Mechanism of Action for Cancer Therapeutics.” Molecular Informatics, 32 (8), 735 – 741, 2013. 

A. Nigatu, S. Vupputuri, N. Flynn, B.J. Neely and J.D. Ramsey, “Evaluation of Cell Penetrating Peptide-Adenovirus particles for Transduction of CAR-Negative Cells.” Journal of Pharmaceutical Sciences, 102 (6), 1981-1993, 2013.

S. Vupputuri, S. Karode, B.J. Neely and J.D. Ramsey, “Protein Impurities from Cell Culture Dramatically Impact Transduction Efficiency of Polymer/Virus Hybrid Vectors.” Journal of Virological Methods, 92 (2013), pp. 1-11, 2013.

K. Singarapu, I. Pal, and J.D. Ramsey, “Modified Polyethylenimine Used to Enhance Adenovirus Gene Delivery.” Journal of Biomedical Materials Research: Part A, 101A, 1857 – 1864, 2013.