Infectious Disease

Hepatitis B

The vaccine currently used to protect humans was developed using the chimpanzee model. This vaccine, developed by Merck and tested for efficacy and safety by SFBR, is now administered to children so that current and future generations can grow up free from HBV infection. Hepatitis B is a disease with potentially devastating effects, and it is the world's leading cause of liver cancer.

Hepatitis C

The hepatitis C research program at SFBR has offered the first evidence that an effective vaccine against hepatitis C should be possible. Hepatitis C virus (HCV) is estimated to infect 3 percent of the population worldwide and more than 2 percent of the U.S. population. The leading cause of liver failure and liver transplantation in the United States, HCV infection also accounts for approximately 25 percent of all hepatocellular carcinomas. The extraordinary genetic and antigenic diversity of HCV virus strains has been thought to make development of a successful vaccine impossible. However, SFBR researchers recently demonstrated that chimpanzees that had previously cleared infection with one strain of HCV showed protective immunity when challenged with other strains of the virus. This offers hope that a successful vaccine against all strains of hepatitis C could be on the horizon. SFBR pre-clinical trials with powerful new anti-viral therapies also suggest that new, less toxic therapies — and possibly a cure for hepatitis C — are just a few years away.

AIDS

Performed the first transmission of HIV to a chimpanzee. In collaboration with scientists at the National Institutes of Health, HIV-contaminated blood was used to infect a chimpanzee, creating an animal model to study the disease and potential therapies, including vaccines. Although chimpanzees may become infected with HIV, they do not progress to clinical disease as humans do. The development of this animal model has provided a valuable tool for AIDS research, allowing the following research successes at SFBR:

SFBR researchers have tested more than 25 vaccine candidates for HIV. Two of these vaccines protected chimpanzees from HIV infection and advanced to clinical trials with human subjects, with one going on to large-scale Phase III clinical trials. Other vaccine candidates are currently being tested in the chimpanzee model as scientists continue their hopeful search for a protective vaccine for HIV and AIDS.

A new antibody against HIV was shown to prevent infection in chimpanzees treated with the antibody either one hour before or one hour after exposure to HIV. Development of this technology will provide a new method for preventing HIV infection in health care workers accidentally exposed to HIV-contaminated blood. It also could provide an adjunct therapy for the possible prevention of mother-to-child transmission of the disease. Now SFBR scientists are collaborating on the development and testing of a highly promising AIDS vaccine that is based upon the same type of antibody.

Herpes B

Scientists at SFBR helped develop methods to rapidly diagnose and treat herpes B virus infections, which are transmitted from Asian monkeys to humans and have a high fatality rate for humans. At particular risk are researchers who handle rhesus monkeys and other macaques or those who work with these animals' tissues.

Respiratory Syncytial Disease (RSV)

Developed a new animal model for respiratory syncytial disease (RSV) using newborn baboons. This will aid in the development of a vaccine that will be given to pregnant females so that babies will be born with sufficient antibodies against RSV to prevent infection until their own immune system is mature enough to provide protection. RSV is associated with an estimated 90,000 hospitalizations and 4,500 deaths from lower respiratory tract disease annually. The virus also causes repeated infections throughout life.

Chagas Disease

Chagas disease is a parasitic disease in humans that causes several debilitating conditions, including heart failure and digestive disorders associated with the enlargement of the esophagus or colon. It is endemic in 21 countries, with an estimated 18 million persons infected and 100 million at risk of infection. Chagas disease is of increasing concern in the United States since both the vector and parasite are common throughout much of the country, including Texas.

SFBR scientists have characterized several families of 500 people or more in Brazil who have high rates of Chagas disease. With NIH funding, scientists are studying this population to identify potential genetic mechanisms that will explain why only 65 percent of the exposed population becomes infected and why 30 percent of infected individuals develop clinical disease.

Helminthic Infections

Working with 2,000 members of a single family in Nepal, SFBR scientists have localized two genes that contribute to susceptibility to roundworm infection. This is the first evidence establishing that human host genes influence susceptibility to an intestinal worm infection. Since roundworm infection has always been thought to be simply a function of poor environmental quality, the identification of genetic influences on the disease represents a major change in the understanding of risk factors for intestinal worm infections.

Equine Encephalitis

Scientists at SFBR isolated a new virus that causes equine encephalitis and is present in Mexican states that border Texas. This mosquito-borne virus is a new threat to livestock and humans living in Texas.

Dengue Hemorrhagic Fever

SFBR researchers identified structural differences in the DNA of dengue viruses that determine the severity of dengue hemorrhagic fever in humans. This will aid in the development of prevention strategies and treatment methods for dengue fever, which is spread by mosquitoes to humans. Infection with dengue viruses produces a spectrum of clinical illness that can result in fatal hemorrhagic disease.

Cancer Research