Obetech workers are engaged in a variety of projects relating to the field of obesity and specifically to virus-induced obesity. The main focus is on human adenovirus-36 (Ad-36), “the obesity virus”, because this virus has been shown to cause obesity in animals and is strongly linked to obesity in humans, both adults and children. Since there is no doubt this virus causes obesity, the areas of most interest now are identifying how the virus works, what problems or diseases the virus causes in addition to obesity, how to diagnose if a person has been infected with the obesity virus, finding drugs that will block infection with the virus and treat people who already have been infected, and finally to develop a vaccine that will prevent infection with the virus.
The way the obesity virus causes weight gain is by affecting the fat tissue directly. All fat tissue has “adult stem cells” present that may turn into fat cells if stimulated. Ad-36 infects fat cells and does two main things that produce obesity. First is to turn on enzymes and other factors in the fat cells that cause fat to accumulate in the fat cells. These enzymes cause fat molecules in the blood to be transferred into the fat cells, but also cause an increased production of fat from glucose (sugar) within the fat cell. This combination causes individual fat cells to get larger because of all the fat stored in them. In addition, Ad-36 increases factors within fat cells that go out into the fat tissue and cause the stem cells to turn into fat cells. The new fat cells then begin to store fat. The end result is that infected people have more fat cells and larger fat cells in their fat tissue.
Infection with the obesity virus causes very mild common cold symptoms. Most people hardly know they are ill. They then gradually begin to gain weight. The mildness of the first symptoms is unfortunate in a way because people do not know they have this serious illness. The only way to learn if a person has been infected with the obesity virus is to do a test for it. Obetech has been working on several different types of tests for Ad-36. The first types of tests are blood tests. The “gold standard” blood test is a serum neutralization test that measures antibodies against Ad-36 and is specific for Ad-36 infection. It is very time consuming and requires a lot of lab technician time. It takes two weeks to perform and involves growing cells in tissue culture, infecting them with Ad-36, and determining if a patient’s blood has antibodies against the virus that will protect the cells. It is quite expensive. Obetech developed a better, faster, and cheaper test called an ELISA. It can be done in 1-2 days. It must be done in a specialized laboratory with the proper equipment. Obetech is still working on developing a “strip test” that may be done at home, similar to a diabetic strip test or a home pregnancy test. The person will prick a finger with a small lancet (painless or almost painless) and place a drop of blood on the strip. If it turns color, the person is infected.
The problem with the ELISA test and the “strip test” is that they are not as accurate as the serum neutralization test. Both the ELISA and the strip tests are used as screening tests. If a person is positive with either of these tests, they will need to see their doctor for additional testing (just like a home pregnancy test requires that a positive person see their doctor for confirmation). The doctor will order a “gold standard” test, either the serum neutralization test described above or a PCR test. PCR stands for “polymerase chain reaction” and is the test seen on the CSI television program that is used to detect DNA (genetic material) on a cigarette butt.
Obetech has been working for several years on developing a PCR test to detect the presence of obesity virus DNA. It isn’t possible to do the test on blood, but viral DNA can be detected in fat tissue. This requires a needle fat biopsy. A needle (same size as the needle used for blood draws or blood donations) is placed into the fat tissue beneath the skin and a tiny amount of fat cells are drawn out. This test is easier than a blood draw because the doctor or nurse doesn’t have to find a vein. The DNA from the fat cells is measured in a special PCR machine that can detect a tiny amount of virus DNA. This test is as good as or better than a serum neutralization test and is cheaper.
Obetech is also working to develop drugs that will act against the obesity virus to prevent infection or to treat an infected person. We have found one candidate that works in a tissue culture experiment to block infection or prevent the obesity effect of the virus if the cells are already infected. It is very promising, but needs additional research before it can be used in humans or animals. Other potential antiviral agents are being tested.
Obetech is also working on a vaccine to prevent infection with the obesity virus. An effective candidate vaccine has been found that is highly effective in tissue culture experiments. We now need to do animal studies and human trials before it will be ready to give to humans. Once this is available on the market, people and animals can be protected from getting