Dale and Betty Bumpers Vaccine Research Center search   
Vaccines for Life
Office of the Director
Research Laboratories
Clinical Studies
Collaboration and Funding
Publications News Seminars Meetings Employment
Clinical Trials
About Clinical Trials Core
* Chief's Profile
* Program Areas
* Facts
* Meet the Staff
* FAQs
* Contact Us
* Virtual CTC Clinic Tour
VRC Clinical Trials
* Understanding Vaccine Clinical Trials
* Safeguards
* Vaccine Science
* Current VRC Clinical Trials
* Archive of VRC Clinical Trials
Update on HIV Vaccine
* IAVI Report: Ongoing Trials of Preventive HIV Vaccines (PDF) [Disclaimer]
* IAVI Report: AIDS Vaccine Trials 2006: Year in Review (PDF) [Disclaimer]
* Download presentation slides by Barney Graham, M.D., Ph.D.
AIDS Information
* HIV Statistics
* HIV Transmission
Join the Human Race against HIV/AIDS Join the Human Race against HIV/AIDS


Clinical Trials VRC Home
Vaccine Science

What is a vaccine?

A vaccine is a substance that stimulates the body's immune response; the goal of vaccination is to prevent or control an infection.

How are vaccines developed?

All products selected for use as a potential vaccine go through a rigorous screening process.

To design a preventive vaccine, researchers must start with an idea or strategy. The decision to move forward with human trials is based on pre-clinical results, availability of the product, and the anticipated promise of the approach based on related scientific findings. In addition, before an investigational vaccine can be administered to human subjects in the US, it must first undergo review by the US FDA and Institutional Review Boards at each clinical site.

What types of vaccines are studied in VRC Clinical Trials?

The VRC studies newer types of vaccine concepts for its work on HIV/AIDS, Biodefense and Re-Emerging Infectious Diseases including subunit vaccines, investigational recombinant vector vaccines, and DNA vaccines.

    * Subunit Vaccines
    Subunit vaccines, also known as "component" vaccines, contain only individual proteins or peptides from a virus, rather than the whole virus. Instead of collecting protein or peptide components from the virus itself, they are made in the laboratory using genetic engineering techniques.
    * Recombinant Vector Vaccines
    Recombinant vector vaccines are based on microorganisms such as viruses or bacteria that have been weakened so as not to cause disease. The viruses or bacteria are used as vectors, or carriers, to deliver genes into the cells of the body. The body produces proteins from the genes and these proteins stimulate an immune response similar to that induced by other types of vaccine or natural infection.
    * DNA Vaccines
    DNA vaccines introduce pieces of laboratory-made virus DNA into the body. Unlike recombinant vector vaccines, DNA vaccines do not rely on a viral or bacterial vector. Instead, "naked" DNA containing synthetic viral genes is injected directly into the body. Cells take up this DNA and use it to produce virus proteins. The proteins trigger the body to produce an immune response without a risk of infection from either the virus of interest or a vector.

Continue here for additional Understanding Vaccines and Understanding Immune Responses information.




NIH Home

Department of Health and Human Services / National Institutes of Health / National Institute of Allergy and Infectious Diseases
Vaccine Research Center / 40 Convent Drive / Bethesda, Maryland 20892
E-mail the VRC / Directions and Maps / Site Map

Office of the Director | Research Laboratories | Clinical Studies | Collaboration and Funding
NIAID Website Privacy Statement | NIAID Website Accessibility Statement

Last updated: 02.04.08 (alt)

National Institute of Allergy and Infectious Disease Home