Texas Tech University

Ebenezer Tumban, MS, PhD

Associate Professor of molecular virology and vaccinology

  • Phone: 806.834.0472
  • Email: etumban@ttu.edu
  • Area of Expertise: Viral infectious diseases, Molecular virology, virus-like particles bioengineering, vaccines & correlates of immune protection, and immunizations.
  • Publications:

About Me

Dr. Tumban is a molecular virologist and vaccinologist by training. Before joining Texas Technological University, Dr. Tumban was an Associate Professor and the Graduate Program Director of the Department of Biological Sciences at Michigan Technological University (MTU).

Instruction

He enjoys educating students on infectious agents (viruses, bacteria, fungi), the biology of cancer, and the body's response to infectious agents.

Research

Dr. Tumban has worked on so many research projects ranging from assessing the molecular determinants of arboviruses (such as dengue and Langat viruses) modes of transmission, the generation of recombinant antigens for developing immunodiagnostic kits against infectious agents (e.g. dengue viruses), to the development of candidate vaccines against viral infectious agents. Dr. Tumban is a co-inventor on a U.S./European Union patent for a virus-like particle (VLP)-based L2 candidate vaccine against human papillomaviruses, which is licensed to Agilvax Biotech. He is currently interested in developing and testing candidate VLP-based subunit vaccines against viral infectious agents.

Vaccines against infectious agents can be developed using conventional or non-conventional approaches. A non-conventional approach utilizes a portion of an infectious agent to develop a subunit vaccine. Subunit vaccines are very safe. However, subunit vaccines especially those based on peptide antigens are very small and unstable in serum. Additionally, they lack the size and geometry required to elicit robust immune responses. As such, peptide vaccines must be immunized, as a complex with a carrier protein, at multiple large (microgram) doses to elicit a good immune response. Research in the Tumban Lab focuses on developing and assessing strategies to enhance the immunogenicity of subunit vaccines against viral infections. Our research falls under three broad projects:

Project I: Development of novel virus-like particle (VLP) platforms.
VLPs, derived from the expression of viral structural proteins, are empty shells that consist of one or more types of multimeric coat or envelope proteins arranged geometrically into dense repetitive arrays (Figure 1). They are morphologically and structurally similar to viruses from which the coat proteins are derived and thus, VLPs are highly immunogenic, even at small doses of antigens. VLPs can therefore be used as a display platform to enhance the immunogenicity of peptide vaccines. To overcome the limitation of the immunogenicity of peptide vaccines, we are interested in developing novel VLP platforms that can be used to display, multivalently, peptide antigens with the ultimate goal of eliciting robust peptide immune responses at nanogram doses.

Figure 1
Figure 1

Project II: Development of VLP-based peptide vaccines against zoonotic/mosquito-borne viral infections.
Zika virus (ZIKV) and Chikungunya virus (CHIKV) are single-stranded positive-sense RNA viruses, which are transmitted between monkeys and/or humans by mosquitoes. ZIKV infection is associated with fever, skin rash, and congenital syndrome while CHIKV infection is also associated with fever in addition to polyarthralgia. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), another virus of research interest, is transmitted through respiratory droplets from bats (or unknown animal reservoirs) to humans and/or from humans to humans; SARS-CoV-2 is associated with COVID-19. Currently, there are no approved drugs or vaccines to prevent against this viral infection. Antibody-neutralizing epitopes (Figure 2). have been identified against these viruses; however, the neutralization/protection potential of some of these epitopes have not be fully explored. Our lab is interested in developing VLP-based subunit vaccines targeting some of these neutralizing epitopes.

Figure 2
Figure 2

Publications:
  1. Basu R., Zhai L., Rosso B., and Tumban E. (2020). Bacteriophage Qβ Virus-like Particles Displaying Chikungunya Virus B-cell Epitopes Elicits high-titer E2 protein antibodies but fail to neutralize a Thailand strain of Chikungunya virus. Vaccine, 38(11):2542-2550.
  2. Basu R., Zhai L., Contreras A., and Tumban E. (2018). Immunization with Phage Virus-like Particles Displaying Zika Virus B-cell Epitopes Neutralizes Zika Virus Infection of Monkey Kidney Cells. Vaccine 36(10):1256-1264.

Project III: Development of VLP-based subunit vaccines against sexually transmitted viral infections. Human papillomaviruses (HPVs) are DNA viruses; they are the most sexually transmitted infections. About 19 HPV types cause cancer (cervical cancer, penile cancer, head and neck cancers) while other types cause genital warts. Current HPV vaccines especially Gardasil-9 protect against HPV types that cause ~90 of cervical cancer and ~86% of HPV-associated penile cancer; the vaccines also protect against ~90% of genital warts. Because some HPV types associated with cervical/penile cancers (~10%) are not protected by these vaccines, there is a concern that vaccinated individuals may still be infected with non-vaccine HPV types. We are interested in developing VLP-based subunit vaccines targeting conserved epitopes (on the minor capsid protein, L2) shared by 19 cancer-causing HPV types. We have shown that immunization with nanograms of VLPs displaying a concatemer peptide of L2 offers protection against diverse HPV pseudoviruses (Figure 3).

Figure 3
Figure 3

Publications:
  1. Yadav R., Zhai L., Tumban E. (2019). Virus-like Particle-Based L2 Vaccines against HPVs: Where Are We Today? Viruses, 12(18):1-17
  2. Tumban E. (2019). A current update on human papillomavirus-associated head and neck cancers. Viruses 11(10):1-19.
  3. Zhai L., Yadav R., Kunda NK., Anderson D., Bruckner E., Miller E., Basu R., Muttil P. and Tumban E. (2019). Oral immunization with bacteriophage MS2-L2 VLPs protects against oral and genital infection with multiple HPV types associated with head & neck cancers and cervical cancer. Journal of Antiviral Research 166:56-65.
  4. Kunda NK., Peabody J., Zhai L., Price DN, Chackerian B., Tumban E., Muttil P. (2019). Evaluation of the thermal stability and the protective efficacy of spray-dried HPV vaccine, Gardasil® 9. Human Vaccine Immunotherapy 18:1-8.

Service

Dr. Tumban is an ad hoc reviewer for many scientific journals (including the Journal of Vaccine and the Journal of Antiviral Research) and he has served on grant review panels for the Department of Defense (U.S. Army Medical Research and Materiel Command's Office of Congressionally Directed Medical Research Grants). He was one of the lead investigators at MTU who set up a COVID-19 testing laboratory on campus during the SARS-CoV-2 pandemic. He also prepared and supplied viral transport medium to hospitals/clinics for COVID-19 testing in the Upper Peninsula in Michigan.

School of Veterinary Medicine